Worth over $430 billion in goods and services, the maritime industry is one of the most important sectors of the global economy.
It is responsible for the movement of goods, products and passengers by sea, transporting over 90% of trade to all corners of the world. Many nations rely entirely on the continuity of safe, efficient and dependable shipping for their economic prosperity.
While shipping is considered the least environmentally damaging mode of transport per unit of cargo, its sheer scale results in a significant environmental impact. The discharge of pollutants such as oil, chemicals, waste and microplastics into the ocean causes severe harm to marine ecosystems and contributes to the adverse effects of climate change.
It is therefore critical for the maritime industry to adopt innovative marine water solutions, such as advanced filtration technology, to prioritise the welfare of our oceans and those who navigate them.
Advanced Filtration in the Marine Industry
Maritime vessels and cruise liners function as self-contained communities, akin to small villages at sea. As such, they require various filtration systems, similar to those found on land, to uphold the functioning and well-being of the vessel and its passengers. These systems ensure access to clean drinking water, maintain a healthy living environment and manage waste responsibly.
Water Filtration
One of the main essentials humans need to survive is water, and for seafarers and passengers, having fresh, safe drinking water onboard is critical. Up until recently, the main way of providing drinking water onboard was through plastic bottles.
The global environmental impact of single-use plastic is now widely known, with over 10 million tonnes of plastic entering the ocean each year. Methods to eliminate the use of non-essential single-use plastic in the maritime industry are vital to contribute towards environmental sustainability.
Reverse Osmosis
Reverse osmosis is an advanced filtration technique used in onboard desalination plants to convert seawater into fresh, potable water suitable for consumption. During reverse osmosis, seawater is forced through a membrane under high pressure, allowing water molecules to pass through while salt and other contaminants are retained.
One of the most significant advantages of using reverse osmosis for drinking water is its reduction of plastic pollution. By eliminating the need for single-use plastic bottles, reverse osmosis prevents plastic waste from entering the marine environment and harming ecosystems.
Investing in reverse osmosis systems for onboard water treatment can lead to long-term cost savings compared to purchasing and transporting large quantities of bottled water. Once installed, reverse osmosis systems require minimal maintenance and provide a self-sufficient water supply.
Wastewater Management
Wastewater generated on ships comes from various sources, including kitchens, bathrooms, and laundry facilities. This wastewater, categorised as ‘black water’ (from toilets) and ‘grey water’ (from other sources), is collected and stored in dedicated holding tanks onboard the vessel. Before being discharged off the ship, wastewater must be treated to protect marine environments and comply with international maritime regulations set by the International Maritime Organisation (IMO).
Membrane Bioreactors
An innovative technology in wastewater treatment aboard ships is membrane bioreactors (MBRs), which integrates biological treatment with membrane filtration to provide a comprehensive solution. Within an MBR system, wastewater undergoes biological treatment in a bioreactor chamber, where microorganisms break down organic matter. Then, semi-permeable membranes filter out solids, bacteria and contaminants, producing clean effluent suitable for discharge into the sea.
Membrane filtration provides a high level of purification that exceeds regulatory standards and reduces the environmental impact of ship operations. By adopting advanced wastewater treatment technology, ships can operate more sustainably and contribute to cleaner oceans.
Ballast Water Treatment
Ballast water is essential for maintaining ship stability to navigate safely through various sea conditions. By adding weight to the hull, it helps to counterbalance the effects of cargo loading, changes in fuel and water levels, and external forces such as wind and waves.
When a ship is empty or partially loaded, ballast water is pumped into dedicated ballast tanks to increase the weight and improve stability. Conversely, when a ship is fully loaded with cargo, ballast water is discharged to reduce the ship’s weight and draft.
While ballast water is essential for safe and efficient shipping operations, it may pose serious ecological, economic and health risks. When ships take on ballast water in one location and discharge it in another, it unintentionally transports non-native species to new environments, where they can disrupt ecosystems, outcompete native species and degrade habitats, leading to biodiversity loss. Additionally, ballast water may carry harmful pathogens, introducing diseases to marine organisms and posing risks to aquatic wildlife and human health.
Ultraviolet-Based Ballast Water Treatment
Ultraviolet (UV) is an effective and flexible solution for ensuring the safety and environmental sustainability of ballast water management practices onboard ships. These advanced filtration systems use UV radiation to damage the DNA of the microorganisms present in the ballast water, making them unable to reproduce or cause harm to marine ecosystems.
UV-based water treatment systems provide a safe, efficient and environmentally sustainable alternative to chemical-based treatment methods that minimises the impact on marine ecosystems and complies with environmental regulations. While the initial investment in UV-based treatment systems may be higher than other technologies, the long-term cost savings due to reduced chemical usage, lower operational expenses and minimal downtime can be significant.
Final Thoughts
Advanced filtration technologies, such as reverse osmosis, membrane bioreactors, and UV-based treatment systems present innovative solutions to address the environmental challenges posed by maritime operations, ultimately protecting the health of our oceans.
However, there is still much to be done to enhance the maritime industry’s standing as a sustainable and environmentally responsible sector. Ongoing research, innovation, and investment in marine water solutions are essential to further reduce the industry’s environmental footprint and preserve marine ecosystems for future generations.
