2. Submitted By – Rupal Jain
Ph.D First Yr (REE)
Under guidance – Dr. S.K. Jain
Professor (PFE)
3. Contents
Introduction
Characterization of Vegetable Wastes
Treatment Methods
Identification of different compound
Anaerobic digestion of vegetable waste
Comparison of waste treatment method
4. Introduction
Vegetable waste is a biodegradable material generated
in large quantities from various sources like, domestic,
industries, municipalities and markets.
Vegetable wastes include the rotten, peels, shells, and
scraped portions of vegetables or slurries.
These wastes generated at different levels of delivery
starting from the agricultural farm, post-harvest handling,
storage, processing, and from distribution to consumption
of human beings.
It has been observed that of the enormous supply of food
for human consumption, about one-third gets wasted
globally.
5. Characterization of Vegetable Wastes
Physical characteristics of solid wastes includes estimation of weight, volume,
moisture, ash, total solid, volatile solid (VS), color, odor, temperature, etc.
Chemical studies include the measurement of cellulose, hemicellulose, starch,
reducing sugars, protein, total organic carbon, phosphorus, nitrogen, BOD, COD,
pH, halogens, toxic metals, etc. Besides these biochemical parameters, carbon,
phosphorous, potassium, sulfur, calcium, magnesium, etc. can also be tested.
Biologic characteristics indicates the presence of pathogens and organisms which
are indicators of pollution. A common feature of various forms of food wastes
includes high COD, richness in protein, carbohydrate, and lipid bio-molecules with
noticeable pH variation.
6. Waste Moisture
(per cent)
Ash
(per cent)
Total solid (per
cent)
Potato (leachate/solid waste) 85-87 6-12 1.7-19
Tomato (solid waste) 85-90 3.1-5.3 7-22.4
Onion (onion tops peelings and whole
bulbs)
82–92.6 4.7 ± 0.1 91 ± 0.25
Pea (peel, shell, and solid waste) 84–88.5 4.80–15.5 11.11–39
Sugar beet (pulp, silage, and leaves) 85 ± 0.1 3.81–8.85 7–11
Table 1: Physical characteristics of different types of vegetable wastes (dry basis)
Waste Starch
(per cent)
Cellulose
(per cent)
Hemicellulose
(per cent)
Protein (per
cent)
Potato (Peel, mesh) 30-40 17-25 10-15 3-5
Tomato 10-18 30-32 5-18 17-22
Carrot 1-2 13-52 12-19 5-8
Table 2: Chemical characteristics of different types of vegetable wastes
7. Fig.1 Vegetable waste utilization methods
Treatment Methods
1. Store the culled fruit and vegetables on-site in a pile or bermed area for a limited
time
2. Return fruit and vegetable waste to the field on which it was grown
3. Feed fruit and vegetable waste to livestock
4. Give the fruit and vegetable culls to local food banks
5. Compost fruit and vegetable culls
6. Process fruit and vegetable culls to separate juice from pulp
7. Dispose of fruit and vegetable waste in local Sub-Title D landfill
8. Fluidized Bed Combustion
Fluidized bed combustion has been shown to be a versatile technology capable of burning
practically any waste combination with low emissions.
The significant advantages of fluidized bed combustors over conventional combustors include
their compact furnace, simple design, effective burning of a wide variety of fuels, relatively
uniform temperature, and the ability to reduce the emission of nitrogen oxide and sulphur
dioxide gases.
The conversion of existing-fluidized bed combustion boilers to co-firing wastes with coal is
in many cases more cost-effective and efficient.
The combustion of three high moisture content waste materials like olive oil waste, municipal
solid waste, and potato in a fluidized bed combustor and co-firing with coal resulted in
markedly higher combustion efficiencies with an increase of approximately 10–80 per cent.
The co-firing of waste from olive oil production with coal in a fluidized bed combustor found
carbon combustion efficiency of 10 and 20 per cent.
10. Biodiesel
Biodiesel comprises alkyl esters of high fatty acids and low aliphatic alcohols.
Biomass with high lipid content is most suitable for biodiesel production.
The oil rich wastes of vegetable origin like fresh or waste vegetable oils, animal fats, and
oilseed plants fall under this category.
Fatty acid composition of the triglycerides present in the feedstock determines its usefulness
as the calorific value depends on it. Un-saturated fatty acid lowers the energy content,
whereas saturated increases the calorific value.
