At G&O Bioreactors, we provide advanced biological solutions that function as next-generation marine sewage treatment plants—designed to deliver reliable performance, reduced operational complexity, and long-term cost savings.

A marine sewage treatment plant is a system installed onboard ships or offshore platforms to treat black and grey water before discharge into the sea. These systems are designed to remove organic matter, nutrients, and harmful bacteria in compliance with international environmental standards such as IMO MEPC.227(64).

Traditional sewage treatment plants often rely on chemical dosing and complex control systems. In contrast, biological systems use naturally occurring microorganisms to break down contaminants in a more sustainable and operationally efficient way.

G&O Bioreactors offer a biological marine sewage treatment plant that eliminates many of the challenges associated with conventional systems. 

Key advantages: 

• No chemical dosing required 
  Avoid the risks and logistics associated with chemical handling and storage onboard. 

• Stable and reliable operation 
  Biological processes ensure consistent treatment performance without frequent system adjustments. 

• Reduced maintenance requirements 
  Fewer mechanical components and no chemical dependency reduce downtime and service needs. 

• Lower total cost of ownership
  Minimise operational costs over the vessel’s lifetime. 

All marine sewage treatment plants must meet strict discharge requirements. G&O Bioreactors are designed to comply with:

• IMO MEPC.227(64) 

• DNV type approval 

• Additional regional certifications (e.g. Transport Canada, UK MER) 
  

Our systems ensure that treated effluent meets current and future environmental standards supporting shipowners in maintaining compliance and avoiding costly penalties. 

Whether for new vessels or retrofit installations, flexibility is critical. 

Our modular design approach allows the system to: 

• Fit within existing space constraints onboard 

• Integrate seamlessly with current piping and infrastructure 

• Be installed with minimal downtime 
  

This makes G&O Bioreactors an ideal solution for upgrading or replacing an existing marine sewage treatment plant. 

A complete marine sewage treatment plant must manage both: 

• Black water – wastewater from toilets containing high levels of organic matter and pathogens 

• Grey water – wastewater from showers, sinks, and galleys with lower contamination levels 
  

Our bioreactor systems are designed to treat both streams efficiently in a single integrated process, ensuring optimal performance and compliance. 

Biological wastewater treatment plays a key role in reducing the environmental impact of shipping. 

By avoiding chemicals and supporting natural treatment processes, G&O Bioreactors help: 

• Protect marine ecosystems 

• Reduce harmful discharge 

• Support ESG and sustainability goals 
  

This makes biological marine sewage treatment plants a future-proof solution for the maritime industry. 

Why Choose G&O Bioreactors?

With decades of experience in marine wastewater treatment, G&O Bioreactors combine engineering expertise with practical operational understanding. 

Our solutions are: 

• Proven in offshore and marine environments 

• Designed for long-term reliability 

• Supported by a global service network 

• Built with high-quality European components 
  

We work closely with shipowners, yards, and operators to deliver solutions that match real operational needs.