According to the International Maritime Organization (IMO), the SO2 emission is set to be reduced to an equivalent of 0.5% (w/w) Sulphur content in exhaust gas on ships on Global level in 2020. In Emission Control Areas (ECAs), this limit is 0.1% that entered into force in 2015. All ships and passenger vessels sailing between EU ports have to comply with this level.
Scrubber - Exhaust Gas Treatment
New technologies are coming up in order to reduce emissions and the scrubber technology for marine applications is one of them. The scrubber is an effective system designed to remove SO2 and reduce the harmful particulate emission by the use of water wash the exhaust gas from main, auxiliary and boilers. With the adoption of this scrubber system, vessels sailing in ECA area can continue using low cost heavy fuel oil, but still comply with IMO Sulphur regulations instead of switching to the more expensive distilled fuel with less than 0.1% Sulphur content. The designs of scrubber systems in the market today could be divided into two categories, open and closed types. Power consumption of operating a scrubber system is typically between 1-2% of main engine power.
Open type Scrubber
The open type uses sea water to wash the exhaust gases. The wash water is then treated and discharged back to sea, with the natural chemical composition of the seawater being used to neutralize the results of SO2 removal. Typically, Open seawater systems use 45m3/MW h for scrubbing.
Closed type Scrubber
The closed type uses fresh water in “closed” fresh water circuit that is treated with an alkaline chemical such as caustic soda neutralization and scrubbing. The wash water is re-circulated and the losses is made up with additional freshwater. A small quantity of the wash water is bled off to a treatment plant before discharge to sea. Typically closed freshwater systems have a discharge rate of 0.1- 0.3m3/MW h. The system could also be designed with a holding tank for zero discharge for a certain period.
AVK is making a key contribution to environmental protection by providing high quality butterfly valves and reliable solution services for scrubber systems in various ships where maximum reliability is demanded. A wide range of high performance Wouter Witzel butterfly valves have been supplied to scrubber producers in maritime industry. Our manual and remote controlled butterfly valves with high grade materials can resist to the hostile substances in scrubber systems. The already proven track record of our applied butterfly valves in scrubber systems has shown the high performance, reliability and durability of our products and solutions.
InterApp has built a cooperative partnership with Ecospray Technologies who is specialised in developing innovative high-performance purification systems for regulating the production of waste gas in a variety of industries. For its latest project which involved equipping 30 luxury cruise ships with waste gas purification systems, Ecospray was seeking a reliable technical partner capable of supplying the entire range of butterfly valves they needed. It opted for InterApp, since its products met the project’s ambitious targets in terms of quality and material requirements. InterApp has been providing Ecospray with support since the development phase and supplied everything from one source. The partnership between the two companies was further strengthened during the new project. Additional capacities were also booked in the InterApp plant, which helped to ensure that the project could be successfully concluded on schedule. At the same time, it helped to strengthen ecological values in the cruise ship industry.