2.9.1 Engine Room Bilge System and Bilge Separator
Introduction
The following pumps supply the auxiliary seawater services and, if require, can pump bilges to the bilge tank or overboard in an emergency.
Bilge, Ballast and Fire Pump
No.of sets: 1
Capacity: 160/280 m3/h at 110/45 mth Main Fire Pump
No.of sets: 1
Capacity: 160/280 m3/h at 110/45 mth
Two vertical self-priming pumps are provided with bilge suctions for emergency use. Both pumps are equipped with a vacuum pump driven by the main pump via a friction coupling. When pressure is detected at the discharge of the pump, the vacuum pump drive is disconnected.
Both pumps can pump from the port bilge well using a common direct suction.
or from the following bilge main connections:
Port forward bilge well Starboard forward bilge well Bilge centre
Bilge well aft port Bilge well aft starboard Bilge aft well
Clean bilge tank
Both pumps also take suction from the sea.
Both pumps discharge through a common overboard on the port side.
! CAUTION
The overboard discharge is not to be used for discharging bilges unless under emergency conditions.
Both pumps discharge to the fire and foam system and also to the aft peak tank.
Bilge Water Pump
No.of sets: 1
Capacity: 5m3/h at 3.3 kg/cm2
A bilge water pump is supplied, which can discharge to the sludge shore discharge line and the bilge holding tank. If necessary, the bilge holding tank can be pumped either to the cargo residual tank or ashore when in port.
The bilge water pump will normally discharge through the bilge water separator when at sea.
This pump can take suction from:
The bilge main system The sea
Clean bilge holding tank Bilge Holding Tank
The bilge holding tank collects bilges and drains whilst in port. It is discharged through the separator when at sea. The tank is divided into two parts - one clean and one dirty. A pipe connects the bottom of the dirty tank to the top of the clean bilge tank. The bilge water pump takes suction from the clean side and the sludge pump takes water from the dirty side.
Oily Water Separator
Maker: Blohm & Voss
Type: Turbulo
The Turbulo separator is designed as a gravity separator, where oil is separated in two stages, using the specific gravity characteristics of the oil and water.
Bilge water is drawn into the first stage, where preliminary de-oiling takes place. A coalescer provides treatment in the second stage.
When oil is detected in the separator, it is automatically discharged to the sludge tank by means of a solenoid valve. A heater in the upper part of the separator assists separation.
If the outlet from the separator contains an excessive oil content, it is recircu-lated back to the bilge holding tank by means of the automatic three-way valve.
High level alarms are fitted in each bilge well.
! CAUTION
The O.W.S is designed to separate oil from water not water from oil. i.e. if the discharge from the O.W.S. contains excessive amounts of oil it will render the equipment useless and result in unnecessary maintenance.
Procedure for the Operation of Pumping Bilges to the Holding Tank a) Check that the strainers and strum boxes are clean.
b) Open one of the following suction valves.
Description Valve
Port forward bilge well QD21
Starboard forward bilge well QD22
Bilge centre QD59
Bilge well aft port. QD14
Bilge well aft starboard QD15
Bilge aft well. QD4
Clean bilge tank. QD91
c) Open the bilge water pump suction valve from the bilge main QD9.
d) Open the bilge water pump discharge QD17.
e) Open the bilge water pump discharge to the holding tank QD18.
f) Start the bilge water pump.
The pump can be primed by temporarily opening the pump sea suction valves QD10 and QD12.
g) Before the bilge well in use loses suction, open the valve on another well and close the one in use.
Bilge pumping should be monitored constantly, as running dry will damage the pump.
h) When all wells are dry, stop the pump and close all valves.
Illustration 2.9.3a Bosun Store and Chain Locker Bilge System
Forward Deck
Forward Deck Under Forward Deck
Bosuns Store Port Chain Locker
Port Hawse Pipe
Starboard Hawse
pipe Starboard
Chain Locker To Bow
Thruster Room
Bow Thruster Room Bilge From
Main Deck Fire Main
Key
Deck Fire Water
Bilge JX25
JX24
JX36 JX35
JX37
JX38 JX27 JX28
JX34 JX30
JX26
JX31
JX32 JX72
JX71
JX29
JX31
Procedure for the Operation of Discharging the Clean Bilge Tank through the O.W.S
a) Open the following valves.
