WASTEWATER TREATMENT EXAM QUESTIONS WITH LATEST UPDATE

Unit operations - Answer-methods of treatment in which the application of physical forces predominates. [Preliminary and primary treatments] Unit processes - Answer-methods of treatment in which the removal of contaminants is brought about by chemical or biological reactions. [Secondary treatments] Primary Treatment - Answer-Physical operations are used to remove the floating and settleable solids Secondary Treatment - Answer-Biological and chemical processes are used to remove most of the organic matter. Tertiary and/or Advanced Treatment - Answer-Additional combinations of unit operations and processes are used to remove other constituents, (N and P) that are not reduced significantly by secondary treatment. Natural Systems - Answer-"Land treatment" and/or "wetlands" combining physical, chemical and biological treatment mechanisms Natural Systems do not treat water the same quality as advanced wastewater treatment. True or False - Answer-False Can produce water with quality similar to or better than that from advanced wastewater treatment. Combined Sewers - Answer-• One pipe collects domestic wastewater, stormwater, light commercial and industrial wastewaters, etc. • Usually only dry weather flow (domestic, street drainage and commercial/industrial wastewaters) is intercepted for treatment. Combined Sewer Overflow (CSO) - Answer-During major storm events, combined volumes may exceed the capacity of the treatment plant, requiring bypass directly to the receiving water Unit operations of pre-treatment - Answer-• Several devices are placed upstream of the primary treatment to provide protection of the WWTP equipment; ensure proper operations of downstream processes.