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Plastics Waste as a Resource for Fuel
Plastics have become an integral part
and parcel of our lives due to its economic value, easy availability,
easy processability, light-weight, durability and energy efficiency,
besides
other benefits.
Since plastics are re-usable and
recyclable,
there should not have been any problem of disposal of the plastics
waste, however due to our poor littering habits and inadequate waste
management system/infrastructure, plastics waste management, disposal
continues to be a major problem for the civic authorities, especially in
the urban
areas.
Though various steps have already
been either
taken or initiated by the Government and the legal/civic authorities to
reduce the problem of this waste management, an innovative
invention by Prof. Alka Umesh
Zadgaonkar of the Department of Applied Chemistry, G.H. Raisoni College
of Engineering, Nagpur, Maharashtra, has created a hope and scope to
tackle this problem more easily and more environmentally-friendly manner.
She has invented a catalyst system, which converts polymeric materials
into liquid, solid and gaseous fuels.
The Process
Under
controlled
reaction
conditions, plastics
materials undergo random de-polymerization and is converted into three
products:
a) Solid Fuel – Coke
b)
Liquid Fuel
– Combination of Gasoline, Kerosene,
Diesel and Lube Oil
c)
Gaseous Fuel
– LPG range gas
The process consists of two steps:
i) Random de-polymerization
-
Loading of waste plastics into the reactor along with the Catalyst
system.
-
Random de-polymerization of the waste plastics.
ii) Fractional Distillation
-
Separation of various liquid fuels by virtue of the difference in their
boiling points.
One important factor of the quality
of the liquid
fuel is that the sulphur content is less than 0.002 ppm
– which is much lower than the
level found in regular fuel.
Principles Involved
All plastics are polymers mostly
containing
carbon and hydrogen and few other elements like chlorine, nitrogen, etc.
Polymers are made up of small molecules, called monomers, which combine
together and form large
molecules, called polymers.
When this long chain of polymers break at certain points, or when lower
molecular weight fractions are formed, this is termed as degradation of
polymers. This is reverse of polymerization or
de-polymerization.
If such breaking of long polymeric
chain or
scission of bonds occur randomly, it is called ‘Random depolymerization’.
Here the polymer
degrades to lower molecular fragments.
In the process of conversion of
waste plastics
into fuels, random depolymerization is carried out in a specially
designed reactor in the absence of oxygen and in the presence of coal
and certain catalytic additives. The maximum reaction temperature is 350oC.
There is total conversion of waste plastics into value-added fuel products.
Unique features of the process and product obtained are:
-
All types of Plastics Waste including CD’s and Floppies having metal
inserts, laminated plastics – can be used in the process without any
cleaning operation. Inputs should be dry.
-
Bio-medical plastics waste can be used.
-
About 1 litre of Fuel is produced
from 1 kg of
Plastics Waste. Bye-products are Coke and LPG
Gaseous Fuel.
-
Any possible dioxin formation is
ruled out during
the reaction
involving PPVC waste,
due to the fact that the reaction is carried out in absence of oxygen, a
prime requirement for dioxin formation.
-
This is a unique process in which 100%
waste is converted into 100% value-added products.
-
The process does not create any pollution.
Though the fuel so produced from
the plastics
waste could be used for running a four-stroke/100 cc motorcycle at a
higher mileage rate, the inventor agrees that separation of petrol from
the
liquid fuel could be a complex
generation. Nevertheless the product is good enough for use as an
alternative clean fuel in boilers and other heating systems.
It is, however, not the first time that
fuel has been
produced out of plastics waste. A Japanese company, M/s. Ozmotec, is
already manufacturing fuel out of plastics waste at an industrial plant
in Japan employing the Pyrolysis process. However, Prof. Zadgaonkar’s
process is a continuous one and hence is cheaper, whereas the Japanese
technology is a batch process and is
comparatively costlier.
A
live demonstration of the
production of
Liquid Fuel was made in the presence of ICPE led team in the laboratory.
Three kgs of plastics scrap was used to produce about 2 litres of Liquid
Fuel in about 3 hrs. The reaction was terminated after the trial demo.
The fuel obtained was used in smooth running of a motorcycle, which was
experienced by the visiting members. However, the inventor does not wish
to claim the product as a substitute for Petrol or Diesel at this stage.
The present use would be as a fuel for running
boilers and other heating purposes.
A
report from the Team comprising Mr. T.K.
Bandopadhyay of ICPE and Dr. Shashikant Sharma of IPCL’s R&D Department,
who were deputed by ICPE management to visit Nagpur.
Text of the report is based on the information provided by the inventor
(Source:
Eco Echoes, Mumbai) |
