Wet Electrostatic Precipitator Technology for Marine Ships: A Powerful Solution for Cleaner Seas
Due to the continued increase in the level of global maritime trade, the shipping industry is under pressure to ensure that its impact on the environment is minimized. Marine engines that use Heavy Fuel Oil (HFO) and Diesel Oil (DO) are still major contributors of the PM and black carbon (BC) emissions- pollutants that have negative impacts on air quality, human health, and global climate. To these problems, the Wet electrostatic precipitator manufacturers and suppliers are now paying more attention to the marine applications and Wet Electrostatic Precipitator (WESP) has become a very useful and future oriented air pollution control system.
Why Emissions from Marine Ships Matter?
The emissions of shipping are not restricted on the open seas. It has been found that the maritime activities can be a source of particulate pollution between 5 and 35% of the local pollution in port cities and coastal areas. Specifically, the PM2.5 and black carbon are the most hazardous types of fine particulates since they enter the respiratory tract and form a connection to cardiovascular and pulmonary diseases. Black carbon is also a key contributor to climate change and contributes to the rapid melting of ice in the delicate area of the Arctic.
The stricter international and regional laws, such as IMO MARPOL Annex VI, Emission Control Areas(ECAs), and high standards of inland waterways have now forced ship operators to implement highly developed technologies which are not merely dry collectors and the conventional exhaust gas purification systems.
What is a Wet Electrostatic Precipitator?
A Wet Electrostatic Precipitator is the most innovative particulate, aerosol, blue haze, acid mist control equipment specifically developed to eliminate very small particles which may be less than one micron, in diameter, in the exhaust. In contrast to dry ESPs which rely on a mechanical rapping or vibration to loosen the dust which has been collected, Wet ESPs depend on spray of water to wash the particle from the collecting electrodes.
This moist cleaning process causes Wet ESPs to be particularly effective in the removal of sticky aerosols, fine particulates and black carbon-pollutants which are not easily removed by conventional systems alone. Wet ESPs are commonly used in the marine sector, either following SOx scrubbers and SCRs, forming an exhaust gas purification system or tail gas treatment system of multiple stages.
Performance of Wet ESPs on Marine Engines
Combined scrubber and Wet ESP systems, when tested on marine diesel engines full-scale, have proven to be exceptionally good at a large operating range. Wet ESP systems with loads between 25% and 100% on the engine resulted in:
1. Removal of particles with efficiency of + 99% under operation on Diesel Oil and Heavy Fuel Oil.
2. Efficiency of black carbon removal is + 96%, which is variable with the type of fuel and engine load.
3. Wash water cleaning efficiencies of around 99% which are safe to be discharged or reused.
These findings demonstrate that Wet ESP technology prove to be much better in comparison with conventional technologies in terms of removal of ultrafine particles and black carbon.
Why Wet ESP technology is Ideal for Marine Application?
Wet Electrostatic Precipitators have a number of advantages that have made them especially appropriate shipboard installations:
1. Very high performance in regards to ultrafine particles as well as black carbon.
2. Modular in shape & Smaller footprints.
3. Less power & water consumption
4. Constant performance in changing engine loads and fuel characteristics.
5. Integration with the current scrubbers, SCR systems.
6. Future compliance with stringent PM and BC emission norms.
These advantages also assist shipowners to enhance performance by voluntary environmental initiatives like the Clean Shipping Index (CSI).
Market Potential and the Road Ahead
The increase in marine emission control solutions is on the rise in the world market with over 100,000 merchant vessels and tens of thousands of inland waterway ships that are in operation across globe. This has given massive market to the Wet Electrostatic Precipitator manufacturers and Wet Electrostatic Precipitator Suppliers who specialize in the control of marine and offshore pollution.
Conclusion
The move towards clean maritime activities will not be reliant on one technology. Nonetheless, WESP- Wet electrostatic precipitator systems are also fast becoming among the most effective applications in regulating the level of particulate matter and black carbon in ship emissions. Wet ESP can be used to fill the gap between the existing regulation and the expected environment by capturing pollutants that are difficult to capture by conventional systems.
