Natural gas liquefaction precooling systems

The utility model relates to a gas treatment technical field discloses a natural gas liquefaction precooling systems, including first propylene evaporimeter, raw materials gas separator, second propylene evaporimeter, third propylene evaporimeter and fourth propylene evaporimeter, first propylene evaporimeter is connected with raw materials gas separator, raw materials gas separator takes off the tribute device through one and is connected with second propylene evaporimeter, second propylene evaporimeter, third propylene evaporimeter and fourth propylene evaporimeter connect gradually, fourth propylene evaporimeter also is connected with a heavy hydrocarbon scrubbing tower, furthermore, the pressure of first propylene evaporimeter, second propylene evaporimeter, third propylene evaporimeter and fourth propylene evaporimeter reduces in proper order. The utility model discloses a set up the propylene evaporimeter that a plurality of pressure reduce gradually, carry out precooling piecemeal to the natural gas and process, avoided cooling in the twinkling of an eye to produce the damage to equipment and pipeline, have simple structure, convenient to use's advantage.