Hospital wastewater (commonly known as hospital sewage) refers to various types of wastewater discharged by hospitals into the natural environment or urban pipe systems. It has wide-ranging sources, complex composition, and high risks of infectiousness, toxicity, and radioactivity, requiring strict treatment before discharge. The nature of hospital sewage refers to wastewater generated by hospitals containing pathogens, heavy metals, disinfectants, organic solvents, acids, alkalis, and radioactivity. The main departments and facilities in hospitals that generate sewage include: treatment rooms, laboratories, wards, laundry rooms, X-ray film processing rooms, animal facilities, isotope therapy and diagnostic facilities, operating rooms, etc.; domestic sewage discharged by hospital administration and medical staff; and drainage from canteens, single dormitories, and family dormitories.
1. Sources: Hospital wastewater mainly originates from multiple functional areas within the hospital, including:
1.1 Treatment and examination areas: such as outpatient departments, emergency rooms, laboratories, X-ray/CT imaging departments (film processing rooms), isotope diagnostic and treatment rooms, etc.
1.2 Treatment and Nursing Areas: Wards (including general wards and infectious disease wards), operating rooms, autopsy rooms, animal facilities, etc.
1.3 Logistics and Auxiliary Areas: Laundry rooms, pharmacies, canteens, single dormitories, family dormitories, and domestic sewage discharged from administrative areas, etc.
1.4 Special Discharge Sources: Excrement contaminated with infectious disease pathogens (such as feces) must be strictly disinfected before being discharged into dedicated septic tanks or sewage treatment systems.
2. Composition: Hospital wastewater has an extremely complex composition, mainly containing the following major categories of pollutants:
2.1 Pathogenic Microorganisms: Such as bacteria, viruses, parasite eggs, etc., at extremely high concentrations (the total bacterial count in raw wastewater can reach over 10^8 CFU/mL), posing a major risk of disease transmission. 2.2 Organic and Inorganic Pollutants: Including suspended solids, floating matter, BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand), acids, alkalis, heavy metals (such as mercury and lead), drug residues, disinfectants (such as chlorine-containing compounds), organic solvents, and nutrients (such as nitrogen and phosphorus).
2.3 Radioactive Pollutants: Wastewater from isotope diagnostics and treatment departments containing radioactive nuclides.
2.4 Other Special Pollutants: Such as oily wastewater and film processing wastewater, originating from the activities of specific departments.
