Increasing sludge production and stringent sludge disposal norms have forced many municipal organisations and sludge disposal companies to look for alternatives for sludge disposal and solutions to recover nutrients. The Sludge2Energy system safely treats and disposes sludge and recovers useful nutrients with zero net energy addition. Click on the link below to learn more.

1. Sludge2Energy
Energy self-sustaining sewage sludge
utilisation process
A.T.E. HUBER Envirotech Private Limited
www.atehuber.com
v4.0 Dec 2020

2. About Sludge2Energy
The Sludge2Energy system safely treats
and disposes sludge and recovers useful
nutrients with zero net energy addition.

3. About Sludge2Energy
▪ Increasing sludge production and stringent sludge disposal norms have forced many municipal organisations
and sludge disposal companies to look for alternatives for sludge disposal and solutions to recover nutrients
▪ Rising disposal and transportation costs, the need for economic use of resources, and the recovery of
phosphorus from sewage sludge ash, has led many to turn to thermal sewage sludge utilisation
▪ HUBER and WTE have developed an innovative ‘sludge2energy’ process to utilise sewage sludge. This energy
self-sufficient method is based on a combination of a medium-temperature belt dryer with subsequent
combustion in a fluidised bed furnace
▪ Sludge2energy process enables sustainable waste management by thermally consuming sewage sludge (at
the wastewater treatment plant) by incineration. Co-generated heat is used for dryer operation
▪ Sludge mass is reduced by drying and incineration to about 10%. The remaining ash can be deposited at a
separate site. It is possible to recover the phosphorus from the ash through an additional process

4. ▪ Efficiently combines drying and thermal utilisation of
sewage sludge in a fluidised bed furnace
▪ A wide variety of municipal sewage sludges can be
utilised thermally, and due to an efficient use of
energy, without the need for any external energy.
▪ Compact, modular and functional design with
minimum space requirements
▪ Low investment and operational costs due to the
optimised thermal drying and utilisation
▪ Optimal sewage sludge quantity and mass reduction
▪ Minimised expenses and costs for sewage sludge
transport
▪ Long-term cost certainty and disposal safety
Benefits of the Sludge2Energy process
▪ Dry flue gas cleaning process without generation of
wastewater
▪ Fully automatic operation 24×7, with a high plant
availability of 8,000 hours/year
▪ High flexibility of sewage sludge utilisation
▪ Production of phosphorus-rich sewage sludge ash
and optional phosphorus recovery
▪ Optimised flue gas cleaning depending on customer
requirements (site requirements, phosphorus
recovery)
▪ Optional power generation depending on specific
individual conditions and plant size

5. Sludge2Energy – features and versions
▪ Plant is tailor-made to the customer’s sewage sludge volumes and requirements
▪ Individual components can be varied to suit customer-specific requirements
▪ Maximum performance and economic efficiency is achieved by selecting the best
suitable technical solution
▪ Depending on the specific site conditions, two design versions are available:
▪ Hot water boiler
▪ Steam boiler

6. Sludge2Energy process flow diagram – hot water boiler variant

7. ▪ Sludge acceptance and storage area for dewatered sewage sludge
(1) to balance varying supply volumes
▪ Full drying of a partial flow in a belt dryer (2) and heat supply
through incineration
▪ Condensation of dryer vapour, introduction of vapour/air into
fluidised bed furnace (6) as combustion air
▪ Intermediate storage bunker (3) for dried sewage sludge
▪ Mixing (4) of dewatered and fully dried sludge for auto-thermal
incineration
▪ Flexible combustion control including adjustable conveying line for
combined sludge input
▪ Stationary fluidised bed furnace (5) with continuous discharge of
bed material and contaminants
▪ Burner for plant start-up and shutdown and balancing unsteady
operating states
▪ Waste heat boiler (6) for heat transmission from flue gas to useable
hot water
▪ Utilisation of the hot water for heat supply to internal consumers,
such as sludge dryer
Sludge2Energy process – hot water boiler variant

8. ▪ Staged combustion air system to minimise contaminants, such as
dioxins, carbon monoxide, organic pollutants and nitric oxides
▪ Denitrification according to the selective non-catalytic reduction
(SNCR) method as first stage of flue gas cleaning
▪ Fabric filter for pre-separation (7) of the phosphorus-rich flue ash
from the flue gas
▪ Dry flue gas cleaning (8) with sorbent dosing to remove acid
pollutants, dioxins and heavy metals (for e.g., Hg)
▪ Fabric filter (9) (sorption filter) to remove reaction products and
dust from the flue gas
▪ Recirculation of the sorption residues to improve separation
efficiency and reduce sorbent consumption
▪ Measurement station in chimney (12) for the control of all legal
emission limits
▪ Ash discharge and storage of reaction products (11) separately
from phosphorus-rich bed ash, boiler ash and pre-separated ash
(10)
Sludge2Energy process – hot water boiler variant (contd.)

