Tamil Nadu's Bhopal - or how Unilever dumped Mercury waste

I wandered into reading on Tamil Nadu's Bhopal - or how Unilever dumped Mercury waste on Kodaikanal's pristine environment for 18 years..  and refuses to clean up even after it was forced to shut down its factory in the wake of the public uncovering of its dumped waste.

Kodaikanal is a hill station at 7000 feet on the Palani Hills in Tamil Nadu. It is part of the Shola eco system across Karnataka, Tamil Nadu and Kerala, which itself is a part of the Western Ghats.

Its hills are always kissing the clouds resulting in a high amount of precipitation.. the trees are short due to high winds, and there are extensive grasslands.. which make this ecosystem unique.

Mercury is one of the most toxic elements known. Ponds moved its factory  (later acquired by Unilever)  to make mercury thermometers from New York to its present site in 1983 as the temperature was low year round.

Legislation on mercury handling in the U.S. had begun to change after toxic side effects began to be publicised. The Ponds India management got special permission from the Central government in India to set up at Kodaikanal on the grounds that it was a non-polluting glass manufacturing unit (!). No formal site selection or screening process was undertaken to assess and minimise the impact of a mercury thermometer plant in an eco-sensitive area.

The Tamil Nadu Factories Inspectorate and the Pollution Control Board found nothing amiss in their periodic inspections of the factory including on workers' health. In 2001, it was citizens - the Palani Hills Conservation Council and Greenpeace, which caught the management selling mercury-contaminated glass to a local scrap dealer. Faced with the evidence, the Tamil Nadu Pollution Control Board asked the factory to close.

Toasted Pineapple !

I have always loved pineapple. I was introduced to it in my teenage years but only pieces from a can. After I was married and experimented with food in my kitchen, we started having raw, fresh bought pineapple. But we usually had to put it in a sugar solution or add cheese.

Else the raw pineapple would give me a bad throat leading to flu sometimes. But when out eating at Barbecue Nation with my father perhaps a couple years ago, we were served with lots of baked pineapple smeared with oil, salt and red chilly. It was va-va-voom !

Now we bake cut pineapple pieces in our oven regularly - no oil, but with some salt and chilly smeared on it. 7-8 minutes in the oven is enough.

Apparently, there are tremendous benefits from eating pineapple : https:/ including for asthma, cancer, blood pressure and diabetes.

On sharing the above information on whatsapp with friends, the following exchanges were interesting.. Friend 1 : 'Try grilling it ; you will love it more.' Me : 'Smile.. well the oven has the heating rod on above and below. That setting in my oven is called 'toast'.'

Friend 2 : 'Yeah you can do it in a pan too. If it’s a bit tart, few sprinkles of sugar gives nice caramelising and smokiness. Oven is more like cooking through and pan depending on heat is either cooking through or just charting and caramelisation.' Me : 'Ah !'

Friend 3 : 'Pineapple is a great food all round- like papaya it has a good digestive enzyme and it's great for metabolism. But like you I have some difficulties with it. It's almost always too tart for me and causes mouth ulcers, rashes, sore throat, tummy ache, etc.

It's the reason I love pineapple on pizza because its one of the few times I can eat it. But your idea of baking it is interesting and I will try it when I get back to Oz. When we were in Egypt many years ago, the hotel had fantastic breakfast buffets including lots of pineapple.

To my delight, the pineapple was uniformly so sweet that I had no difficulty eating it at all and ate lots every day. Have never encountered pineapple like that since even though Queensland is a big pineapple growing state in Australia.'

Me : 'Yes.. such sweet pineapple in india is only from Kerala in my experience.. no problem eating it raw there !' Friend 4 : 'But cooking fruits spoils vitamins.' Me : 'Not necessarily, as these links would show you : here, and here.

I think toasting for 7-8 minutes would deliver only as much heat as steaming for a few minutes so loss of nutrients should be minimal.
Besides, vegetables too lose some nutrients in cooking, while gaining some others. But we do cook them, dont we ?

