Can you please send me some information and details
regarding the biogas plant set up in Kolkata?
Dear Aarti Ji,
Low cost mini-biogas digesters, suitable for small family units, are
being set up in Kolkata. The digester, which requires about 12 kg of
cattle dung per day, is designed from low cost materials and can be
installed at one-third the cost of conventional biogas plants.
installation cost of this 0.5 cubic metre single mini-biogas plant
is about Rs 2000 while that of a two cubic metre biogas plant is Rs
6000. The digesters are exclusively designed for lighting purposes.
The vertical cylinder body of the mini-digester, made of
pre-fired earthen rings generally used in lining wells, has inlet
and outlet pipes made of asbestos cement. When fed with cattle dung
the digester produces 0.5 cubic metre biogas per day sufficient for
four hours of lamp use.
I have read
that diesel exhaust is quite harmful. But how does bio-diesel
compare to it (especially in the amounts of particulate matter,
nitrogen oxide, low level ozone etc)?
Sabarish Sasidharan (Sab)
The use of biodiesel in a conventional diesel engine results in
substantial reduction of unburned hydrocarbons, carbon monoxide, and
particulate matter compared to emissions from diesel fuel. In
addition, the exhaust emissions of sulfur oxides and sulfates are
Emissions of nitrogen oxides are slightly reduced or
slightly increased depending on the duty cycle of the engine and
testing methods used. Based on engine testing, using the most
stringent emissions testing protocols required by EPA for
certification of fuels or fuel additives in the US, the overall
ozone forming potential of the speciated hydrocarbon emissions from
biodiesel was nearly 50 percent less than that measured for diesel
This chart compares Bio-diesel emissions with that of
How much of the wastewater generated from Kolkata goes to the East
Kolkata wetlands area?
Dear Tania Ji,
Kolkata produces about 1,350 cm of sewage every day containing 2,076
tonnes of suspended solids, virtually all of which is absorbed by
the East Kolkata wetlands, a site recognized under UNESCO’s Ramsar
Convention of 1971.