The Valmet Wet Electrostatic Precipitator (WESP) controls a wide range of emissions, including particulate matter and black carbon, heavy metals, acid mist, oil mist and visible emissions, for a brighter future.
Black carbon is a component of soot that results from incomplete combustion of fuels. Black carbon particles are ultrafine particles having a diameter of less than 2.5 µm. Therefore they can travel easily to human lungs, where they can cause serious health impact. Black carbon can also absorb sunlight efficiently, and it is considered to be one main contributor to the climate warming.
A combination of a wet SOx scrubber and Valmet WESP brings numerous advantages; The exhaust gas composition after the scrubber is suitable for WESP, and therefore a separate quench is not needed. WESP washwater that contains all impurities captured by the WESP, can also be treated in existing closed loop washwater treatment.
Removal of particulate matter in the WESP is based on strong electrical field created between emitting electrodes and collecting surfaces. When particulates travel through the electric field, they are electrically charged. The charged particles then migrate to the collecting surfaces from where accumulated particles are washed away periodically.
The pilot testing and configuration project was done together with VTT Technical Research Centre of Finland Ltd.
By cutting particulate matter and black carbon emissions by up to 99%, the solution allows a more sustainable operating environment for the shipping industry. It can be used in several kinds of vessels – cruise ships, cargo vessels and others.
Emission regulations will continue to tighten in the coming years. The focus towards the measurement and reduction of particulate matter and black carbon emissions is increasing.
Valmet can offer solutions that can be installed both on newbuilds and operating vessels that still use conventional fuels. This enables shipping companies to significantly reduce particulate matter emissions while continuing normal operations.