Alcohol esters of vegetable oils possess characteristics that are very close to that of diesel
fuel.
Rapeseed and sunflower oil in Europe, soybean oil in USA, and palm oil in tropical countries
have been used.
Since edible oil is expensive, search for cheaper oil substrates has been a major focus in
biodiesel research.
11. Fig. Pyrolysis unit for biodiesel production
Biodiesel production using high temperature pre-treated kitchen garbage, waste
(bleaching earth) generated during the crude vegetable oil refining process also reported.
Biodiesel production is also achieved by trans-esterification of vegetable oils with
simple alcohols either using a catalyst or without it.
Reaction temperature, alcohol to oil ratio, mixing speed and purity of reactants are the
other parameters which influence biodiesel production.
12. Composting
Composting is the natural process of 'rotting' or decomposition of organic matter by
microorganisms under controlled conditions.
Compost is a key ingredient in organic farming.
Compost is organic matter that has been decomposed and recycled as a fertilizer and soil
amendment.
Vegetable wastes are purely organic and organic waste can cause problems of smell, leachate,
gas, and stray animals in landfills.
The recycling of waste at source is most economic and environment friendly method of waste
management for which simple composting methods is available and composting at source
keeps inorganic waste clean and makes it easier for recycling.
The compost is valuable resource for farmers.
14. Identification of different compound
Rabaneda et al. 2003 used a new, fast and efficient method combining liquid
chromatography coupled to ion spray mass spectrometry in tandem mode with negative ion
detection is described for the qualitative analysis of artichoke waste.
Forty five phenolic compounds were identified on the basis of their mass spectra in full
scan mode, mass spectra in different MS–MS modes, and retention times compared with
those of available reference substances.
The major compounds were found to be both caffeoylquinic and dicaffeoylquinic acids,
luteolin glucuronide, luteolin galactoside, quercetin, and some quercetin glycosides.
Liquid chromatography coupled to MS–MS proved to be a powerful tool to selectively
screen artichoke by-product extracts for the occurrence of phenolics and structurally related
substances.
15. This would allow a better knowledge of both its chemical composition and its potential
use as a source of natural antioxidants.
Artichoke (Cynara scolimus) is popular for its pleasant bitter taste which is attributed to
phytochemicals occurring in the green parts of the plants.
The presence of phytochemicals in artichoke has been well-documented, the leaves being
higher in medicinal value than flowers, with antihepatotoxic, choleretic, diuretic,
hypocholesterolemic, and antilipidemic properties that are attributed to the phenolic
composition.
Spain is one of the major producers of artichoke in Europe, and the canning industry is
the most important consumer of this crop.
The residues proceeding from this industry can form up to 60 per cent of the harvested
plant material, the final management of these wastes representing an additional problem.
Until the present, the common disposal of artichoke raw material is as organic mass,
animal feed, and fuel and fiber production.
16. The production of biogas from organic material under anaerobic condition involves
sequence of microbial reactions. During the process complex organic molecule present in
the biomass are broken down to sugar, alcohols, pesticides and amino acids by acid
producing bacteria. The resultant products are then used to produce methane by another
category of bacteria. The biogas production process involves three stages namely:
Hydrolysis
Acid formation
Methane formation
Anaerobic digestion of vegetable waste
Portable Biogas Plant for Kitchin Waste
17.
18. CH3COOH CH4 + CO2
Acetic acid Methane Carbon dioxide
2 CH3CH2OH + CO2 CH4 + 2 CH3COOH
Ethanol Carbon dioxide Methane Acetic acid
CO2 + 4 H2 CH4 + 2 H2O
Carbon dioxide Hydrogen Methane Water
19. Comparison of waste treatment method
The comparative presentation of the various vegetable waste treatment methodologies
showed that though bioremediation stands for the most environmentally friendly
technique.
Its required longer treatment time in conjunction with its weakness to deal with
elemental contaminants makes imperative the employment of a second alternative
technique which could either be a membrane process (low energy cost, reliability,
reduced capital cost) or a coagulation/flocculation method because of its low cost and
high effectiveness.
Biogas production appears to be another promising and energy effective waste treatment
method.
On the other hand, methods like distillation and ozonation (high cost) and electrolysis
(experimental level) are unlikely to dominate this field unless their high cost is reduced.