Question

Name two sources of biogas

Answer 1

Renewable Energy Sources | Biogas | Sources of biogas

Biogas can be obtained from disparate starting materials with slight differences in the preparation and production. The basic prerequisites to any waste material could be used economically as a raw material for the production of biogas are:

to be available in sufficient quantities throughout the year

in composition to the efficient and economical production of biogas
if it did not have toxic substances.
We distinguish several types of biogas from raw materials for its production: landfill biogas biogas from agriculture production, biogas from wood waste and biogas waste water from industry and cities.
         Landfill gas
In industrialized countries it is produced 300-400 kg of waste per person per year. This garbage is collected and disposed of in safe sanitary landfills, which include the protection of ground water and air protection from dirty and dangerous landfill gas, by putting the cover over the storage of waste. The aforementioned landfill gas is generated by decomposition of organic matter under the influence of micro-organisms under anaerobic conditions. At the heart of waste generated overpressure, and landfill gas passes into the environment. The average composition of landfill gas is 35-60% methane, 37-50% carbon dioxide and small amounts are found carbon monoxide, nitrogen, hydrogen sulfide, fluoride, chlorine, aromatic hydrocarbons, and other trace gases.
Based on this composition of landfill gas, it can be seen that it is very dangerous for the environment, for the health of living organisms, and the infrastructure facilities in the vicinity of landfills, because the methane in certain conditions is very explosive. Methane is over 20 times more harmful to the climate and the ozone layer than carbon dioxide, which means that 1 tonne of methane ozone depleting refrigerants (greenhouse effect) as 21 tons of carbon dioxide. The average time of reaction for methane with ozone is on the order of 25 years and the carbon dioxide reaches the order of 80 years, which also greatly affects the methane is approximately 21 times more harmful to the ozone layer than CO2, and primarily the reason, you need 3 ozone molecule O3 to turn methane into carbon dioxide CO2.
In order to remove the negative effects of uncontrolled proliferation of landfill gas, collection is carried out planned and forcibly directing gas to the place of burning. This process favors the rapid stabilization of the fresh parts of the landfill, reducing the pollution of wastewater. Landfill gas can use energy in processes of heating, hot water, or electricity production.

Answer 2

Gaseous waste is mostly generated by human activity. The gaseous wastes include carbon dioxide (CO2), methane (CH4), chlorofluorocarbon (CFC), oxides of nitrogen (NOx), carbon monoxide (CO) etc.