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Showing posts with label plastic. Show all posts
Showing posts with label plastic. Show all posts

Wednesday, September 25, 2019

Plastic Roads will change India


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.

Tuesday, October 23, 2018

Making compost in 50 days from Day 1 of putting wet waste in the compost bin !

Khad (compost) from our compost box has been working well since about March 2018. No food waste is now given out to trash. Our earlier knowledgeable farmer housekeeper said it was as good as gobar ki khad (cow dung manure).

We are sold the composting bin by a local industrialist as part of his philanthropic work, for about 250-300 rs. a set, as I recall : 1. a re-used industrial bin which has been perforated on all the sides including top and bottom. 2. a bag of coco-peat which comes from the coconut tree. 3. a panja to turn the waste with.

Close up of the perforations in the compost bin..

Here's our kitchen waste, ready to be put into the composting bin. we leave out only narial ka khol (coconut shell), aam ki gitak (mango seed) etc. as they would take too long to compost. Those are bagged and put out to the waste collector when bag is full. but they are not mixed with dry waste such as paper, plastic, rubber which is easily sale-able and collected in a big bag until brimming full, then tied a knot on and put out. We dont use plastic bags as lining for kitchen waste. cut newspapers do the job perfectly well.

When starting out a new bin, one puts two fist-fulls of the coco-peat at bottom.
One empties the wet waste bin in the composting bin. one then washes and leaves the wet waste bin to dry. the second wet waste bin, already washed and put to dry the previous day, is put in the kitchen.
One then adds a fistful of coco-peat to the wet waste.
One mixes the coco-peat into the wet waste using the panja provided. one closes the bin cover. at our place, the bin is full in about 20 days. the wet waste in the  is then given a good mix up with the panja and left to the side somewhere where too much rain cant get into it. In about a month, it looks mature and black the way you saw in the first image.

we then normally put the compost in our plant pots and kyaris where it composts further. you can turn the soil a bit to hide it if you like.  We dont need to dry the compost as you saw in the first picture. we were drying it this time only to use it like the coco-peat bag - so one need not source coco peat again and again. one can just use the dried compost as a base layer and then to add a fist full everytime you put wet waste in the composting bin.

so at our rate of generation of wet wastes (two of us + 1-2 staff + guests over perhaps once a week), we need three compost bins which we have. but a family with less number of people to cater to, would still need two compost bins if they dont want to throw any wet wastes out, which we dont.