Consumables and service parts for biological marine sewage treatment plants: corrugated-PVC biofilter media by person-equivalent rating, return-sludge diaphragm-pump kits, chlorine sensor cells and UV-C quartz sleeves — what fits what, and how to order for IMO MEPC.227(64)-era plants.
Shipboard biological sewage plants — the Hamworthy/Wärtsilä ST series and comparable makes — share a service pattern: the biofilm carrier media ages, the air-driven return-sludge diaphragm pump wears its soft parts, the disinfection stage consumes either chlorine-sensing cells or UV lamps and sleeves. All four groups are catalogue consumables:
| Group | Catalogue entries | Selection key |
|---|---|---|
| Biofilter media (corrugated PVC) | 10 PE · 25 PE · 50 PE · 100 PE · 200 PE | Plant's person-equivalent (PE) rating |
| Return-sludge pump kits | Diaphragm kit Santoprene · PTFE · Ball-valve kit · Air-motor kit | Pump make/size from the plant manual |
| Chlorine monitoring | Sensor cell 0.05–2.0 mg/L | Analyser model and range |
| UV-C disinfection | Quartz sleeve 130 W · 200 W | Lamp wattage and sleeve length |
Santoprene diaphragms suit standard sewage duty; PTFE resists aggressive cleaning chemistry. Media is cut to tower dimensions — state the plant type and PE rating from the certificate plate. Related reading: the bilge/OWS MEPC guide for the adjacent compliance system.
STP consumables are stocked as generic service lines, so lead times are short; certificates for media and UV parts travel with the shipment when requested.