Tier III NOx limits apply in Emission Control Areas. One of the leading solutions for meeting them is Exhaust Gas Recirculation, or EGR. Integral to the engine, EGR is supported by Alfa Laval PureNOx, a centrifugal separation technology for EGR water cleaning. EGR has always been simple, compact and cost-effective. But with the latest PureNOx developments, those advantages are even greater. PureNOx systems are now optimized according to the fuel sulphur level: low-sulphur (LS) or high-sulphur (HS). This reflects the global sulphur cap – and Alfa Laval’s commitment to providing optimal solutions for all fuel choices. If the vessel uses low-sulphur fuel, PureNOx LS cleans only the EGR bleed-off water. This is water that accumulates in the EGR system, comprising combustion condensate and water from the EGR process. To maintain equilibrium, excess water overflows from the buffer tank into the drain tank for treatment by PureNOx LS. To meet MEPC requirements, PureNOx LS cleans this bleed off-to 15 ppm oil in water before it’s discharged overboard. If the vessel uses high-sulphur fuel in combination with a scrubber, PureNOx HS protects the engine by cleaning the EGR process water. An initial filter stage removes process water contaminants. Then, the separator removes heavier particles from the bleed-off water, which is discharged through the scrubber system. Because the systems are optimized for the type of cleaning they perform, each system’s design is streamlined. In fact, the separator module is 50% smaller than before. But the savings don’t stop there. Both systems also support Eco EGR, an engine mode for use at Tier II. Eco EGR allows engine trimming for maximum fuel efficiency, which can save up to 5 grams of fuel per kWh. But the process demands continuous water treatment and only PureNOx systems have been tested and proven in continuous use. With today’s PureNOx systems, EGR can be more cost-effective than ever before. To learn how optimized PureNOx technology can make the difference for your vessel, visit the PureNOx website.