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ENHANCEMENTOF
SYNGASPRODUCTION
USINGAGRI-WASTE
TECHNOLOGY
PLANT DESIGN
PROJECT REPORT
Tug of War:
Fossil Fuels against
Ren...
I
ACKNOWLEDGEMENT
First and foremost, we would like to express our deepest appreciation to the Faculty of
Chemical Enginee...
II
TABLE OF CONTENTS
Page
1.0 INTRODUCTION ..................................................................................
III
Appendix D: Process Flow Diagram, Stream Table, Utilities, Mass and Energy Balance
(Before Optimization) ................
IV
LIST OF FIGURES
Figure1.1. World primary energy supply (Botha 2012) ......................................................
V
LIST OF TABLES
Table 1.1: Raw materials and product specification................ Error! Bookmark not defined.
Table 2.1...
VI
EXECUTIVE SUMMARY
Following the recent focus in biomass gasification as alternative feed to fossil fuels for its
minima...
1
1.0 INTRODUCTION
The global demand for energy and biofuels is experiencing a rising trend with the growth of
the world p...
2
1.2 Market Survey
The price trend of the raw materials and the current demand trend of the product are
investigated. In ...
3
Kyoto Protocol by enforcing laws throughout different continentals. As with the fact that
fossil fuel is still dominatin...
4
usually in a range of 8 to 10% moisture content and 15MJ/kg of calorific value (Bronzeoak
2003). To combat energy crisis...
5
thick beds near the surface, resulting in low mining cost and correspondingly, lower prices in
70-80 USD/tonne (EIA 2011...
6
separated into a pure hydrogen stream via the shift reaction. This is summarized in Figure
1.4 below.
Figure 1.4. Syngas...
7
syngas at a rate of 0.316 m3/s, for which this 60 % H2 composition in syngas can provide
higher efficiency in electricit...
8
A.4 and Table A.5 (Appendix A). The fluidized bed and fixed bed are the most common
type of gasifiers used for co-gasifi...
9
Lastly, the comparison of worldwide similar operating plants, based on its development status
and product syngas charact...
10
industries from industries in Samalauju Industrial Park is also observed in SCORE. It should
be noted that although the...
11
2.0 DESIGN METHODOLOGY
The basis of design, assumptions, simulation specifications and, the mass and energy balance
is ...
12
the previous section. A more detailed process flow diagram and the simulation stream table
are illustrated in Figure D ...
13
The HRSG, which covers the cooling section, features a quencher, a superheater heat
exchanger, a medium pressure (MP) a...
14
2.2 Material and Energy Balance
Mass and energy balances are performed in order to compare the result from theoretical
...
15
desulphurizer and water gas shift reactor which require duty are taken into consideration. The
total heat required befo...
16
Thus a cost saving of 82.7% is achieved, with an increase in hydrogen yield of 12.9% from
82.3% of base case to 92.9%. ...
17
3.0 PROFITABILITY ANALYSIS
To investigate the profitability viability, the equipment schedule and pipe specifications a...
18
4.0 RISK ASSESSMENT
The vulnerability of the plant is assessed in this section in terms of economic, safety and
environ...
19
area for ease of fire extinguishing in case of any emergency while assembly points are
available at emergency evacuatio...
20
5.0 CONCLUSION
The implementation of biomass gasification as alternative feed to substitute fossil fuels usage
in energ...
21
REFERENCES
Adrian K., James,Thring Ronald W., Rutherford P. Michael, and Helle Steve S. 2013.
'Characterization Of Biom...
22
C.H. Wong, C. Desmond;, S.Y.Yin and Y.L. Lee;. 2011. Gas & Electricity Tariff Hikes. Accessed
August 18, http://maybank...
23
G. Okten, O.Kuraland E. Algurkaplan. Storage of Coal: Problems and Precautions. Turkey.
Gasification Status and Technol...
24
Kothandaraman, Anusha. 2005. Carbon Dioxide Capture by Chemical Absorption: A Solvent
Comparison Study. PhD thesis.
htt...
25
Mohanty, Samarendu. 2014. "Rice in South Asia." April- June. Accessed August 14, 2015.
http://www.scribd.com/doc/217353...
26
Rohan. n.d. Global Forecasts to 2020. Accessed August 15, 2015.
http://www.marketsandmarkets.com/PressReleases/syngas.a...
27
Tanks, BNH Gas. 2015. Syngas Tank. Accessed August 17, http://www.syngastank.com/.
The Star Online 2014. CMS Subsidiary...
28
APPENDICES
Appendix A: Product, Raw Materials and Process Technology Evaluation
Prior process screening, the type of ag...
29
Table A.2. Utilization of by-product
Residues Ash Char Tar
Reutilization
/ Disposal
- As a partialreplacement for the
s...
30
Table A.6. Summary of comparison between various types of gasifiers
Criteria Fixed bed updraft
gasifier
Fixed bed
downd...
31
Table A.6. Summary of comparison between various type of gasifiers (continued)
Criteria Fixed bed updraft
gasifier
Fixe...
32
Table A.7. Summary of different type of fluidized bed gasification processes (continued)
Criteria Bubbling Fluidized Be...
33
Table A.9. Summary of similar operating plant with CFB technology
Criteria Foster Wheeler Uhde Fraunhofer Umsicht
Techn...
34
Appendix B: Process Plant Site Selection
Table B. Comparison for Site Selection
Factors Site 1: Samalaju, SCORE, Malays...
35
Table B. Comparison for Site Selection (continued)
Factors Site 1: Samalaju, SCORE, Malaysia Site 2: Jababeka, Cikarang...
36
Appendix C: Process Simulation Basis of Design
Table C.1. Property method, model and general assumptions for simulation...
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
NACES Plant Design Report - SynTech Curtin Sarawak
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NACES Plant Design Report - SynTech Curtin Sarawak

  1. 1. ENHANCEMENTOF SYNGASPRODUCTION USINGAGRI-WASTE TECHNOLOGY PLANT DESIGN PROJECT REPORT Tug of War: Fossil Fuels against Renewables LEAD DESIGNERS: SAM TZE MUN (920720075054); LEE REN JIE (930405085243); LIM SHIH CHIANG (921203135201); MONG IRENE (930323145708); SHERON LIM GEK JOO (930330136084) YEAR OF STUDY: 4TH YEAR (FINAL YEAR) CONTACT:+6012-4159110 | 7E1B8965@STUDENT.CURTIN.EDU.MY
  2. 2. I ACKNOWLEDGEMENT First and foremost, we would like to express our deepest appreciation to the Faculty of Chemical Engineering of Curtin University Sarawak Campus for giving us the opportunity to participate in the National Chemical Engineering Symposium (NACES) Process Plant Design Competition in our final year. Next, we would like to express our gratitude to our supervisor, Dr. Jibrail Kansedo for all the sincere help from providing insight in various aspects to recommending useful and reliable resources with clear explanation. He is very approachable and welcomes any enquiries in the form of email and face-to-face discussion. We definitely will not be able to commence the design without his advices. Lastly we would like to express our indebted gratitude to Dr Bridgid Chin Lai Fui, the advisor for this category in providing relevant information and advices that are proved useful in research and report writing. We would not be able to complete this report smoothly without her sincere guidance.
