Hamann offers sewage treatment technology based on dissolved air floatation (DAF) combined with two interconnected moving bed bio-reactor (MBBR) modules for such MARPOL special areas as the Baltic Sea and Alaska, according to Benjamin Jeuthe, head of marketing and communications. The final step of the treatment process in all the systems is the deactivation of E. coli microbes by UV radiation.

He explained that the modular design allows for a small footprint and flexible installation. Rather than being one big unit, he said, the system is designed as separate modules that can be installed separately, even on different decks.

By combining modules of different sizes, Hamann’s system can be scaled to the required capacity. Also with multiple smaller modules and redundant modules for each process step, the system will continue to operate at reduced capacity even if one module should fail, said Jeuthe.

And with no membranes or filters that have to be cleaned, serviced and replaced, he said the system requires little maintenance and is easy to operate.

As an example of an installation, Jeuthe said that a cruise ship with some 6,000 people aboard would produce 225 liters of combined black and gray water per person, or 1,395,000 liters (358,750 gallons), per day. For a ship of that size, Hamann would specify it’s HL-CONT Plus OceanCruise system with DAF technology and MBBR. It has a treatment capacity of 60,000 liters per hour.

“The end result is 97 percent treated water and 3 percent sludge,” he added. “Our systems are designed for a combined intake of gray and black water in the ratio of approximately 4 to 1.

“The proportion of water in the sludge is reduced to the extent that it is still pumpable. After fully automated separation, the sludge is pumped into a holding tank. There are various ways of disposing of the sludge, which are coordinated with the operator,” Jeuthe explained.