For each and every boat, whether a cruise ship or not, on-board waste management is a real problem. Among the waste produced on board, wastewater represents in average a daily volume of 1900 m3 for a middle-sized cruise-ship. In order to limit discharges into the sea (only permitted at a certain distance from the shore), regulation requires at least a dedicated storage tank or at best, an on-board wastewater treatment facility. Similarly, ports also have the obligation to have wastewater reception facilities.
As part of the Port of Marseille Smart Port Challenge 2, EDF and ACQUA.ecologie developed a solution around 3 objectives: minimizing wastewater discharges into the sea, maximizing the low carbon energy recovery of wastewater and reducing the overall environmental impact of wastewater treatment. It is a modular solution that combines a membrane ultrafiltration system with a heat recovery system and thus makes it possible to produce reusable water and heat from wastewater generated by cruise ships.
100% of the wastewater can therefore be recycled and reused for any non-potable use, such as cleaning water, irrigation water or for flushing toilets. From an energy point of view, 50% of the thermal energy of the wastewater can be reused on board for preheating of domestic hot water. Overall, this solution reduces water consumption on board by 60% and the associated energy bill and CO2 emissions by 40%.
However, wastewater in a large seaport is not limited to ocean-going cruise ships. A similar solution has therefore been devised for smaller ships, ships at berth or undergoing ship repair and operating buildings. This solution is based on a wastewater collection system using a mobile hydrogen barge combined with a fixed system underground wastewater recycling & thermal recovery system.