Compost Preparation

Hi Everyone,

We have around 4 cows at our home in a village. Just wanted to know how to prepare compost/manure out of cow dung. Exact steps on pit size, composition, etc will be helpful. We have vast space for pit digging and for other maintenance.

Thanks in advance.

Hi Prasath

Check this link below. … t-jal.html

Dear Prashanth,

I have a sugestion for you.

You can build a biodigester. In Karnataka Shimoga,Mangalore,Uttarkannada district farmers are already using this and found best results.

Actually it is called Rasavari Tank or Jeevasara Unit.

See link

It works like this. Fill cow dung,urine, green leaves, tree dropplings etc in a tank of 10’x6’x’4. Keep this tank shaded. Within a week liquid manure is ready. You will needs a secondary tank for collection and filtering. Pump it to main tank of water or join it drip system or connect venure to secondary tank. You have multiple option.

Filled organic matter will reduce as the time passes. It has to be refilled as it decreases. Once in six months entire tank must be emptied and dried.

This concept has minimum labour efforts and the fertilizer is directly reached to root zone. This can be operated by one labour.

I am  studying on this. I will design and build and post pictures(it may take more than six months). I am doing this activity from a long time because I am visting many farms  to see different constructions. Each one has their own designs.
I am importing design of sludge drying bed for this tank to have a natural filtering system.

People use this liquid manure once in a week with drip irrigation. Last month I visited one farm his arecanuts yeild increased 16 to 22 quintals after changing from conventional fertiliser feeding to bio-digester system.

The vedio link posted above is athe example of a Banana farmer. He grows banana with chem fertilisers for first 5 months later he uses bio digester water every day. This is phenamonal development. When people say Banana cannot be grown organically in commercial scale, this farmer has achived it. He is going for 100% organic from next replantation.

Second such option is Vermiwash.
It is nothing but vericomposting,  The pit will have effluent pipe whcih releases excess water from pit. it is collected/filtered and mixed with drip irrigation.

The point I am still figuring out is “how to handle Methane gas released from Biodigester”. At the moment all the farmers are using uncoverd tanks leaving the gas to environment. They are unaware of the effect of greenhouse gases.

Covering the tank has lot of issues in operation the tank. Still exploring the options.

If any body has any ideas please suggest.Crazy ideas are most welcome(I give seriouse attention  to crazy ideas. Many crazy ideas have worked out me very well when I tune it for my requirement)

Dear Peers & Colleagues,

It is high time MOO-ve-OVER WIND AND SOLAR Energy - COW DUNG IS HERE.

Cow dung gas is 55-65% methane, 30 - 35% Co2 with some hydrogen, nitrogen and other traces. Its heating value is around 600 BTU per cubic foot.

Natural gas consists of around 80% methane yielding BTU value of about 1000.

Bio-gas may be improved by filtering it through lime water to remove co2, iron fillings to absorb corrosive hydrogen sulphide and calcium chloride to extract water vapor after the other two process.

cow dung slurry is composed of 1.8 - 2.4% nitrogen  (N2) , 1 - 1.2% p2o5 , 06 - 08 % k20 and 50 - 75 % organic humus.

about 1 cubic foot of gas may be generated from 1 pound of cow manure at 28c. this is enough gas to cook a days meal for 4-6 people in India.

about 1-7 cubic meters of bio-gas equals 1 litre of petrol. The manure produced by 1 cow in 1 year can be converted to methane which is equivalent of over 225lts of petrol/gasoline.

now the question - is it possible ?

need your inputs


Hai Sri,
Methane gas can be used for your cooking pupose.

Hi Prasath,

Its very simple all you need is dug a pit on higher ground and dump your cow dung on top of it 4 inches on garden soil or farm soil. No watering.
Better use your cow dung for bio gas and use the slurry as such for your fields without composting.

I agree with you. The challenge is, it needs a dome to collect. If we cover our bio digester we cannot refill bio mass, we use all agri waste, weeds, poultry manure, dung etc. so the filling will be dry matter and solids.

What you suggested is easily achievable in anaerobic biodigester where only dung slurry is feed from a separate chamber.

We dont have dome on this tank. It is difficult to operate if we have a dome.

Hi Sri,
If you can send me the photo of your biodigester and showing how to feed the biodigester the idea can be given. No problem. One question does the bio digester needs to be in open condition.


I am still designing my own digester. I have visited few farms who already has. If you see above post there is a youtube link. it is exactly looks like this.
I am taking a environmental engineers to calculate retention time, cubic capacity etc… But I will surely post pictures when I succeed. I will also post calculation details.

Yes. It needs to be open to fill biomass.

Just see this if it is ok. The dome will lock itself due to gas and comes down when there is none. ???

I got the idea. I will discuss this with my engineer.

Thank you sir.

I need the design and layout of the tanks and also the construction details. Also I would like to know  the operation technique of the digester tank. where can I get the info? I have seen the video but can understand little as I dont know Kannada.

thanks and regards
K Parthasarthi

All are right at their points if one cane understand them independently.
There are many ways to utilize Cattle produces to enhance soil fertility and other essential products like manure, energy, light etc for human comfort.

  1. Make manure in conventional method.
  2. Make Jeevamrutha varieties.
  3. Do vermi copost.
  4. Do Bio digester.
  5. Do Jeevasaara.
  6. Do amrit Jal
  7. Do Panchagavya & even more.
    Cattle products like Cow Dung & Cow Urine along with other agri wastes are basic ingredients for all processes mentioned above. Decide the simple way of preparing compost for your requirement.

Think which is easy for you to adopt.

Mr. Swamy,

Composting or using the cow urine and cow dung in agriculture is easy but what we are discussing is using how to avoid global warming by stopping green house gas to escape.

Subject matter is differing from what you mentioning.
I mentioned the processes of Compost Preparation.

However what you can do with H2SO3 (which can arrest human cardiac system within 30 to 40 seconds) produced in the process bio digester which you mentioned?