What is the expected reduction in volatile solids by a well-operated digester?

A well-operated digester is designed to reduce volatile solids effectively during the anaerobic digestion process. The typical expected reduction in volatile solids in an efficient digester ranges between 25% to 30%. This range indicates a significant breakdown of organic materials, resulting in higher biogas production while also reducing the mass of the remaining solids.

The process within a digester involves microorganisms that decompose organic matter in an oxygen-free environment, which not only stabilizes the waste but also generates usable energy in the form of biogas. The effectiveness of this process is reliant on several factors, including the types of feedstock, retention time, temperature, and mixing capabilities within the digester.

A reduction level falling within the ranges of 15-20% or lower is typically indicative of either suboptimal operating conditions or limited feedstock decomposition, which would not be considered reflective of a well-operated system. Hence, the choice of 25-30% accurately reflects the operational efficiency and goals of anaerobic digesters in reducing volatile solids in wastewater treatment processes.