maybe you can try to isolate methanobacterium from lake/river sediment or other anaerobic environments. good luck! 

it would be interesting for agricultural lab scale biogas reactors ....

I'm wondering why you don't have access to animal manure. It's basically everywhere and you can use slurry or diluted manure. If still struggle with animal by-products try to find sludge from wastewater treatment plant. They normaly provide it without problems. 

Thank you for the assistance, decide to go with anaerobic sediment from the nearby river.

I do second what Pavel just said, even if the animal manure is dry the methanogens will still be viable.

Alternatively you can also you samples from composting pits, drawing samples from the core of the compost would yield better results.

Just bear in mind the bacteria from sediments are quite different. They are psychrophilic, live in high pressure and normally deal with different “feed”. For this reason, it may take them more time to get used to your feed and new living conditions. I would still use manure-based bacteria.

Prefer to seed the digester using animal manure. Dry or wet (slurry) does not matter so much. If you cannot find it, use sewage or primary sludge.  

Effluent from existing AD facility will be the best inoculum. In addition to sediment, you can use sewage sludge.  Rumin fluid is also a good inoculum, but I assume you cannot get it as you even don't have access to manure. Soil also contains anaerobes. Finally, you can try to grow your only methanogens by anaerobically incubate your kitch garbage, with small amount of whatever feces you can find.  

Be patient.  It takes some time to develop an active inoculum in the digester.  Avoid oxidizing agents in the influent that can inhibit or kill anaerobes.  De-chlorinate any water being used to fill the AD.

Thank you very much for  all the feedback.

Molasses distillery waste known as stillage

Humphrey

Yes.. any kind of anaerobic sludge from large scale digestor treatming MSW, WWTP sludge.. will rapidly adapt to livestock manure

Try the rumen from a slaughter house... it is loaded with methanogens but also a large number of complimentary microbes that accelerate the process.

Try mud from pond

I am interested in the mud from pond solution. Can anyone confirm its suitability as innoculum?

i have found a 500 gm/1m3 inoculate. easy to install and great. however i am yet to confirm the model which will be ready in a month time. no dung required. only a 500 gm packetof my innoculum is enough for 1000 ltr biogas digester ! (if all goes right)

Dear Santhosh, Any updates.

Biological Septic System additives can be used. Not sure what is available in SA, but in the US, there are multiple brands, which, when combined, can be used.

Not as robust as those from multiple manures (Horse, Cattle and Swine manures, mixed, would be far better.)

IF, however, you CAN source the manures, a series of 4 of the 1,000 liter IBC tanks can be used to produce biologically active effluent, starting with manure and water in the first, with a fairly straight inoculant as a final output. Fill the first with ~5-% manure mix and top with water. As you feed the first, displacing through the subsequent tanks, use the displaced water from the last, to mix the influent for the first, until you get a calculated 4,000 liters throughput.

NOTE: You will be producing Biogas during this process. Methane is up to 30X worse greenhouse gas than CO2, before it breaks down into CO2 and water. Please capture and burn all of the Biogas produced, to release only CO2 and water vapor.

I am in the process of building a system based on this, to provide active inoculant for Anaerobic Digesters, here in the US. As a bonus, bubbling the gas from tank #1 through #2, then all the gas from #2 through #3, and #3 through #4 should upgrade the Biogas to near Natural Gas purity, because the Archaea will begin utilizing the CO2 as an ion source, once the H2 has been used.

Use a setup similar to the one found here:

http://www.solarcities.eu/education/388