Lastly, I would fall sick if I had raw pineapple in Delhi (though it is fine for me in Kerala). So I have no other way to eat it !'

The Pioneers - Indian Cities using Plastic Waste in Bituminous Roads

Chennai

Chennai is one of the first and leading cities in India to implement professor Vasudevan’s technology. It has, so far, used 1.6 Lakh kilos of plastic waste to build 1,035 kilometres of roads. Prominent areas in the city like the N.S.C Bose road, Halls road, Ethiraj Silai street and Sardar Patel street are laid with plastic components.

The Guardian wrote in 2016 : 'Jambulingam Street, Chennai, is a local legend. The tar road in the bustling Nungambakkam area has weathered a major flood, several monsoons, recurring heat waves and a steady stream of cars, trucks and auto rickshaws without showing the usual signs of wear and tear. Built in 2002, it has not developed the mosaic of cracks, potholes or craters that typically make their appearance after it rains. Holding the road together is an unremarkable material: a cheap, polymer glue made from shredded waste plastic.'

“Jambulingam Street is the best I have ever seen in the city so far. When many other roads in the city got damaged, this plastic road has remained in good condition for many years,” said N.Chidambaram, an autorickshaw driver in the locality.

Tamil Nadu as a whole has some 20,000 kms of plastic roads, mostly rural ones. A modified version of the road which adds road scrap to plastic-coated gravel was tested out in 2016 on a highway connecting Chennai with Villupuram. It was the first time plastic road technology was used for a national highway. It is expected to reduce construction costs by 50%.

It was announced in Jan 2019 that Madurai, Chennai and Thiruvananthapuram airports to get roads made using plastic waste in a pilot project. Recycled waste will be mixed with bitumen to lay roads. Experts say the technology will ensure that the road made with the waste will not need any maintenance for 15 years. 

As per the plan, the material will be laid on roads within the airport premises first, and then perimeter roads along the compound walls will be laid. If successful, the technique will then be used for taxiways in the airport.

Officials said that since the Chennai airport generates the highest quantity of plastic waste in the region, this could be a good use case for the project.


In New Zealand, the Christchurch International Airport has paved its airport's fire station's premises using recycled plastic and bitumen.

Pune

Pune, which produces more than 200 tonnes of plastic waste each day, has used 3,343 kilos of plastic waste in building 1,430 kilometres of roads in the last two years. The Pune Municipal Corporation tied up with the Rudra Environmental Solution (India) Ltd and gave them a contract of building plastic roads across the city.

Vishakhapatnam

Taking a step further towards becoming a smart city, the municipal corporation had mooted this project in 2016 when they had laid 10 roads across all its zones. In 2017, till December, 16 more roads were completed. The length of various stretches ranged from a few metres to three kilometres. The aim is to construct more and more roads from plastic waste waste wherever re-laying of roads is required and plastic waste is available. 

Indore

Two-time winner of India’s cleanest city title, Indore recycles 100 per cent of its plastic waste and has used 5,000 kilos of waste plastic to build 45 kilometre stretch of roads in the last two years. 'The strength and finishing of roads when waste plastic is used is much better than tar. These roads have a better resistance to water stagnation. We noticed that areas in Indore where plastic was used to build roads saw less water clogging during monsoons as the roads didn’t develop potholes. In other words, the life span of the road is substantially increased', said the Swachh Bharat Mission Consultant, Indore Municipal Corporation.

Surat

Surat finally heaved a sigh of relief during monsoons last year. The idea of using plastic-bitumen mix was executed in January 2017. The diamond city has used 90,000 kilos of waste plastic to lay 15.91 kilometres of roads. The problem of potholes significantly reduced last year as no cracks developed in areas where roads were layered with waste plastic says Akshay Pandya, Executive Engineer, Road Development Department, Surat Municipal Corporation.

