Florida Wastewater Practice Test

To measure the load being applied from the digester to the head works, what test would you perform?

1. Biochemical oxygen demand test

2. Sludge volume index test

3. Total solids test

4. Chemical oxygen demand test

The correct answer is: Total solids test

The total solids test is the appropriate choice for measuring the load being applied from the digester to the headworks. This test quantifies the amount of solid material present in a liquid sample. By analyzing the total solids, which includes both suspended solids and dissolved solids, operators can determine the concentration of solids being transported from the digester. This measurement is crucial in understanding the efficiency of the digester and the subsequent treatment processes at the plant. In the context of wastewater treatment, knowing the total solids helps in calculating the necessary adjustments in processes like precipitation, filtration, or biological treatment, ultimately ensuring effective treatment of the water before discharge or reuse. While tests like biochemical oxygen demand and chemical oxygen demand are essential for understanding the organic load and overall water quality, they do not directly measure the mass of solids in the effluent. The sludge volume index, on the other hand, is primarily used to evaluate the settling characteristics of biomass in a wastewater treatment system, and, while relevant in its own right, it does not provide the information needed to measure the solid load directly leaving the digester.