Biogaasitöötlus

Biogaasitöötlus, also known as biogas upgrading or biogas purification, is the process of removing impurities from raw biogas to produce a higher quality gas, often referred to as biomethane or renewable natural gas. Raw biogas is typically produced from the anaerobic digestion of organic matter, such as agricultural waste, sewage sludge, and food waste. It is primarily composed of methane (CH4) and carbon dioxide (CO2), with smaller amounts of other gases like hydrogen sulfide (H2S), water vapor, and nitrogen.

The primary goal of biogaasitöötlus is to increase the methane content and remove undesirable components. This is crucial for several applications. For instance, to inject biomethane into the natural gas grid, it must meet strict quality standards, which typically require a methane content of over 95% and very low levels of CO2, H2S, and water. Biogas upgrading also makes it suitable for use in internal combustion engines for electricity and heat generation or as a vehicle fuel.

Common biogaasitöötlus technologies include water scrubbing, pressure swing adsorption (PSA), membrane separation, and chemical scrubbing. Water scrubbing uses water to absorb CO2, while PSA uses adsorbent materials to selectively remove CO2 and other impurities. Membrane separation utilizes semi-permeable membranes that allow methane to pass through more readily than CO2. Chemical scrubbing involves using chemical solvents to capture CO2. The choice of technology depends on factors such as the composition of the raw biogas, desired product quality, and economic considerations.

The purified biogas, or biomethane, is a versatile renewable energy source that can significantly reduce greenhouse gas emissions compared to fossil fuels. It offers a sustainable alternative for heating, power generation, and transportation, contributing to a circular economy and decarbonization efforts.