Method of and system for refrigerating a fluid to be cooled down to a low temperature
AssigneeCompagnie Francaise d'Etudes et de Construction "Technip"
InventorHenri Paradowski
Life of this patent
Estimating the term…
Abstract
A process of and an apparatus for saving energy in a method of liquefying a natural gas by cooling same with the vapor from a liquid coolant sub-cooled after expansion thereof in the liquid condition, the vapor simultaneously sub-cooling the liquefied coolant, the process consisting in expanding the sub-cooled high-pressure liquid coolant in a hydraulic turbine providing mechanical power possibly for driving a rotary machine.
Claims14
A method of refrigerating at least one fluid to be cooled down to a low temperature, in particular lower than -30.degree. C., through heat exchange with at least one refrigerating fluid, each refrigerating fluid consisting of a mixture of several different components substances evolving according to a closed-loop cooling cycle while undergoing successively therein:
- at least one compression in the gaseous state, at least one pre-cooling with at least partial high pressure condensation, at least one self-refrigeration with sub-cooling of at least one liquid fraction through heat exchange in counter-current relationship with the low pressure vapor originating from at least the same sub-cooled liquid fraction of said same refrigerating fluid, at least one expansion of at least said same low pressure fraction and at least one conversion of said vapor which is recompressed thereafter, wherein the improvement consists in the step of reducing, for a same amount of treated products, the power absorbed by said compression by performing at least one aforesaid expansion dynamically so as to produce an outer mechanical work.
An apparatus for refrigerating at least one fluid to be cooled down to a low temperature, comprising:
- on the one hand an in particular open circuit for a gas to be liquefied including at least the following elements:
- at least one passage-way for the fluid to be cooled in at least one heat exchanger through which said refrigerating fluid is flowing;
- at least one member for expanding the liquid phase of said liquefied gas;
- as well as on the other hand a closed circuit for at least one refrigerating fluid, each circuit including at least the following elements:
- at least one compressor for the gaseous refrigerating fluid, at least one cooler and/or condenser;
- and at least one aforesaid heat exchanger containing at least one flow passage-way for the at least partially liquefied refrigerating fluid and at least one passage-way for the vaporized refrigerating fluid extending in a direction opposite to each aforesaid flow passage-way while being connected at its upstream end to the downstream end of said flow passage-way and having inserted therein at least one member for expanding at least one fraction of the liquid phase of said refrigerating fluid, whereas its downstream end is connected to the suction side of said compressor, wherein the improvement consists in that at least one aforesaid expansion member consists of at least one cryogenic power-absorbing turbo-machine having at least one turbine operating with a substantially incompressible, in particular hydraulic fluid.
Dependencies are inferred from the claim text.