The document discusses pyrolysis, a process where organic substances in solid waste are thermally cracked into gaseous, liquid, and solid fractions when heated in an oxygen-free environment. Pyrolysis is endothermic, consuming heat, unlike combustion which is exothermic. At different temperatures, pyrolysis produces a gas stream containing hydrogen, methane, carbon monoxide and dioxide; a liquid tar/oil fraction; and a solid carbon fraction with inert materials. The document also briefly discusses dumping solid waste by barge in the sea, noting disadvantages like lighter materials floating back to shore.

1. • NAME – KAPTAN SAGAR R
• ENROLLMENT NO. – 130140106021
• SUB. – ENVIRONMENTAL ENGINEERING
• TOPIC – PYROLYSIS

2. Upon heating in close containers in oxygen
free atmosphere, most of the organic substances of
solid waste can be split through combination of
thermal cracking and condensation reactions into
gaseous, liquid and solid fraction, This process is
known as ‘pyrolysis’ or ‘thermal pyrolysis’.

3. In contrast to the combustion process
which is highly exothermic ( releasing heat on
burning in the presence of oxygen ), the
pyrolysis is highly endothermic ( consuming
heat ). That is why, this process is also known
as destructive distillation.

4. The pyrolysis of organic solid waste, produced the
following products at different temperatures.
(1) a gas stream :
The generation of a gas fraction containing primarily hydrogen,
methane, carbon monoxide, carbon dioxide and various other
gases.
(2) a liquid fraction :
The generation of a liquid fraction consisting of a tar/or oil,
steam containing acetic acid, acetone and methanol.
(3) a solid fraction :
The generation of a solid fraction consisting of almost pure
carbon with other inert materials that have entered the
process.

8. Solid waste/refuse can also be disposed of by barging out
into the sea, after carrying it at reasonable distance (say 15 to
20 km) into the sea. The sea depth at such disposal point
should not be less than 30m or so, and the direction of the
currents should be such as not to bring it back towards the
shore.
Radioactive substances are packed in containers and
taken deep into the sea and then dumped. These containers
reach the bottom of the sea. In due course they lose their
radioactivity.

9. This method is quite cheap and simple, but
possesses the following disadvantages :
1. Bulky and lighter matter may float, spread out and tend to
return to the shores during high tides.
2. During stormy weather and monsoons, it is not possible to
send barges out into the sea.
3. Inspite of best care, some portion of refuse may return the
shores and spoil them.
4. The method is suitable only in case of coastal cities.