Page 20 - Plastcs News January 2019

FeAtures

Award-level solution to Plastic waste

A team of students from IIT-Madras has developed a solar-powered mobile unit that converts non-recyclable
plastic waste into fuel oil that is cheaper than diesel

owadays, pyrolysis is getting attention for its plastic waste is fed into the pyrolysis unit to the time it
Nflexibility to generate a combination of solid, liquid is converted into oil.The unit can currently process only
and gaseous products in different proportions just by the 5 kg of plastic at a time. The unit uses as much as 3-4
variation of operating parameters such as temperature units of power/kg/hour.
or heating rate. It also provides an opportunity of “Large-scale pyrolysis units have been unsuccessful due
transforming materials of low-energy density into bio- to issues like transporting plastic waste. We designed
fuels of high-energy density.
a mobile, transportable unit that can be installed in
Students of Indian Institute of Technology-Madras have sorting centres at the ward or zonal garbage segregation
come up with a solution to tackle non-recyclable plastic centres,” said G. Divya Priya, a post-doctoral research
waste. A team of students from IIT-Madras has developed scholar involved in the project.
a solar-powered mobile unit that converts non-recyclable The residue (sludge) generated during the burning
plastic waste into fuel oil that is cheaper than diesel
process is compressed and made into light charcoal
The five-member Team Enviro, which included a student briquettes, which can also be reused to run the unit.
from SSN College of Engineering, has developed a mobile The briquettes can also be used to power medium and
solar-powered pyrolysis unit to convert plastic into oil.
A kilogram of plastic can produce 500 to 700 ml of oil,
depending on the quality of plastic used, the team said.
The technology, when scaled up into a full-fledged
commercial product, can be the ideal solution for
city corporations to manage plastic waste. This green
technology — Plastic Pyrolysis — essentially breaks down
polymer chain in plastic at 350-500 degree Celsius in the
absence of oxygen to get the low density fuel oil.

The best thing about this technology is that even
waste such as plastic bags, packaging material and small-scale industrial units, said team mentor Indumathi
other miscellaneous plastic stuff that are not normally M. Nambi, professor, Environmental and Water Resources
picked up by ragpickers for recycling can be used as Engineering Division.
raw materials. These non-recyclable varieties are a real
nightmare as they do not degrade, but clog drains, choke Wide appreciation
livestock and mar the environment. The unit was demonstrated at the UN World Environment
Day exhibition in New Delhi earlier this year. It has
To conduct experiments, the team procured plastic waste
from the Chennai Corporation garbage sorting centre in also won the team the innovation excellence award
Velachery. “If we use virgin plastic of good quality, we and funding to incubate a start-up at the institute’s
can get as much as 800 ml of fuel. But the plastic we get research park. Already NGOs and some community-level
from the sorting centre is often soiled and so the quantity organisations have approached the team. Chennai and
of oil is less,” said K. Sivagami, a team member. Thoothukudi corporations have also expressed interest in
the product. “We have submitted a proposal for building
Quick conversion a pilot-scale plant for a municipality or corporation with
This fuel oil can be used in generators, motor boats and a daily generation capacity of 250kg of non-recyclable
irrigation pumpsets. It takes 90 minutes from the time plastic waste,” Ms. Sivagami said.

Plastics News Januar y 2019 20