La integral de Lebesgue

Issue: 1

Hydraulic Room

Key

General Service Air Instrument Air Hydraulic Station Spraying Nozzles Spraying Nozzles Spraying Nozzles Vent Mast No.2 Spraying Nozzles Forcinging Vaporiser Main Vaporiser H.D. Compressor Gas Heaters L.D. Compressor Glycol Heaters Stbd. Bunker Crane Port Bunker Crane Main Deck Ladder Hoist Main Deck Ladder Hoist To Suez Canal Search Light To Forecastle Deck

Weed Blow for Emergency Fire Pump Sea Water Box

De-watering Pump No.3 Secondary Barrier

De-watering Pump No.2 Secondary Barrier

De-watering Pump No.1 Secondary Barrier De-watering Pump No.4

Secondary Barrier Supply from Engine Room Barrier Connection Water Trap and Drain Manifold Manifold

Illustration 2.13.1a Deck Instrument and General Service Air Systems

2.13 Air Systems

2.13.1 General Service and Control Air System

The general service air is supplied by a single 240m3_{/h at}

8.5bar compressor XA/226 mounted in the engine room with a 3m3_{receiver X/A237 in line.}

The control instrumentation air is supplied by 2 x 290m3_/h

at 8.5bar compressors XA/224A & B mounted in the

engine room. The compressors discharge into a 5m3

receiver, before passing into the distribution line via an automatic refrigeration and absorption dryer unit. Instrumentation compressors are arranged for one to be in the duty run mode and the other to be in a standby condition. For emergency use there is a cross over connection between the general service and instrumentation before and after the air receivers. The operation and control of both the general service and instrumentation air compressors and the dryer unit is from the engine room.

The general service air supplies the following deck

equipment: bunker crane port and starboard,

accommodation ladder hoists port and starboard and secondary space dewatering pumps mounted in secondary barrier well. A number of outlets are arranged around the deck of the ship to facilitate the use of pneumatic power tools etc. At the forecastle there is a facility for connection of the Suez canal searchlight, there is also a line leading down to the emergency fire pump sea chest for weed blowing. At the starboard aft corner of the accommodation there is a water trap to enable all water to be drained from the system.

The control and instrumentation air supplies the following equipment on deck: stripping excess flow regulating valve nozzles at each cargo tank, the supply of air into the compressor room for the control of the HD and LD compressors, vaporisers and heater systems, for the glycol heaters in the motor room and all glycol system regulating valves for the cofferdam heating. The system also operates the No. 2 vent mast riser fire smothering system with the release of nitrogen.

2.13 Air Systems - Page 1 Issue: 1

2.14.1a Deck Steam System Issue: 1 HC LC PIC HC LC PIC T T OdA Key Steam Condensate Control Air Sea Water Instrument YA/5142

Drip Tray Heating for Manifold From Engine Room Steam Supply Return to Observation Drain Tank via Drains Cooler in Engine Room Vent Gas Heater Cofferdam Heater Main Vaporiser YA/ 5500B VA/ 060VR VA/ 040VD SP/ 015SC SP/ 016VD VA/ 041VD VA/ 040VD VA/ 041VD SP/ 001VD YA/ 5500A VA/ 060VR VA/ 061VR VA/ 042VD SP/ 015SC SP/ 017VD VA/ 043VD VA/ 042VD VA/ 043VD SP/ 001VD YA/5152 YA/5122A YA/ 5122B YA/ 5121A YA/ 5121B Compressor Room Electric Motors Room

YA/5151 SP/ 013SC SP/ 011VD SP/ 012VD VA/ 031VD SP/ 001VD SP/ 014SC VA/ 032VD SP/ 001VD VA/ 033VD SP/ 001VD SP/ 021SC VA/ 034VD SP 001VD SP/ 021SC SP/ 002VD SP/ 021SC SP/ 002VD SP/ 002VD VA/ 035VD SP/ 001VD SP/ 021SC SP/ 002VD SP/021SC SP/002VD VA/ 052VD VA/ 036VD SP/ 001VD L.D. Compressor Oil Sump L.D. Compressor Oil Sump H.D. Compressor Oil Sump VAO 24 VAO 25 VAG 52 VA/ 061VR Boil Off Heater Forcing Vaporiser H.D. Compressor Oil Sump

Drip Tray Heating for Manifold Deck Sea Water Cooling ICARE Gas Sample Analyser Condensate Drains Cooler Observation Tank Drain Drain To Engine Room Atmospheric Drains Tank

2.14 Deck Steam System

(See Illustration 2.14.1a)

Deck steam is distributed to the cargo compressor room, electric motor room and main deck.

