Marine Exhaust Gas Boilers

Eliminate fouling on exhaust gas boilers downstream of the engine

Marine Exhaust Gas Boilers

Exhaust gas boilers are an integral part of modern day vessels.

Since the need for steam is minimal on these ships, they are often the only source of steam generation while the ships are on passage at sea. Small compact boilers serve as steam accumulators and are fired only on need. Therefore, the efficiency and integrity of the exhaust gas boilers are essential for continued efficient operation.

Managing of fouling in exhaust gas boilers is an issue ships engineers and fleet managers have had to contend with over time. In order to manage the fouling, ship’s crew plan and clean the exhaust gas boiler every three or four months when the opportunity presents itself.

Cleaning entails the use of water which will have turned acidic due to the presence of SO3. This has then to be stored in ships steel bilge tanks which then become susceptible to corrosion attack.

Therma-Chem Solution

Therma-Chem MB9 is a well proven solution to manage fouling in economizers. Injected as a fine spray into the exhaust gas stream while the main engine is in operation, the chemical vaporises and expands to form a mist which flows into the economizer and works by:

  • Oxidising unburnt fuel and lubes
  • Converting existing fouling into a dry, powdery substance
  • Reacting with acids to prevent corrosion

This eliminates the need to water wash the economizers and, therefore, there are no subsequent effluent disposal costs. Using Therma-Chem MB9 will therefore improve operating efficiency, eliminate corrosion and prevent unneccesary manual cleaning of the economizer.


Dosing can be on a regular basis or on requirement when differential pressures across the economiser reaches predetermined levels.