Environmental Protection

Biogas and Environmental Protection

Biogas can be used as a fuel that can displace the use of fossil fuels. However, biogas is methane rich, having up to more than 50% methane by volume. As methane is much more effective than carbon dioxide as a greenhouse gas, it is important that untreated emissions of methane to the atmosphere are minimised. The most effective way is to use the qualities that make biogas a useful fuel. However, failing this, flaring of the gas is essential to ensure complete environmental protection.

Operation and Maintenance

O&M of Biogas Fuelled Plants 

Key to the success of any biogas project is the operation and maintenance of all components of the system. Our technical operators are all highly qualified and motivated to ensure that all aspects of the operation functions smoothly and efficient ensuring maximum uptime and optimum environmental protection. Our aim is to contribute a clean environment by caring for our natural resources.

Biogas from Anaerobic Digestion

AD of Organic Material

Many industrial processes result in the production of wastewater which, if not treated correctly, can pose a significant threat to the environment. The production of tapioca uses a lot of water during the process and this must be treated prior to release back to the environment. If the wastewater is collected in a covered lagoon and the biogas is collected, it can be used for powering the process. Another example of a waste material being converted into a resource.

Biogas as an Alternative Fuel

Fuel from Biogas

Biogas is produced from landfill sites that have been the repository for organic rich waste material such as Municipal Solid Waste. When a landfill is subjected to anaerobic conditions, organic material degrades biogas is one of the main products. Methane, a highly contaminating greenhouse gas, is one of the principal elements of landfill biogas and has often caused signifcant environmental concern. Technology exists to convert this into a valuable energy resource not only reducing the direct environmental effects but ensuring commercial viability.

Biogas Treatment and Cleanup

The Treatment and Cleanup of Biogas

The generation of biogas is not a simple clean process and many elements, that can be harmful to engines and other equipment, can be entrained in the gas stream. Hydrogen Sulfide is a particularly difficult element with which to deal and it requires careful handling to ensure that not only is it minimsed in the gas stream but that it is also safely disposed of. Organics fabricates and supplies biological H2S control units that have been successfully employed on biogas projects around the world.

Monitoring and Adjustment of Emissions

Biogas Emissions

The production of emissions from an energy generation plant that uses biogas must be strictly controlled to ensure that no unwanted elements are entrained, either in the gas stream or in the exhaust gas emitted to atmosphere. On most plant that use biogas as a fuel, or that simply control methane emissions to atmosphere, the site license dictates that emissions must meet stringent standards. Monitoring of these emissions is critical in compliance to ensure both environmental protection and continuing commercial viability.

The Importance of Cleanliness

Cleaning up After Ourselves

For well-publicised reasons, the production of palm oil is a process that causes much public consternation. But palm oil is popular not only because of its versatility but also because it creates local employment. It is used in literally hundreds of products and is an important ingredient of many that are critical to modern-day living. Palm-oil production companies are now conscious that consumers do not tolerate environmental destruction without compensation. Using the biogas generated by the wastewater not only ensures that the environment is protected from polluting emissions but that the use of fossil fuel in energy production is reduced.

The methane molecule is composed of four hydrogen and one carbon atom. At room temperature and standard pressure, methane is colorless and odorless. It is a highly toxic greenhous gas being some 21 times more effective then carbon dioxide at capturing heat in our planet’s atmosphere.

Composition

Biogas is composed of a cocktail of elements, the principal ones of which are methane, carbon dioxide and nitrogen. Methane is a compound of carbon and hydrogen with the formula CH4 and, by itself, has no distinctive odour. It is a highly effective greenhouse gas being some 21 times more effective than CO2.

Environmental Impact of Biogas

Biogas is generated by the reactions of biodegradation of organic matter. It is formed under anaerobic conditions in the absence of oxygen and is commonly known as marsh gas.

Depending on the substrate from which it is produced, biogas can also contain other contaminating gases such as hydrogen sulfide. In landfill sites, biogas is produced from degrading organic waste material and, apart from the unpleasant smell, can cause serious problems if not adequately controlled.

But methane is also used as a fuel. If it is treated and cleaned, biogas can also be used for a fuel that can displace traditional fossil fuels as a source of energy for power or heat production.

Biogas Production

Biogas may be produced from many different biodegradable organic substrates.In general, however, its composition will be very similar, being comprised mostly of CH4, at between 40% and 65% by volume, CO2, at between 30% and 40% by volume, and a number of trace gases.

The feedstock dictates the biogas technology to be used. In order to properly design a biogas plant, the developer must fully understand its feedstock and its conditions of production. Once understood, the biogas feed train can be designed to tailor the needs of the site and purpose of production.

In any project that uses biogas as its principal source of fuel, it is important to undertake a comprehensive analysis of all conditions including the substrate from which the biogas is produced and whether or not specialist technology, such as H2S removal equipment, must be employed in cleaning and filtration.

Uses of biogas can range from power and heat generation to the production of a natural gas for injection into regional pipelines or for compression as a vehicle fuel.

Technologies Employed

Biogas can be produced in digesters. Production depends on the following factors:

Organic content
Wet or dry waste
Land availability

There are several different types of digester technology including lagoons which are typically employed when the feedstock is wastewater effluent from agricultural wastewater or animal manure. Using this technology, typical retention time of material is between 30 and 40 days for the biogas to reach full production. A lagoon is a good option when sufficient land is available.

Other technologies such as Continuously Stirred Tank Reactors (CSTR) and Dry Cell Anaerobic Digestion (DCAD) are used when land requirements are limited. CSTR’s are a proven and reliable technology as an alternative to a lagoon based system but are slightly more expensive to build than a lagoon, and require more attention during operation.

 

Biogas Conditioning Options

To use biogas in any industrial process, it is important that the gas is filtered, or conditioned, prior to use. Technologies employed may include H2S or CO2 removal. H2S is a highly corrosive trace element of biogas and can be present in elevated concentrations if the biogas is produced from agricultural waste or extracted from landfills where there is a high content of gypsum.

CO2 must be removed from the biogas stream if the gas is being used for the production of a natural gas substitute or for the production of compressed gas for use as a vehicle fuel.

Power Production Options

Biogas can be used in a variety of ways for the production of energy. Not only can it be used directly as a fuel for power generation once it has been conditioned and cleaned, it can also be used for the production of steam for use in steam turbine engines or directly as heat production. On many landfill sites, biogas is used for the evaporation of leachate or for providing heating for on-site offices.

One of the technologies that has recently been gaining traction is the use of biogas as an alternative fuel for vehicles, mainly fleet vehicles such as buses or lorries. As the technology has now been developed to clean biogas to natural gas specification, it can now be fed directly into natural gas pipelines.

ORGANICS GROUP

Please consult the following pages before using our site:

Organics Privacy Policy

Data Privacy and Protection Policy

CONTACT

Please contact us for further information

SOCIAL MEDIA