As environmental regulations continue to evolve, shipowners and operators face increasing pressure to ensure that wastewater treatment systems meet stringent international standards. One of the most important regulations governing marine sewage treatment today is IMO Resolution MEPC.227(64).  While many vessel operators are familiar with the term, fewer understand what the regulation actually requires and how it affects… Read more

What is MARPOL Annex IV?  As environmental regulations continue to evolve, wastewater management remains an important responsibility for shipowners and operators. MARPOL Annex IV sets international requirements for the prevention of pollution from sewage generated onboard ships and is designed to protect marine environments from untreated or improperly managed discharge.  MARPOL Annex IV is part of the… Read more

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. What is a Marine Sewage Treatment Plant? A marine sewage treatment plant is a system installed onboard ships or offshore platforms to treat black and grey water before… Read more

When specifications become too narrow too early, the project can effectively lock itself up, reducing technical freedom, increasing risk, and limiting the ability to choose the most suitable solution once the vessel moves from concept to detailed engineering. This is particularly visible in waste water and waste systems, where physical integration and operational realities quickly… Read more

A working asset, not a new build  The vessel, a jack-up wind turbine support vessel built in 2010, operates across Northern Europe. With cranes capable of handling loads from a few tonnes to several hundred tonnes, the ship plays a key role in offshore wind maintenance and repair.  “On a ship like this, you have to think of it as… Read more

Biological treatment of wastewater: sustainable solutions for maritime and offshore applications The biological treatment of wastewater is increasingly recognised as the most sustainable and effective way to address the unique challenges of marine and offshore environments. As regulations tighten and environmental concerns intensify, shipowners and operators are turning to advanced Bioreactors to improve compliance, reduce… Read more

Choosing the right sewage treatment plant for ships: what to look for As the maritime industry faces increasingly stringent environmental standards and operational demands, selecting the right sewage treatment plant on ships has become a critical decision for shipowners and operators. With a broad range of options available, understanding the essential considerations can help ensure… Read more

Flexible retrofit solutions for water treatment on offshore platforms Reliable water treatment on offshore platforms is essential for operational continuity, crew safety, and environmental compliance. As offshore sites evolve, either through expansion or changing crew capacity, the ability to upgrade or retrofit wastewater treatment systems becomes a decisive factor in maintaining these standards, without introducing… Read more

Biological treatment of wastewater: Enhancing vessel wastewater management The biological treatment of wastewater is a vital component of modern marine waste water management strategies. As regulatory pressure increases and environmental awareness grows, shipowners are looking towards integrating advanced solutions such as bioreactors and marine incinerators for optimal compliance and efficiency. At G&O Bioreactors, we recognise… Read more

What is a biological sewage treatment plant – and why choose one? In the maritime and offshore industries, efficient wastewater management is essential for both operational compliance and environmental protection. A biological sewage treatment plant – also known as a bioreactor for wastewater treatment – offers a proven solution, utilising the natural degradation of organic… Read more

Membrane bioreactor for wastewater treatment in marine applications As regulatory pressure on marine wastewater discharge increases, shipowners require robust, future-proof solutions for biological wastewater treatment. Traditional Moving Bed Biofilm Reactor (MBBR) systems have been widely used, but the membrane bioreactor process (MBR) offers significant advantages in terms of discharge quality and operational safety. How a… Read more

On July 1st, 2025, Finland implemented the world’s first nationwide regulation requiring all vessels, regardless of type, to meet stricter standards for onboard wastewater treatment. This legislative milestone marks a growing trend: environmental compliance in maritime operations is no longer optional—it’s essential. The implications for shipowners Finland’s legislation signals an accelerated tightening of wastewater discharge… Read more

Even in tiny amounts, chlorine is highly toxic to fish and other aquatic life. Trout larvae die at concentrations as low as 0.006 mg/L, and at just 0.1 mg/L, most marine plankton are killed. Once released, chlorine can also react with organic matter in seawater to form trihalomethanes (THMs) – a group of persistent, carcinogenic… Read more

Whether operating under strict IMO standards or working with NATO-aligned navies, regulatory compliance is at the core of every system we deliver. Our Bioreactors hold MED and IMO MEPC 227(64) certificates, and our systems are designed to meet the highest global standards for onboard wastewater treatment regardless of vessel type or operating environment. “Navigating the… Read more

What is Biological Wastewater Treatment? Biological wastewater treatment is a process that uses microorganisms to break down organic matter in sewage. This method is effective in removing contaminants from water, making it suitable for discharge into the environment. The process of biological water treatment involves three primary stages: 1. Pre-treatment (Screening Phase) Water is first… Read more

For many years, Gertsen &Olufsen has been best known for its two market-leading products: vibration compensators and bioreactors. These products have set the standard in the maritime industry and have become synonymous with quality and innovation. Now, we are taking the next step by breaking down the brand name into two distinct product names that… Read more

The Customer Challenge: Replacement for Compliance and Capacity At G&O Bioreactors, we specialise in designing bioreactors that treat wastewater biologically, ensuring operations that protect marine ecosystems from untreated wastewater. This case study explores how we provided a leading offshore operator with a tailored wastewater treatment solution, ensuring compliance and operational efficiency. A major offshore energy… Read more

As environmental regulations tighten and operational costs increase, shipowners need to make smarter investment decisions for their vessels. While the market for wastewater treatment systems is saturated with options that are initially less expensive, G&O Maritime Group offers a bioreactor system that provides significant operational advantages and long-term savings. This article explores the value propositions… Read more

The Chilean authorities have recognised our Advanced Membrane Bioreactor with a certification, marking a significant advancement in the efforts to achieve cleaner oceans. This recognition not only confirms the effectiveness of our technology but also the importance of biological treatment methods in protecting the marine environment. “While traditional wastewater treatments have relied on chemical and… Read more

While our systems are designed to handle wastewater biologically without chemicals, unexpected fluctuations or contaminants can occur. We recommend STP Solupak, as this product acts as a safety net, proactively maintaining optimal conditions for the microbes in the bioreactors. For years, G & O Bioreactors has worked closely with GNC Marine. The products offer high performance… Read more

Handling wastewater on larger ships is becoming an increasing challenge due to tighter environmental legislation and customers’ growing demand for green solutions. Danish JD-Contractors, which operates several large ships, has experienced significant problems with their maritime purification systems. Bjarne Sørensen, Marine Superintendent at JD-Contractors, says: “On our ship CABLE ONE, we had two purification systems… Read more

The tunnel is expected to play a significant role in Europe’s future sustainable transport network by encouraging the shift of freight transport from road to rail and thereby providing an efficient alternative to road transport. At Gertsen & Olufsen Bioreactors, we are proud to be part of the Fehmarnbelt Tunnel project. Our water treatment plant,… Read more

The process of biological water treatment The process of biological water treatment involves several stages.  Why use biological waste water treatment? Biological treatment of waste water is an effective and efficient way to remove contaminants from water. It is also a relatively low-cost and environmentally friendly process, as it relies on natural biological processes rather… Read more

A complete biological sewage treatment plant to be used under the most extreme conditions, made in a simple standard container; that was the task ‘India’s National Center for Antarctica and Maritime Research’ gave us. In November 2014 the plant was completed and shipped to NCAOR’s permanent research station in Antarctica via Cape Town, South Africa. Read more

‘Clean Sailing’ wrote about Lauritzen Kosan new-buildings fitted with next-generation biological sewage treatment plants. Read more