July 5, 2016

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Zita Yu Publishes Graywater Treatment Paper for Journal - American Water Works Association 

Zita Yu (California) has expanded Geosyntec's graywater practice capability in an article where she and her co-authors consider the performance and economic feasibility of residential bathroom graywater treatment.

The research results were recently published in a paper entitled "Performance and Economic Evaluation of a Semibatch Vertical-Flow Wetland for Onsite Residential Bathroom Graywater Treatment." The paper was published in Journal - American Water Works Association, Volume 107, Number 7, July Issue 2016.

Journal is published by the American Water Works Association (AWWA), established in 1881, and is the largest nonprofit, scientific and educational association dedicated to managing and treating water. With approximately 50,000 members, AWWA aims to provide solutions that improve public health, protect the environment, strengthen the economy and enhance our quality of life.

Abstract

The performance and economic feasibility of residential bathroom graywater treatment using a semibatch vertical-flow wetland was evaluated over an eight-month field study in a single-family home in Los Angeles, Calif. Graywater treatment time of only 3 h produced an effluent with turbidity (~0.3 ntu) and 5-day biochemical oxygen demand (~3.1 mg/L) that met graywater reuse guidelines for nonpotable applications. After chlorine disinfection, total coliform count was below the mandated level of 2.2 most probable number per 100 mL for aboveground water reuse. Process modeling demonstrated that the treatment process followed first-order kinetics with optimal operation at a hydraulic retention time of 0.3 h. Treatment capacity of 2 m3/day was feasible with the present system, which had a modest footprint area of 0.68 m2. Economic analysis demonstrated a breakeven period of between two to six years depending on the daily treatment volume. Higher water costs favor graywater treatment, especially when power costs are modest or low.

More Information

For more information regarding the article, please visit: American Water Works Association

For more information on Geosyntec's graywater treatment practice, contact Zita Yu at This email address is being protected from spambots. You need JavaScript enabled to view it. or Mark Hanna at This email address is being protected from spambots. You need JavaScript enabled to view it..