  3. 3. II TABLE OF CONTENTS Page 1.0 INTRODUCTION ..........................................................................................................1 1.1 Design Background.....................................................................................................1 1.2 Market Survey.............................................................................................................2 1.2.1 World energy consumption and supply ...............................................................2 1.2.2 Hydrogen Economy .............................................................................................3 1.2.3 Global agri-waste production...............................................................................3 1.2.4 Sub-bituminous coal supply.................................................................................4 1.2.5 Syngas market......................................................................................................5 1.3 Raw Materials .............................................................................................................7 1.4 Process Screening........................................................................................................7 1.5 Site Selection...............................................................................................................9 1.6 Problem Statement ....................................................................................................10 1.7 Proposed Solution .....................................................................................................10 2.0 DESIGN METHODOLOGY........................................................................................11 2.1 Design Process Description.......................................................................................11 2.1.1 Basis of design ...................................................................................................11 2.1.2 Process overview................................................................................................11 2.2 Material and Energy Balance ....................................................................................14 2.3 Heat Integration.........................................................................................................14 2.4 Process Optimization.................................................................................................15 2.5 Process Control .........................................................................................................16 3.0 PROFITABILITY ANALYSIS ....................................................................................17 3.1 Capital and Operating Cost Investment ....................................................................17 3.2 Economic Scenario Analysis: Base, Best and Worst Case .......................................17 4.0 RISK ASSESSMENT...................................................................................................18 4.1 Economic Aspect.......................................................................................................18 4.2 Safety Aspect and HAZOP Assessment....................................................................18 4.3 Environmental Aspect...............................................................................................19 5.0 CONCLUSION.............................................................................................................20 REFERENCES ........................................................................................................................21 APPENDICES .........................................................................................................................28 Appendix A: Product, Raw Materials and Process Technology Evaluation........................28 Appendix B: Process Plant Site Selection............................................................................34 Appendix C: Process Simulation Basis of Design ...............................................................36
  4. 4. III Appendix D: Process Flow Diagram, Stream Table, Utilities, Mass and Energy Balance (Before Optimization) ..........................................................................................................41 Appendix E: Heat Integration ..............................................................................................60 Appendix F: Optimization Parameters, Stream Table and Process Flow Diagram (After Optimization) .......................................................................................................................66 Appendix G: Piping and Instrumentation Diagram (PID) ...................................................74 Appendix H: Equipment Schedule and Pipe Sizing Specifications .....................................77 Appendix I: Equipment Costing and Methodology .............................................................80 Appendix J: Economic Assumptions and Capital Cost Calculation....................................98 Appendix K: Layout Plan and Safety Features .................... Error! Bookmark not defined. Appendix L: Key Issues for Plant Commissioning, Start-up and Shutdown.....................111 Appendix M: Environmental Risk Assessment .................................................................113
  5. 5. IV LIST OF FIGURES Figure1.1. World primary energy supply (Botha 2012) ............................................................2 Figure 1.2. Global rice husk production (Bronzeoak 2003) ......................................................4 Figure 1.3. Estimated world coal production from 1985 to 2100 (Hook et al. 2010)................5 Figure 1.4. World primary energy demand (Energy Security n.d.) ...........................................6 Figure 1.5. Syngas Usages (Syngas 2015).................................................................................6 Figure 1.6. Proposed site area for plant design (Score 2015) ....................................................9 Figure 2.1. Process flow diagram of co-gasification of coal and biomass plant design ..........12 Figure 2.2. Flowchart for energy integration workflow ..........................................................14 Figure 2.3. Composite Curves .................................................................................................60 Figure 2.4. Process flow diagram after optimization...............................................................16 Figure D. Process flow diagram before optimization ..............................................................41 Figure F. Process flow diagram after optimization..................................................................67 Figure G. PID for process plant ...............................................................................................74
  6. 6. V LIST OF TABLES Table 1.1: Raw materials and product specification................ Error! Bookmark not defined. Table 2.1. Total Flowrate of Utilities....................................... Error! Bookmark not defined. Table 2.2. Energy saving from hot and cold utilities ...............................................................15 Table 2.3. Total utilities cost before and after process optimization .......................................66 Table A.1. Fractional atom economy calculation ....................................................................28 Table A.2. Calculation of raw materials gasification process economy..................................29 Table A.3. Summary of comparison between various types of gasifiers.................................30 Table A.4. Summary of different type of fluidized bed gasification processes.......................31 Table A.5. Evaluation on various desulphurization process technologies...............................32 Table A.6. Summary of similar operating plant with CFB technology ...................................33 Table B. Comparison for Site Selection ..................................................................................34 Table C.1. Property method, model and general assumptions for simulation thermodynamics ..................................................................................................................................................36 Table C.2. Ultimate analysis (% wt) of coal and rice husk by dry ash free basis....................36 Table C.3. Proximate analysis (% wt) of coal and rice husk ...................................................36 Table C.4. Sulphur analysis (% wt) of coal with 1.97% sulphur in ultimate analysis.............36 Table C.5. Key equipments, feeds and process stream specifications for design basis input .37 Table D.1. Base case flowsheet ...............................................................................................41 Table D.2. Heating and cooling utilities ..................................................................................48 Table E.1. Data Extracted from Aspen Energy Analyzer and Shifted Temperature ...............60 Table E.2. Sub-Networks and Cascading Process ...................................................................63 Table E.3. Cascade Diagram....................................................................................................64 Table F.1. Flowsheet optimization...........................................................................................66 Table F.2. Optimized case flowsheet....................................... Error! Bookmark not defined. Table G. Process control philosophies for each equipments ...................................................75
  7. 7. VI EXECUTIVE SUMMARY Following the recent focus in biomass gasification as alternative feed to fossil fuels for its minimal environmental impact, the co-gasification of coal and renewable carbon-based biomass has become a new area of research and attractive design approach due to its ability to reduce greenhouse gas emissions and improve energy efficiency. A plant design is proposed at Samalaju Industrial Park, Sarawak, Malaysia with the highlight of co-gasification technology using sub-bituminous coal and rice husk at 1:1 ratio to achieve high gas yield, low tar and char yield, as well as high thermal efficiency with effective HRSG and desulphurization gas cleaning technology that promotes sustainable development in environmental, economics, safety and resources aspects. A promising alternative to the conventional processes is provided with significant focus in process safety for which risk assessment, HAZOP, contingency plan and start-up and commissioning procedures are readily available. Material and energy balance calculation performed has proved the design feasibility followed by heat integration and process optimization with the optimized process flow diagram shown in Appendix F (page 69).The proposed plant design is capable of producing 50 kilo-tonnes of hydrogen-rich syngas annually with TAC of RM 3,527,888,385.34 and a payback period of 0.55 years with energy saving of 82.7%. KEYWORD: Plant Design, Co-Gasification, Rice Husk, Sub-Bituminous Coal, HRSG, Heat Recovery Steam Generator, Desulphurization
  8. 8. 1 1.0 INTRODUCTION The global demand for energy and biofuels is experiencing a rising trend with the growth of the world population and economic development in recent years. The background of the proposed design, market survey, process screening, proposed site and solution are covered to introduce an alternative plant design using agri-waste technology to meet energy demand. 1.1 DesignBackground The well-established gasification technology is commonly used to transform fossil fuels such as coal or biomass respectively into synthesis gas, often abbreviated as syngas, for subsequent refining or utilization as combustible gas or industrial feedstock. The highlight of this plant is the design of co-gasification process using coal and agricultural biomass waste, rice husks as fuel to produce approximately 50 kilo-tonnes per year of syngas, with a high target yield of hydrogen rich syngas. The gasifier is fed with rice husk and coal at a ratio of 1:1 with steam in order to achieve high gas yield, low tar yield, low char yield and high thermal efficiency (Krerkkaiwan et al. 2013). Co-generation is defined as the production of electricity (mechanical power) and heat such as high temperature liquid and steam to provide a more efficient energy system which maximizes the utilization of waste heat from electricity production (Cogeneration 2012). By introducing the co-generation system, the raw product gas is processed through a Heat Recovery Steam Generator (HRSG) to meet the required temperature for subsequent wet scrubbing as well as generation of mechanical power. As further gas cleaning and treatment is required to meet pollutant emission limits and environment policy, the crucial gas cleaning steps involved desulphurization where gaseous contaminants such as H2S is removed before it is processed in the water gas shift reactor for a higher hydrogen rich syngas yield (Sciubba 2009). The desulphurization technology focuses in the regeneration of the metal absorbent used in sulphidation and it produces sulphur as one of the by-product. Hence, the proposed green plant design using co-gasification and desulphurization technology aims to give a promising alternative to the conventional processes with potential all year round profitability by meeting market requirement and operational sustainability in terms of resource utilization, social responsibility and environmental commitment.
