Experiment Study on Sewage Treatment in Qinghai-Tibet Railway

Considering the characteristics of the domestic sewage at the small stations in the Qinghai-Tibet railway and using the abundant solar radiant heat on the Qinghai-Tibet plateau, the ecological greenhouse is established, which could constitute a small semi-closed artificial environment suited normal sewage biological treatment under the atrocious natural condition of the Qinghai-Tibet plateau. It could provide dynamic heat balance and the cyclic balance of O₂-CO₂ for sewage biological treatment. Comparing two different biological treatment processes in the lab, we adopted the combination process of 4 levels rotating biological contactor and soil treatment to treat the sewage on the spot. The field test results show that the water quality of the sewage treated by this system can meet the national discharge standard Class I. This system solves two main difficulties in sewage treatment and vegetable planting effectively.