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Catalytic Fines- Alumina/Silica

  • They are hard, abrasive particles.
  • It is also possible to contaminate a clean marine residual fuel oil with catalyst particles during transport. For example, if steamship fuel (frequently containing catalyst particles) has been transported by barge prior to moving a clean heavy fuel oil for a diesel powered ship, the barge bottom sediment will be mixed with the clean fuel oil and will contaminate it.
  • Cat-fines are generally small, very hard, and quite abrasive to pumps, atomizers, piston rings and liners.
  • (30 ppm) of alumina in the bunkered fuel oil is the upper limit for successful treatment and engine operation. 
  • The average particle size, as well as the concentration, greatly impacts the wear rate of engine components. 
  • Small sized catalyst particles (1-10) micron range typically cause accelerated wear in injection pumps and injectors and only moderate increases in cylinder assembly wear, such as piston rings, piston grooves, and liners. 
  • The larger sized catalyst particles, in the ten to seventy (10-70) micron range, typically causes very accelerated wear rates in the cylinder assembly area. Also on injection pump inlet valves, exhaust valve seating areas, and turbocharger turbine blading. 


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