9. Sludge2Energy process flow diagram – steam boiler variant

10. Sludge2Energy process – steam boiler variant
▪ Sludge acceptance and storage area for dewatered sewage
sludge (1) to balance varying supply volumes
▪ Partial drying in a contact dryer (2) for auto-thermal incineration
of the sludge
▪ Flexible combustion control including adjustable conveying line
for controlled sludge input (3)
▪ Condensation of dryer vapour, introduction of vapour/air into the
fluidised bed furnace (4) as combustion air
▪ Stationary fluidised bed furnace (4) with continuous discharge of
bed material and contaminants
▪ Burner for plant start-up and shutdown and balancing unsteady
operating states
▪ Waste heat boiler (5) for heat transmission from flue gas to
useable vapour
▪ Energetic utilisation of the vapour via a counter-pressure steam
turbine (12) with generator
▪ Utilisation of the exhaust steam for heat supply to internal
consumers, such as sludge dryer

11. Sludge2Energy process – steam boiler variant
▪ Staged combustion air system to minimize contaminants, such as
dioxins, carbon monoxide, organic pollutants and nitric oxides
▪ Denitrification according to the selective non-catalytic reduction
(SNCR) method as first stage of flue gas cleaning
▪ Fabric filter for pre-separation (6) of the phosphorus-rich flue ash
from the flue gas
▪ Dry flue gas cleaning (7) with sorbent dosing to remove acid
pollutants, dioxins and heavy metals (for e.g., Hg)
▪ Fabric filter (8) (sorption filter) to remove reaction products and
dust from the flue gas
▪ Recirculation of the sorption residues to improve separation
efficiency and reduce sorbent consumption
▪ Emission measurement station in chimney (11) for the control of all
legal emission limits
▪ Ash discharge and storage of reaction products (10) separately
from phosphorus-rich bed ash, boiler ash and pre-separated ash
(9)

12. Sludge2Energy – references
Thermal waste utilisation plant, Dumrohr, Austria Thermal waste utilisation plant, Moscow, Russia Sewage sludge utilisation plant, Bello, Colombia
Sludge incineration plant under execution at Halle-Lochau,
Germany
Waste incineration plant, Kuwait Huber Belt Dryer, Nova Gorica, Slovenia

13. About us
HUBER SE
HUBER SE, headquartered in Berching, Germany, is a global company active
in the fields of water, wastewater and sludge treatment.
More than 1000 employees worldwide develop and manufacture products,
manage projects and develop system solutions for municipalities and
industries.
With more than 45,000 installations worldwide HUBER is one of the
internationally leading companies in this field. HUBER's adapted treatment
processes contribute to the solution of the global water problems.
WTE EVN Group
WTE Group provides designing, construction, financing and operation of
engineering plants for wastewater disposal, water supply, energy production
and thermal waste utilisation.
WTE with their expertise develop future-proof solutions which set the
international standards in terms of energy efficiency, consumption of resources
and investment costs.
WTE utilise all energy sources in the process chain to ensure the energy self-
sufficient operation and environmental sustainability of the plants.
Sludge 2 Energy GmbH
Sludge 2 Energy GmbH offers comprehensive expertise of HUBER SE and WTE GmbH in planning, building and operating plants in the fields of wastewater and sludge
treatment, thermal waste utilisation, and especially the know-how and knowledge of process-technical, energetic and logistic synergies in the field of sewage sludge treatment
and develop a cost-effective and reliable modular system that meets specific customer requirements.
A.T.E. Huber Envirotech Private Limited
A.T.E. HUBER Envirotech Private Limited (AHET) is a joint venture between A.T.E., India, and HUBER SE, Germany. AHET Provides comprehensive solutions for
wastewater treatment, recycling and sludge management for industry and municipal sector. AHET has developed innovative technologies for industrial waste water treatment,
recycle and zero liquid discharge

14. THANK YOU