1. Suhas Dixit,
Pyrocrat Systems LLP,
Navi Mumbai
Waste to Energy

2. Definition
 Waste-to-energy is the process of generating energy in the form
of electricity or heat from the primary treatment of waste.
 WtE is a form of energy recovery.
 MostWtE processes produce electricity and/or heat directly through
combustion, or produce a combustible fuel commodity, such
as methane, methanol, ethanol or synthetic fuels

3. Incineration
 Incineration is the process of combustion of waste for energy recovery.
 Modern incinerators reduce the volume of the original waste by 95-96 percent,
depending upon composition and degree of recovery of materials such as metals
from the ash for recycling.
 Incinerators have electric efficiencies of 14-28%.

4. Gasification
 Gasification is a process that converts organic or fossil
fuel based carbonaceous materials into carbon monoxide, hydrogen and carbon
dioxide.
 The material is reacted at high temperatures (>700 °C), without combustion,
with a controlled amount of oxygen and/or steam.

5. Thermal Depolymerization
 Thermal depolymerization (TDP) is a depolymerization process
using hydrous pyrolysis for the reduction of complex organic
materials (usually waste products of various sorts, often biomass and plastic)
into light crude oil.
 Under pressure and heat, long chain polymers of hydrogen, oxygen,
and carbon decompose into short-chain petroleum hydrocarbons with a
maximum length of around 18 carbons.

6. Pyrolysis
 Pyrolysis is the process of thermochemical decomposition of organic material at
elevated temperatures in the absence of oxygen
 The process is used to convert plastic and tire waste into fuel.

7. Plasma Gasification
 Plasma gasification is an extreme thermal process using plasma which
converts organic matter into a syngas (synthesis gas) which is primarily made up
of hydrogen and carbon monoxide.
 A plasma torch powered by an electric arc, is used to ionize gas
and catalyze organic matter into syngas with slag remaining as a byproduct.
 It is used commercially as a form of waste treatment and can be highly useful in
treating hazardous waste.

8. Anaerobic digestion
 Anaerobic digestion is a collection of processes by
which microorganisms break down biodegradable material in the absence
of oxygen.The process is used for industrial or domestic purposes to manage
waste or to produce fuels.
 Anaerobic digestion is particularly suited to organic material, and is commonly
used for industrial effluent, wastewater and sewage sludge treatment.

9. Fermentation
 Fermentation is the primary means of producing energy by the degradation of
organic nutrients anaerobically.
 Hydrogen production by fermentative bacteria is technically simpler than by
photosynthetic bacteria.Also, the fermentation process generates hydrogen
from carbohydrates obtained as refuse or waste products.

10. Mechanical Biological Treatment
 A mechanical biological treatment (MBT) system is a type of waste
processing facility that combines a sorting facility with a form of biological
treatment such as composting or anaerobic digestion. MBT plants are designed
to process mixed household waste as well as commercial and industrial wastes.
 The‘mechanical’ element is usually an automated mechanical sorting stage.This
either removes recyclable elements from a mixed waste stream (such as metals,
plastics, glass and paper) or processes them.

11. THANK YOU