How to generate Biogas from Wastewater Treatment Plant?
Physical, chemical, and biological pollutants are present in wastewater generated by households, industries, agricultural activities, and commercial institutions.
Every year, millions of tonnes of organic waste, including livestock manure, agricultural waste, fats, oils, and food waste, reach wastewater treatment plants. On the other hand, it contains toxic chemicals and pathogens that, if not properly managed, can have a significant impact on water resources and human health. As a result, biological wastewater treatment is critical.
Mechanical/biological treatment is the most widely used method of municipal wastewater treatment around the world.
Modern sewage treatment plants demonstrate highly efficient wastewater treatment with almost no impurities. Sewage sludge is formed as a byproduct of purification, allowing it to be used as a source of energy and biomass in the future. Sewage sludge, on the other hand, may be used only after proper treatment, which reduces or removes the high water content load, extraneous contamination, pathogenic bacteria, and malodorous substances.
Microorganisms act on waste in the biological wastewater treatment process, causing it to decompose. Depending on the presence of oxygen, microbes perform waste degradation in one of two ways: aerobic or anaerobic.
Microbes decompose organic waste in wastewater treatment plants in the absence of oxygen during the anaerobic process. The end result is a mixture of methane and carbon dioxide. One of the benefits of anaerobic waste digestion is the production of biogas.
Biogas has a number of advantages
It generates heat and energy, which can be used to power the wastewater treatment plant as well as other applications such as running engines, microturbines, and fuel cells. When converted to bio-methane, it can be used as a vehicle fuel.
There is a belief that biogas is a dependable source for meeting the demand for clean and renewable energy, thereby halting climate change and preserving the environment in the future. Furthermore, biogas generation provides wastewater treatment plant managers with an opportunity to save money on waste remediation.
Solutions that promote sustainable biogas production from wastewater treatment plants are desperately needed. As a result, a better understanding of the anaerobic digestion process, its fundamental principles, and related factors is required.
Biogas Production and Anaerobic Digestion
Microorganisms play an important role in the anaerobic digestion process by decomposing organic waste and using the energy released for growth. This process occurs in a treatment plant's digester tank and is divided into four stages: hydrolysis, acidogenesis, acetogenesis, and methanogenesis.
In each of these four phases, different microbes are used. Non-soluble biopolymers are converted to soluble organic compounds in the first phase. Acidogenic bacteria act on the soluble organic compounds in the second phase, converting them to volatile fatty acids and carbon dioxide. In the third phase, it is converted to acetate and H2. Methane is produced in the final stage.
Temperature, pH, alkalinity, and toxicity are all factors that influence all phases of the anaerobic digestion process. At the same time, when microbial activity is at its peak, the best plant process is possible.
Furthermore, the loading rate of anaerobic reactors is determined by microbe processing capacity. The reactor should contain a sufficient number of microbes. Furthermore, regular contact between feedstock and bacterial mass is important.
As a result, anaerobic wastewater treatment plants aid in the development of biogas. However, there are several challenges that must overcome in order to achieve sustainable production. It includes treatment facilities that are malfunctioning or underperforming, as well as low productivity through a biological process.