Retrofit Solutions for Marine and Offshore Wastewater Systems
No two vessels are alike. That’s why our retrofit solutions are never standard.
Why Choose G&O Bioreactors for Your Retrofit Project?
Whether your project involves limited space, tight timelines, or full system overhauls, G&O Bioreactors offers full-scope retrofit solutions tailored to meet the specific technical and regulatory needs of each vessel or offshore installation.
With decades of experience designing bioreactors for black and grey wastewater, our team specialises in custom-building and integrating biological wastewater treatment systems on board even the most complex marine and offshore infrastructures.
We handle the complex and the simple
From modular builds for remote offshore assets to compact bioreactor retrofits for existing engine rooms, our expertise covers all levels of complexity. Our in-house engineering team collaborates directly with your yard or technical staff to ensure exact fit, minimum downtime, and full compliance.
Modular, Scalable & Site-Ready
Many vessels present challenging retrofitting conditions due to space constraints or old infrastructure. Our modular design philosophy solves this by using smaller, stackable units that are assembled onsite. This ensures:
- Seamless integration with existing piping and structures
- Reduced need for structural modifications
- Faster and lower-cost installation with minimal disruption
- High reliability from day one
Engineering Excellence and Long-term Efficiency
Each retrofit project is approached as a unique development task, not just a standard product delivery. Our engineering process is drawing-intensive and carefully adapted to the vessel’s existing layout and conditions. We provide complete documentation to support class approvals, including DNV, UK MER, and RoHS compliance, and ensure that all installations are ready for future dismantling through Green Passport certification. Where required, our systems are configured to integrate directly into the vessel’s existing monitoring and alarm systems, ensuring seamless operation and full regulatory traceability.
In contrast to many conventional wastewater treatment systems, G&O Bioreactors do not rely on complex PLC controls or chemical dosing. This simplifies installation and reduces both commissioning and maintenance costs. It also removes the environmental and operational risks associated with chlorine-based disinfection systems, offering consistent uptime, fewer alarms, and easier day-to-day handling for crew onboard. As a result, our retrofit solutions can reduce engineering hours by up to 100 hours per vessel – a substantial saving in both time and total cost of ownership.
Retrofit case:Retrofitting Offshore Wastewater Treatment Plants
A major offshore energy company faced pressure to replace its outdated wastewater treatment system. The existing setup no longer met effluent standards and lacked capacity for an expanded crew. Conventional systems could not be installed due to space limitations. G&O Bioreactors delivered a custom, modular retrofit that integrated seamlessly with existing infrastructure, without interrupting operations. The result? A fully compliant system with increased capacity and zero operational downtime. Read the full case here.
| Customer | Offshore energy company |
| Application | Offshore Living Quarters |
| System | Custom G&O Bioreactor Retrofit |
| Challenge | Space constraints, outdated system |
| G&O Work Scope | Modular retrofit design, engineering & documentation |
| Key Results | Full IMO compliance, increased capacity, no downtime |
Global Service and Support
All retrofit deliveries include full lifecycle support:
- Worldwide network of authorised service partners
- 24/7 direct service availability
- Genuine G&O bioreactors spare parts with 12-month warranty
- Training for onboard personnel
- Optional remote diagnostics
Book a free retrofit consultation today
Whether you need to replace an outdated system, upgrade to meet new capacity, or prepare for future IMO regulations, G&O Bioreactors delivers a retrofit solution that fits – technically, operationally, and environmentally.