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Pharmaceutical wastes contained organic solvents are one of the major complexand toxic industrial wastes characterized high COD and resistance to biologicaltreatment. In order to investigate pharmaceutical, particularly, chlotinated solventsbiodegradation process under low temperature deriving economical benefits such asbiogas recovery, rational space utilization, sludge storage and disposal costsreduction, wastewater reuse optimization, methane production rate, excess sludgegeneration under low temperature and short HRT were analyzed. The up-flowanaerobic sludge bed reactor (UASB) coupled with the aerobic membranebioreactor (MBR) were selected for biological treatment study. The UASB-reactor operation under temperatures lower 35℃ revealed the highestCOD removal efficiency at 20 ℃ - 89 ％. Meanwhile, methane production at 25 ℃reached the highest rate - 4.2 L/d, and only 3.8 L/d - at 20 ℃. Nevertheless, 20 ℃was selected as optimum temperature due to negligible difference in methaneflowrate compared with energy input to heat reactor up to 25 ℃. The different chlorinated solvents loads regarded to UASB-performanceanalysis resulted in strong inhibition effect on anaerobic microbiology. From theother hand it is possible to proceed higher solvents loads with sufficient carbonsupply. For this purpose methanol was used and resulted in 5.45 L/d of the average methane flowrate and 88.24 % COD removal efficiency. The aerobic process observation under different HRT intervals revealed thehighest TOC removal at 6 h and 10 h - 91.25 % and 94.62 %, respectively while theCOD elimination - 91.8 % and 92.3 %, respectively. A long SRT and a short HRT inevitably heightened biomass concentrationfrom 2.06 g/L to 9.02 g/L at 10 h and 4 h, respectively that may facilitate thebiodegradation of refractory pollutants. On the other hand, it may have two negativeeffects. According to the obtained results UASB-MBR combined technology reducesannusl electricity consumption up to 27 %, excess sludge production up to 54 %.The technology also makes credible wastewater reuse in exhausted gases treatmentbiofilters which, in turn, decreases water consumption and wastewater generation.