The cargo steam is used for heating of the following heat exchangers.

a) Main vaporiser

b) Forcing vaporiser

c) Gas compressor sump heating d) Vent Gas heater

e) Glycoled water heaters

The steam to inert gas plant is for the inert gas generator burner gas oil atomiser system.

Heating steam at 8 bar, 175°C is supplied from the LP heating steam range via water separators.

The heating drains from the cargo heat exchangers are

led to a condensate drains cooler (located outside the

compressor and motor room on the aft bulkhead), which is cooled from the deck sea water cooling system (see section 2.12). The drains having passed through the condensate cooler flow into an observation tank, where any oil contamination will be spotted, before returning via the atmospheric drains tank to the engine room. The observation tank on deck is fitted with a gas analyser for the indication of a possible tube failure in any of the cargo heat exchangers.

The degassing tank has its vent led on deck to a safe position above the cargo compressor room.

The heating drains from the inert gas plant are led to the contaminated drains cooler in the engine room, before passing on to the observation tank and atmospheric drains tank.

Steam to Cargo Compressor Room

The steam supply to the cargo compressor room is via isolating manual valves VA025 and VA024 located in the engine room.

Glycoled Water Heaters

The use of these 2 heaters is to ensure heating of the cofferdams and liquid dome of each tank, boil off heating and tank warm up.

The heating system maintains a permanent ambient temperature above +5°C.

The heat exchangers are of shell and tube design with the glycol water passing through the tubes in 2 passes. Steam is fed to the heaters by means of two control valves ie high flow steam controller and low flow steam controller. The high flow and low flow steam controllers operate at 5 bar and 3 bar steam pressure respectively depending on the load conditions (refer to 2.5.x for more information on glycoled heaters).

Vaporisers

Two steam heated vaporisers are located in the cargo compressor room. They are both of shell and tube type design.

One is the main vaporiser and the other is designed as the forcing vaporiser.

The steam supply to these vaporisers is by means of a pneumatic control valve on each unit.

Inert Gas Generator Atomising Steam

The atomising steam is dried in a superheater fitted in the combustion chamber envelope, before being fed to the main burner. Prior to starting the unit, water in the steam supply can be drained through the manual bypass valve on the drain trap. In service, the drains discharged from the main burner can be adjusted through a pressure reducer.

An ON-OFF pneumatic operated valve in the steam line opens a few seconds after ignition of the pilot burner and closes if the pilot and main burners are out of operation.

Operating procedures

Supplying Steam to Cargo Auxiliaries Room and Electric Motors Room

1 Open drain valves on water separators on the deck steam line.

2 Crack open manual valve VA025 and VA024 to supply steam on deck.

3 Warm through lines until steam is seen blowing out from the water separator drain lines.

4 Open fully manual valves VA025 and VA024.

5 Set up the gas heat exchangers’ drains cooler for use and opening sea water inlet and outlet cooling water valves.

6 The fuel gas heater, main heater, forcing vaporiser and main vaporiser are then set up and operated as described under operating procedures for gas heaters and vaporisers 2.5 and 2.6.

7 For the glycol cofferdam steam heater, the drains are led to the observation tank in the engine room via a manual valve which has to be opened.

8 The glycol boil off steam heater, main and forcing vaporiser, vent gas, HD and LD compressor sump heater drains are led to the condensate drains cooler and observation tank on deck, before passing to the atmospheric drains tank in the engine room.

Supplying Steam to Inert Gas Generator

1 Open isolating valves on dryer unit steam drains trap. 2 Open isolating valves on inert gas generator steam

drains trap.

3 Open heating drains return valve to drains cooler in engine room.

4 Crack open manual valve in engine room for steam supply to inert gas generator.

5 Drain water from steam lines for inert gas generator by opening the bypass on the drains trap for inert gas generator unit.

6 Open up manual valve fully when lines are fully warmed through.

Number 2 Riser Gas Heater

This unit is also supplied with steam from the deck steam system, raising the temperature of vented gas from -140 to 0°C. A high temperature alarm is provided on the gas outlet from the heater and alarm inlet temperature low (-116°). The condensate outlet has a low temperature alarm with trip, a high level alarm with trip and a level switch fitted.

2.14 Deck Steam System - Page 1 Issue: 1

Cargo Systems and Operating Manual LNG LERICI

3.1.1a IMS System Overview Issue: 1

Cargo Systems and Operating Manual

LNG LERICI

Cargo (with redundancy)

Cargo Plants Ballast & Fuel Oil Valves

Gate-Way Gate-Way

CTS

Cargo Redundant INFINET

Ballast (with redundancy)