低温对大型海藻型微生物脱盐电池处理海产品暂养水的影响

Effect of low temperature on the treatment of seafood temporary culture water by macroalgae microbial desalination battery

摘要:

为处理海产品低温暂养水，实现系统同步产电脱盐及收获藻类生物质能源，构建三室生物阴极大型海藻新型微生物脱盐燃料电池（microbial desalination cell，MDC），实验研究了不同温度条件下，大型海藻型MDC处理海产品暂养水过程中的产电性能、脱盐效率、COD降解率、脱氮效果和藻类生长情况。结果表明：在产电性能方面：外电阻1 000 Ω负载下，8和25℃系统电压峰值无明显差异，而单个产电周期和电压稳定时间差异较大，单个产电周期分别为228和158 h，电压稳定时间分别为36和84 h；要达到相同脱盐率，8℃所需时间较25℃长，低温条件下，延长反应器运行时间可提高MDC系统脱盐率。低温时海产品暂养水中的COD、NH₄⁺-N、NO₃^--N和TN的去除率均能达到60%以上。MDC系统中的大型海藻浒苔在低温时生长缓慢，净增长量较低，但仍可保持正常生长，光合效率F_v/F_m为0.4~0.5。低温影响大型海藻型MDC的产电和脱盐性能，然而，较高的COD降解率和脱氮效果表明构建的大型海藻MDC可用于处理海产品低温暂养水。

Abstract:

In order to treat the low-temperature temporary aquaculture water of marine products, realize the synchronous power generation and desalination of the system and harvest algae biomass energy, a three-chamber biocathode macroalgae new microbial desalination fuel cell (MDC) was constructed. The power generation performance, desalination efficiency, denitrification effect and algae growth and COD degradation rate of macroalgae MDC in the treatment of temporary aquaculture water of marine products at different temperatures were experimentally studied. The results showed that in terms of power generation performance:under the load of 1 000 Ω external resistance, there was no significant difference in the voltage peak value of the system at 8 and 25℃, but there was great difference in the single power generation cycle and voltage stability time. The single power generation cycle was 228 and 158 h respectively, and the voltage stability time was 36 h and 84 h respectively; To achieve the same desalination rate, the time required at 8℃ was longer than that at 25℃. At low temperature, prolonging the operation time of the reactor can improve the desalination rate of MDC system. At low temperature, the removal rates of COD, NH₄⁺-N, NO₃^--N and TN in seafood temporary culture water could reach more than 60%. The macroalgae Ulra prolifera in MDC system grew slowly at low temperature, the net growth was low, and it still remained normal, and the photosynthetic efficiency F_v/F_m was 0.4-0.5. Low temperature affects the power generation and desalination performance of macroalgae MDC. However, the high COD degradation rate and denitrification effect show that the constructed macroalgae MDC can be used to treat low-temperature temporary aquaculture water of seafood.