Medical wastewater generated in hospitals originates from diverse sources, including operating rooms, laundries, laboratories, and patient wards, with primary contaminants encompassing organic pollutants, viruses, and pathogenic microorganisms. To prevent the direct discharge of medical wastewater, robust treatment processes must be implemented to safeguard groundwater, surface water, and other water resources. This article, in collaboration with Muditech, aims to elaborate on the key knowledge of medical wastewater treatment processes.
A basic medical wastewater treatment process typically involves grid screening for debris removal followed by disinfection prior to discharge. Chlorine dioxide is commonly employed as a disinfectant to ensure compliance with regulatory standards for total residual chlorine and total bacterial count. However, this disinfection method fails to remove organic pollutants. To achieve comprehensive compliance with discharge standards, hospitals often integrate biological aerated filter (BAF) processes into their treatment systems. Additionally, constraints such as limited land availability for treatment facilities and the presence of residual disinfectants in the wastewater must be considered during process design.
Medical wastewater treatment involves not only the removal of domestic sewage components but also targeted disposal of chemical substances and pathogenic microorganisms. After treatment, medical wastewater shall be subject to strict inspection, and Medical Wastewater Online Monitoring shall be carried out to confirm all hazardous substances comply with relevant regulatory standards before discharge. It is worth noting that the wastewater generated from isolation wards for localized infectious diseases such as hepatitis must be disinfected before discharge. For hospitals that are not equipped with centralized wastewater treatment facilities, infectious faecal waste needs to be separately disinfected first to realize harmless treatment.
Common disinfectants include bleaching agents, sodium hypochlorite, and liquid chlorine. For wastewater containing radioisotopes, treatment must adhere to specific protocols for radioactive materials. During the treatment process, sediments may harbor high concentrations of bacteria, viruses, and parasites, which necessitate additional disinfection.
It is important to note that chlorine-based disinfectants, widely used in hospitals, can generate toxic and carcinogenic byproducts as residual chlorine levels increase during disinfection. Thus, operators must control residual chlorine concentrations to prevent contamination of drinking water sources and subsequent harm to human health. The RCl900 Online Total Residual Chlorine Analyzer can be utilized for real-time monitoring of residual chlorine levels, enabling data-driven adjustment of chlorine dosage.
