Date:04/03/2011 URL: http://www.thehindu.com/thehindu/mp/2011/03/04/stories/2011030452000800.htm
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Solution to plastic pollution

SOMA BASU

Concerned about a world strangled by plastic, Dr. R. Vasudevan, tells SOMA BASU how he adds value to the waste by using it in laying all -weather roads

Photos : G. Moorthy

INDEFATIGABLER.Vasudevan, Dean and Head, Department of Chemistry, TCE

The gravel is heated at 170 degrees C and shredded plastic sprayed over the hot stone aggregate. The plastic instantly melts and coats the gravel without releasing toxic gases into the atmosphere. Immediately, bitumen heated at 160 degree C is mixed at 155 degrees C and used for laying the road. Molten plastic with liquid tar has proven to be more resistant to water permeation, heat and high pressure than the normal mixture of stone aggregate and bitumen, without the plastic.

A fter the city's rain-fed potholes, the transition to smooth roads within the campus of the Thiagarajar College of Engineering (TCE) is more than a treat. The man behind the tar-topped tracks, is known as Madurai's ‘Plastic Road Man'.

Always sporting a striking namam on his forehead, he is as much at ease when he experiments with chemicals in the science lab, holding beakers over flames as under a peepul tree when he talks with a bunch of students at lunch break, teaching them shlokas from the Bhagavad Gita.

He could easily be mistaken for a Sanskrit pundit if you heard him quote the holy text as a solution to any problem in the world. Mesmerized students remain tuned in to his discourse. Ever since he joined TCE in 1975, he has carried the Gita as a manual for leading life and voluntarily conducted classes uninterrupted for 36 years.

But Dr. R. Vasudevan, Dean and Head of the Chemistry Department, is better known as a man with a mission, and . “Clean India” is his campaign. The low -profile professor says, “I want to change the general garbage culture of the people.”

After a decade's hard work and persistent efforts, his simple invention of a technology to use -- plastic waste to lay roads, patented by TCE, finally got a shot in the arm last month with the Centre approving its wider application.

The day we met Dr. Vasudevan, the skies burst open. Yet, students assembled in his office room for the ‘Gita class'. And it turned out to be a lucky hour. The professor, at his table cluttered with samples of bitumen blocks, was waving a special gazette notification of the Ministry of Environment & Forests dated 4th February, 2011, directing all municipal authorities across the country to “encourage use of plastic waste by adopting suitable technology such as in road construction...”

Dr. Vasudevan was elated. “This is the first response of its kind to waste management.,”

It was in 2002 that Dr. Vasudevan laid the first plastic tar road within the TCE campus. It remains intact. His interest in the subject began when he heard a doctor on a TV programme mistakenly sayingthat plastic “dissolved” in water bodies and caused pollution. “It set me thinking … after all, plastic's raw material is petroleum only. I immediately came to my lab and started mixing some waste plastic in heated bitumen (tar).” And there and then was born a new idea.

When then President Dr. A.P.J. Kalam visited TCE in 2001, the professor presented his project on the good bonding and binding factor of plastic and its potential use as a coating over pebbles for laying roads. He recalls with a gentle smile, “he told me, one day your test will become the convention. Don't worry if people don't approve or get convinced. You just do your work at your place. As a sample, lay a plastic road within your campus first. Once the results are there to see, people will come automatically.”

Dr. Kalam's words proved prophetic. With full support from the college correspondent Mr. Karumuttu T. Kannan, Dr. Vasudevan laid the first 60-foot -long plastic road within the campus. “Application of knowledge is very important,” he says. “We learn and know so many things but on most occasions fail to see how and where our knowledge could be implemented. That is wisdom.”

Getting his technology patented was the next hurdle. After four years and numerous visits to the Chennai office, the technology was registered in 2006. “An officer advised me that I should not apply for the product's patent because it is not new, the road is already there. Instead, I should patent the process,” he says. “God has always sent the right people to me at the right time.”

Though plastic waste has been a nagging problem for civic authorities, with thousands of tonnes of garbage generated every day, it took years of discussion for Dr. Vasudevan to be acknowledged by organizations like the Central Pollution Control Board, National Rural Roads Development Agency, Central Road Research Institute, Indian Centre for Plastic Environment and the National Highways Authority of India. In every forum, he painstakingly explained and demonstrated the benefits of road laying using a polymer-aggregate-bitumen mix.

Even as his technology was being debated in the government, Dr. Vasudevan started receiving offers from private companies both within and outside the country to sell the patent. “But I think it my duty to serve my country first and therefore, I gave it free to the Indian Government.” What he laments is the slow progress, “the plastic binding with bitumen is an ideal option for roads that bear the brunt of torrential rains.” Also, he underlines, if citizens treat their waste properly by segregating and collecting the plastic, the country will soon be free of plastic litter and boast safer and better roads.