  9. 9. 2 1.2 Market Survey The price trend of the raw materials and the current demand trend of the product are investigated. In order to meet customers’ needs and expectations, marketing research is crucial in allocating the readily available products and services to them. (Market Research 2010). The primary research is to gather data from analyzing current sales and the effectiveness of current practices. 1.2.1 World energy consumption and supply Following the increase in global population, industrialization development is expected to double up the world primary energy requirements, reaching 3.2% increment annually by 2050 (Botha 2012). As mentioned by the International Energy Agency Report, fossil fuels undeniably contributed 81.4% to the world energy supply, for which 68% of it is used in electricity generation. However a high percentage of the world primary energy supply is from the gas sector as shown in Figure 1.1. Figure1.1. World primary energy supply (Botha 2012) Greenhouse gases are generated from burning activities of fossil fuels, where the primary components consists of carbon dioxide (CO2), water and methane. The carbon dioxide itself is capable of absorbing solar heat radiation, fabricating an insulation layer around the earth by preventing heat radiation to escape inside out and ultimately increasing surrounding temperature. According to Elder and Allen (2009), the concentration of CO2 has increased tremendously (35%) from year 1750 to 2005, events including glacial retreat that caused sea level to rise and the extinction of natural habitats and catastrophic physical consequences began to occur with the alarming rate of global warming. According to Botha (2012), this global warming phenomenon had led to heavy investigation for a more efficient way to reduce the production of greenhouse gases. A few initiative steps had been taken by the United Nations Framework Convention on Climate Change (UNFCCC) in reference to the 21% 6% 2% 10% 26% 34% 1% Gas Nuclear Hydro Biomass Coal/peat Oil Others
  10. 10. 3 Kyoto Protocol by enforcing laws throughout different continentals. As with the fact that fossil fuel is still dominating the energy supply industry, it is necessary to develop a more innovative technology pathway to ensure a sustainable future for the coming generations. 1.2.2 Hydrogen Economy Hydrogen is envisioned as a clean energy carrier which has the potential to replace fossil fuel in the future (Hui Liu 2012). As hydrogen is highlighted as a high energy content producer with zero pollution in the combustion phase, it can be the alternative energy resource to reduce greenhouse gas emissions. Hydrogen is commonly used in fuel cells for electricity production where recently, hydrogen market price spur significantly with introduction of the newly Integrated Gasification Combined Cycle (IGCC) technology (Long et. al 2011). Scientists found out that the fuel cells are capable of producing electricity up to an efficiency of 50%. Moreover, hydrogen can be utilized to produce synthetic petroleum from coal in Fischer Tropsch process (Botha 2012). Hydrogen rich gas can be produced from fossil fuels such as coal and water while the current conventional supplies are from steam reforming or thermal cracking using natural gas. Ironically, the down-side of using fossil fuel is the large amount of greenhouse gases emitted, which defeated the purpose of producing hydrogen as it is considered as a clean fuel. Meanwhile, hydrogen can also be produced by splitting water, through a CO2 free process, or even High Temperature Electrolysis, nevertheless this required a relatively high temperature environment (Botha 2012). The process of producing hydrogen using water is usually more expensive than using steam gasification of coal or biomass. In comparison, more benefits are provided in terms of carbon dioxide emissions, environmental implications, primary energy availability and hydrogen production costs using co-gasification, which will be discussed in the upcoming section. 1.2.3 Global agri-waste production Rice from the agricultural industry are cultivated around the globe, it is the primary source of food for billions of people. Rice production in China is the highest followed by India, the Asia region. According to Bronzeoak (2003), the global rice production is increasing at a rate of 10% from year 1992 to 2002. Part of the rice, rice husk which is not eaten is claimed to be an agri-waste where in reality, rice husks are listed as one of the largest readily available but most under-utilized biomass resources, being classified as an ideal fuel for electricity generation. The calorific value is different on rice variety, bran and moisture content but
  11. 11. 4 usually in a range of 8 to 10% moisture content and 15MJ/kg of calorific value (Bronzeoak 2003). To combat energy crisis, rice husk is selected as a resource for energy production for those countries that primarily depend on imported oil resources (Ajay et. al 2012). About 770 million tonnes of rice husks is produced in Asia yearly (Santiaguel 2015). According to TIFAC (2014), the rice husks price ranged from 20- 50 MYR/tonne with respect to industrialized states and regions. A tremendous increase from 2 million tonnes rice is exported in the early 1990s to 14 million tonnes in 2013 as observed for South Asia country (Mohanty 2014). The production of rice husks produced globally is observed in Figure 1.2. Figure 1.2. Global rice husks production (Bronzeoak 2003) Thus rice husk is selected as the preferable biomass feedstock as it does not require any pre- treatment process throughout the gasification process. The ash content of 20% is present at minimal level in rice husk compared to other biomass source. The ash is high in silica (SiO2) content range, highly porous and light in characteristic, with wide outer surface area (Ajay et. al 2012). The ash of rice husk is statistically proven useful to many industrial applications especially in insulating properties, which is the absorbent (Bronzeoak 2003). With the revenue generated from selling the rice husk ash this would benefits the plant in term of the pay-back period for the capital investment to establish the process plant. Other by-products and their re-utilization proposal are tabulated in Table A.1 (Appendix A). 1.2.4 Sub-bituminous coal supply A significant role is played by coal in power generation with 39% supply in the world’s electricity and it is expected this trend will continue within the coming next 30 more years (The Coal Resource n.d.). The expected growth in coal industry has shown China as one of the largest producer and importer of coal with a total amount of 341 million tonnes of coal in 2013 with expected rise to 471Mt in 2019, consuming more than 50% of the global coal demand (Sadamori 2014). The sub-bituminous coal is generally used for electricity generation, although it has the second lowest energy content, large quantities are found in China 31% Indonesia 9% Bangladesh 7% Vietnam 5% Thailand 5% Myanmar 4% Philippines 2% Japan 2% Others 14%
  12. 12. 5 thick beds near the surface, resulting in low mining cost and correspondingly, lower prices in 70-80 USD/tonne (EIA 2011). Currently, over 4050 million tonnes of coal is consumed globally. It is used in various sectors including the power generation plant, iron and steel production, cement manufacturing and liquid fuel production (The Coal Resource n.d.). According to Sadamori (2014), with a growing rate of 2.1% on average annually, the demand of coal will eventually surpass the 9 billion tonnes threshold in 2050 as one of the highly demanded fossil fuel where the top five producers of coal are China, USA, India, Australia, and South Africa. It is reported that the steam coal production is projected to reach around 5.2 billion tonnes; coking coal 624 million tonnes; and brown coal 1.2 billon tonnes (The Coal Resource n.d.). The global coal production is shown in Figure 1.3 as follows. Figure 1.3. Estimated world coal production from 1985 to 2100 (Hook et al. 2010) 1.2.5 Syngas market Syngas is an extremely flammable transparent and odourless gas with major composition of CO followed by CO2, water, CH4 and H2 (Syngas Mix 2015). Generally, syngas is used to generate power or further refined as feedstock for petrochemical industry. It can be further upgraded to meet specific demands since it is a crucial intermediate resource for hydrogen, ammonia, methanol, and synthetic hydrocarbon fuels production. The composition of H2 to CO2 in syngas can be adjusted with respect to the demand for the syngas mixture (Brar et al. 2012). A number of liquid fuels can be created from syngas, including gasoline, diesel, methanol and other synthetic oils which has been widely used in South Africa (Syngas 2015). It is also used as intermediate for chemical synthesis such as methanol, ethanol, ammonia and methene production which formed a basis for fertilizers, pharmaceutical products and other commercial products. High hydrogen percentage syngas can be chemically converted and
  13. 13. 6 separated into a pure hydrogen stream via the shift reaction. This is summarized in Figure 1.4 below. Figure 1.4. Syngas Usages (Syngas 2015) It is estimated that the syngas compound annual growth rate (CAGR) will surge up to 9.5% between 2015 to 2020 where a total amount of 116,600 MWth of syngas is produced in 2014 and is expected to hit 213,100MWth in 2020 (Rohan 2015). The end use of syngas are classified into a few major application, including chemicals, liquid fuels, gaseous fuels, and power generation. It can be further refined to yield products like methanol, ammonia, oxo- chemical, hydrogen, N-butane, and Dimethyl ether (DME) which have better market price than the revenue generated from syngas sale (Rohan n.d.). Syngas price varied from 100-300 USD/m3 with the capability of generating 3.6 MWh of electricity and 3.5 Gcalh of heat (Syntes 2015). The world primary energy demand of natural gas and oil will eventually spike up to 3000 to 5500 million tonnes in the coming 30 years (Energy Security n.d.). This trend can be observed in Figure 1.5. Figure 1.5. World primary energy demand (Energy Security n.d.) Hence with this preliminary economic anaylsis, the proposed project is achievable with positive price trend and high demand for the product gas. The process plant aimed to produce
  14. 14. 7 syngas at a rate of 0.316 m3/s, for which this 60 % H2 composition in syngas can provide higher efficiency in electricity generation or to further refining steps. 1.3 Raw Materials Sub-bituminous coal and rice husk are chosen as the raw material for co-gasification as they are both readily available in Asia and rice husk is the energy source in thermochemical conversion process such as gasification and combustion directly without processing (Makwana et al. 2015). Rice husk is chosen with consideration of various aspects as shown in Table A.1 (Appendix A). Rice husk particles varied in the range of 0.21 to 0.85 mm which is a suitable size for Circulating Fluidized Bed technology (Gómez-Barea and Leckner 2010). It is also the major by-products from rice milling process and constitutes about 20 % and is not utilized to any significant extent and has great potential as an energy source (BioEnergy Consult 2015). Furthermore, rice husk ash produced from gasification and combustion processes can be used further as supplementary material in cement and ceramic manufacturing process while the biochar produced can be used as soil amendment (Makwana et al. 2015). The use of fossil fuel, coal is reduced by half compared to a typical gasification plant, where the syngas achieved higher carbon conversion which is complimented by coal and rice husk to produce sufficient carbon content in syngas (Mundi n.d. 2015). The storage condition of the raw materials is available in Table A.2 (Appendix A). 1.4 Process Screening The main processes for this plant are gasification and desulphurization, which consists of several alternative technologies. The process screening flowchart is summarized in Figure 1.6 below. Figure1.6. Process screening flowchart For gasification, 4 types of gasifiers, namely the fixed bed updraft, fixed bed downdraft, fluidized bed and entrained bed technologies are compared with respect to their fractional atom process economy, cost, advantages, limitations and various factors as shown in Table Select feed Select gasification technologies Identify type of gasifier design Select desulphurization technologies Select sorbent Validate real plant application 1 2 3 4 2 5 6
  15. 15. 8 A.4 and Table A.5 (Appendix A). The fluidized bed and fixed bed are the most common type of gasifiers used for co-gasification. Fixed bed updraft gasifier is able to handle high moisture and high organic content of biomass while product from fixed bed downdraft gasifier contains low tar and ash content (Bhavanam and Sastry 2011). However, both designs are not feasible for up-scale production (Gasification Status and Technology 2012). Whereas, entrained bed gasifier produce nearly tar-free and low methane syngas but it is not suitable for biomass feed due to its high moisture content (Basu 2013). For fluidised bed gasifier, it excels in mixing of coal and biomass feed, which is applicable to co-gasification plant. Agglomeration of ash by-product on the bed particles might lower the process efficiency (Kern 2012), yet this only causes less impact to entire plant. Therefore, fluidized bed gasifier is selected and the summary is available in Table A.6 (Appendix A). Focusing on the selected technology, there are three types of fluidized bed gasifier that can be designed, namely bubbling fluidized bed (BFB), circulating fluidized bed (CFB) and dual fluidized bed (DFB). BFB and CFB are operated in similar system where the difference is CFB has an extra cyclone which is used to separate syngas and particles and allow the materials will return to the bottom of the gasifier after separation (Makwana et al. 2015). DFB is eliminated due to its complex construction and operation as well as it is relatively more expensive (Puig-Arnavat 2015). CFB is the extension of BFB with cyclones and separators to capture recycle solids to extend solid residence time (Li et al. 2004). This increase the carbon conversion and rate of reaction in the chamber which increase the production of syngas (Gómez-Barea and Leckner 2010). As a result, Circulating Fluidized Bed (CFB) is chosen as shown in Table A.7 (Appendix A) for its high carbon conversion, capability for constant temperature in reactor, compatibility for biomass-coal mixing as well as the minimal ash and slag content in product gas for cost effective and feasible design For gas clean-up technology, desulphurizer is designed to remove sulphur content in raw syngas, in the form of H2S or COS. The sulphur removal is proved to be more effective by applying adsorption process. Adsorption is a surface process, the accumulation of a gas or liquid on a liquid or solid (Chromatography 2014). Table A.8 (Appendix A) demonstrated the comparison of adsorption by solid sorbents and solvents, based on its advantages and limitations. Due to its greater process efficiency and high energy saving, solid sorbent is eventually chosen to undertake the adsorption process (Ke Liu 2010).
