Aquatic environment

An innovative integrated system utilizing solar energy as power for the treatment of decentralized wastewater

Changfu Han , Junxin Liu , Hanwen Liang , Xuesong Guo , Lin Li


Received April 13, 2012,Revised July 05, 2012, Accepted , Available online February 02, 2013

Volume ,2013,Pages 274-279

This article reports an innovative integrated system utilizing solar energy as power for decentralized wastewater treatment, which consists of an oxidation ditch with double channels and a photovoltaic (PV) system without a storage battery. Because the system operates without a storage battery, which can reduce the cost of the PV system, the solar radiation intensity affects the amount of power output from the PV system. To ensure that the power output is sufficient in all different weather conditions, the solar radiation intensity of 78 W/m2 with 95% confidence interval was defined as a threshold of power output for the PV system according to the monitoring results in this study, and a step power output mode was used to utilize the solar energy as well as possible. The oxidation ditch driven by the PV system without storage battery ran during the day and stopped at night. Therefore, anaerobic, anoxic and aerobic conditions could periodically appear in the oxidation ditch, which was favorable to nitrogen and phosphate removal from the wastewater. The experimental results showed that the system was efficient, achieving average removal efficiencies of 88% COD, 98% NH4+-N, 70% TN and 83% TP, under the loading rates of 140 mg COD/(g MLSS·day), 32 mg NH4+-N/(g MLSS·day), 44 mg TN/(g MLSS·day) and 5 mg TP/(g MLSS·day).

Copyright © Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.京ICP备05002858号-3