His department is now evolving a cold process technology as well. The Department of Science and Technology has sanctioned a ‘green chemistry' project at TCE for producing a 'cold emulsion' to coat the aggregate instead of using hot bitumen. Such a process would be highly useful in laying roads in cold regions. Widener University, Philadelphia, has already shown interest in the cold process.

With a low- cost technology that finds a ready solution for plastic waste management, Dr. Vasudevan's invention undoubtedly offers a lesson for all municipal corporations. “It serves the twin purpose of increasing quality of roads and also solves the problem of plastic disposal. The vision should be to eventually replace all existing roads and lay every new road with this technology,” says the professor.

THE BENEFITS

Low cost (using less bitumen)

Simple technology

Spot use of waste plastic

Water proof roads that last up to 60 years

Doubling of road strength

Higher load- carrying capacity

Almost zero maintenance

A new surface without rutting, cracking or potholes.

PLASTIC ROADS LAID

With the TCE's patented technology under Dr. Vasudevan's guidance:

The first ever plastic road (60 feet long) was laid inside the TCE campus in 2002, followed by a 700 m road in Lenin Nagar, Kovilpatti, the same year.

Officially, the industrial town of Salem was the first in the country to lay a 350 m road on an experimental basis using plastic tar technology in 2004.

In Tamil Nadu, the District Rural Development Agency laid 1,200 km of plastic roads in 29 districts across the state under the TN Urban Local Bodies Road Development Project 2005.

One km towards Vilacheri from near Mannar Thirumalai Naicker College, Madurai, in March 2005. Sri Sundareswara Vidyasala Matriculation Higher Secondary School at Attukulam village near Melur , Madurai, has a road entirely laid with plastic waste collected by the students.

Several plastic roads were laid in Wellington, Chennai, Puducherry, Hindpur (Andhra Pradesh), Kolkata, Goa, Mumbai, Shimla, Thiruvananthapuram, Vadakara, Calicut, Kothamangalam and Kochi) in the last few years. Plans are afoot to lay demonstration roads in Hyderabad.; Mumbai Municipal Corporation now proposes to lay longer stretches of tar-polymer roads across Mumbai. The Jamshedpur Utilities and Services Company, a Tata enterprise, approached Dr. Vasudevan last November for using plastic waste in laying roads in Jamshedpur

THE PATENTED PROCESS

The gravel is heated at 170 degrees C and shredded plastic sprayed over the hot stone aggregate. The plastic instantly melts and coats the gravel without releasing toxic gases into the atmosphere. Immediately, bitumen heated at 160 degree C is mixed at 155 degrees C and used for laying the road. Molten plastic with liquid tar has proven to be more resistant to water permeation, heat and high pressure than the normal mixture of stone aggregate and bitumen, without the plastic

WHAT IT TAKES

To lay one km of plastic road 3.75 m wide, 9 tonnes of bitumen and 1 tonne of waste plastic are required for coating. A normal road requires, 10 tonnes bitumen for each kilometer. So a plastic road saves 1 tonne bitumen for every kilometre laid. Each tonne of bitumen costs Rs. 50,000 to 60,000. One tonne of plastic waste is equivalent to 10 lakh carry bags. Chocolate and biscuit wrappers, tea cups, polythene bags or any other form of waste plastic, can simply be shredded and used. Different types of plastics collected need not be segregated. To make enough plastic available, people need to sell their domestic plastic wastes instead of throwing them into the dust-bin. Nearly 4,000 self-help groups and hundreds of schools in Tamil Nadu are now involved in collecting and shredding waste plastic.

With the TCE's patented technology under Dr. Vasudevan's guidance:

The first ever plastic road (60 feet long) was laid inside the TCE campus in 2002, followed by a 700 m road in Lenin Nagar, Kovilpatti, the same year.

Officially, the industrial town of Salem was the first in the country to lay a 350 m road on an experimental basis using plastic tar technology in 2004.

In Tamil Nadu, the District Rural Development Agency laid 1,200 km of plastic roads in 29 districts across the state under the TN Urban Local Bodies Road Development Project 2005.

One km towards Vilacheri from near Mannar Thirumalai Naicker College, Madurai, in March 2005. Sri Sundareswara Vidyasala Matriculation Higher Secondary School at Attukulam village near Melur , Madurai, has a road entirely laid with plastic waste collected by the students.

Several plastic roads were laid in Wellington, Chennai, Puducherry, Hindpur (Andhra Pradesh), Kolkata, Goa, Mumbai, Shimla, Thiruvananthapuram, Vadakara, Calicut, Kothamangalam and Kochi) in the last few years. Plans are afoot to lay demonstration roads in Hyderabad.; Mumbai Municipal Corporation now proposes to lay longer stretches of tar-polymer roads across Mumbai. The Jamshedpur Utilities and Services Company, a Tata enterprise, approached Dr. Vasudevan last November for using plastic waste in laying roads in Jamshedpur.

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