The fuel system

1. Dia 1

mu
S

2. Dia 2

Diesel engines consume Heavy Fuel Oil (HFO),
Marine Diesel Oil (MDO) or Intermediate Fuel Oil (IFO).
Fuel pumps
S
Engine

3. Dia 3

Heavy Fuel Oil is a residual oil that
can be made more suitable for driving
Diesel engines by adding certain
flammable substances.
Marine Diesel Oil (MDO) is a
high-grade fuel of low viscosity.
Modern Diesel engines are run
on Intermediate Fuel Oil (IFO),
a fuel whose grade lies between that of
HFO and MDO.

4. Dia 4

From the Heavy Fuel Oil bunkertank
the preheated fuel is led to the settling tank.
Settling tank
Fuel pumps
Engine

5. Dia 5

In the settling tank water and impurities are
separated from the fuel and drained off.
Settling tank
Drain valve
Fuel pumps
s
Engine

6. Dia 6

From the settling tank the fuel is led through a
heater
to preheat the fuel.
Fuel pumps
Engine

7. Dia 7

From the heater the fuel is led through a separator
(purifier / clarifier)
to purify the fuel.
Fuel pumps
Engine

8. Dia 8

From the separator the fuel enters the
daily service tank for HFO.
Fuel pumps
sound
Engine

9. Dia 9

There are two daily service tanks, so that one
tank may be used while the other is being filled.
Daily service tank
Daily service tank
Fuel pumps
sound
Engine

10. Dia 10

From the daily service tank the fuel is pumped to a
heater
by the low pressure fuel pump
(or “booster pump”).
s
Fuel pumps
Engine

11. Dia 11

From the heater the HFO is passed through a
viscosity regulator
.
Fuel pumps
Engine

12. Dia 12

From the viscosity regulator the fuel is passed through
a fuel strainer
, which filters the fuel.
Fuel pumps
Engine

13. Dia 13

From the fuel strainer the oil is led to the fuel
pumps in the engine.
Fuel pumps
sound
Engine

14. Dia 14

Fuel pumps
Engine

15. Dia 15

After the DO has been pumped up from the bunkertank,
the fuel passes through a purifier
.
Fuel pumps
Engine

16. Dia 16

From the purifier the DO enters the
DO storage tank.
Fuel pumps
s
Engine

17. Dia 17

From the DO service tank the fuel is led to the
high-pressure fuel pumps in the engine.
Fuel pumps
s
Engine

18. Dia 18

A mixing tank is used for a gradual transition from
HFO to DO.
Fuel pumps
sound
Engine
Mixing tank

19. Dia 19

The mixing tank, or “buffer tank”, can hold a
quantity of fuel which will be circulated and led to
the engine.
Fuel pumps
sound
Buffer tank
(Circulating tank)
Engine

20. Dia 20

The hot fuel fumes can escape throughthe air vent
in the mixing tank.
Fuel pumps
s
Air vent
Engine

21. Dia 21

C
P.C. van Kluijven
SHIPPING AND TRANSPORT COLLEGE ROTTERDAM