February 25, 2010
ABS verifies effectiveness of CSNOx exhaust gas treatment system
An exhaust gas treatment system that uses water with increased alkalinity is showing impressive results. Singapore-based Ecospec Global Technology Pte Ltd. reports that ABS issued a statement on February 8, 2010 verifying the results of sulfur dioxide (SO2), carbon dioxide (CO2) and nitrogen oxide (NOx) removal from the emissions of a trading 100,000 dwt Aframax tanker installed with the Ecospec CSNOx gas abatement system.
In the first load point verifications, part of the ongoing IMO Type Approval certification process, conducted during the last week of January 2010 onboard the Aframax, at 50% gas load (equivalent to approximately 5 MW engine output), ABS issued a Statement of Fact on the performance of CSNOx system showing showing reductions of 98.6%-98.9% in SO2, 76.5%-77.1% in CO2 and 64.5%-66.2% in NOx burning 380 cSt fuel with a 3.64 percent sulfur content.
In the CSNOx system freshwater or seawater is first fed into an Ultra-Low Frequency Electrolysis System (ULFELS) to make it alkaline and ready for scrubbing. (Seawater goes through an additional antifouling treatment before the ULFELS tank to control microbial growth in the system.) The alkaline water is then pumped through the exhaust stack to scrub the flue gas. Ecospec says that CSNOx-treated water is highly reactive and effective in removing CO2, SO2 and NOx through absorption. The removed pollutants are converted into harmless substances found naturally in the water. After scrubbing, the scrubbed water may pass through a solid-liquid separator to remove solid particles. The water recovered will then undergo an integrated treatment to meet the discharge water standard. If the water supply is limited, the scrubbed water can be further treated and recycled back to the scrubbing process, reducing the amount used.
The Singapore-registered oil tanker on which the load point verification was carried out is owned and managed by Tanker Pacific and was sailing from Singapore to the Middle East via Sri Lanka.
Ecospec says the removal efficiencies of the CSNOx system allow vessels installed with the system to continue using normal heavy fuel and yet meet the 0.1% sulfur content required by an EU Directive effective from January 1, 2010. In other words, says Ecospec, there is no need for vessel owners to convert to distillate fuel or modifying the fuel system for switching to distillate.
The removal efficiency for NOx is the absolute reduction percentage. After translating this removal efficiency into Tier 1, 2 or 3 NOx emission requirements,says Ecospec, the CSNOx system is able to remove NOx to levels that enable vessels installed with it to meet even the strictest Tier 3 requirement. The company also says that , apart from meeting the SO2 and NOx requirements, there is no other cost effective system currently available to remove CO2 at the rate the CSNOx system is capable of.
Mr. Chew Hwee Hong, Founder and Managing Director of Ecospec, says: "The shipping community is thrilled with the results. CSNOx is extremely efficient in removing CO2, SO2 and NOx. Of significance is also the wash water quality, which met all IMO requirements with most parameters surpassing the strict criteria by a large margin. ABS verifications also underscore the fact that CSNOx is the world's first proven commercially viable solution that can effectively reduce the hotly debated GHG and pollutants all in one system."