Exhaust gas cleaning system for the marine industry

Ships are a major source for the emissions of harmful SOx and NOx gases, which are produced by burning fossil fuels and causes pollution. The regulations to protect the marine environment have gradually tightened by the introduction of SOx Emission Control Areas (SECA’s).


As of 1 January 2020 new emission standards are enforced for fuel oil used by ships, in a rule known as IMO 2020. The global sulphur limit dropped from an allowed 3.5% sulphur in marine fuels to 0.5%. This will significantly improve the air quality in many populated coastal and port areas.


  • High temperature flue gas up to 450°C
  • Abrasion between the sealing element and the housing of the butterfly valve
  • The packing must achieve a defined sealing criteria in the exhaust flue gas stream
  • Large size up to DN3400 required

BPG 6445 Damper Gasket

The soft sealing BPG 6445 is especially designed for sealing a butterfly damper. The engineered solution is made of a combination of high-quality glass yarns over braided with a chemical resistant stainless-steel wire to protect the core of the packing and improves the resistance against abrasion. To provide extra stability the product features Aramid reinforced corners. The field proven combination of these features has helped both, OEM customers and end users to comply within the current environmental IMO regulations.


  • High temperature resistance
  • Best available technology supporting IMO and MARPOL compliance
  • Flexible and high level of flange adaptability
  • Available in endless profile or closed rings to meet up with all sizes


Ships may only use low Sulphur fuels, switch to natural gas or alternatively need to be equipped with exhaust gas treatment scrubbers the latter representing a significantly more economical solution in many cases. An Exhaust Gas Cleaning System (EGCS) or scrubber is a piece of equipment for purifying the exhaust gases on a diesel fueled marine vessel. It removes the toxic SOx gas and solid particles from the exhaust gas before it is vented into the atmosphere. There are different designs in the market today, open and closed types. The open type uses sea water to wash the exhaust gases. The alkalinity of the seawater neutralizes the effect of SOx. For fresh water, shallow or sandy water a closed or hybrid system is the preferred. As most of the ships are sailing the oceans, the open type and wet scrubber are the most efficient and effective.


All scrubber systems require a treatment bypass system or butterfly damper for when the ship is operating without the need to use the scrubber. This prevents damage to the scrubber and reduces maintenance. Care needs to be taken to ensure that the scrubber is not causing backpressure to the engine as this could be damaging and will affect NOx reduction systems. Butterfly dampers are fitted with a soft sealing element or packing in order to reduce the leakage rate to a minimum.


BPG 6445 Damper Gasket