Dear Pandit ji, I am a regular reader of Gobar Times and I like it a lot. I like the simplicity of the language; especially the way information is given through graphs and pictures. I got a lot of information particularly from the last issue. I never realised the quantity of water we waste everyday in our toilets. Even the ‘Indicab’ article was great. I have one more request. Instead of an alternate supplement, please make Gobar Times a regular supplement. Geeta Sharma Mysore, Karnataka Dear Pandit ji, I am a student of class IX and a regular reader of Gobar Times. I like the way the magazine is presented to us with so many good photographs and posters, and the language is easily understandable. I want to tell you that my father runs an organisation named Pahal, which works for the environment by doing activities like tree plantation, water harvesting and so on. I think I am old enough to make an of Pahal named ‘Junior Pahal’. But I am a little confused about the kind of environmental activities that can be done by the children of my age. Can you please help me? I also want to work for Gobar Times. Please tell me what can I do for your magazine. Liakatbir Singh Jalandhar, Punjab Dear Liakatbir Singh ji, ‘Pahal’ means ‘first initiative’. So, your organisation is also a ‘pahal’. You may organise eco-tours of Jallandhar. Track the flow of waste from your neighbourhood or school to the main dustbin where it is disposed off. A wastewater tour is another interesting idea. Share the findings and feedback of the “tour-partners” with the people in your neighbourhood or school. You may check out the Green Schools Programme manual of CSE. It is about students going around their school and generating its report card on management of resources. Find out more about it on: http://www.cseindia.org/programme/ eeu/gsp/gsp_index.htm Visit the following websites to know more about how young people, like you, can set up their own ventures: www.younginfluencers.com www.changemakers.org.uk

Floating gas-holder type of plant:
A well is made out of concrete called the digester tank T, which is divided into two parts. One part is an inlet, from where the slurry is fed to the tank. The cylindrical dome H of the tank is made out of stainless steel that floats on the slurry and collects the gas generated. Hence it is called floating gas-holder type of bio gas plant.

The slurry is fermented for about 50 days. As more gas is made by the bacterial fermentation, the pressure inside H increases. The gas can be taken out from outlet pipe V. The decomposed matter expands and overflows into the next chamber in tank T, which is removed by the outlet pipe to the overflow tank and used as manure for cultivation purposes.

Fixed dome type of plant:
A well and a dome are made out of concrete called the digester tank T. This dome is fixed and thus it is called fixed dome type of bio gas plant. The function of the plant is similar to the floating holder type bio gas plant. The used slurry expands and overflows into the overflow tank F.

Advantages and disadvantages:
In the floating gas-holder type of plant, the floating chamber is made of stainless steel. This is expensive and needs continuous maintenance and supervision for non-rust. This does not arise in the fixed dome type of bio gas plant as everything is made of concrete.

The volume of fixed dome type of biogas is fixed. So if the gas pressure increases inside, it may cause damage to the concrete dome. This does not happen in the floating holder type of bio gas plant.

Check out their diagrams.