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The Good, the Bad and the Effluent

Emissions get all the attention, but wastewater’s a problem too.

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By A.J. Pessa 04-10-2020 11:55:12

(Article originally published in Nov/Dec 2019 edition.)

In a world determined to become environmentally sustainable, the maritime sector has thus far prioritized technology that reduces SOx and NOx emissions. However, even a cursory look at water treatment and effluent reveals environmental issues that are equally worthy of consideration and concern. 

For example, 2019 brought to light concerns related to open-loop scrubbers. The inconvenient observation is that open-loop scrubber systems may effectively remove harmful materials from the air only to dump them into the ocean as sludge. A handful of nation states has updated regulations to prohibit use of these types of exhaust gas cleaning systems within specific territorial waters.

If bans on open-loop scrubbers continue, it will be bad news for shippers who’ve invested in this technology in response to IMO 2020. Reportedly, about half the cruise ship market has adopted scrubber systems instead of switching to low-sulfur fuel. 

It’s not certain how scrubber effluent concerns will be rectified in 2020, but it’s becoming increasingly clear that innovation toward environmental sustainability will be a step-by-step process and that emissions and effluent must be considered together. 

In 2020 there will likely be continued debate over scrubber effluent and a variety of other wastewater issues. There’s demand among some experts for establishment of better MARPOL definitions and regulations for grey water. The use of chlorine in effluent disinfectant processes is also being challenged. Likewise, standards and innovations related to eutrophication (excessive nutrients in water, causing algae, fish kills, etc.) are increasingly in focus. 

While progress toward environmental sustainability is made gradually and collectively, there are key players and technologies available to achieve the maritime industry’s goals. 

Cutting-Edge Technology

Focused on everything related to water, Veolia is traditionally involved with potable water preparation through reverse osmosis systems, currently in use on Carnival Cruise ships. It also develops water recovery systems that improve efficiency including a system that harvests condensation from air conditioners and transfers it for use as technical water in other shipboard applications.

Its revamped sewage treatment system is based on a submerged membrane reactor (MBR) that has been a dependable and low-maintenance-cost solution to the cruise industry for about ten years. The CS-MBR advanced water treatment system is designed to address IMO MEPC 227 (64), including Chapter 4.2 for nitrogen and phosphorous removal within special areas, thereby mitigating eutrophication. It’s also exceptional for savings on power consumption. 

Valentin Kirsch of Veolia says the CS-MBR offers the lowest power consumption rating per cubic meter of water and is most attractive to cruise ships. According to Valentin, cruise ship operators are more likely than merchant vessel owners to invest in high-end technology due to the longer lifecycle of cruise ships and the greater focus on energy efficiency and quality effluent in cruise ship standards. 

With a lifecycle approximately double that of a merchant vessel, greater economies of scale can be realized when a cruise ship operator invests in technology that improves efficiency, has lower maintenance costs and keeps them ahead of evolving environmental standards. 

“For the cruise ship industry,” says Valentin, “energy efficiency is very important. Effluent quality is also very important.”

In other high-tech developments, Veolia is preparing to launch shipboard use of the AQUAVISTA™ plant intelligent software. Currently, this modular intelligent software is available on land-based water treatment plants and provides continuous monitoring of resource consumption levels, flow and circuit output and processed water purity levels. The information is displayed through a portal and via a series of customizable dashboards. 

Implementation of AQUAVISTA™ on ships means data from water treatment processes will be continuously logged and monitored from a shoreside office. Remote control of the water treatment equipment is not possible due to regulations. However, remote monitoring of a vessel by wastewater specialists provides peace of mind and eliminates unnecessary downtime by recognizing problems in advance, prompting routine maintenance and optimizing logistics for delivery of parts. 

The security provided by a system like AQUAVISTA™ is especially valuable for the delicate biological processes at play in sewage treatment. If a problem in the system is not detected and the biological process is lost, weeks of downtime are necessary to regrow it. Moreover, cruise ships typically don’t have wastewater experts on board, and the overview of an expert ashore is very valuable. 

