WinGD W-X82, Operation Manual

Page: 167 / 548

Operation
0720 − 1/A1
Winterthur Gas & Diesel Ltd.
1/ 5
Fuel Treatment and Fuel System
1. General 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2. Treatment of HFO and Treatment Plant 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3. HFO and Diesel Fuel Separation 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4. Configuration of the Fuel System 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1. General
Heavy fuel oils (HFO), as they are supplied today for use in diesel engines must have
careful treatment, which makes the installation of applicable plant necessary. The
best procedure to remove solid particles and water from fuel is to use
centrifugal separators.
2. Treatment of HFO and Treatment Plant
HFO are contaminated with solid particles and water. If HFO that is dirty or not
sufficiently treated goes into the engine, wear on engine components can occur (e.g.
piston rings, cylinder liners, injection pumps, valves etc). Also, too much sediment can
collect in the combustion spaces.
Sodium in the fuel (which comes from seawater) causes contamination on the pistons
and in the turbocharger. The water must be carefully removed from the fuel.
Settling tanks are used for the first steps of treatment, but their effect is only a coarse
separation to release water from the HFO. The settling tanks must have the sludge
and water, that collects in the bottom of the tank, drained at intervals.
Correctly operated centrifuges that are of the best size and adjustment are used to
get good results during the procedure to clean the fuel. Modern designs mean that is
not necessary to adapt the gravity discs for fuels of different densities.
Modern machines automatically remove the sludge from the centrifuge. For modern
engines designed to burn HFO of the lowest grade, such centrifuges are necessary.
This is applicable when HFO with densities of 991 kg/m
3
and higher and with
viscosities of 700 cSt/50 _ C are used. For more data, see 0710 − 1 Diesel
Engine Fuels.
Homogenizers can improve combustion properties, but cannot remove solid particles
from the fuel. Homogenizers thus, are only auxiliaries in the treatment plant.
Filters hold solid particles of a specified size and shape, but cannot hold back water.
Water will cause the filters to block quickly.
2015-07
Operating Media