  16. 16. 9 Lastly, the comparison of worldwide similar operating plants, based on its development status and product syngas characteristics is shown in Table A.9 (Appendix A). Both Foster Wheeler and Fraunhofer Umsicht plant are using Air-Blown Gasification Cycle, with directed heat under atmospheric pressure, while Uhde uses High Temperature Wrinkler (HTW) gasifier, which is heated under pressurized condition, with high carbon conversion of 98%. Based on the product characteristics, Uhde possessed the greatest potential to produce hydrogen rich syngas, with composition of 30.1% H2 (Renzenbrink 1998). 1.5 Site Selection For this design project, three sites have been considered. They are Samalaju Industrial Park, Sarawak, Malaysia; Jababeka, Cikarang, West Java, Indonesia; and Zhengzhou High Tech Industrial Development Zone, Henan, China. Samalaju Industrial Park is chosen as the proposed plant location after comparison since various infrastructures and utilities are well established in this industrial park and the economical aspect is also favourable as demonstrated in Appendix B. The proposed plant site is illustrated in Figure 1.7 below. Figure 1.7. Proposed site area for plant design (Score 2015) Acceptable utilities cost, availability of proper waste water management, and the presence of various governmental incentives are also some promising factors in choosing Samalaju Industrial Park. By comparing the land price, it is found that the Samalaju Industrial Park is far cheaper compared to the other two and a lower capital cost for the start-up of the plant is possible. Besides that, vicinity of Samalaju Port and other transportation also ease the import and export processes of raw materials and products, especially from China as presented in the earlier market survey. The demand for syngas for power generation and petrochemical Proposed Site Location
  17. 17. 10 industries from industries in Samalauju Industrial Park is also observed in SCORE. It should be noted that although the sub-bituminous reserve is reported to be more in China, the weather in China varies all year round and in extreme winter, that would mean extra cost needed for the heating system in the plant. Since Malaysia is least prone to natural disaster such as earthquake, volcano eruption, typhoon and many more, extra advantages to build the plant in Malaysia itself is preferred. 1.6 Problem Statement In order to solve the alarming issue of rising greenhouse gas emission and to meet the increasing global energy demand for renewable energy of high energy efficiency and minimal environmental impact, the present work critically examines literature on co-gasification of coal and biomass from pre-processing of feedstock to product utilization, and this knowledge is applied in the proposed syngas production plant design. 1.7 Proposed Solution The proposed plant design aimed to decrease greenhouse gas emission with the use of recycled agricultural waste, rice husk as the fuel to co-gasification with coal and steam using the proposed circulating fluidized bed process technology to promote efficiency in a green field site called Samalaju Industrial Park, Sarawak, Malaysia. Moreover, the proposed plant design emphasized on clean gas product utilization with the removal of H2S, tar and ammonia in a recirculating desulphurization loop prior being stored or supplied to other industries. Thus the objectives of this project are to meet market demands by producing approximately 50kT of hydrogen rich syngas annually; to reduce environmental impact and operational risks; and lastly to ensure profit and sustainability of the plant. A sustainable environmental development plant is proposed such that waste such as absorbents, catalyst and char are reutilized (Appendix A) and utilities are co-generated within the plant to generate electricity for renewable energy and ultimately to achieve high energy saving with the use of biomass. The main constraint is the feedstock properties where the source and storage condition of raw materials has to be constant in order to achieve the required product specifications. Another constraint is present in the production rate for which the amount of waste produced per annum is limited with respect to government acts and strict waste management requirement. Lastly, the accessibility, land and safety of the plant provide challenge in plant capacity and growth where natural disaster can impose certain risks to the plant.
  18. 18. 11 2.0 DESIGN METHODOLOGY The basis of design, assumptions, simulation specifications and, the mass and energy balance is presented to design the process plant. The process flow diagram and simulation flowsheet are then developed in this section. 2.1 DesignProcess Description The design criteria of the process plant are highly significant for the development of the simulation, hence the input data and specifications are developed based on critical literature review with a few assumptions applied with proper justifications. 2.1.1 Basis of design The process is simulated using Aspen Plus instead of Aspen HYSYS due to the capability of Aspen Plus to simulate solid feed and later on liquid-vapour phase streams with accurate result. The operating period of the plant is 330 days per year in consideration of time taken for maintenance or start-up work. The property methods, models and general thermodynamic assumptions used in Aspen Plus is tabulated and justified in Table C.1 (Appendix C). For the feedstock of the process design, pre-treatment will not be simulated and the composition of coal and rice husk varies with negligible amount of sulphur for rice husk. The ultimate analysis, proximate analysis and sulphur analysis of coal and rice husk is required as basis for the simulation design in feed specifications as shown in Table C.2 to Table C.4 (Appendix C). Other feeds such as steam, water and oxygen as well as the key input data for major equipments and streams are presented in flowsheet sequence as summarized in Table C.5 (Appendix C). There are a few reactions involved in the process plant, for which these reactions occurred in the gasifier, pyrolysis reactor, desulphurizer, two absorbent regenerators and lastly the water gas shift reactor. The pyrolysis and water gas shift reaction involved catalysts, and some reactions in each reactor happened simultaneously as side reactions. These chemical reaction mechanisms are shown respectively in Appendix C. 2.1.2 Process overview The proposed process flow diagram developed from critical literature review and experts input is shown in Figure 2.1 below with respect to the design basis and assumptions made in
  19. 19. 12 the previous section. A more detailed process flow diagram and the simulation stream table are illustrated in Figure D and Table D.1 respectively, in Appendix D. Figure 2.1. Process flow diagram of co-gasification of coal and biomass plant design Based on the above illustration, the plant consists of four major sections, which are the gasification process, gas cooling or Heat Recovery Steam Generator (HRSG) section, the gas cleaning process, and lastly the water gas shift process. The feed includes rice husks, coal, water, steam and oxygen in different sections whereas the products of the plant are mainly the hydrogen rich syngas and a considerably small amount of sulphur as by-product. Prior the gasification process, the pre-treated uniform sized raw materials (rice husks and coal) are mixed and fed to a dryer (D-100) by using conveyors (CV-100 and CV-101) which are mounted and installed to transport the solid feeds. At the gasifier (G-100), both feeds are co- gasified at temperature of 700ᴼC and pressure of 32.04 bar with continuous steam input generated from the following HRSG section. The gasification process utilized steam only as the gasifying agent because the use of air in gasification could result in undesired nitrogen dilution thus lowering its value (Boharapi, Kale and Mahadwad 2015). Hence the proposed gasification without air or oxygen input has the advantage of higher hydrogen element yield, higher product value and improved resource utilization in the form of steam used in the cooling sections. A primary tar cracking process is involved in the gasifier where one of the gasifying product, char is accumulated on the bed in a porous form to reduce the tar level in the presence of steam (Fjellerup et al. 2005). The raw syngas exit from the gasifier and it is fed into a cyclone (CY-100) to remove ash and the remaining char components, in illustration of a full fluidized bed gasifier system where the residue remains are removed from the bottom of an actual gasifier (Boharapi 2015). The solid-free raw syngas then entered the cooling section.
  20. 20. 13 The HRSG, which covers the cooling section, features a quencher, a superheater heat exchanger, a medium pressure (MP) and a high pressure (HP) steam cooler respectively, compressor, a series of heaters and a steam turbine. The raw syngas flowed through a quencher (Q-200), a superheater (HX-100), C-200 and C-201 coolers before half of this mixture is recycled and compressed back to Q-200 to quench the gas and maintain the temperature difference between hot and cold stream prior entering the wet scrubber. The recirculation of the raw gas enables heat to be recovered where mechanical work is produced in the gas compressor (CO-200). The processed, pure water feed is utilized for the generation of power from the steam turbine (STUR-400) and heater series where steam is formed for gasification process. The utilities are summarized in Appendix D with detailed calculation. At the subsequent gas cleaning process, the raw syngas is mixed with deaerated water in the water scrubber (SC-200) at 144ᴼC and 26 bar in order to limit tar, ammonia and the steam flow rate from the total product composition (Botha 2012). The wet scrubber scrubbed secondary tars to a pyrolysis reactor (R-200) at the condition of 120ᴼC and 20 bar where tar cracking reaction occur in the absence of oxygen and it is assumed that the secondary tars are fully converted to raw syngas. As desulphurization requires high cost and complex design to cool the syngas to certain temperature, the HRSG has benefitted the plant such that the power generated from STUR- 400 and CO-200 have driven a heat-integrated system in preparation for gas cleaning treatment (Gupta et al. 2001). Desulphurization (R-300) took place at 450ᴼC and at the pressure of 26 bar using absorbent (Fe2O3) generated from the regenerators (R-301 and R-302) in a recirculation loop. Molten sulphur is condensed out continuously in the SO2 regenerator (R-301) from recirculating SO2 gas stream generated from the O2 regenerator (R-302). The sulphided absorbent is fed into the multistage reactors and it is heated (H-300) to 600ᴼC to form the regenerated sorbent, where subsequently this partially regenerated sorbent is passed into R-302 and oxygen is added to the regeneration gas for maximum conversion before it is cooled (C-300) and fed back into R-300. The recirculation loop allows clean syngas to be recovered using a condensing separator (S-300) and this clean gas with hydrogen 50 vol% proceeds to its last cleaning step. The catalyst packed reactor (R-400) is operated at temperature 200ᴼC and pressure 15 bar where the water gas shift reaction occurred to produce more hydrogen, which is a final greener and cleaner syngas product with 60 vol%, in accordance with customers demand.