Lucknow

The Lucknow Development Authority (LDA) is constructing a 10 km long road, from Gomti Nagar Police Station to the Indian Institute Of Management Lucknow, using plastic waste. Padmashri awardee and reputed Scientist Rajagopalan Vasudevan, also known as the ‘Plastic Man Of India’ will be leading the project.

According to the project’s Chief Engineer, Indushekhar Singh, mixing plastic waste increases roads’ durability by 40-50 per cent. “We use less than 50-micron plastic and around 8-10 per cent of plastic waste is being mixed in coal tar”, he added. 

“LDA will be following all the guidelines of the Central Road Research Institute in the construction of this road,” Singh said. Singh, told the media, “The process doesn’t require any complex machinery. It just needs to segregate plastic waste to a particular size, heat it and mix it with bitumen to bind it.” 

“Using plastic waste can help India, which has the world’s second largest road network, in reducing road accidents deaths. Potholes, a common feature of roads in India, are responsible for one-tenth of deaths that occurred in 2017 due to road accidents in the country”, professor Vasudevan explained to the media.

Why Waste Plastic Composite Roads are Better than Bitumin Roads Alone

India has built one lakh kilometres of roads in at least 11 states using discarded plastic. 

Plastic-bitumen composite roads have better wear resistance than standard asphalt concrete roads. They do not absorb water, have better flexibility which results in less rutting and less need for repair. Road surfaces remain smooth, are lower maintenance, and absorb sound better.

Roads constructed using waste plastic are durable against extreme weather conditions, are cost-effective and pothole-resistant says World Economic Forum.

The plastic tar roads in Chennai have not developed any potholes, rutting, raveling or edge flaw, even though these roads are more than four years of age, read a performance report by India’s Central Pollution Control Board.

Adding flexible materials to strengthen tar roads is not a new idea. Commercially made polymer-modified asphalts first became popular in the 1970s in Europe. Modified asphalts are made from virgin polymers and sometimes crumb rubber (ground tires).

Polymerized asphalts also tend not to buckle in extreme heat the way conventional roads do – plastic roads will not melt unless the temperature goes beyond 66C, compared to 50.2C for ordinary roads – and are frequently used on roads in the Middle East.

But even in the US, cost is a significant barrier. The most widely used polymer, styrene-butadiene-styrene, can increase the price of a road by 30-50%. In India, high-stress roads like runways and expressways are increasingly using polymer modified asphalts made by manufacturers like DuPont. 

While polymer roads in the US are made with asphalt that comes pre-mixed with a polymer, plastic tar roads are a frugal invention, made with a discarded, low-grade polymer. 

The Process of Making Composite Plastic Roads

A city’s plastic waste is put through three tasks – cleaning, drying and shredding. The plastic waste can include anything from sweet wrappers to shopping bags.

Once all the plastic waste is shredded (a technique where all the dust particles are eliminated, and plastic items are shredded into fine pieces) these are heated at 165°c. Next, the shredded pieces are added to bitumen mix, which is also heated at 160°c. The final mix is used for constructing roads.

The inventor of the process, Vasudevan melts shredded plastic over low heat to avoid emissions (Dr Vasudevan was honoured with one of India’s highest civilian awards, the Padma Shri, for his groundbreaking research on re-using waste plastic). Polystyrene is toxic when burned but, when softened, it makes an excellent pothole filler.

“Depending on the quality of tar, a 10-30 per cent of it is replaced with the waste plastic. Since both, tar and plastic are petroleum products they gel well together,” said Asad Warsi, Swachh Bharat Mission Consultant, Indore Municipal Corporation.

Every kilometer of a plastic tar road uses the equivalent of 1 million plastic bags, saving around one tonne of asphalt and costing roughly 8% less than a conventional road. 

In experiments to find uses for discarded plastic, Dr. Vasudevan found that in a molten condition, plastic had the property of an excellent binder. Acting on the principle that like attracts like, Dr Vasudevan looked at another chemical of similar nature: bitumen, a black tarry substance that was being combined with gravel to lay roads.

