Phosphate pollution in lakes poses an intractable remediation challenge. Accumulated stocks of phosphorus in sediments cause high concentrations in the overlying water despite elimination of external sources. We propose to use sediment microbial fuel cells (SMFCs) for lake remediation by sediment phosphorus immobilization. The hypothesis is that SMFCs can increase sediment redox potential at the top layer, and that such changes will allow the sediment to retain phosphorus as immobile species. This study placed an emphasis on scalability, practicality, and use of low-cost materials. Stainless steel net was selected as electrode material, and modifications were tested: (i) chronoamperometric operation with anode poised at +399 mV (versus standard hydrogen potential); (ii) injection of graphite slurry; and (iii) coating with nickel-carbon matrix. Stainless steel electrodes were implemented in laboratory microcosms (1.3 L) and at field scale in a eutrophic freshwater lake. All tests were carried out in untreated sediment and water from Lake Søllerød, Denmark. Phosphate immobilization was shown at lab scale, with 85% decrease in overlying water using steel electrodes. At field scale maximum phosphate decrease of 94% was achieved in the water body above a 16 m² stainless steel SMFC electrode. Results are promising and warrant further study, including remediation trials at full scale. Added benefits include degradation of sediment organic matter and pollutants, inhibition of methane and sulfide emission and production of electricity.

湖泊中的磷酸盐污染带来了难以克服的修复挑战。尽管消除了外部污染源，但沉积物中磷的积累却导致上覆水中的高浓度。我们建议使用沉积物微生物燃料电池（SMFCs）通过固定化沉积物磷来修复湖泊。假设是SMFCs可以增加顶层的沉积物氧化还原电势，并且这种变化将使沉积物将磷保留为不可移动的物种。这项研究着重于可伸缩性，实用性和低成本材料的使用。选择不锈钢网作为电极材料，并进行了修改测试：（i）计时电流法操作，阳极保持在+399 mV（相对于标准氢势）；（ii）注入石墨浆；（iii）用镍-碳基体涂层。在实验室缩影（1.3升）中和在富营养化淡水湖中以田间规模实施了不锈钢电极。所有测试均在丹麦Søllerød湖未经处理的沉积物和水中进行。在实验室规模上显示了磷酸盐固定化，使用钢电极的上覆水减少了85％。在田间尺度上，在16 m以上的水体中最大磷酸盐减少量达到94％²不锈钢SMFC电极。结果令人鼓舞，值得进一步研究，包括全面的修复试验。额外的好处包括沉积物有机物和污染物的降解，抑制甲烷和硫化物的排放以及发电。