  21. 21. 14 2.2 Material and Energy Balance Mass and energy balances are performed in order to compare the result from theoretical methodology with the result obtained from Aspen Plus simulation. The methodology of the material and mass balance is in Table D.6 (Appendix D) whereas for energy balance is in Table D.8 to Table D.14 (Appendix D) for respective equipment. For mass balance, the small error percentage between the result from simulation and manual calculation is due to difference in some properties used in simulation and manual calculation whereas for energy balance case, it is due to a few thermodynamic assumptions made shown in previous section. A summary of result for comparison of material and heat balance between manual and also Aspen Plus calculation is shown in Table D.7, Table D.3 to Table D.5 (Appendix D). 2.3 Heat Integration Heat integration, also known as energy integration or pinch analysis is a technique used for minimizes energy consumption and maximizes heat recovery in the plant. Heat energy network (HEN) is used to indicate the calculation of minimum heating and cooling requirements which reveal significant energy savings. A more detailed step-by-step approach is shown in detailed in Appendix E. The methodology is summarized in a flowchart in Figure 2.2 below. Figure 2.2. Flowchart for energy integration workflow The main objective to perform energy integration is to improve the energy efficiency of the co-gasification plant which includes heat exchanges, heaters as well as coolers to heat and cool the process streams to specific desired temperatures. Reactor such as pyrolysis reactor, Aspen Energy Analyzeris used to obtain the composite curve and recomendedHEN design. The inlet andoutlet temperature, enthalpy, and heat capacityflowrate (MCp) are obtained. Shiftedtemperatureis calculatedby using ∆𝑇 𝑚𝑖𝑛 = 10℃ Utilities in streams is calculatedby using∆𝐻 = 𝐶𝑃𝐻 − 𝐶𝑃𝐶 × ∆𝑇 Heat cascade is performed via the temperature interval. Program table algorithm (PTA)is carriedout. The pinchtemperature is obtainedby indicatethe largest heat deficit,which in this case is 600.18℃. Total minimum heating requirement, 𝑄 𝐻𝑚𝑖𝑛 and minimum cooling requirement, 𝑄 𝐶𝑚𝑖𝑛 is obtained. Above pinch temperature andbelow pinch temperature is cauculated. Heat exchanger network design (HEN) is carried out.
  22. 22. 15 desulphurizer and water gas shift reactor which require duty are taken into consideration. The total heat required before and after heat integration is compared in Table 2.1. Table 2.1. Energy saving from hot and cold utilities Detail Cold Utilities (MW) Hot Utilities (MW) Before Heat Integration: 241.87 44.54 After Heat Integration: 123.05 44.54 Total Heat Reduced: 118.82 0.00 Total Saving (%): 49.13 0.00 The energy saving are 49.13 % and 0 % for hot and cold stream respectively. As the cooling water used to cold down the ash is recycled repeatedly which brings to only small amount of water is required with small duty (SOLEX 2015), which is insignificant when compared to the hot utilities to heat up the water in order to generate the steam for gasifier. Hence, this indicated the 0 % of energy saving in hot utilities. 2.4 Process Optimization The process optimization is carried out with the aim of reducing utilities cost as the capital cost is assumed to be constant since the equipment sizing remain unchanged. The outcome from the heat integration from previous sub-section is applied. The utilities cost is tabulated in Table F.1 (Appendix F) indicating the total cost of utilities before and after process optimization where it is shown that the total utilities cost is reduces from RM 296 million/year to RM 51 million/year, indicating a saving up to 82.7 %. Another objective function of this process optimization is the syngas product hydrogen, H2 yield as it is an important factor to achieve a higher H2 yield in relation to the reduction in utlities cost from heat integration.The variables that are manipulated includes equipment with possible exergy losses such as mixer, gasifier, reactors, heat exchangers and heaters or coolers, for which their parameters are adjusted , including flow ratio, exit temperature, operating pressure feed ratio and fractional coversion of reactions. The minimum approach of heat exchangers can only be reduced to a certain range for an efficient and feasible design, whereas the H2/CO ratio is also increased subsequently, due to the unavoidable increase in H2 and reduction in CO. Again, this ratio specification is based on the customer demand on the type of syngas for different industries. Lastly, the safety parameters such as flammability point and storage pressure of the product is also maintained at specific range. The optimized parameters are shown in Table F.2 (Appendix F) with respect to the objective, manipulated variable and constraints.
  23. 23. 16 Thus a cost saving of 82.7% is achieved, with an increase in hydrogen yield of 12.9% from 82.3% of base case to 92.9%. The optimized flowsheet after heat integration and flowsheet optimization is obtained as shown in Figure 2.4 below. A detailed PFD of the optimized case simulation diagram and its flowsheet is available in Figure F.1, Figure F.2 and Table F.3 respectively (Appendix F). Figure 2.4. Process flow diagram after optimization 2.5 Process Control The proposed process control and instrumentation system aims to reduce variability, increase efficiency and ensure safety (Rangajah, 2012) while meeting the product specifications and policies. Instruments and valves are installed for reliability and robustness, for which the process control philosophy is established based on Luyben’s Top Down approach (Luyben and Luyben 1997), following the steps below: - Define operational objectives - Identify degree of freedom and operating condition - Identify and select primary controlled variables - Select the location of Top-down Production Management, TPM The H2/CO ratio and syngas yield are maintained using flow, ratio and composition controllers so that a hydrogen-rich syngas product is processed at an approximate rate of 162 tonne per day. Moreover, instruments such as alarms and indicators are useful when a failure is registered within a specific safety margin where technicians are called in for action. Lastly, majority of the plant equipment and vessels pressure and temperature are regulated with pneumatic signal transmission for effective and immediate response, where in overall a total of 39 control valves are installed. The piping and instrumentation diagram and the plant wide control philosophy are shown in Figure G and Table G respectively (Appendix G).
  24. 24. 17 3.0 PROFITABILITY ANALYSIS To investigate the profitability viability, the equipment schedule and pipe specifications are first specified as shown in Appendix H followed by calculation for equipment sizing and costing (Appendix I) which covers each equipment methodology with assumptions made in Appendix J. From calculation, the total capital investment for the gasification plant is estimated to be RM 2,282,298,569.24 as shown in Table J.1 (Appendix J). The capital and operating cost are then calculated and three economic scenarios are developed for analysis. 3.1 Capital and Operating Cost Investment The Chemical Engineering Plant Cost Index of 2015, often abbreviated as CEPCI, is utilized to estimate the cost index for capital investment of the co-gasification plant. According to Timmerhaus et. al (2003), the direct and indirect costs of the overall plant including the investment costs of land, site development, battery-limit facilities, and auxiliary facilities is part of the capital cost. It is found that the direct cost, which covered purchased equipment, installation, piping, instrumentation, controls, electrical system, building and service facilities cost around RM 1,370,286,616.13 whereas the indirect cost, which is the summation of engineering and supervision, construction, contractor and contingency fees of this plant is RM 571,708,985.54. The cost summary and calculation of the direct and indirect production cost of syngas calculation is in Table J.2 (Appendix J). 3.2 Economic Scenario Analysis: Base, Best and Worst Case The profitability analysis of the syngas production plant is investigated in three case scenarios which are the base, best and worst case to determine impact of the fluctuation of raw material cost to the overall profit of the plant. From Appendix J, the operating cost for a yearly basis are RM 1,101,767,028.21 (best), RM 1,236,355,282.89 (base), RM 1,525,383,537.57 (worst), as shown in Table J.3. The cumulative discounted cash flow in Figure J.1 is derived from the sensitivity study of the discounted cash flow rate shown in Table J.4 to Table J.6 for each of the scenario within a lifespan of 25 years. The bank loan payment schedule for each scenario is tabulated in Table J.7 to Table J.9 and illustrated in Figure J.2 to Figure J.4 respectively. The total annualized cost for the best, base and worst scenarios are RM 3,527,888,385.34, RM 3,668,196,640.85, and RM 3,969,508,596.35 respectively where the best case scenario gives the most economic advantages among the others as shown in net profit analysis (Figure J.5). The payback period for base, best and worst case is calculated as 0.55, 0.93 and 3.12 years respectively with the shortest profit generation duration and highest revenue for best case shown in Figure J.6 and Figure J.7.
