Hospital wastewater needs reliable removal of organics and solids followed by verified disinfection before it leaves the site. This reference configuration combines an integrated biological plant, lamella clarification and an on-site sodium hypochlorite generator with a dedicated contact tank.
The challenge
Hospitals generate wastewater from wards, operating theaters, laboratories, laundries and kitchens. In composition it often resembles domestic sewage in organic strength, but it can carry pathogens, pharmaceutical residues and variable amounts of disinfectants and detergents. Most jurisdictions therefore require hospitals to treat and disinfect wastewater on site before it enters the public sewer or a watercourse, with limits on fecal coliforms and residual chlorine.
Hospital sites are also constrained. The plant is often placed in a basement, a service yard or beside a car park, close to patients and staff. It must be compact, low-odor, quiet and dependable, because an outage cannot be solved by shutting off the source. Chemical handling should be minimized for safety.
Our solution
The reference solution is an integrated hospital wastewater plant in which biological treatment and clarification are followed by a dedicated disinfection stage fed by an on-site electrolytic sodium hypochlorite generator.
A packaged A/O (anoxic/oxic) or contact-oxidation biological system reduces organics and ammonia. A lamella (inclined plate) clarifier then separates biological solids in a small footprint, with optional coagulant dosing to polish suspended solids. Clarified water flows to a baffled contact tank where hypochlorite is dosed in proportion to flow, giving the required contact time before discharge. A dechlorination step can be added where receiving water limits on residual chlorine are strict.
All tanks can be covered and vented through an odor-control system, and the whole line runs from a PLC with flow-paced dosing and alarms.
Process flow
- Screening – a mechanical bar screen removes coarse solids, gloves, swabs and packaging. Screenings are bagged for disposal as healthcare waste.
- Equalization and pre-treatment – an equalization tank buffers flow and load; optional pre-disinfection can be applied where infectious wards discharge separately.
- Anoxic and aerobic treatment – the biological plant removes BOD, COD and ammonia.
- Lamella clarification – inclined plates settle biological solids; settled sludge is returned or wasted.
- Disinfection contact tank – sodium hypochlorite is dosed at the tank inlet and the baffled channel provides plug-flow contact time.
- Optional dechlorination – residual chlorine is reduced before discharge if required.
- Sludge treatment – waste sludge is disinfected, thickened and dewatered on a compact screw press.
Scope of supply
- Integrated biological wastewater treatment plant with equalization, anoxic and aerobic sections
- Mechanical bar screen from our screening equipment range
- Lamella inclined-plate clarifier with sludge hopper and optional coagulant dosing
- Electrolytic sodium hypochlorite generator with brine system, product storage tank and flow-paced dosing pumps
- Disinfection contact tank and optional dechlorination dosing
- Compact screw press sludge dewatering unit for disinfected sludge
- Optional medical waste incinerator for screenings, cake and other healthcare waste where permitted
- PLC panel, residual chlorine and flow instrumentation, commissioning and training
Why this configuration works
Disinfection is more effective after good solids removal. Chlorine-based disinfection works best on clear water. By placing biological treatment and lamella clarification ahead of the contact tank, the configuration lowers the chlorine demand and protects against particle-shielded pathogens.
Chemical risk is reduced. The generator makes low-concentration hypochlorite on demand, so the hospital does not need to receive, store or handle chlorine gas or large volumes of concentrated bleach. Raw materials are food-grade salt, water and electricity.
Dosing is controlled. Hypochlorite is paced to flow, and residual chlorine is monitored at the outlet so the operator can confirm compliance and avoid overdosing.
The footprint suits hospital sites. Integrated tanks and inclined-plate settling keep the plant compact enough for a basement or service yard, and covered tanks limit odor near patients and staff.
Waste streams are closed out. Disinfected sludge is dewatered to reduce volume, and solid residues can be routed to licensed disposal or on-site incineration, giving the hospital one coordinated solution.
Discharge standards for healthcare wastewater differ by country and sometimes by hospital type, so contact time, coliform limits and residual chlorine targets are confirmed against the applicable permit during design.
To receive a proposal, send the bed count, daily water consumption, any influent analysis and the applicable discharge standard to [email protected] or via our contact page.
Reference configuration — final design depends on site data.
Design basis
| Design flow | 50–1,000 m³/day |
|---|---|
| Influent COD | ≤ 300 mg/L (typical general hospital) |
| Influent TSS | ≤ 150 mg/L (typical) |
| Disinfectant | On-site NaOCl, typically 0.6–1.0% available chlorine |
| Contact time | Typically ≥ 1 h, or as required by local regulation |
| Target effluent | Per local discharge permit (coliform limit and residual chlorine) |