Royal Flush

Founded in 1982 in South Florida, Headhunter quickly grew as a result of the notoriety of its reliable products and customer service. Its first patented product is known today as the Royal Flush Classic Toilet, and it continues to demonstrate the legacy of Headhunter’s engineering and humor in naming products.

From a humble beginning providing plumbing products to the local yachting community, Headhunter is now internationally relied upon for sanitation products that work. As stated on its website, “From Turkey to Taiwan, New Zealand to New England, from the Maldives to Maine, Chile to Finland, somebody is riding a Royal Flush!”

Headhunter has a solid foothold in the small cruise ship market with the TIDALWAVE HMX wastewater treatment system being the product of choice for companies like UnCruise, Galapagos Cruises, Phillips Cruises and the Metropolitan Touring Fleet. The TIDALWAVE HMX system uses flocculent settling, chemical oxidation, hydro-maceration and patented cross-flow separation technology to thoroughly destroy influent biomass. It’s all done without the need for an additional sludge retention tank onboard. These systems are popular because they’re reliable and have low maintenance costs. 

Headhunter Vice President Mark Mellinger says they’re currently building two new TIDALWAVE HMXs for UnCruise’s Wilderness Explorer. Meanwhile, Headhunter sanitation systems, water pressure systems, hoses, pumps and toilets by the dozens are in high demand in the cruise ship industry. 

In addition to reliable sewage treatment systems and toilets, the company is a leader in water pumps. The MACH 5 pump dominates the market for vessels 48’ to 120’ LOA. For smaller boats, there’s the XCALIBER, and larger vessels of 120’ to 180’ LOA utilize the AQUABOX. Mellinger says the AQUABOX will soon be fitted to Fugro’s Fugro Explorer. 

Headhunter also offers chemical and biological consumables. For example, REVEILLE is a fantastic consumable for the treatment of smelly water, including grey water, black water and sea water. EFFERSAN, a stable, non-bleaching tablet disinfectant, is used for freshwater preparation in disaster-stricken areas. 

From Land to Sea

Masters of the simple, robust and virtually indestructible, Scienco/FAST is positioned to offer advanced water treatment solutions to cruise ships in response to changing environmental standards. Its MarineFAST sewage treatment system, available in a variety of sizes, is considered “the easy way to deal with sludge.” Processing black and grey water, all MarineFAST systems are certified to USCG and IMO regulations. 

Scienco/FAST is a subsidiary of BioMicrobics Inc., a land-based water treatment company. Combined, the two companies have 45,000 water treatment installations in 60 countries. They also have experience in retrofit installations aboard vessels, custom-tailoring their products for different hull spaces. 

MarineFAST can be incorporated with gravity or vacuum-fed collection models. It’s designed to be an economical and reliable option for smaller vessels. The fixed media and no-moving-parts design is self-regulating and handles surges and overloads without the need for manual cleaning. Scienco/Fast says that MarineFAST does this better than any other biological treatment system. 

Digital Future

While it’s uncertain whether international effluent standards will receive attention from the IMO in coming years, innovation related to advanced water treatment efficiency will continue to be in demand. 

Current trends indicate that fixed media systems will be favored. The theory is that bacteria lives in a more productive way when it’s fixed, not free-floating, because this is most similar to the natural environment and behavior of bacteria. Improvements to membrane technology will allow for more efficient molecular diffusion, separating water from material without clogging and with less air pressure needed. 

Systems that offer more control over the biological process will prevent overgrowth and maximize efficiency by keeping the most mature and productive bacteria at the forefront with infantile bacteria nurtured but not slowing down the process.  

The future will bring further integration of digital systems and water treatment. Increasingly, every part of a ship can be digitized, monitored by sensors for data mining and processing. There will soon be more marine water systems that can be controlled and monitored by human machine interfaces, and perhaps in the more distant future technology and regulations will allow for remotely (shoreside) operated water systems. – MarEx  

Ship’s officer Joey Pessa writes regularly for the magazine.

The opinions expressed herein are the author's and not necessarily those of The Maritime Executive.