微波预处理污泥上清液为燃料的微生物燃料电池的影响因素研究

Influencing factors in microbial fuel cells using supernatant fluid of microwave pretreated sludge as fuel

以微波预处理的剩余污泥上清液做为燃料,经过30 d成功地启动了单室无膜燃料电池。考察了可能影响输出功率密度的相关因素。结果表明,电池阳极面积越大,输出功率密度反而越小。阴阳极距离从5 cm缩小到0.5 cm时,输出功率密度先增加后降低,在距离为2 cm时,输出功率密度达到最大值282.7 mW/m2,说明阴阳极距离过近时溶解氧可能通过空气阴极传递到阳极,影响了阳极表面上厌氧微生物的活性。采用NaCl作为离子添加剂时,随着投加量的增加,内阻显著降低,输出功率密度相应增加,最大为362.6 mW/m2;采用最优条件时,输出功率密度成功提高到387.6 mW/m2,最大库仑效率可达79.0%,说明微波预处理可以有效提高MFC的产电效率。

A single-chamber and membrane-less microbial fuel cell was successfully started up using the supernatant fluid of microwave pretreated sludge as inoculums within 30 days.Some relevant factors which may affect output density of the microbial fuel cell were studied.The results indicated that the larger anode area of the cell made the output power density smaller.When the distance between cathode and anode decreased from 5 cm to 0.5 cm,the output power density first increased and then decreased,which mainly because the diffuseness of oxygen from the air-cathode may affect active of the anaerobic bacteria on anode.The maximum output density（282.7 mW/m^2） was observed while the distance was 2 cm.When using NaCl as an ionic additive,it had a corresponding decrease in internal resistance with the dosage increased resulting an increase in output power density the maximum of which was 362.6 mW/m^2.The output power density of the microbial fuel cell was successfully raised to 387.6 mW/m^2 and the maximum coulombic efficiency was up to 79.0% under optimal experimental conditions,which indicated the performance of MFC could be effectively improved by the microwave pretreatment.