Tennessee Wastewater Operator Practice Exam

What is the fate of inorganic solids entering the digester?

1. They are converted into volatile solids

2. They are eliminated from the digester

3. They pass through the digester unchanged

4. They are transformed into organic solids

The correct answer is: They pass through the digester unchanged

In the context of a wastewater treatment process, inorganic solids that enter the digester primarily consist of materials like sand, silt, and other non-organic particles. Digestion is a biological process where microorganisms break down organic matter, but inorganic solids do not undergo biochemical transformation in the same way. As a result, these inorganic solids generally pass through the digester unchanged. They do not get metabolized or converted into other forms since they lack the biological components necessary for decomposition by microbes. Instead, they are typically retained within the system until they are eventually removed during routine maintenance or sludge management practices, but their fundamental composition remains unaltered throughout the digestion process. The other answers imply different fates for these solids, such as conversion or elimination, which do not accurately reflect the behavior of inorganic materials in a digester. Understanding this concept is crucial for managing solids in a wastewater treatment facility.