Texas Wastewater Class B Practice Exam - Prep Guide & Practice Questions

The typical percentage of methane found in digester gas is most commonly in the range of 50-70%. While some sources might indicate higher ranges, the majority of digester gas produced in wastewater treatment is approximately 65-75% methane. This range reflects the efficiency of the anaerobic digestion process, where organic matter breaks down and converts into biogas, predominantly made up of methane and carbon dioxide, among other gases.

The other choices reflect either lower or higher percentages that do not align with the standard measurements for digester gas composition. Understanding the correct methane percentages is crucial, especially for operators in wastewater treatment, as it significantly impacts energy recovery and operational efficiency.