mesDRY – The best EGCS solution
Air Pollution In 1997, a new annex was added to the International Convention for the Prevention of Pollution from Ships (MARPOL). The regulations for the Prevention of Air Pollution from Ships (Annex VI) seek to minimize airborne emissions from ships (SOx, NOx, ODS, VOC shipboard incineration) and their contribution to local and global air pollution and environmental problems. Annex VI entered into force on 19 May 2005 and a revised Annex VI with significantly tightened emissions limits was adopted in October 2008 which entered into force on 1 July 2010.
The main type of “bunker” oil for ships is heavy fuel oil, derived as a residue from crude oil distillation. Crude oil contains sulphur which, following combustion in the engine, ends up in ship emissions. Sulphur oxides (SOx) are known to be harmful to human health, causing respiratory symptoms and lung disease. In the atmosphere, SOx can lead to acid rain, which can harm crops, forests and aquatic species, and contributes to the acidification of the oceans.
Cutting Sulphur Oxide Emissions Limiting SOx emissions from ships will improve air quality and protects the environment. IMO regulations to reduce sulphur oxides (SOx) emissions from ships first came into force in 2005, under Annex VI of the International Convention for the Prevention of Pollution from Ships (known as the MARPOL Convention).
Since then, the limits on sulphur oxides have been progressively tightened. From 1 January 2020, the limit for sulphur in fuel oil used on board ships operating outside designated emission control areas will be reduced to 0.50% m/m (mass by mass), unless an exhaust scrubber is installed removing / converting the sulphure before released to atmosphere. This will significantly reduce the amount of sulphur oxides emanating from ships and should have major health and environmental benefits for the world, particularly for populations living close to ports and coasts. mesDRY exhaust scrubber is the answer to comply with the sulphur limit.
mesDRY Exhaust Scrubber
Dry scrubbing technology systems are employed in many industrial applications for power production and incineration, injecting lime or sodium bi-carbonate powder in an appropriate reactor or directly in a bag filter where the reaction takes. The advantages of this dry scrubber process are obvious: • Lowest CAPEX, approx. 10 per cent of a wet scrubber solution. • Simple: Our mesDRY scrubber solution is easy to install during normal vessel service, only few hours of non-engine-operation required. • Lowest OPEX, reasonable absorbent costs and lowest electricity consumption keeps the mesDRY scrubber in advantage compared to a closed-loop wet scrubber. • No scrubber wash water: There is no requirement for sea water or fresh water. There is no wastewater discharge overboard during the regular operation of the scrubber. No monitoring equipment is required. • No cooling requirement, the exhaust remains dry. The injection of mesDRY absorbent for the removal of exhaust gases containing acidic pollutants such as SOx and HCl presents a high efficiency, completely dry alternative for scrubbing
The mesDRY exhaust scrubber utilizes a proprietary blend of nano porous chemical semi dry absorbents consisting primarily of sodium bicarbonate and zeolite catalysts: 2NaHCO3 + SO2 + 1/2O2 → Na2SO4 + 2CO2 + H2O mesDRY absorbent are readily available, we partner with Fuel and Chemical suppliers to supply absorbents to the vessel. In addition, we have tailored a containerized storage solution allowing to store absorbent in a quantity needed to suit your vessel trading pattern. The amount of absorbent needed very much depends on the sulfor content of the heavy fuel oil actually burned. As a rule of thumb, approx. 10 % absorbent is needed for each ton of fuel burned:
The Scrubber consists of an array of pneumatic-hydraulic spray nozzles injecting / vaporizing a proprietary blend of defined nano-porous chemical absorbents consisting primarily of sodium bicarbonate and zeolite catalysts. During the combustion process the sulphur present in the fuel is oxidized to highlyreactive sulphur oxides (SOx). The mesDRY absorbents are highly effective at reacting with the sulfur oxides to form heat stable benign salts. In result, the SOx is removed from the engine exhaust stream.
The approval processes for the mesDRY scrubber is according to Scheme B, including third-party calibrations and maintenance. Compliance will be demonstrated in service by continuous exhaust gas monitoring. The monitoring system is approved by the Administration and the results of that monitoring available to the Administration to verify the compliance as required.
The monitoring system of the EGCS is subject to survey upon installation and upon the Initial, Annual, Intermediate and Renewals Surveys by the Administration. Furthermore, it will remain subject to inspection by port State control in accordance with Regulation 10 of MARPOL Annex VI.
The mesDRY Exhaust Scrubber is designed to remove SOx from the main engine exhaust gas, compliant with Flag State, Classification and Marpol Annex VI regulation 14. At commissioning, the scrubber system is certified to conform to the scope of Marpol Annex VI, regulation 4 and in particular MEPC.259(68). The system is designed to reduce SOx emissions from any HFO sulfur grade down to 0.1 % (ECAS) or 0.5 % (IMO) sulphur.