Water regeneration from human urine by vacuum membrane distillation and analysis of membrane fouling characteristics

摘要: Abstract As a potential high-efficiency water circulation technique in some fields, such as space station that is abundant with vacuum and cooling resources solar power, membrane distillation (VMD) process was employed for regeneration from human urine. Particularly, fouling characteristics were investigated. The separation performances including the flux well chemical oxygen demand (COD), ammonia-nitrogen concentration, conductivity value of distillates studied experimentally. results indicated increased increasing feed temperature, but decreased time. In distillates, COD reduced time went up gradually rose temperature due to thermal decomposition urea. VMD processes 500 mL urine after 16-h operation had high removal rates 99.3–99.5%, removals reached 40.6–75.1%. corresponding yields 31.9–48.6%. Furthermore, effects degree permeate side, cross-flow flowrate on experimentally evaluated. showed critical operating conditions (CFOCs) existed processes. From scanning electron microscopy photographs, it confirmed organic accompanied by salt crystals surface can be restrained effectively when carried out within CFOCs. organics, ions, ammonia-nitrogens could removed under appropriate conditions, relatively low sufficient area short heating