微生物脱盐池同时去除废水中有机物和重金属并产电特性研究

Heavy metal organic wastewater can be harmful to the environment and human health if not properly treated. To treat this type of wastewater, currently used technologies are still limited by the requirement of intensive energy inputs and complex processes. As a novel bioelectrochemical technology, microbial desalination cells (MDCs) are widely used in the field of seawater desalination with the advantages of the low energy consumption and environmental benefits. The MDCs were adopted in this study to investigate its feasibility and performance on the treatment of organic wastewater containing copper. Results indicated that MDC could be used to treat the wastewater in terms of Cu2+ and COD removal from the middle chamber and produce electricity simultaneously. Within a cycle of operation, the average removal of Cu2+ and COD in the middle chamber was 89% ±8% and 71% ±5% respectively. Meanwhile, the maximum current density obtained in the MDC reached up to 0.72 Aom-2. By changing the initial concentration of the wastewater, the Cu2+ removal showed little difference between the cycles and all reached above 95%. With the initial concentration from 1 to 10 goL-1, the removal rate of Cu2+ increased from 3.9±0.2 to 30.8±6.1 mgo(Loh)-1. And the lowest COD removal efficiency was achieved in MDC when using 1g/L influent. In an attempt to characterize the effect of buffer capacity of catholyte on the MDC performance, the phosphate buffer showed better performance on the COD removal compared with HCl solution. The pH value of phosphate buffering catholyte showed a significant impact on the removal pathway of the Cu2+ in the cathode chamber. The MDC technology may provide a new method to offset treatment operating costs, making advanced remediation measure for difficult degraded organic matters more affordable for practical applications.