Decentralized drinking water treatment is limited by supply of service, consumables, spare parts and in particular, power. Therefore, gravity-driven dead-end ultrafiltration is applied to purify surface water with high suspended solid loading. To obtain high flux in the long term, an effective membrane backwash is mandatory. Also, disinfection and cleaning is required regularly. Here we propose a new process coping with these particular challenges in decentralized water production: Temperature Enhanced Backwash. Herein, the membrane is backwashed at elevated temperature and corresponding steam pressure. A mathematical description of the Temperature Enhanced Backwash reveals that membrane pores are filled predominantly with liquid phase, irrespectively of whether membranes are charged with saturated steam or boiling liquid. A steam - water mixture is discharged at the module outlet suggesting evaporation at the end of the pores. This evaporation at membrane - fluid interface supposedly creates high volume fluxes shearing off potential fouling layers. Combined with gravity-driven filtration, the overall process potentially can cope with highly intermittent electrical power supply or even its absence. The methodology shows competitive cleaning efficacy compared to mechanical backwashing as demonstrated experimentally using silica nanoparticles, humic acid and river water.

分散式饮用水处理受到服务，消耗品，备件尤其是电力供应的限制。因此，应用重力驱动的死角超滤来纯化具有高悬浮固体负荷的地表水。为了长期获得高通量，必须进行有效的膜反冲洗。此外，还需要定期进行消毒和清洁。在这里，我们提出一种新工艺来应对分散水生产中的这些特殊挑战：温度增强型反冲洗。在此，在升高的温度和相应的蒸汽压力下对膜进行反洗。温度增强型反冲洗的数学描述表明，无论膜中充满了饱和蒸汽还是沸腾的液体，膜孔中都主要填充有液相。蒸汽-水混合物从模块出口排出，表明在孔的末端蒸发。膜-流体界面处的这种蒸发据说会产生高流量，从而剪切掉潜在的污垢层。结合重力驱动的过滤，整个过程可能可以应对高度间歇性的电力供应，甚至没有电力供应。与使用硅胶纳米颗粒，腐殖酸和河水进行的实验证明的机械反冲洗相比，该方法显示出极好的清洁效果。整个过程可能会应付高度断续的电源，甚至不使用电源。与使用硅胶纳米颗粒，腐殖酸和河水进行的实验证明的机械反冲洗相比，该方法显示出极好的清洁效果。整个过程可能会应付高度断续的电源，甚至不使用电源。与使用硅胶纳米颗粒，腐殖酸和河水进行的实验证明的机械反冲洗相比，该方法显示出极好的清洁效果。