No more smelly toilets to spoil train travel

CHENNAI: If the Integral Coach Factory has its algorithm right, there will very soon be no smelly toilets on trains. This innovation should make train travel a more pleasant affair. But the absence of smell is only the by-product. The new bio toilets developed by Railways design engineers will do away with manual scavenging on trains and add to the life span of the tracks. The new toilet will have a collection tank fitted with anaerobic bacteria to decompose faecal matter completely. What is released at the end is a colourless, odourless, benign liquid that does not pollute the environment. The revolutionary toilet is the result of a joint effort by the Defence Research and Development Establishment and Indian Railways. The DRDE provided the anaerobic bacteria that they had developed and used successfully in Siachen.The mechanism functions thus: The bacteria, secured to the walls of the tank, are most active at temperatures between five degrees and 30 degrees Celsius and feed on faecal matter. The tank has seven chambers and by the time the excreta traverses through the chambers and reaches the exit, it is fully decomposed. The resultant water passes through a chlorine chamber to control its pH level and the microbe content in it.For about a year now, 44 toilets in 23 coaches of the Guwahati-Chennai Egmore Express have been fitted with these bio tanks. The performance of these toilets was being monitored jointly by the DRDE and the ICF. The coaches were commissioned in October 2011.“The feedback is positive. We are going to roll out 1,200 toilets in our new coaches in 2012-13,” said S Srinivas, chief design engineer, ICF.Before arriving at the design, the engineers tested several models of bio toilets. “We wanted something simple and effective. The problems we face with the choking of toilets are a big challenge. We needed a technological solution,” Srinivas said.To handle choking, the tank inlet has been provided with a valve near the P-trap. The valve can be manually operated to clear the choke. Other variants of the bio toilets, especially ones that recycle waste water for reuse, are under trial.