  25. 25. 18 4.0 RISK ASSESSMENT The vulnerability of the plant is assessed in this section in terms of economic, safety and environmental aspects. A hazard and operability study (HAZOP), and SWOT analysis are presented in this section as well. 4.1 Economic Aspect The profit of the plant is dependent on the market and customer demand where the best, worst and base case scenarios can be referred such that thorough case study can be done to prepare strategies for worst scenarios. Meanwhile, the impact of risk, hazards or catastrophe events is highly interrelated to the business operation where regulations and proper planning of the plant operation are important to keep the reputation and prevent financial loss. Thus, a complete hazard identification, vulnerability assessment and impact analysis is important to reduce or mitigate potential risk with effective strategy at high priority. This is further discussed in the following section. 4.2 Safety Aspect and HAZOP Assessment Proper plant layout is important for the prevention of the occurrence of catastrophic event. Proposed plant layout was divided into three zones (safe, moderate and dangerous) according to safety level as presented in Appendix K. By referring to the plant layout, green zone is the administrative area, bottom yellow zone is for storage tanks, top yellow zone is the waste water treatment plant and utilities system and lastly red zone is the process plant and flare gas system area. Area allocation is based on prevailing wind direction and the safety distance of 3.5 m between each equipment is planned to prevent terrific loss and enable ease of control when severe accident occurs. Moreover, administrative zone which consists of offices and canteens in which most personnel will be working at will be situated furthest away from the production and storage area, where in the case of control room it is designed with special barriers. This is to ensure that in any case of incidents such as toxic gas release, explosion or pressure burst at red zone area it will have minimal impact to the personnel (Health and Safety Executive 2015). Various safety features are included in the design of the building such as proper emergency exit plan, multiple exit doors for heavy flow area, fire resistant materials for room construction, fire detection alarm, operational links between operators, proper temperature and airflow control. Sprinkler store room, water tanks are also situated near the production
  26. 26. 19 area for ease of fire extinguishing in case of any emergency while assembly points are available at emergency evacuation. Operation-wise, it is crucial that proper commissioning is done follow by start-up process where all the installed equipment in a plant is thoroughly checked to ensure the equipment can work properly prior to plant operation (Integrated Service Solutions 2015). Various functional checks will be done on the equipment and any defects are to be recorded and resolved. Once all the commissioning activities are done, commissioning team will have to issue RFSU (Ready for Start-Up) certificate so that start-up activities can be initiated. To ensure the integrity of the equipment and the efficiency of whole operations, maintenance has to be done regularly during the shutdown. This phase will comprised of proper inspection on equipment and repair of any faulty equipment as well as control system. All of these phases are important throughout the whole life cycle of the co-gasification plant to ensure effective operations, continuous production of syngas, prevent any incident, and for the occupational health and safety of all the personnel. The detailed activities involved in each phase are further elaborated in Appendix L. 4.3 Environmental Aspect Preliminary environmental impact assessment is crucial in determining the possible activities that could cause harms to the environment, safety, social aspects as well as the company’s benefits. Throughout the lifecycle of the plant, various activities might have caused adverse impact on the environment such as pollution or potentially harm the surrounding community. Thus, a preliminary environment impact analysis as shown in Table M.1 (Appendix M) is developed to identify possible accidents and their impacts with suitable mitigation measures while a plant contingency plan with safety measures during emergency and safe handling plan for hazardous materials is presented in Table M.2 and Table M.3 (Appendix M) respectively. A HAZOP study is presented in Table M.4 (Appendix M) where any possible deviations of parameters such as temperature, pressure, flow, level and many more from normal conditions are identified before a well-planned safeguard and recommendation actions are prepared. These considerations can make a big difference during operation as it is crucial that all the equipment are equipped with safety features and undergone scheduled maintenance to reduce or eliminate any potential risks.
  27. 27. 20 5.0 CONCLUSION The implementation of biomass gasification as alternative feed to substitute fossil fuels usage in energy generation is applicable. Based on the results generated, it is proven that the gasifying biomass with coal will raise the efficiency of the propose gasification plant, and reducing the greenhouse gases emissions. Utilizing both the feedstocks, sub-bituminous coal and rice husk at 1:1 ratio to achieve high gas yield, low tar and char yield, as well as high thermal efficiency with effective HRSG and desulphurization gas cleaning technology that promotes sustainable development in environmental, economics, safety and resources aspects is achievable. The increase in energy saving after optimization are mainly a result of reduction of substances that require energy to be removed from the syngas, especially those with sulphur content. It is also observed that the water scrubber play an crucial role in gas clean-up system, increasing the levels of biomass with less fly ash as well as slag output. Material and energy balance calculation performed had proved the design feasibility followed by heat integration and process optimization with the optimized process flow diagram shown in Appendix F (page 69). The results of the sensitivity analysis demonstrate that feedstock cost was the most sensitive cost factor on unit costs manipulating the economic analysis of the overall process plant for the best, base, worst case scenarios. In summary, the proposed plant design is capable of producing 50 kilo-tonnes of hydrogen- rich syngas annually with total annualised cost (TAC) of RM 3,527,888,385.34 and a payback period of 0.55 years with energy saving up to 82.7%. Recommendation Despite much research is being conducted in this field, the co-gasification of rice husk and coal has not yet been fully explored. The tar evolution profile from the co-gasification of rice husk and coal requires further investigation to customize the operating system and removal system. Along with this, the catalyst used can also be a research opportunity for the future as it affect the production rate of the syngas, as well as the efficiency of the overall process plant. More economic analysis methods can be conducted for results comparison with the propose method, the purpose is to further validate the values obtained with proper justification for the method chosen.
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  35. 35. 28 APPENDICES Appendix A: Product, Raw Materials and Process Technology Evaluation Prior process screening, the type of agri-waste used for gasification is considered carefully. Table A.1 is developed as shown below with respect to palm oil kernel shell, sugarcane and rice husks. Table A.1. Comparison of different biomass resources Type of biomass Rice Husk Palm Oil Kernel Shell Sugarcane Straw Physical Properties - 1 ton Rice Husk is equivalent to 410- 570 kWh electricity - Calorific value = 3000 kcal/kg - Moisture content = 5 – 12% - Heat Energy/ Calorific Value: > 4.000 kcal/Kg - Inherent Moisture: < 20 % - Ash content:< 15% - Size: 4-20mm - Foreign materials (By visual): < 2% - Gross heat = 18.870 kcal/kg - Fiber content = 65 % - Pith cells = 25 % - Water soluble = 10 % - Ash content = 2.4 % - Size = 1.5-2 mm Chemical Properties - C: 45.8 %; O: 47.9 %; H: 6.0 %; S: 0.0 % N: 0.3 % - C: 63.02 %; O: 36.04 %; Al: 0.43 %; Si: 0.17 %; P: 0.17 %; K: 0.17 % - C: 51.71 %; H: 5.32 %; O: 42.64 %; N: 0.33 % Advantages - Can be directly used in gasification. - Low moisture content - Inexpensive (waste from rice mill) - -Asia has the highest rice husk production - Can be stored at open space - Blends well with coal dust - Inexpensive inner logistics - Non-absorbility - Inexpensive (waste from sugarmill) - Suitable for fluidized bed processing. Limitations - Large amount of rice husk is required. - Resistance for crushing - Need to be processed before being used for gasification - Limited supply as sugarcane only produced for 6 months of the year. - Need to be processed before being used for gasification Reference Mundi n.d. (2015); Vélez et al. (2009); BioEnergy Consult (2015) Biofuel Resources (2015); BMC (2015); Dagwa, Builders and Achebo (2012) Ripoli (2000); Hassuani (2005) The re-utilization or disposal of the ash, char and tar by-products is shown in Table A.2. Ash can be encapsulated, which is added or bounded into concrete to enhance concrete in terms of workability and durability (Business Recycling 2015). It can be used to fill abandoned mine and unpaved roads as well. Char can be recycled into biomass pyrolysis process as well as reused as absorbents and carbon supported catalysts, providing additional value added products from the bio refinery (Kastner2015). On the other hand, Tar Steam Reforming (TSR) process can convert high molecular weight hydrocarbon of tar into smaller gas products including CO2 and H2 (Vivanpatarakji 2014). It can be recycled to tar cracking process as well, for further treatment into reusable products.
