Plastic bags as building blocks

World over, civic bodies are grappling with the problem of solid
waste, especially safe disposal of large amounts of plastic waste.
None of the local bodies in Kerala has found a green solution for
plastic waste management in spite of the State government banning the
manufacture, sale and use of plastic carry bags of thickness below 30
microns. Now, the Koyilandy municipality in Kozhikode district is
getting ready to launch a project making use of plastic carry bags to
manufacture plastic bricks for construction of houses. The Science and
Technology Entrepreneurship Development (STED) Project, under the
Department of Science and Technology of the State government, is
providing the technical know-how to the municipality. Already a few
rounds of discussion have been held between STED officials and the
elected representatives of the municipality. The experimental project
will be the first of its kind in the State, says Mohanan Manalil,
project director, STED. The technique is simply to repurpose this
environmentally unfriendly material. Usually, non-biodegradable
plastic is segregated and sold to plastic recycling companies.
However, plastic carry bags accumulate in backyards and junk bins. It
will be these non-recyclable bags that will go into the making of the
bricks, he says. In fact, the use of non-recyclable plastic such as
carry bags is high in the State as in any other part of the globe.
Plastic carry bags, it has been proved, can take nearly 1,500 years to
decompose. The overuse of plastic has caused severe havoc to the
planet. Elucidating the project details, Mr. Manalil says that
non-recyclable plastic waste with thickness ranging from 20 microns to
100 microns will be collected and ground into 10-mm granules. These
granules will then be melted at a temperature of 150 degrees Celsius.
And finally, the liquefied plastic will be thoroughly mixed with baby
metal, giving it a concrete form.
Just as soap is manufactured, cut and packed into fine shape, the new
product is cut into a standardised mould. Thus, the plastic brick is
ready. The simple project has often been displayed at school
exhibitions at the micro level. Today, it is reaching the commercial
stage, he says. The plastic brick requires no cement, no sand and no
plastering. No painting is required for exterior walls and even for
interiors of the house if the occupant is particular of avoiding
frills. Colours can be used according to the taste of the individual,
he adds. Machinery for the brick-manufacturing unit has to be
tailor-made. There are such machine-manufacturing units in Ernakulam
and Thrissur. Talks have been held in this regard with a
Thrissur-based company. Plastic bricks are cost-effective when
compared to cement, hollow, wire-cut and ordinary bricks made at
brick-kilns. Initially, the municipality will have to invest between
Rs.15 lakh and Rs.20 lakh for the project for setting up the
centralised machine unit. The civic body will seek the support of
private entrepreneurs in the successful implementation of the
project.Already, STED has successfully implemented a project with
joint partnership of NATPAC using plastic waste in lieu of bitumen in
construction of roads. More than 10 per cent of the bitumen usually
required has been saved in case of construction of such roads in
Kozhikode city. Apart from developing a technology for safe disposal
of plastic, the project will also generate employment in the region.
Kudumbasree volunteers will be engaged in the segregation of plastic
waste and their services will again be used in the manufacture of
plastic bricks. Besides, the municipality will happily get rid of its
solid-waste problem, says Mr. Manalil.
Recovery unit
All the 41 wards in the municipality will have a source recovery unit
to collect solid waste. The biodegradable waste will be converted into
manure while other waste such as paper will be sent to recycling
units. The plastic waste will be graded, some will be converted into
pellets, which have a market value of Rs.45 a kg, and other into
granules which will be sold at Rs.30 a kg. The non-recyclable plastic
waste, which has no takers, will be used for manufacturing the plastic
bricks, he says. Mr. Manalil says that the civic body has resources
and manpower, thus giving a positive side to the implementation of the
project. It only needs feasible schemes and know-how to fruitfully
implement them. Plastic carry bags can be handy and highly useable in
our daily lives. But their safe disposal has put us in a quandary. Now
a municipality in collaboration with a government agency has come up
with an alternative solution.
The Hindu, July 4