Design of primary settling tank for domestic wastewater treatment

Treatment of domestic wastewater is necessary to reduce the pollutants in it to a level nature can handle otherwise environment and human health can be significantly impacted. Domestic wastewater treatment is used to remove the contaminants and convert it into an effluent that can be returned to water cycle. Wastewater treatment includes pre-treatment, primary treatment, secondary treatment, disinfection and effluent release to obtain water of desired quality. A part of primary treatment is primary clarifier which plays a crucial role in the removal of suspended solids from domestic wastewater under the influence of gravity which produces less turbid effluent for further processing. The design parameters of the clarifier include overflow velocity, settling velocity, detention period, dimensions of tank, efficiency.