Description Valve
Inlet Valve to O.W.S. from:
Bilge Holding Tank QD91
Bilge water pump suction QD8
Discharge valve from O.W.S. pump QD77
Overboard Discharge QD3
b) Supply power to the O.W.S.
c) Check the oil content monitor by passing fresh water through the sensor.
d) Check the reading and shut off the fresh water supply.
.
Pumping sea water through the O.W.S. and then changing the suction to the bilge holding tank can check the operation.
The clean exit water will be discharged overboard. Oil contamination of 15 ppm or over will sound an alarm and automatically recirculate the discharge back to the holding tank, through the 3-way valve QD76, until the water is clean enough to discharge overboard. Any oil collected at the top of the O.W.S.
will be discharged to the sludge tank.
e) After completion, stop the pump and close all valves.
Any oil/water remaining can be discharged by the bilge pump to the sludge discharge line by opening valve QD7. It can be pumped ashore or to the cargo residual tank by means of a portable hose.
Main Cooling Sea Water Pump
The No.1 main cooling water pump can also pump out the bilge via the emergency bilge suction valve, which is connected directly to the pump suction.
WARNING
Before any bilges are pumped directly overboard, it must first be ensured that no local or international anti-pollution regulations will be contravened except where safety of the ship or personnel is involved.
In Port or Coastal Waters
Any bilges which require pumping, when in port should only be pumped to the bilge holding tank using the engine room bilge transfer pump. The contents of the bilge holding tank can then be processed when the vessel is in open water.
At Sea
The engine room bilges and the contents of the bilge holding tank should only be pumped overboard through the oily water separator system. Any oil will then be separated out and discharged to the oily bilge tank and the clean water will be discharged overboard if it is clean enough. If it is contaminated with oil, it will be diverted automatically back to the bilge holding tank.
2.9.2 Pump Room Bilge System
A bilge eductor driven by sea water from the fire main is used to drain the ballast pump room bilges. There are two suctions Those being the port and starboard pump room bilge suctions. The two pumproom bilge suctions are normally open, in case flooding of the pump room makes the valves inaccessi-ble.
High level alarms are fitted port and starboard.
The bilges are normally pumped to the port slop tank.
Procedure for Draining the Pump Room Bilges using the Bilge Eductor Set up the valves as in the following table:
Position Valve Description Valve
Normally Open Port Bilge Suction AD42
Normally Open Starboard Bilge Suction AD41
Open Discharge to Port Slop Tank AD45
Open Eductor Sea Water Inlet AD60 & AD37 Close AD60 followed by all other valves when suction is lost.
2.9.3 Bosun Store and Chain Locker Bilge System
Three bilge eductors each with a capacity of 8m3/h and driven by sea water from the fire main, are provided for the drainage of the bosun’s store, chain lockers and thruster room. Each suction point is equipped with a suction filter and non-return valve.
High level alarms are fitted in the bosun's store and thruster room.
Procedure for the Operation of the Forward Bilge Systems
a) Ensure that the suction strainers are clean and the cover joint is correctly fitted.
b) Start the fire bilge and ballast pump and pressurise the fire main.
c) Open the appropriate overboard discharge valve.
d) Open the appropriate eductor suction valves.
e) Open the appropriate eductor seawater supply valve.
f) On completion, close all the above valves.
QB10
Illustration 2.10.1a Starting Air System.
No.1
To Scupper To Scupper
To Scupper To Scupper
To Scupper
To General Service and Control Air
Oil/Water Separator
PS Upper Deck
Air
LT Cooling Water
Key
Funnel Top
Control Air
RK12 RK3 RK2 RK1
RK4
Alarm For P/R Safe