Keep it Clean

It’s a fact so commonly known that it’s almost a cliché – that the seas occupy over two-thirds of the earth’s surface. As the ubiquitous medium across which vessels pursue their commercial objectives, the abundance of seawater makes it particularly easy to overlook as a vital resource. But its functionality on board ships is so pervasive that salt water has become critical for daily activities.

As Samuel Taylor Coleridge astutely observed, sailors of yore suffered no shortage of water, just the potable type. And while rum was – and arguably (maybe) still is – a fantastic means of boosting morale, it did little to support longevity and health. It wasn’t until the 18th century that inventors had created distillation plants that converted brine into distilled water, a technology that was universal until the late 20th century when reverse-osmosis systems came into wide use.

What both approaches have in common is the salt water media, further demonstrating its functionality in multiple shipboard applications. Likewise, with the evolution of propulsion methods and pumping equipment and overall improvements in design and materials, seawater replaced more permanent ballasting methods and became the vehicle for vastly improved hygiene and sanitation on board.

Wastewater Discharges

What’s taken on board must eventually be discharged.

Improved conditions and convenience onboard ocean-going ships did not come without its drawbacks. With the increasing environmental awareness of the late 20th century, “The maritime industry was increasingly held responsible for the emission of pollutants in the environment,” explains Benjamin Jeuthe, Head of Marketing for Germany’s Hamann AG, a leading manufacturer of sewage treatment plants for the marine industry.

Significant penalties accompanied severe restrictions on what could be discharged from vessels and where. The most important of these regulations is, of course, the International Convention for the Prevention of Pollution from Ships (a.k.a., MARPOL). Although originating from a series of tanker accidents, MARPOL focuses on several specific environmental threats.

Sewage was perhaps the most egregious contaminant of ports and waterways, and ships were an obvious source. As the maritime industry grew in size along with ever-larger vessels, the more obvious this pollution became. Hamann, as a pioneer in the industry, realized that addressing this issue was what Jeuthe calls “an obligation of the maritime industry towards society as a whole.” Since 1972, the company has supplied the industry with sewage-specific treatment equipment that not only complies with applicable regulations but, above all, respects the marine environment.

Wastewater treatment systems have been in marine applications for several decades now and are periodically subject to changing and updated regulatory requirements. As regulatory efforts encompass more types of discharge from vessels, companies providing treatment services and equipment continue to deliver innovative solutions. 

Norwegian-based Scanship, a subsidiary of VOW ASA, started with comprehensive advanced wastewater purification (AWP) systems in the early 2000s. Since then, it’s set new standards of efficiency, reducing up to 90 percent of wastewater contaminants – among the very few suppliers achieving such results, according to Bjorn Bache, VOW’s Chief Commercial Officer.

Ballast Water Discharges

A more recent development was the recognition that vessels transiting long distances inevitably introduced foreign organisms through their ballast water discharges, wreaking havoc on ecosystems.  As a result, international regulatory bodies have focused more recent efforts on limiting ballast water exchange in order to mitigate the threat of invasive species.

Current guidelines call for vessels to undertake ballasting and deballasting at least 200 nautical miles from port and in water depths of at least 200 meters. While vessels don’t have to deviate from established routes in order to specifically meet these criteria, the guidelines still impact transit times and stability concerns and present operational restrictions.

These concerns resulted in the development of ballast water management/treatment systems (BWMS/BWTS), providing a mechanism by which biological contaminants in ballast water can be eliminated and creating options for vessels regardless of location.

Among the systems Damen Green Solutions offers is a modular, plug-and-play BWTS that’s the result of a partnership with Erma First. “Our client needed a temporary ballast water treatment solution,” explains Damen Sales Manager Rutger van Dam. The oneTANK system uses a chemical solution that is neutralized after use and is the world’s smallest BWTS system.

“For owners working with smaller vessels that aren’t dependent on frequent ballast operations,” he adds, “oneTANK is a great solution, portable enough to be housed in a twenty-foot container with straightforward installation and removal.”

Another unique, but non-chemical approach to BWTS is Purestream™ from Atlantium Technologies, a global leader in water treatment. “The introduction of UV treatment was a significant milestone for the industry,” states Atlantium CTO Ytzhak Rozenberg. “We took it one step further with the introduction of our Hydro-Optic™ UV technology.” 

Ultraviolet (UV) light has long been used in potable water applications. By applying it during ballasting, Purestream upends the ballasting/deballasting process, adding flexibility to when and where such activities can take place and making the entire process more efficient.

Paradigm Shift

Equipment and service providers see a paradigm shift among their clients and within the industry itself.  According to VOW’s Bache, stricter regulation is forcing equipment manufacturers to not only comply with the rules but to anticipate what comes next. The focus is not strictly on meeting the letter of the law but also on protecting the ocean and environment, which requires disruptive thinking.

The once cavalier approach to seawater usage is undergoing a shift by necessity, and not just because of regulatory restrictions. Given increased public scrutiny, customers are demanding higher performance and quality from their vendors. “We put a lot of effort into ensuring that our customers can meet the required standards with our systems in day-to-day operation,” states Hamann’s Jeuthe. “That is often a completely different matter than obtaining type certification from the authorities.”

Customers see the impact the maritime industry is having on the environment. “Pollution to our oceans is being better controlled and awareness is increased among both passengers and operators,” says Bache, in a nod to the increased attention toward environmental, social and governance (ESG) issues. As such, environmental stewardship not only assures compliance with applicable laws but becomes critical in developing a positive reputation and drawing in new customers.

Rising Digital Tide

The entire maritime industry is fixated on the evolution toward carbon-neutral operation and improving overall efficiency. Compared to net-zero campaigns shoreside, wastewater treatment technology is evolving along the very same path but with a focus both below the waterline and above the stacks. The ultimate goal is not only zero emissions but zero discharges.

With this objective in mind, VOW is pursuing technologies that replace traditional incinerators. Using proprietary hydrolysis and pyrolysis processes, its Scanship subsidiary is developing a low-carbon method for handling the sludge generated from wastewater, food waste and garbage disposal. Recycling and recirculating allow for extracted water to be further treated in the connected subsystems while the resultant dry biomass can be converted to green energy and biochar for a myriad of applications both onboard and shoreside.

Hamann’s Jeuthe points to the rising digital tide as a further driver of wastewater treatment technology: “More efficiency will go hand-in-hand with more complex process engineering as well as increased sensor technology, automation, connectivity and subsystem integration.” He expresses confidence in Hamann’s readiness for a new future, “We are already building up human resources, know-how and production capabilities to drive this increased digitalization.”

For its part, Atlantium’s Rozenberg points to his company’s history of successful innovation, global network of service providers and thousands of existing installations: “We’re focused on continuing to deliver optimal performance and ROI and are always looking forward to meeting the unique demands of the next challenge.”

Wiser Stewardship

The earth’s massive volume of seawater is increasingly viewed as an irreplaceable ecosystem, and the  maritime industry – recognizing its essential responsibility – is working diligently to shed its negative environmental characterization, whether deserved or not.

Alongside advances in fuels and energy storage, wastewater treatment systems play a critical role in reconfirming the industry’s perspective and reputation as the most efficient means of transport per ton of cargo. Using current and developing water treatment technologies, it will have a significant and beneficial impact on the environment as well as on other industries. – MarEx

Frequent contributor Chad Fuhrmann is the founder and owner of REvolution Consulting X Engineering.