Thermal mass flow meters unlike that of alternate flow meters do offer precise and reliable biogas measurement. They also provide numerous unique benefits. Gas moisture contents present in the biogas applications do require to be considered.
According to the experts, biogas is actually a form of gas which can be found naturally. It takes places with different types of organic materials decomposing. It is a mixture of methane as well as carbon dioxide, besides various other gases, but in small amounts, like hydrogen sulfide, nitrogen including other gas elements, however, in traces. Composition of gas however, is likely to differ with methane being 35%, carbon dioxide being 65% and methane to 70% and carbon dioxide to 30%. But biogas is found to be dirty and moist. The sources from where it is availed are digesters from energy to waste plants, waste-water treatment plants to landfill operations.
About wastewater treatment plants
This source offers incoming sewage that consists of organic solids. The latter is separated at a later stage from liquid. The available sludge undergoes numerous treatment procedures to include anaerobic digestion. There are much larger wastewater treatment plants that make use of common anaerobic digesters. Some microorganisms in anaerobic digesters tend to decompose because of lack of oxygen. Thus biogas is produced, with sludge amount getting reduced. The digester based biogas composition will be 60-65 percent methane and 35-40 percent carbon dioxide. Then biogas is burnt in the engine, thereby producing volume of biogas, sufficient to meet increasing demands of energy from plants.
Facilities that convert organic materials to biogas are referred to by this name. Organic materials that are used can be livestock manure, agricultural waste products such as food byproducts and vegetable processing. Big covered lagoon is often used rather than separate digester vessel.
LFG (Landfill Gas)
Organic material that gets decomposed from municipal solid waste is what produces landfill gas. The organic materials that are used are often food scraps, waste papers and cardboard. Several collection manifolds along with extraction form the collection system and connect to the major manifold combined with the blower. Numerous options also exist to do away with LFG. However, there are chances of LFG getting flared up even by a tiny landfill present in the property. The bigger landfill operations may feed landfill gas to boiler or engine, thereby producing energy. In some cases, it becomes possible to treat LFG and natural gas pipeline. It is after 5 to 7 years that optimum LFG flow tends to occur, but only after it begins to decline. With the landfill’s life, the ratio of methane to carbon dioxide also changes.
It can be really challenging to measure flow rate of biogas accurately and correctly. However, this entirely depends on source of biogas obtained. Also is to be considered application specific issues when thermal mass flow meters are used. Several benefits can be enjoyed by using thermal mass flow meters. Some of the benefits that thermal mass flow meters have on offer when measuring biogas are given below:
• Digester gas mostly dirty, thereby requiring proper flow meter maintenance. Thermal mass flow meter may include retraction equipment, thus permitting probe elimination to allow cleaning from time to time basis.
• Pressure correction and temperature may not be necessary with mass flow measurement.
• Digester gas flow may be of low velocities. Proper low velocity sensitivity may be availed by thermal mass flow meter.
What is to be considered?
Digester gas may comprise condensed moisture and hence, wet. Spiking may be caused by the latter in thermal mass flow meter. At times, condensed moisture could be removed successfully. This is done with the help of moisture drop out chamber. This vessel does offer velocity reduction including direction change, causing moisture droplet separation from gas stream.
In short, thermal mass flow meter can help to offer accurate and reliable bio gas flow meter. Also, several advantages can be derived from this tool unlike that of other alternate measurement technologies available in the market.
For more information on biogas flow meter, check sites such as https://www.silverinstruments.com/ and take correct decision. Having good knowledge about the same can help ensure taking the correct decision!