Introduction
In the complex environment of hospitals, the treatment of pollutants and wastewater must adhere to systematic protocols. Indiscriminate mixing of waste streams only exacerbates downstream processing challenges. Thus, classified treatment is a critical prerequisite for effective medical wastewater management. Below is a detailed breakdown of the classification and treatment strategies for medical wastewater:
1.High-Risk Pathogenic Waste
Culture media for pathogens, toxic preservation solutions, and other high-risk waste shall first undergo pressure steam sterilization at the department level. Post-sterilization, they are managed as general infectious waste in accordance with relevant regulations.
2.Infectious Wastewater
Sputum from infectious patients (e.g., tuberculosis patients), post-laboratory sputum samples, and contaminated waste—including collected sputum from patients across departments—are transported to the sputum processing room. These materials are either subjected to high-temperature boiling for 30 minutes or treated with 2000 mg/L chlorine-containing disinfectant for 30 minutes before being discharged into the medical wastewater treatment system.
3.Radioactive Liquid Waste
Radioactive liquid waste is discharged via dedicated pipelines into isolated sewage tanks. After undergoing decay processes to reduce radioactivity to permissible levels, it is routed to the medical wastewater treatment system.
4.Chemical Waste
– Developer Waste: Developer solutions from radiology departments are directly discharged into the medical wastewater treatment system.
– Fixer Waste: Fixer solutions are collected in leak-proof containers and transferred to qualified recycling companies for professional disposal, as they contain heavy metals and other hazardous substances requiring specialized treatment.
5.General Medical Wastewater
General medical wastewater is conveyed to the sewage treatment station via the hospital’s drainage system. At the station, it undergoes standardized treatment processes—including sedimentation, disinfection, and sterilization—using specialized equipment and chemical agents, in compliance with national and local wastewater discharge standards.
Disinfection and Monitoring
Chlorine disinfection is a commonly employed method for medical wastewater. To ensure disinfection efficacy and prevent excessive chlorine discharge, real-time monitoring of total residual chlorine (TRC) in effluent is mandatory. The RCl900 Total Residual Chlorine Online Analyzer is installed at both the influent and effluent points of the treatment system, enabling precise control of chlorine disinfectant dosage and ensuring compliance with regulatory requirements.
Supplementary Requirements
1.Equipment and Reagent Qualification: Manufacturers of medical wastewater treatment equipment and chemical reagents must hold valid certifications (e.g., ISO 9001, environmental management system certifications) to ensure product quality and compliance with industry standards.
2.Online Monitoring: Post-treatment medical wastewater requires continuous online monitoring, which may be commissioned to third-party testing institutions with CMA (China Metrology Accreditation) or CNAS (China National Accreditation Service for Conformity Assessment) qualifications. Key monitoring indicators include total residual chlorine, coliform bacteria, chemical oxygen demand (COD), total phosphorus (TP), and ammonia nitrogen (NH₃-N), among others.
Basic Treatment Processes
Medical wastewater treatment typically follows two-stage processes:
– Primary Treatment: Hospital sewage → Septic tank → Equalization tank → Disinfection contact tank → Discharge to municipal sewage system.
– Secondary Treatment: Hospital wastewater → Septic tank → Equalization tank → Biochemical tank → Sedimentation tank → Disinfection contact tank → Discharge to municipal sewage system.
This classification-based approach ensures targeted, efficient, and compliant management of medical wastewater, minimizing environmental risks and safeguarding public health.
