As part of an integrated waste management system, anaerobic digestion can also reduce the emission of landfill gas into the atmosphere. Anaerobic digestion is a renewable energy source because the process produces a methane and carbon dioxide rich biogas suitable for energy production helping replace fossil fuels. Also, the nutrient-rich solids left after digestion can be used as fertiliser.

Scientific interest in the gasses produced by the natural decomposition of organic matter goes back a long way. Biogas was first reported in the seventeenth century by Robert Boyle and Stephen Hale, who noted that flammable gas was released by disturbing the sediment of streams and lakes. In 1808, Sir Humphry Davy determined that methane was present in the gasses produced by cattle manure.

It has been reported on the web that the first anaerobic digester was built by a leper colony in Bombay, India in 1859. In 1895 the technology was developed in Exeter, England, where a septic tank was used to generate gas for street lighting. Also, web sources report that in England, in 1904, the first dual purpose tank for both sedimentation and sludge treatment was installed in Hampton. In 1907, in Germany, a patent was issued for the Imhoff tank, an early form of digester.

The biogas digester (anaerobic digestion plant -AD plant ) also, of course, has a big part to play in farming. An AD plant captures naturally occurring gas from manure and converts it into electricity. One recently publisher US News item declares that with their new AD system, they are generating up to 300,000 kilowatt-hours per year fo their farm. That is an value in power of about $40,000 a year!

The farming industry is developing a variety of AD Plant systems using differnet technologies. Placing a tarpaulin over manure ponds can provide a very basic biogas digester. Doing it eliminates the release of methane (a natural byproduct of manure) into the air. The amount that can be removed is small in overall emissions terms but could be significant. According to the 2003 U.S. Department of Energy Report on Greenhouse Gases, agricultural sources, primarily animal waste, account for approximately three percent of greenhouse gas emissions. The same source reports that a dairy cow can generate 120 lbs. of waste each day, totaling about 40,000 lbs. per year. Furthermore, using a digester wastes nothing as the solids separated from the waste are composted and reused as fertilizer, providing additional, and highly sustainable benefits.

The Original Post is Located Here: Biogas Digester Development And Increasing Adoption

Biogas is a mixture of about 60-70% methane (natural gas), 30-40% carbon dioxide and other trace gases, such as hydrogen sulfide. The heat content of this gas is based on the amount of methane it contains and is about 600 BTUs per cubic foot.

Anaerobic digesters produce biomethane along with electricity generation and saleable end product biosolids which allows animal production enterprises to become neighborhood and environment friendly, as well as producing another revenue flow for themselves.

Running a biogas plant on a dairy farm works best for farms which hold at least 800 cows. Economically viable ystems for dairies under 800 cow level are possible, but need evaluation on a farm by farm basis to decide whther there will be adequate cost effectiveness. No farm or combinations of farms is ever likely to be too large for such a system.

Whether a particular farm, your farm perhaps, would be suitable for a biogas plant depends on assessing the budget costs of the investment, against the potential earnings from generated electricity sales and from end product bio-solid sales. The economic return period for any farm can be estimated this way. If the return period is short enough and an investor can be found there is a lot to be said for going ahead.

Many people will ask you to demonstrate that the new plant does not have a negative impact on the surrounding environment. Let us assure you that a well designed and run biogas plant improves the environment significantly and is neither odorous nor dangerous. Such plants can be placed near production facilities which will often be the best customers for the power and heat produced.

Equipment is fitted to the digester plants to suit climate conditions. The bioreactors have thermal insulation and are heated by heating and also have a cooling system for summer use. In cold winters a biogas plant can consume up to 50% of its produced heat power.

The liquid that results from the anaerobic digestion process has solids which are separated out, composted, and sold to local gardeners, landscapers and farmers. Some farmers use the solids as bedding for their cows and sell it as bedding to neighbors. The liquids are returned to the farmer as nutrient rich natural fertilizer, which replaces imported nutrients and thereby cuts costs.

There is an issue, and it is a fallacy, going around that Anaerobic Diesters always smell. We would contest this. Anaerobic digesters actually tend to alleviate odor problems when on a well run, especially as suburban growth surrounds farms and introduces neighbors who complain about manure smells most often due to nearby farming activities and not the AD plant at all.

By installing an anaerobic digester, the conscientious farmer can actually solve odor issues to everyone’s satisfaction. Since the digesters are airtight, the smell stays within, and the liquids and solids coming out of the digester have only a very slight odor compared to the raw slurry.

The Original Post is Located Here: Biogas And Issues Which Arise In Its Production