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 operational risk, and minimise long-term costs.

Biological treatment relies on naturally occurring microorganisms to break down organic contaminants in sewage and grey water. The process is typically comprised of three stages:

• Pre-treatment: Removal of large solids to protect downstream equipment.
• Biological digestion: Microorganisms metabolise organic matter into harmless by-products, mainly carbon dioxide and water, often within an aerated environment for optimal efficacy.
• Clarification and disinfection: Treated water is separated from biological sludge, then disinfected—often using chemical-free UV technology—to ensure it is safe for discharge in accordance with IMO MARPOL Annex IV and other global standards.

The biological treatment of wastewater by Bioreactors offers a significant environmental advantage compared to traditional chemical systems. By eliminating chlorine and other hazardous chemicals, the risk of toxic by-products—such as trihalomethanes (THMs)—is avoided, safeguarding fragile marine life from persistent pollution.

From an operational perspective, biological systems have fewer moving parts and no reliance on chemical dosing units, reducing both maintenance demands and the potential for costly regulatory breaches associated with chemical misdosing or stock shortages. Systems like Bioreactors are engineered with modularity and quality in mind, supporting easy installation and reliable integration with vessel layouts, including retrofits and newbuilds.

With international standards evolving—such as Finland’s nationwide mandate for biological wastewater treatment and the growing stringency of IMO requirements—choosing a future-proof solution is critical. Biological systems are inherently more adaptable, ensuring compliance both today and as further regulations emerge. Operators can remain confident in meeting DNV-type approval, MED certification, and local authority standards.

Bioreactors draw upon robust European engineering and in-depth application experience to deliver dependable, low-maintenance wastewater treatment. By combining advanced biological processes with chemical-free disinfection, our systems support sustainable marine operations and protect the world’s oceans.

• Highly efficient removal of organic contaminants and microplastics
• Fully compliant with IMO and regional maritime standards
• Engineered for longevity, with a comprehensive global service and support network
• Proven performance in ships, offshore installations, and remote locations
  

Learn more about Bioreactors and how biological treatment of wastewater can support sustainable and compliant marine operations.