A basic aspect in an exhaust system of a ship is the heat emission. This heat can feed a wide spectrum of applications, but may also be experienced as a nuisance.
In naval vessels, heat outside the ship is increasingly seen as an undesirable aspect. In order to suppress this aspect, Discom has done research on relatively simple methods using water injection to cool the exhaust gases. In naval terms this is also called IR suppression or infrared suppression.
For workboats this is different. Here, water injection also provides a solution but not by suppressing the infrared signature. In this example full view on the working deck from the bridge is of great value. Also emission requirements are becoming increasingly important for this segment, which could be considered eg NOx reduction.
For both types of ships, Discom developed the right solution including emission control: the ultimate water-injected exhaust system, which uses generally sea water.
There are several possibilities for blowing off the exhaust gas and water. When it is desired to keep the water and the gas separated from each other, this can be done by for example, a water separator. This water separator may also be seen as a second silencer, where the cooling has a positive effect on the noise reduction.
Because the exhaust system is a key component of the propulsion chain of the ship, the water injected design is always prepared to run dry or hot, with no damage to the vessel.
[mappress] Naval Today Staff,October 23, 2012; Image: Discom