  36. 36. 29 Table A.2. Utilization of by-product Residues Ash Char Tar Reutilization / Disposal - As a partialreplacement for the sand, limestone and cement content in concrete. - Structural fill for abandoned mines - Top layer for unpaved roads - Recycled in biomass pyrolysis process - Can be reused as tailored absorbents and carbon supported catalysts - Sent to Tar Steam Reforming (TSR) to form smaller gas products - Recycled into tar cracking process to form reusable products References Southeast Coal Ash Waste (2013), EPA (2015), Business Recycling (2015) Kastner (2015), James (2013) Rabou (2009), Vivanpatarakij (2014) Table A.3. Storage and transportation for feedstock and products Aspects Sub-BituminousCoal Rice Husk Syngas Storage - Covered storage yards - Continuous water sprinkling systemon the roof - Covered with permanent weather shed roofing and side walls - Covered storage yards - Fixed water pipenetwork system - Store in syngas storage tank with international standards such as ASMESection VIII Div 1, 2, PD 5500, AD Merkblatter and Codap 2000 - Store in temperatureless than 52 0 C equipped - Storage tank is safety valves, level gauge, pressureand temperature gauges and other safety accessories - Storage tank is located away from heat source and open flames. Transportation - Tarpaulin cover before loading the coal onto the track manually - Cover using nylon shed to avoid spilling - Loaded into trucks manually using shovels - Cover using nylon shed to avoid spilling - Delivered using stainless steel pipeline with weatherproofed coating Reference G. Okten (2015); Mehrishi (2012) G. Okten (2015); Mehrishi (2012) Corporation (2000); Tanks (2015) Table A.4. Fractional atom economy calculation i Sum vik Mi viMi viMi*SF (ton/day) Price ($/ton) Price*viMi*S F ($/day) C -4 12.01 -48.04 -39.21 80.17 (Vélez et al. 2009) -3143.47 H2O -2 18.02 -36.04 -29.42 0.41 (Baliga 2014) -12.06 CH4 -5 16.04 -80.20 -65.46 139.3 (C.H. Wong et al. 2011) -9118.58 O2 -5 16.00 -80.00 -65.30 35 (Muller 2007) -2276.05 CO 6 28.01 168.06 137.17 600 (Clean Technica 2014) 82302.00 H2 12 1.01 12.12 9.89 1200 (ManitobaEnergy Development Initiative 2003) 11868.00 CO2 3 44.01 132.03 107.76 10.15 (Lucklow et al. 2013) 1093.76 Fractional Atom Economy = 168.06+ 12.12 −(−48.04 − 36.04 − 80.20− 80) = 0.7376 Sum with CO2 ($/day) 80713.61 Scale Factor, S = 50000 𝑡𝑜𝑛𝑛𝑒𝑠 𝑦𝑒𝑎𝑟 × 𝑦𝑒𝑎𝑟 340 𝑑𝑎𝑦𝑠 168.06 + 12.12 = 0.8162 Sum without CO2 ($/day) 79619.84 Table A.5. Calculation of raw materials gasification process economy Feedstock Carbon (C) Composition Average Price (MYR) Average Price × Carbon Composition Sub-bituminous coal 0.824 ( 472 − 285 2 ) + 285 = 378.50 0.824 × 378.50 = 311.88 (Vélez et al. 2009) Biomass (rice husks) 0.458 ( 50 − 20 2 )+ 20 = 35 0.458 × 35 = 16.03 (Vélez et al. 2009) Total Price for C/tonne 311.88+ 16.0 = 327.91 𝑀𝑌𝑅 ≈ $ 80.17
  37. 37. 30 Table A.6. Summary of comparison between various types of gasifiers Criteria Fixed bed updraft gasifier Fixed bed downdraft gasifier Fluidized bed gasifier Entrained bed gasifier Process Description - Also known as counter-current or counter-flow gasification - Feed is introduced at the top of gasifier while air is injected at the bottom - The product syngas leaves at the top - Divided into drying, pyrolysis, gasification and oxidation zones - Heat from oxidation and gasification provides energy for drying and pyrolysis - Also known as co- current gasification - The fuel (biomass and coal mixture) travel down by gravity and exit at the bottomwith air injected at the body - The fuel beds are divided on various grates for different processes. - Process includes drying, pyrolysis, oxidation and reduction with air feed. - A bed of dry, solid feedstockwhich comprise of coal and biomass mixture is seeped with gasifying agent such as steam or air through the pores at the bed where solid will be suspended in the fluid for the gasification reaction - Main processes fast pyrolysis, reactions of volatile matters and gasification of char with steam and 𝐶𝑂2 - Powdered coal and biomass mixture fed with gasifying agent from the top. - Combustion will be carried out at the top with the turbulent flame burning mixture with very high temperature and provide the condition for fast coal conversion to produce high quality syngas. - The ash from combustion will melt at the gasifier walls and be discharged as molten slag. Operating conditions - 600 ºC to 1000 ºC - Approximate 0.1 MPa - Gasifying agent: air - Capacity of 20 to 2000 kW - Gasifying agent: air - 800 ºC to 1000 ºC - Operate at vary coal ratio - 0.10 ≤ biomass percent ≤ 0.50 - The existing co- gasification plant used maximum 10% biomass in industrial scale. - Gasifying agent: steam or air - More than 1000 0C. - Endothermic gasification reaction will reduce the temperature to about 800 0C. - Gasifying agent: oxygen Cost Low cost with simple design Low cost with simple design Expensive unit and expensive to operate as high temperature is required Expensive unit and expensive to operate as high temperature is required Advantages - Able to handle high moisture and high organic content of biomass - High thermal efficiency - Small pressure drop - Product gas has acceptable calorific value with low tar and ash content - Simple and proven scheme - Suitable for biomass with low moisture - High overall carbon conversion - Uniform temperature throughout reactor - Excellent mixing of coal and biomass - Insensitive to size of feed solid - Loss of carbon due to fine chars escaping with product - Formation of slag is minimal and can remove stray ash easily - Suitable for up-scaling - Suitable for most coal types - Can destroy tar easily and produce nearly tar-free and low methane syngas - Almost 100 % carbon conversion - Ash is produced as slag
  38. 38. 31 Table A.6. Summary of comparison between various type of gasifiers (continued) Criteria Fixed bed updraft gasifier Fixed bed downdraft gasifier Fluidized bed gasifier Entrained bed gasifier Limitation - Consists high level of tar: 10 to 20% by weight in product syngas - Extensive gas clean- up required to remove impurities - Poor reaction capability with heavy gas load - Not suitable for up- scaling - Low carbon conversion when uneven gas distribution occur - High exit gas temperature with lower product efficiency - High residence time of solids with low gas velocity - Restricted scale up potential due to 250 kW capacity limit - Low ash melting point of biomass result in agglomeration and stick to bed particle - Not suitable for small scale. - Complicated to operate. - Not suitable for biomass due to its high moisture content - Alkali compound in biomass can corrode the gasifier refractory or metal lining - Require fine fuel due to short residence time where biomass pulverized slower - Require large amount of O2 - Require high temperature References Bhavanam and Sastry (2011); Gasification Status and Technology (2012) Gasification Status and Technology (2012); Bhavanam and Sastry (2011) Long (2011); F. Velez (2008); Chapter 8; Fermoso; Kern (2012) Basu (2013); Ogi et al. (2013) Table A.7. Summary of different type of fluidized bed gasification processes Criteria Bubbling Fluidized Bed (BFB) Circulating Fluidized Bed (CFB) Dual Fluidized Bed (DFB) Operating system - Oxygen or steamis blown upwards through the fine inert material bed at the bottomof the gasifier with a high velocity which enough to agitate the material. - Biomass that is fed from the side of the gasifier will be mixed, combusted and formed syngas which will leave from the top of the gasifier - Air, oxygen or streamis blown upwards with relatively high velocity to suspend the material throughout the gasifier. - Biomass that is fed from the side of the gasifier will be suspended,combusted or reacted to form syngas.. - A cyclone is used to separate syngas and particles. The materials will return to the bottomof the gasifier after separation. - Biomass is fed into the BFB/CFB gasifier and be converted into nitrogen-free syngas charby using steam. - Air is fed into the combustor and combustion of char and accompanying bed particles is carried out. - The hot bed particles are then fed back into the gasifier and act as the source of indirect reaction heat. - Cyclone in CFB chamber will separate the syngas Operation conditions - Operates with lower velocity (0.5-2 m/s) to maintain fuel:fluidization gas ratio - Operates below 900 0C to prevent ash melting and sticking - Can be pressurized. - Operates with higher velocity (2-5 m/s). - Has higher fuel flow rate. - Operates below 900 0C to prevent ash melting and sticking. - Can be pressurized. - Operates below 900 0C to prevent ash melting and sticking. - Can be pressurized. Advantages - No clinker formation - Low electric power consumption. - High fuel flexibility. - Good scale-up potential, mixing, gas-solid contact. - Product gas with low tar content. - Low feedstockinventory. - High fuel flexibility - Allow in-bed catalytic process - High carbon conversion and rate of reaction - Ease of operation - Good temperature control - Can operate when loads are lower than design load. - Allow in-bed catalytic process - Good gas-solid contact and mixing - Suitable for high specific capacities (>1 MW) - Good scale-up potential.
