How to Build Sewage Treatment System in the Wuhan Makeshift Hospitals?

Wuhan is the first city that the novel corona virus appears in China so that the establishment of the makeshift hospitals in Wuhan is very urgent. In the meanwhile, how to build the sewage treatment system in the hospital is also a big problem. And in order to ensure the normal operation of the sewage treatment system, the function of the ball valves should be emphasized.

1. Disinfection of Discharge Water

The core requirement of the operation of the sewage treatment system is complete disinfection. No novel corona virus is detected in the effluent, and then the sewage can be discharged to ensure the safety of all people. The disinfection equipment has various stainless steel valves, which are easy to operate. The basis of judging the degree of disinfection is the measurement value of residual chlorine. The residual chlorine must be controlled between 6.5-10mg/L. When the residual chlorine is less than 6.5mg/L, there is a risk of residual virus. When the residual chlorine is more than 10mg/L, it will cause secondary pollution. In addition, the time of disinfecting with chlorine should be more than one and half an hour, and the contact time of special infectious diseases should be extended to ensure more than two hours.

2. Control Secondary Pollution

In order to prevent the secondary pollution, impermeable membrane should be laid under the whole sewage station. Rainwater also needs to be collected into the sewage treatment station for disinfection. According to the discharge standard of water pollutants of medical institutions, the exhaust discharged from the sewage treatment station should be deodorized to ensure that the pollutants in the air around the sewage station meet the relevant requirements. In addition, the sludge produced by the hospital sewage treatment process should be disinfected. What is more, disinfection can adopt the methods of pasteurization or limestone.

3. Control the Dosage

In the primary treatment, the chlorine amount of disinfection is generally 30-50mg/L. During the secondary treatment, the chlorine amount for the contact disinfection is generally 15-25mg/L. According to the dosage of the sewage treatment station in Beijing Xiaotangshan Hospital during the period of SARS, the effective dosage of disinfection is 10mg/L, and the effective dosage of contact disinfection is 50mg/L. At the initial stage of start-up, the testing personnel should detect the residual chlorine at each place, and the virus index of the effluent should be detected as well.

4. Operation of Regulating Pool

We should regularly clean up the dirt in the pipeline and on the surface of ball valves. Generally speaking, we can clean it once a week. The regulating pool should be equipped with three sewage pumps. In general, only one pump is running. When the water inflow is increased, two sewage pumps can be started at the same time. Before opening the sewage pump, we should pay attention to opening and closing the stop valve of the sewage pump. The sewage pump will pump the water in the regulating pool to the regulating biochemical pool. In addition, the sewage pump can be controlled manually and automatically. When the sewage pump is placed in the automatic control position, it can automatically start and stop without the use of stainless steel valves.