微生物脱盐燃料电池的产电-脱盐研究

Study on Electricity Generation-desalination of Microbial Desalination Fuel Cell

为解决传统海水淡化技术能耗高、工艺复杂等问题,本研究构建了一种同步进行“产电-脱盐-去污”的微生物脱盐燃料电池。以启动时间、产电性能、脱盐效率为标准衡量微生物燃料电池进行海水淡化系统的可行性,并对微生物燃料电池作出优化研究。在外电路负载1000Ω的条件下,微生物燃料电池(MDC-A)的启动时间为14天,最高稳定输出电压为180mV;MDC-A的最大输出电压为648mV,总脱盐率为81.5%。在中间脱盐室使用20g/L的模拟海水情况下,加入50mM的PBS溶液的反应器(MDC-C)的最大输出电压为624mV,比加入25mM的PBS溶液的反应器(MDC-B)最大输出电压高6mV;MDC-C与MDC-B总脱盐率分别为95.5%、94.0%;MDC-C的高产电效率的稳定时间为150min,比MDC-B高25%。与未加入磷酸盐缓冲液的反应器(MDC-A)相比,MDC-C的最大平均功率密度高33.13%。而三套反应器的最大功率密度值则出现在MDC-A的第一周期,为57.60×10^-2W/m^2。结果表明微生物燃料电池可用于海水淡化系统;pH稳定性的增加会提高电池的产电性能和脱盐效率。因此,微生物燃料电池进行海水淡化系统的优化工艺需要进一步深入探究。

In order to solve the problems of high energy consumption and complicated process of traditional seawater desalination technology,this study constructed a microbial fuel cell that can simultaneously performs“electricity generation-desalting-decontamination”.The feasibility of using microbial fuel cells to desalinate was measured by starting time,electricity generation and desalination efficiency,and the microbial fuel cells were optimized then.Under the condition of 1000Ωexternal circuit load,the start-up time of the microbial fuel cell(MDC-A)was 14 days,and the highest stable output voltage was 180 mV.Besides,the maximum output voltage was 648 mV,and the total desalination rate was 81.5%.In the case of using 20 g/L of simulated seawater in the intermediate desalting chamber,the maximum output voltage of the reactor with 50 mM PBS solution(MDC-C)was 624 mV,which was 6 mV higher than the one of the reactor with 25 mM PBS solution(MDC-B);the total desalination ratio of the MDC-C was 95.5%.,while the same index of the MDC-B was 94.0%;the stabling time of high-efficiency power generation of MDC-C was 150 min,which was 25%higher than that of the MDC-B.The maximum average power density of MDC-C was 33.13%higher than that of the reactor without added phosphate buffer(MDC-A).The maximum power density values of the three reactors appearred in the first cycle of MDC-A,which was 57.60×10^-2 W/m^2.The results showed that the microbial fuel cell can be used for the desalination system;The increase of pH stability will improve the battery's electricity production performance and desalination efficiency.Therefore,the optimization of microbial fuel cell for desalination system needs further exploration.