  39. 39. 32 Table A.7. Summary of different type of fluidized bed gasification processes (continued) Criteria Bubbling Fluidized Bed (BFB) Circulating Fluidized Bed (CFB) Dual Fluidized Bed (DFB) Limits - Carbon loss with ash - Product gas has high particulates content. - Product gas has moderate tar content and high particulates content. - Complex construction and operation. - Pre-cleaning of gas is required. - Product gas with moderate tar level. - Low efficiency. References Makwana et al. (2015); Gómez-Barea and Leckner (2010); E4 Tech (2009); Gómez-Barea and Leckner (2010); Puig-Arnavat, Bruno and Coronas (2010); E4 Tech (2009); Puig-Arnavat, Bruno and Coronas (2010); E4 Tech (2009); Table A.8. Evaluation on various desulphurization process technologies Criteria Adsorption by solvents Adsorption by solid sorbents Descriptions Required solvents characteristics: - Sufficient sulphursolubility or absorption capacity - Higher selectivity for sulphur - Able to be regenerated or recycled - Stable, low corrosion and low reaction heat - Simple recovery of absorbed sulphur - Conventional cold gas clean- ups’temperature reduction is not energy efficient - Hot gas clean-up is developed as an alternative method which operating under high temperature - Major sorbents are metal oxides Solvents / Sorbents Chemical solvent - Methyldiethanolamine (MDEA) Physical solvent - Selexo Sorbent - Zinc Oxide (ZnO) Advantages - Higher selectivity for H2S and CO2 - Higher solution capacity - Less corrosive - Thermally and chemically stable - Sparingly miscible with hydrocarbons - High selectivity for H2S and COS over CO2. - Also remove other contaminants such as CS2, HCN and more. - no chemical reaction and degradation. - Higher thermal and chemical stability than chemical solvents - Low vapourpressure resulting in low solvent losses. - Thermally and chemically stable. - Higher process efficiency achievable without syngas cooling and removal of water from the syngas - Sour water treating is not necessary - Elimination of “black mud” (ash – char – water mixture) produced in quenching or scrubbing process - Solid sorbents are usually less toxic and corrosive Limitations - Selectively removes H2S resulting in much CO2 unabsorbed - Proprietary additives are required in MDEA solution to enhance the capability of CO2 removal - More expensive than other amine solvents - Losses of hydrocarbons due to coabsorption - Refrigeration sometimes required, resulting in additional cost and complexity - Absorption at high pressure is preferable for high absorption capacity - Removal of mercury in syngas becomes difficult due to temperature rise - Presence of H2O is proven to have negative effect on sorption performance of ZnO sorbent - Removal of other contaminants such as HCN is difficult using current developed sorbents - Degradation of sorbents during the regeneration process References Kothandaraman (2005) Olov Öhrman (2010) Ke Liu (2010)
  40. 40. 33 Table A.9. Summary of similar operating plant with CFB technology Criteria Foster Wheeler Uhde Fraunhofer Umsicht Technology description - Air-Blown Gasification Cycle (ABGC) - Direct heated CFB under atmospheric pressure - Circulating-bed solids are combusted and supply heat for mostly endothermic reactions - High Temperature Wrinkler (HTW) gasifier - Direct heated CFB under pressurized condition (10 or 25 bar) - Air/Oxygen and steam blown - Carbon conversion >98% - Air-Blown Gasification Cycle (ABGC) with catalytic gas treatment - Direct heated CFB under atmospheric pressure - As gasifier in Biomass Heat & Power Plant (BHPP) - 26-29% of electrical efficiency Development status - 4 commercial gasifiers were built in1980s - Coal power plant in Lahti, Finland uses similar gasifier since 1998 - A similar plant was built in Belgium which the moisture of feedstocks can vary between 20-60% - Proven to be technically feasible after the testing on several demonstration plants in 1980s - 30 bar HTW gasifier are available for IGCC plant of either 600MWe (oxygen/steam) or 400 MWe (air) - A 400 MWe HTW plant was built in Vresova, Czech Republic in 2002 - Pilot plant was commissioned in 2002 and succeeded under uninterrupted operation, producing almost tar-free gas - Demonstration plant with thermal capacity of 5 MW was planned in late 2002, yet failed to establish because certain conditions were unfulfilled Syngas characteristics - 5-17 vol% of H2; 21-22 vol% of CO; H2/CO ratio = 0.74; 10-11 vol% of CO2; 46-47 vol% of N2 - No syngas cleaning required - 30.1% H2; 33.1% CO; H2/CO ratio = 0.91; 0.03% of H2S; 0.4% of N2, 90 ppm NH3; 770 ppm of C6H6; 5.7% methane - Syngas cleaning by warm gas filtering - 18 vol% of CO; 14 vol% of H2; H2/CO ratio = 0.78; 16 vol% of CO2; 10 vol% of H2O; 39 vol% of N2; 3 vol% of methane - Less than 50mg/Nm3 of tar - Syngas cleaning by hot gas catalytic tar reforming and fabric filtering References Amec foster wheeler (2015); Horst Hack (2013) Renzenbrink (1998); E4 Tech (2009) Harasek (n.d); E4 Tech (2009)
  41. 41. 34 Appendix B: Process Plant Site Selection Table B. Comparison for Site Selection Factors Site 1: Samalaju, SCORE, Malaysia Site 2: Jababeka, Cikarang, West Java, Indonesia Site 3: Zhengzhou High Tech Industrial Development Zone, Henan, China Size of Industrial Area More than 50 ha of land, approximately 62km from Bintulu city (SCORE 2015) 40ha of land area (Jababeka 2014) 60ha Land price USD 15/𝑚2 (MIA 2009) USD 196.57/𝑚2 (Deutsche Bank 2015) USD 54/𝑚2 Climate /Weather Year-round hot, humid and wet weather. No major extreme weather. (World Guides 2015) Moist tropical climate with abundant rain and high temperatures (Global Rice Science Partnership 2012). Risk of earthquake and volcano eruption (News Track India 2015) Monsoon climate with a hot summer and a cool winter (Global Rice Science Partnership 2012) Availability and supply of raw materials Sub-bituminous coal: obtained from Merit-Pila mine at upper reaches of Rajang River (Pui 2008) Rice husks:Paddy residues Bernas Bintulu (Bernas 2015) Sub-bituminous coal: Coal supply from Cigading International Bulk Terminal Rice husks: Paddy plantation from West Java and import from Thailand (Global Rice Science Partnership 2012) Sub-bituminous coal: Henan Energy and Chemical Industry Group Co. Ltd. Rice husks: Rice production in Henan. (Global Rice Science Partnership 2012) Else, the rice can be obtained via ZhengZhou Commodity Exchange. Demand of product -Electricity generation to supply in Sarawak. -Bintulu LNG Complex to be further refined as feedstock. The syngas produced can be used to power electricity in Java. (Rawlins 2014) The syngas can be further refined to generate electricity to be supplied in factories in ZhengZhou such as Honour Trust Co Ltd and Henan Anfei Electronic Glass Co.Ltd. (KPMG 2008) Transport facilities -Trans-Borneo Highway (2,083 km) - Samalaju port (SCORE 2015) -Easy access to Bekasi-Cikampek toll-road. -Cikarang Dry Port is located in Jababeka Industrial Estate. It is the extension of Tanjung Priok International Seaport for import and export purposes.(Jababeka 2014) Railway: Beijing-Guangzhou Railway and Lianyungang China Lanzhou Railway Port: Lianyungang pPort, Yangshan Port, Shanghai Port (Hong Kong Trade Development Council 2015) Availability of labour Cheap labour available Minimum wage of RM 800 monthly. USCORE Project develop human capital for SCORE (Chemsain Konsultant Sdn. Bhd 2010) Cheap labour available. Minimum wage of Rp 2 700 000 monthly (Wage Indicator 2015) Cheap labour but lacks high-tech talent (Hong Kong Trade Development Council 2015)
  42. 42. 35 Table B. Comparison for Site Selection (continued) Factors Site 1: Samalaju, SCORE, Malaysia Site 2: Jababeka, Cikarang, West Java, Indonesia Site 3: Zhengzhou High Tech Industrial Development Zone, Henan, China Utilities and Services Inexpensive electricity supply from Bintulu CCGT, Sarawak Energy (Sarawak Energy 2015) 130MW power supply by PT Bekasi Power (Jababeka 2014) 1000MW power supply from Henan ZhengZhou Power Supply at price of USD 0.1/kWh, Water resources from Yellow River. (Hong Kong Trade Development Council 2015) Waste Disposal Samalaju Water Treatment Equipped with two water treatment plant and two waste water treatment plant. (Jababeka 2014) Treatment available for sewage and solid waste. (KPMG 2008) Geographica l condition Located strategically south of the booming North Asian markets, Japan, South Korea, Australia and India. (SCORE 2015) Biggest industrial estate in Southeast Asia with investments from various foreign companies Lies in the middle and lower reaches of Yellow River and thus suitable for various industries. (KPMG 2008) Incentives / Government Support 1. RECODA to offer free support and independent advice as well as incentive programmes such as, pioneer status, discount on industrial land, tax exemption to foreign companies looking to invest or locate in SCORE. (SCORE 2015) Various financial incentives from government such as CTF Investment Plan to support renewable energy (Damuri and Atje 2012) Various benefits such as tax exemption, free rental for investment more than USD 500000, education, healthcare, housing , travel and social welfare for foreign investor(KPMG 2008)
  43. 43. 36 Appendix C: Process Simulation Basis of Design Table C.1. Property method, model and general assumptions for simulation thermodynamics Aspects Descriptions Process type Common Base method SOLIDS - Solids are involved and this package is recommended for coal processing according to the property method selection assistant in Aspen Plus. The simulation of heat and mass balances of a solids process required for the physical property model is suitable for solid components (AspenTech 2000). - Hence, the models that specialized in physical property for solid components are required. For instance,accurate data of solids particle size distribution can be expected for solid equipment such as cyclones. Stream class MIXCINC Free-water method Steam-TA General assumptions - Gasification process is at steady state and isothermal - No heat loss from the reactors throughout the whole process - All reactions reached chemical equilibrium - Specific heat (cP) of species is independent of operating pressure at which reaction takes place. - Specific heat (cP) of species stay constant at the average of the reactor feed temperature and calculated equilibrium (or reactor outlet) temperature. Table C.2. Ultimate analysis (% wt) of coal and rice husk by dry ash free basis Ultimate Analysis C (%) H (%) O (%) N (%) S (%) Reference Coal 78.03 5.06 5.66 1.69 1.97 Boharapi, Kale and Mahadwad (2015)Rice Husk 36.1 1.94 37.8 4.8 - Table C.3. Proximate analysis (% wt) of coal and rice husk Proximate Analysis Moisture (% ) Fixed Component (% ) Volatile Matter (% ) Ash (% ) Reference Coal 9.07 55.44 36.97 7.59 Hoffman (2003) Rice Husk 8.44 9.3 71.4 19.3 Panda (2012) Table C.4. Sulphur analysis (% wt) of coal with 1.97% sulphur in ultimate analysis Sulphur Analysis Pyritic Sulphate Organic Reference Coal 0.91 0.15 0.91 Hoffman (2003)

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