What is the function of a biodigester?

A biodigester is a system that processes organic waste materials through anaerobic digestion, which is a biological decomposition process carried out by microorganisms in an oxygen-free environment. The primary function of a biodigester is to convert organic material, such as agricultural waste, food scraps, and animal manure, into biogas. This biogas primarily consists of methane, carbon dioxide, and smaller amounts of hydrogen sulfide, along with other fuel gases.

Option C highlights the production of gases like carbon dioxide and hydrogen sulfide, as well as other fuel gases, which are significant outputs of the anaerobic digestion process. The methane produced can be used as a renewable energy source for heating, electricity, or as a vehicle fuel, making biodigesters valuable for both waste management and energy production.

In contrast, the other options reference processes and functions that are not typical of a biodigester. For example, the production of electricity from solar energy pertains to photovoltaic systems, not biodigesters. Similarly, producing fertilizer from industrial waste could describe other processing methods such as composting or chemical treatments but does not emphasize the gas production characteristic of biodigesters. Finally, cleaning up water pollution typically involves treatment plants or filtration systems rather than the biological processes of a biodig