Marine wastewater treatment
sewage treatment plants
reliable, imo-compliant treatment for any crew size.
Sewage Treatment Plants are the ultimate solution for dealing with onboard wastewater. Widely installed on merchant vessels, offshore platforms and naval ships worldwide, they are renowned for their treatment effectiveness, compact footprint and low maintenance.
Treatment capacity
10 – 1,000 people onboard
Type approval
IMO MEPC 159(55) & MEPC 227(64) MED
Technologies
Biological (STPN/PRBN) & Membrane Bio-Reactor (MBR)
sewage treatment plants
Sewage Treatment Plants are the ultimate solution for dealing with onboard wastewater. Widely installed on merchant vessels, offshore platforms and naval ships worldwide, they are renowned for their treatment effectiveness, compact footprint and low maintenance.
by the numbers
Two proven treatment technologies, one shared commitment: reliable, IMO-compliant sewage treatment for any crew size.
People on board
10–1,000
Type-approved to
MEPC 159(55)
& MEPC 227(64) MED
Units at sea
1,000+
ships worldwide
biological treatment — stpn & prbn series
Cutting-edge technology applied to the design of sewage treatment. Decades of operation of Sewage Treatment Plants onboard hundreds of vessels worldwide are the strongest proof of their reliability, and the reason for the loyalty of our customers.
STPN Series
Black & grey water treatment
PRBN Series
Reduced-footprint, black water only
Crew range
10–400 people
Both series are IMO MEPC 159(55) & MEPC 227(64) MED Type Approved and are the perfect choice for almost all standard newbuild and retrofit projects.
main features
- Biological plants
- IMO MEPC 159(55) & MEPC 227(64) MED Type Approved
- STPN Series: for black and grey water treatment
- PRBN Series: reduced footprint, black water treatment only
- Wide range for crews from 10 to 400 people
main advantages
- Compact solution — modular or containerized versions available
- Easy installation
- Compatible with all vacuum systems
- Low maintenance required
- Aerobic process: no risk of odour or methane emissions
- Simple, reliable & excellent quality-price ratio
membrane bio-reactor — mbr series
A compact and reliable alternative sewage treatment plant, built for high crew counts or high-quality effluent requirements — especially suited to offshore and Navy projects.
Crew capacity
100–1,000
Membrane supplier
Mitsubishi Rayon
Membrane-type plants use a physical barrier to solids and particulate matter, delivering excellent effluent quality without chemical disinfection.
Read more on MBR specifications →main features
- Membrane-type plants: physical barrier to solids & particulate matter
- IMO MEPC 159(55) & MEPC 227(64) MED Type Approved
- MBR Series: for high crews from 100 to 1,000 people
- Mitsubishi Rayon membranes
- Best option for Navy and Offshore projects
main advantages
- Latest state-of-the-art water filtration technology
- Reduced footprint
- Excellent effluent quality
- Optimal solution for large-crew vessels
- Environmentally friendly — no chemicals required for disinfection
- Fully customizable
two technologies, one goal
Choose biological treatment for standard vessel projects, or membrane bio-reactor technology when a larger crew or higher effluent quality demands it.
modular & containerized installation
Every Sewage Treatment Plant is designed as a compact solution, available in modular or fully containerized versions, and is compatible with all vacuum collection systems for straightforward retrofit or newbuild installation.
Suitable for merchant, offshore and naval vessels alike.
treatment process
From aeration to discharge — how Sewage Treatment Plants turn onboard wastewater into IMO-compliant effluent.
Built to the highest standard
compliance & certification
Every Sewage Treatment Plant is designed, tested and certified to meet the strictest international requirements for marine wastewater discharge, giving shipowners full confidence in class approval and survey.
Certified quality across the full Sewage Treatment Plant range.
imo type approval
Sewage Treatment Plants are Type-Approved under IMO MEPC 159(55) and MEPC 227(64) MED — the international standards governing sewage treatment equipment for ships — ensuring compliant discharge anywhere in the world, including designated Special Areas.
Approvals apply to both the biological (STPN / PRBN) and membrane bio-reactor (MBR) series.
environmentally friendly by design
The aerobic biological process eliminates the risk of odour or methane emissions, while the MBR Series requires no chemicals for disinfection — delivering fully compliant, environmentally responsible treatment without compromise.
Aerobic and membrane technologies both minimise environmental impact while meeting IMO discharge requirements.
sewage treatment plants
Full technical specifications, type approvals and application markets for the Sewage Treatment Plant range.
biological sewage treatment plant — stpn & prbn series
Type
Biological plant, aerobic extended-aeration process
STPN Series
Black and grey water treatment
PRBN Series
Reduced footprint; black water treatment only
Crew capacity
10 – 400 people on board
Installation
Compact — modular or containerized versions available; compatible with all vacuum systems
Maintenance
Low maintenance required
Emissions
Aerobic process — no risk of odour or methane emissions
Type approval
IMO MEPC 159(55) & MEPC 227(64) MED
membrane bio-reactor sewage treatment plant — mbr series
Type
Membrane-type plant — physical barrier to solids & particulate matter
Crew capacity
100 – 1,000 people on board
Membrane
Mitsubishi Rayon membranes
Disinfection
No chemicals required — environmentally friendly technology
Footprint
Reduced, compact footprint
Best suited for
Navy and offshore projects; large-crew vessels
Customization
Fully customizable
Type approval
IMO MEPC 159(55) & MEPC 227(64) MED
type approvals & certification
IMO approval
MEPC 159(55) & MEPC 227(64) MED — sewage treatment equipment for ships
Quality certification
ISO 9001, Bureau Veritas certified
Classification societies
DNV Type Approval, ABS Type Approval
Approvals and certifications shown are those held for our Sewage Treatment Plant range; confirm the specific certificate applicable to your vessel's flag.
markets & applications
Navy
Naval vessels requiring robust, mission-ready treatment systems
Marine
Merchant vessels — the STPN/PRBN series is the standard choice for most standard projects
Offshore
Offshore platforms — the MBR series is the preferred choice for high crew or high-quality effluent requirements