“Bitumen, a highly heterogeneous mixture of hydrocarbons is in effect, composed of polymers similar to plastic,” he says. When molten plastic was added to stone and bitumen mix, Dr Vasudevan found that, true to its nature, plastic stuck fast and bound both materials together.

The bitumen-modified plastic improved the tensile strength of the road by making it more durable and flexible. Plastic also prevented pothole formation. When the layer of molten plastic filled the space between the gravel and bitumen it thwarted rain water from seeping in and causing structural defects.

When late Dr Abdul Kalam, India’s former president and scientist visited Thiagarajar College, he encouraged Dr Vasudevan to lay the first plastic paved road within the campus. In 2002, he paved a 60-ft road within the campus with plastic-modified bitumen. The road is still intact in 2018.

In 2013, The Indian Road Congress developed Guidelines for the use of waste plastic in hot bituminous mixes (dry process) in wearing courses.

The guidelines state that studies have revealed that waste plastics have great potential for use in bituminous construction as its addition in small doses, about 5-10%, by weight of bitumen helps in substantially improving the Marshall stability, strength, fatigue life and other desirable properties of bituminous mix, leading to improved longevity and pavement performance. The use of waste plastic thus contributes to construction of green roads.

Only plastic conforming to Low Density Polyethylene (LDPE), High Density Polyethylene (HDPE), PET and Polyurethane shall only be used in pavement construction.

Environmental Advantages of using Waste Plastics in Bituminous Roads

India produces about 15,000 tonnes of plastic waste daily, of which about 9,000 tonnes is recycled. The remaining plastic is either burnt leading to air pollution, ends up in landfills or clogs drains.

“Ban plastic and it can severely affect the quality of life for a low-income family,” Dr. Vasudevan says. “But if you burn it or bury it, it’s bound to affect the environment.”

Landfilling and incinerating plastic are both problematic methods of managing plastic waste. Plastics in landfills can leak pollutants into the surrounding soil; incinerating creates gaseous pollutants, such as carbon dioxide.

Plastic roads can be built from waste plastic - the majority of which is usually put into landfill, incinerated, or polluted into the environment. 

Plastic-bitumen composite roads need not be especially discriminating with the plastics used, thus increasing the reuse of plastic. Most plastic waste is not recycled because it is usually mixed with different types of plastic and non-plastic and, so far, the segregation process is labor-intensive with no easy solution. 

Using less asphalt saves on resources. Asphalt concrete requires petroleum which is becoming scarcer.

The addition of plastic in asphalt can reduce the viscosity of the mix. This allows a lower working temperature, which lowers VOC and CO emissions.

Cost effective: using recycled, post-consumer plastics is cheaper than using asphalt.

“Our planet is drowning in snack-food packaging that is non-recyclable,” says Almitra Patel, a member of India’s supreme court committee for solid waste management. “If (this technology is) seriously adopted in all cities for all multi-film laminates, it has the potential to achieve near-zero landfill, leaving almost nothing for final disposal.”

To environmentalists who believe that the technology could be harmful because of toxic fumes from plastic residue, Dr Vasudevan points out that the plastic used is softened at 170C. “Plastic decomposes to release toxic fumes only if it is heated at temperatures above 270C. So there is no question of toxic gases being released,” he says. Since plastic coats the stone and interacts with the hot bitumen, it’s properties change and it doesn’t break down when exposed to light and heat.

In 2018, trashing the oft-held view bandied around by plastic-sceptics, Vasudevan Rajagopalan said it is not plastic per se but the woefully inadequate waste management system which leads to the accumulation of plastic debris on both land and in water. "Plastic is a valuable resource," he said while inaugurating the National Conference on Marine Debris at Kochi.

