|信息来源： 华恒 | [ 2019-04-09 ] 点击量： 419|
Water pollution refers to the use value of water reduced or lost by harmful chemicals and turned into water polluting the environment.According to a survey by world authorities,80%of all kinds of diseases in developing countries are spread by drinking unsanitary water,which causes at least 20 million deaths worldwide every year.Therefore,water pollution is called"the world's number one killer".
Water pollution is mainly caused by pollutants produced by human activities.It includes four parts:mine pollution source,industrial pollution source,agricultural pollution source and living pollution source.Although the proportion of hospital sewage in domestic sewage is relatively small,it inevitably produces wastewater with direct or indirect infectivity,toxicity and other harmful effects during the operation of the hospital.Medical sewage containing pathogenic microorganisms has the characteristics of space pollution,acute infection and latent infections.If it is not treated harmlessly,such as disinfection and inactivation,it will do so.Directly discharged into urban sewers often results in water and soil pollution,and serious diseases,leading to outbreaks and epidemics of water-borne infectious diseases.
In March this year,the Beijing Water Administration Supervision Brigade launched special law enforcement actions on 55 medical institutions in six districts of the city.The results showed that 25 medical institutions had excessive drainage quality,and 4 medical institutions had undocumented drainage.In the water quality test,it was found that medical institutions exceeded 1400 times the standard in fecal coliform flora during the special inspection.If microorganisms exceed the standard of food,it is easy to suffer from intestinal diseases such as dysentery,which may cause vomiting,diarrhea and other symptoms,endangering human health and safety.
Water shortage and accidents caused by pollution not only stop production of factories,reduce production of agriculture and even stop harvest,but also cause adverse social impact and greater economic losses,which seriously threaten the sustainable development of society and the survival of mankind.Therefore,for medical wastewater containing chemical substances,radioactive wastewater and pathogens,it must be treated by medical sewage treatment equipment before discharging,especially in infectious disease wards such as hepatitis,which can only be discharged after disinfection.
The process of"pretreatment first-level intensified treatment disinfection"can be used for sewage treatment in general hospitals(without infectious wards).Particulates carrying viruses and pathogens are removed by coagulation sedimentation(filtration),automatic grilles are set at the front of the regulating tank,lifting pumps are set in the regulating tank,sewage is lifted into the coagulation sedimentation tank for coagulation sedimentation,and the effluent of the sedimentation tank is disinfected into the contact tank for discharge up to the standard.Infectious disease hospitals(including general hospitals with infectious wards)and general hospitals discharged into natural waters use biological aerated filter+chlorine dioxide disinfection sewage treatment process.The process is that raw sewage is first removed floating matter by grille,then particulate matter such as mud and sand is separated by sedimentation tank,and then uniformly adjusted and pumped to BAF for biological treatment.After chlorine dioxide disinfection,the effluent is discharged to the standard and backwashed.The effluent is returned to the sedimentation tank,and the sewage after precipitation is recycled.
With the progress of science and technology,wastewater can also be a valuable resource,which should be utilized to a large extent.Improving the recycling efficiency of medical wastewater can not only reduce pollutant discharge,but also save limited water resources.With the increasing shortage of water resources and the increasing urgency of environmental pollution control,the development trend of wastewater reuse will be to use advanced technology,technology and equipment to treat wastewater and discharge it,increase the number of recycled water,and improve the reuse rate of water resources.