The Hindu                 03.05.2013

A technology that makes the most of the plastic waste

S. Annamalai

The technology is used for laying “all-weather roads”

From October 4, 2002, when the first ‘plastic road’ was laid on Lenin Street, Kovilpatti in Tuticorin district, the technology of using waste plastic with stone for laying roads has come a long way.

Developed by the Department of Chemistry of Thiagarajar College of Engineering, Madurai, in 2001 and patented in 2002, the technology has been literally going places. It is now used in several other States, including Kerala, West Bengal and Himachal Pradesh, to lay “all-weather” roads.

It has also come as an answer to municipal solid waste management. Plastic is common man’s friend and its disposal is a human problem, says R. Vasudevan, who led the research into use of waste plastic for road laying.

According to him, used plastic comprises 2.8 per cent of municipal solid waste in Chennai, compared to 1.46 per cent of Delhi, 1.54 per cent of Kolkata and 0.9 per cent of Bangalore. Disposal of waste plastic either by burning or land filling is hazardous to the environment. The plastic road process involves shredding of waste plastic to small pieces (1.6 to 2.5 mm) and mixing with aggregate at a temperature of 170 degree C. Molten plastic waste laminates the stone in 30 seconds and plastic coated aggregate is added to bitumen for laying roads. The strength of the road gets doubled when plastic is used, says Dr. Vasudevan.

It can withstand heavy load and traffic and is not affected by water stagnation. Its minimum life is seven years, with zero maintenance. Performance studies carried out on plastic roads in Tamil Nadu, under Central Road Research Institute specifications, have shown “good results.” It is an in situ process and can be easily adopted, without use of additional machinery. There is no investment but only saving. Waste plastic found along road flanks in any area is enough for value addition, he says.

The Hindu                 02.05.2013

Salem Corporation resumes garbage dumping at compost yard

In spite of stiff opposition from local residents, City Municipal Corporation has once again resorted to dumping of garbage in Erumapalayam compost yard and in parts of Suramangalam due to erratic power supply at the Solid Waste Treatment Plant at Chettichavadi, on the outskirts of the city.

Though the plant, operated by a private company, has a capacity to process 300 MT solid waste everyday, they receive only 100 tonnes of garbage from the civic body as the plant could be operated for only about five to seven hours a day due to erratic power supply.

The rest of about 200 tonne garbage was dumped in the compost yard and set on fire, causing air pollution.

Residents in Kitchipalayam and nearby areas complain that thick black smoke emanating from the yard is causing health issues and children and elderly people are getting affected.

“Our protest against dumping yields no results as tractors carrying garbage keep pouring through out the day,” said a resident in the area.

Around three lakh metric tonnes of solid waste was dumped in the 14-acre yard at Erumapalayam for over 50 years, resulting in the mounting garbage rising to a height of about 20 feet.

However, Corporation officials said that they had no other option to dispose of the garbage collected every day from 60 wards, as the plant could not be fully operational.

“We have suggested to the company to produce power from their products’ output,” said Commissioner M. Ashokan.

Recently, residents in a few areas in the region also blocked the tractors carrying garbage, to protest against the dumping. But over 50 vehicles continue to dump the garbage at the yard.

Mayor S. Soundappan told The Hindu that electricity board had already been requested to provide uninterrupted supply to the plant so that it becomes fully operational.

“The situation may continue for another two months and until then dumping in yards would continue,” he added.