More than 90 per cent of all plastics use oil as feedstock. It currently stands at 5 per cent of the total oil consumption and will use 20 per cent by 2050. In the end, the solution lies in a circular economy.

Non-segregation of waste at source is the biggest hurdle to plastic recycling and waste management in India.

Plastic Roads will change India

Types of waste plastic usable in road making

The technology for using waste plastics in tar roads has been developed by Dr. R Vasudevan and his team in Madurai, Tamil Nadu at the Thiagarajar College of Engineering. His contacts are given in the video description. 

50 percent of all plastic waste in India is used for packaging which is particularly amenable for road making. Multi-film sachets, foils, PU foam, thermocol can all be shredded and used together in bitumen roads. 

How plastic roads are made

For Normal roads, bitumen is added to heated stone and laid on the surface of the road space. For plastic roads, shredded waste plastic is added to heated stone such that the plastic melts and forms a layer on the stone. Bitumen is then added to this mixture which is then laid on the surface of the road space. The plastic acts as a strong binder between stone and bitumen. Such a road is nearly twice as strong as a normal road and highly durable. Water does not penetrate inside and peel away the bitumen like in normal roads. 

Government support to plastic roads

The first plastic road was laid in Tami Nadu in 2002.  By now, 20,000 kms of rural plastic roads have been laid in Tamil Nadu. The National Rural Roads Development Agency uses this process  to make 5000 kms of roads in India a year. A Government of India notification of Nov 9, 2015 directs that plastic roads will be laid in all urban areas wherever population exceeds 5 lakhs. 

Indian Roads Congress SP 098 of 2013 details the use of waste plastic in hot bituminous mixes (dry process) in wearing courses.

In Plastic Roads, one-tenth of bitumen is saved per km - worth about Rs. 50,000. We are able to use 1 ton of waste plastic per km of plastic roads - that equates to 10 lakh thrown carry-bags ! 

The 40 lakh kms of roads in India can use up all our waste plastic. Only 20 % of Indian roads are black-topped and there is huge scope for improvements in road transport infrastructure using the plastic roads technology. 

Much better pothole repairs too can be achieved by adding 3-5 % shredded thermocol to hot bitumen.

Scientific instruments used to test the process

The road in this video looks like it may have been built just six months ago. But it was actually built in 2002 ! It employed a process where shredded waste plastic substituted  for 10 % of the bitumen. Multifilm, foil, all types of waste packaging plastic can be used for making such a road after shredding into 2-4 mm sized pieces. PU Foam, which today forms a large component of packaging, can also be shredded and added. So can thermocol. 

The Chemistry lab at Professor Vasudevan's department has acquired machines which assisted in the development and testing of this process. 

These machines include the compression testing machine, a marshall stability value testing instrument to test stability of roads, a bitumen penetrometer to test bitumen, etc. 

There is also a computer lab of the chemistry department which has instruments like the thermo gravimetry analyzer, differential scanning calorimeter, optical flouroscent microscopy, fourier transformed infra red spectroscopy, brook field viscometer, etc. 

A patent has been awarded to the Thiagarajar College of Engineering for the plastic roads process.

Smart india needs smart roads

The technology for the use of plastics in road has been developed by an Indian, in India, for use in India. 

The Tamil Nadu Government set up self-help groups in every district to gather plastic packaging wastes. The Government has given loans to such self-help groups to purchase shredding machines. They shred the collected plastic and keep it ready for the Government to purchase such plastic from them for road making. 

This technology can help make the best use of scarce fossil fuel resources and waste plastic packaging that currently clogs up India’s water channels and spoils our land. 

Smart India needs Smart Roads. Smart Roads can be made by adding waste plastic to them. So waste plastic packaging can be a useful resource for India as long as it is kept segregated, collected and stored at a central place for shredding and adding to roads. If the home and its surroundings are clean of plastic packaging waste, the city is that much cleaner. 

Every citizen who complains of a dirty street or a dirty country can begin in their home with keeping their dry waste separate and giving it separate.