Pump-free Booster

Technological Chanllenges

Two schemes are conceivable for boosting such a cryogenic liquid as LNG: pump-based and PBU (pressure boosting unit)-based boosting. In the former, the turbo-cryogenic machine, the pump, is often a source of great concern due to the following reasons:
         -Large fixed capital cost
         -Complicated operation including cooldown
         -High failure rate and subsequent maintenance
         -No maintenance onboard

In the PBU-based scheme, part of the liquid inventory is vaporized by the PBU to pressurize the whole storage tank. This scheme is difficult to apply to a large tank because
         -The design pressure of the storage tanks has to be increased.
         -It is not easy to control pressure of a large storage tank by heating.
        -All fluid in the tank needs to be heated to create sufficient pressure; this takes unduly long time for a large tank.
So, the PBU scheme is applicable only to small storage tanks.

Solution by Lattice Technology

 The Pump-free Booster of LATTICE Technology utilizes two small boosters instead of a pump. There are no moving parts. Each booster is equipped with a mini-PBU which is to pressurize the booster itself, not the main storage tank. Two boosters are operating in a proper way to guarantee continuous supply of pressurized LNG.

The advantages of the Pump-free Booster are:


-Low fixed capital cost

-Simple operation

-Low failure rate

-Easy maintenance onboard

-No need of initial pressurization of the main tank

 Pump-free Booster

 There are two process configurations: parallel and series. In the former, the two boosters operate in an alternating way; one is exporting the pressurized LNG while the other is charged with low-pressure LNG. To the contrary, in the latter configuration the first booster sends pressurized LNG in an intermittent way, and the second boost continuously exports the pressurized LNG. 

 

The pump-free boost can be used for generator engines as well as the DFDE engine. It can also replace the priming pump of the MEGI engines.

Parallel configuration                                     Series configuration

 The synergic effect magnifies if the pump-free booster is combined with the LPV LNG fuel tank for the LNG fuel gas supply system.

▲Twin cryogenic pumps with cylinder fuel tanks
▲Pump-free Booster with LPV LNG fuel tank