defence scientists have recruited a small army of bacteria and
harnessed solar power to build bio-toilets for managing the human
waste of soldiers stationed at glaciers and other low temperature
"Human waste disposal in high altitude and low temperature areas
is a burning problem," a spokesman for the Defence Research and
Development Establishment (DRDE) in Gwalior told IANS on phone.
"The problem is further aggravated in glaciers where ambient
temperature drops to minus 40 degrees Celsius and lower."
When left buried in the ice, the low temperature prevents natural
biodegradation of waste, leading to their accumulation for a long
time. Due to heating by direct sunlight, the melting ice takes the
waste to rivers, polluting them as well, scientists said.
Traditional methods of burying human waste or incineration and
chemical treatment are not possible in glaciers. Biological
treatment is an attractive approach for solving the problem but
micro-organisms that decompose the waste in normal temperatures
are inactive at freezing temperatures.
Technology developed by DRDE overcomes the problem.
The key to DRDE's bio-toilet technology is a consortium of
anaerobic bacteria --organisms which do not require oxygen to live
and multiply -- that has been formulated and adopted to work at
temperatures as low as five degrees Celsius, the scientists said.
The bacterial consortium acts as inoculum (seed material) to the
biodigester converting the organic waste into methane and carbon
dioxide. The biodigester buried below the ground serves as a
reaction vessel whose temperature is maintained between 5 and 30
degrees Celsius by solar heating. Charging of the biodigester with
the bacterial inoculum is done only once during the entire life of
DRDE scientists say their technology allows the human waste to be
disposed of in an eco-friendly manner in places with extremely low
temperatures. They claim their process results in treated effluent
free from pathogens, and biogas (methane) is generated as a
byproduct, which can be used for cooking and room heating.
According to scientists, the biodigester developed by DRDE is
suitable for below zero temperatures of the Himalayan region and
is maintenance free. Around 90 DRDE bio-toilets have been
installed at 24 locations, including several places in Leh, Sikkim
and at the Base Camp in Siachen glacier, DRDE said.
The scientists said as a spin-off, the same technology has been
used to develop bio-toilets for Indian Railways. These toilets
were successfully run on the Gwalior-Barauni Mail for two years
and the technology has been transferred to eight firms, scientists
Jayaraman can be contacted at email@example.com)