Guide to Cow-powered Biogas Energy Released

I hope that report includes cautions! Methane is odorless, colorless, explosive, and very deadly. We had some people die in a digester accident here in California while cleaning out a pit where they suffocated. It's a good use of farm waste, but it requires careful preparation and operation.

Methane is also the main component of natural gas(over 90%).

If we convert coal fired powerplants and applications to natural gas---there will be far fewer pollutants emitted into the atmosphere, no environmental damage from strip mines, no ash and creasote to have to dispose of and have problems of leaching toxins, and very negligeable water table and watershed damage compared to coal mining.

As more biomethane becomes available---it can be mixed with natural gas in any proportion with no loss of performance or need to change or modify any application equipment. Biomethane and fossil fuel methane are identical chemically---the only difference is where the methane came from.

As a developer of small bio-gas digesters that use either cow manure and Ag. Waste; or municipal ones which integrate organic solid waste with liquid waste---Read Bio-Cycle this month on why Toronto switched from composting to anaerobic digesters; bio gas generators for farmsteads are on the way in.

Gas scrubbing is an emerging technology that has attracted a global vendor base.

Methane is approx. 60% of the gases emerging from a digester and also contains CO2, NO, O, and traces of hydrogen sulphide and ammonia.

CO2 is removed with expensive commercial devices like QuestAIR's, or simply bubbling through water. When removed as a gas it can be used to flood greenhouses, i.e. sold.

NO can be fixed using bio-filters as a growing medium for bacteria.

Hydrogen sulphide is both smelly, and highly corrosive.

The inexpensive way is to include iron in the bubbler, i.e. steel wool which reacts with the sulphides; another is to use microbes which convert the sulphides to a capturable form of sulphur...see Placques(developed by Shell)

Water is precipitated out by cooling the emerging gas in a water trap.

When done you get 'pipeline' quality natural bio-gas that can be blended with conventional natural gas, or compressed to use in CNG vehicles, or burned for heat---if it's only heat, typically the gas is piped to a boiler or a stove for cooking.

JENNBACHER and CAPSTONE generators will burn the gas for electricity, and there are new fuel cells which also run on clean natural gas.

Unlike hydrogen, a really dangerous and explosive gas, we've had almost 2 centuries of using natural gas as an energy source.

Hydrogen Sulphide at a level of less than 1,000 ppm is ok for turbines; however the emergence of siloxanes--a silica based ingredient in shampoos, etc. as a major problem----silica is formed which coats internal components of a turbine or engine. is just another engineering problem to solve.