SCV Vaporization Of Low Temperature Liquid For LMG Terminals 20~200t/H

SCV Vaporization Of Low Temperature Liquid For LMG Terminals 20~200t/H

 

Submerged combustion vaporizer

 

I Advantages

As a critical vaporization equipment for LNG terminals, submerged combustion vaporizer (SCV) mainly functions as peak shaving, supplementary gas source and standby for emergency use. It is featured by:

1) high thermal efficiency up to 99% and high energy savings;

2) high vaporization capacity and 10%~100% adjustable, rapidly reacting to abrupt load changes;

3) low operating temperature of water bath (30℃only) and strong turbulence in the water bath, which result in a heat transfer coefficient outside the heat transfer tube bundle up to 5800~8000W/(m2·K) and quick start-up;

4) compact design and small footprint;

5) non-freezing at water side;

6) water sprayed to reduce NO_X emission

 

II Work principle

Fuel gas and combustion air mixed according to specified ratio are completely burned at the combustor. The hot flue gas is sprayed from the lower end of the heat transfer tube bundle through small ports on the flue gas distributor submerged in the water tank. The heat transfer tube bundle is separated from the surrounding water tank via a weir plate. In this way, the turbulence in the limited space enhances the heat transfer among flue gas, water tank and heat exchanging tube bundle. LNG at high pressure flows in from the heat transfer tube bundle and is changed into high pressure gaseous natural gas through supercritical heat transfer before it is delivered to the fuel gas network. See the work principle sketch below.

 

Fig. 1 Work principle sketch of SCV vaporizer

 

 

III Components & parameters

The SCV vaporizer package mainly consists of a submerged combustor, heat transfer tube bundle and such auxiliary systems as air blower, cooling water pump, water treatment device, alkali solution system and NO_X control system.

 

Fig. 2 SCV vaporizer

 

 

 

Type	SCV
Structure	Tube bundle type
Construction material	304SS/321SS
Manufacturing standard	ASME III
Design pressure	14MPag
Design temperature	-196℃
Design capacity	20~200t/h
Applicable liquid	LNG, liquid oxygen, liquid nitrogen, LPG
Burner type	Submerged burner (non-pre-mixed combustion)
Fuel gas	Natural gas
Fuel gas consumption	250~2500kg/h(20~200t/h)
Ignition	Three-step ignition
Flame detector	UV flame detector
Control	PID interlock control
Main measure points	LNG inlet & outlet temperature, water bath temperature
Main interlocked alarm	LNG outlet temperature, water bath temperature
Sealing	Flange
Service life of critical equipment	30 years

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IV Application

 

SCV package for PetroChina Jiangsu LNG terminal phase II (2014)

Capacity: 200t/h

Successful ignition rate: 100%

Emission: NOx＜50ppm, CO＜50ppm