Pyrolysis is the thermal decomposition of organic material at elevated temperatures in an oxygen-free environment. It involves chemical changes and phase changes to the material. Pyrolysis of biomass produces bio-oil, char, and syngas. It occurs above 430°C without direct contact with oxygen or other reagents. Common pyrolysis types are dry pyrolysis, which occurs at various temperatures to produce different products, and oxidizing pyrolysis, where a small amount of oxidation takes place despite attempts at an oxygen-free environment.

1. PYROLYSIS
Prepared by :
Afizah Abd Aziz
Izza Nadhira Zaidin
Ahmad Asyraf Abd Majid
Mohd Khairul Firdaus
Mohd Naqiuddin Aziz Affendi
AS223 - B.Sc (Hons) Polymer Technology

2. DEFINITION
thermal decomposition
of organic material at
elevated temperatures
in the absence of
oxygen
Involves chemical
change of chemical
composition and
physical phase
IrreversibleEndothermic
AS223 - B.Sc (Hons) Polymer Technology

3. WHAT IS PYROLYSIS?
 Pyrolysis does not involve reactions with
oxygen, water, or any other reagents.
 In practice, it is not possible to achieve a
completely oxygen-free atmosphere.
 Because some oxygen is present in any
pyrolysis system, a small amount of
oxidation occurs.
AS223 - B.Sc (Hons) Polymer Technology

4. WHAT IS PYROLYSIS?
Pyrolysis is :
AS223 - B.Sc (Hons) Polymer Technology

5. WHAT IS PYROLYSIS?
Pyrolysis is :
How?
WHAT IS PYROLYSIS?
AS223 - B.Sc (Hons) Polymer Technology

6. WHAT IS PYROLYSIS?
Pyrolysis is :
WHAT IS PYROLYSIS?
AS223 - B.Sc (Hons) Polymer Technology

7. WHAT IS PYROLYSIS?
Pyrolysis is :
WHAT IS PYROLYSIS?
AS223 - B.Sc (Hons) Polymer Technology

8. WHAT IS PYROLYSIS?
Pyrolysis is :
WHAT IS PYROLYSIS?
AS223 - B.Sc (Hons) Polymer Technology

9. WHAT IS PYROLYSIS?
Pyrolysis is :
WHAT IS PYROLYSIS?
AS223 - B.Sc (Hons) Polymer Technology

10. WHAT IS PYROLYSIS?PRODUCT of PYROLYSIS
Bio Oil
Char
SynGas
AS223 - B.Sc (Hons) Polymer Technology

11. PROCESS
 operating temperatures above 430 °C
(806 °F).
 For agricultural waste, for example, typical
temperatures are 450 to 550 °C (840 to
1,000 °F).
AS223 - B.Sc (Hons) Polymer Technology

12. PRO’S N CON’S
 Cheap and
economical system
 Environment-
friendly,
 Energy-efficient
 Requires drying of soil
 Ineffective in
destroying or
physically separating
inorganics from the
contaminated
medium.
 Requiring proper
treatment, storage,
and disposal for
hazardous wastes.
AS223 - B.Sc (Hons) Polymer Technology

13. TYPES OF PYROLYSIS
• Dry pyrolysis
 Low Temperature Analysis
 MediumTemperature Analysis
 High Temperature Analysis
• Oxidizing pyrolysis
AS223 - B.Sc (Hons) Polymer Technology

14. Dry Pyrolysis
 Process of thermal decomposition without
access of oxygen (O₂)
 Product of dry pyrolysis are gas with high heat
of combustion, liquid and solid carbon residue.
 Type of dry pyrolysis depend on the
temperature of the process.
AS223 - B.Sc (Hons) Polymer Technology

15. AS223 - B.Sc (Hons) Polymer Technology

16. Oxidizing Pyrolysis
 It’s impossible to achieve a completely
oxygen-free atmosphere.
 Thus, a small amount of oxidation occurs.
If volatile or semi-volatile materials are
present in the waste, thermal
desorption will also occur.
AS223 - B.Sc (Hons) Polymer Technology

17. Oxidizing Pyrolysis
 Thermal decomposition of industrial waste by
its partial burning or direct contact with end
product of fuel combustion
 This method is used for neutralization of most
wastes including “inconvenient” ones for
burning
AS223 - B.Sc (Hons) Polymer Technology

18. AS223 - B.Sc (Hons) Polymer Technology