Team:IIT Delhi/Biotoilet




Conventional toilets used in Indian Railways pose a few problems. They dump waste onto tracks which causes corrosion and creates safety risks. They also create unhygienic situations as these toilets are mostly used when trains are stationary or platforms. Owing to the sheer quantity of waste, even cleanliness is a major sticking point with officials. A Decent Toilet

Biotoilets which have jointly been developed by the Railway Research Design and Standard Organisation and Defence Research Development Establishment are being viewed as possible replacement for conventional toilets. Bacteria treat waste and the final output, according to the officials, is just water and gas. Officials say that the design of the system would ensure that there is zero discharge of waste onto train tracks.
Bio-toilet Plan

Scientists at IIT Kanpur, however are skeptical of the claims of Railway officials. They conducted their own tests and came to the conclusion that the system is not as efficient as it is being portrayed. (Insert link of study) Despite the studies done by IIT Kanpur, The government of India is going ahead with its plan to implement biotoilets in trains all over India.
We became interested in the studies done at IIT Kanpur and decided to contact Prof. Vinod Tare, who's part of the team which has done studies to see the efficiency of these bio-toilets, to learn more about the proposed mechanism and the tests being done at IIT Kanpur. Below are excerpts from our concersation:

1) What is the mechanism of bacterial degradation of excreta?
Biomethanation. The bacteria convert the organic matter into methane and water in anaerobic conditions. This is a standard biochemical process and used widely in various other fields.

2) What were the results of the experiments that were done to test the efficiency of biotoilets?
The tests revealed that the BOD/COD of the organic waste, after treatment, was much higher than what has been claimed by DRDO and that there were coliforms present in the effluent, which was only removed after extensive chlorination (this being highly oxidative in nature, would cause even more corrosion of railway tracks athan is already caused).
There was also release of gases, harmful for the environment. Prof Tare also said that the bacteria requires certain conditions to grow and it was impossible to maintain those conditions throughout.

3) Where have these bacteria come from? Are they genetically Engineered?
No. They are not genetically engineered strains. In fact, these bacteria were isolated from Siachen, where they were being used for degrading faecal matter. They were adapted to conditions in the compartments by selection.

4) Can so much amount of waste be treated so quickly in these compartments below the trains?
There exists no Magic bacteria that can achieve this. The claims of DRDO about the waste being able to get treated within hours are false and misleading.

5) Is there any safety threat if these bacteria are released in the environment?
Although this question wasn't answered clearly, it seems very unlikely that mere presence of these bacteria in the environment can cause anything bad as they are most likely non-pathogenic. However, the effluents of the biotoilets may very well be harmful to the environment and NOT AS GREEN AS THEY ARE SHOWN TO BE.

Feel Free to contact us at igemiitdelhi2013 at gmail dot com if you have queries; requests; suggestions et cetera.

Thanks to iGEM and IIT Delhi,
we had an awesome summer!
Our Project was supported by and done by the students

 of IIT Delhi, India.

This project was done as a part of iGEM:
iGEM Main Website