Welcome back to TPO magazine's Exam Study Guide Series, which offers a pair of water/wastewater study questions with in-depth explanations of the answers. Last time, we covered a set of wastewater and drinking water treatment questions on the topics of Solids Retention Time and Total Trihalomethanes. This time you can test your knowledge about anaerobic digester classifications and water hardness calculations.
Wastewater Treatment Sample QuestionWhich classification of anaerobic digester is the most efficient at pathogen reduction, increased volatile solids reduction and decreased detention times?
A. Heterophilic B. MesophilicC. ThermophilicD. ATAD
Water Treatment Sample Question
Using the data below, what is the approximate magnesium concentration in mg/L?
Total hardness = 470 mg/L as CaCO3
Calcium = 136 mg/L
Elements and
