A system for liquefying a feed gas, the system comprising:
- a coil-wound heat exchanger comprising a first bundle, a shell, and a shell space contained within the shell, the first bundle comprising:
- a warm end and a cold end;
- a mandrel centrally located within the first bundle,
- a warm bundle shell space extending from the warm end to the cold end and extending from the mandrel to the shell;
- a plurality of tubes located in the first bundle shell space, each of the plurality of tubes having a first tube end located at the warm end of the warm bundle and a second tube end located at the cold end of the warm bundle, the plurality of tubes being wound around the mandrel forming a plurality of wound layers, the plurality of wound layers being divided into a plurality of zones that are concentrically arranged in the first bundle shell space, the plurality of tubes comprising a plurality of tube sets, each of the plurality of tube sets being located in a different one of the plurality of zones;
- a feed circuit having a feed stream conduit, at least one warm end feed tube sheet located at the warm end, at least one cold end feed tube sheet located at the cold end, and a product conduit, the at least one warm end feed tube sheet and the at least one cold end feed tube sheet being in fluid flow communication with a plurality of feed tubes, the feed stream conduit, the at least one warm end feed tube sheet, the at least one cold end feed tube sheet, and the product conduit all being in fluid flow communication;
- a refrigerant circuit comprising a closed loop, the refrigerant circuit comprising:
- a compression circuit comprising at least one compression stage and at least one selected from the group of an intercooler and an aftercooler;
- a refrigerant stream conduit;
- a plurality of warm end refrigerant tube sheets in downstream fluid flow communication with the refrigerant stream conduit;
- a plurality of cold end refrigerant tube sheets located at the cold end in downstream fluid flow communication with the plurality of warm end refrigerant tube sheets;
- and
- a plurality of cold end conduits, each of the plurality of cold end conduits being in downstream fluid flow communication with a different one of the plurality of tube sets;
- a plurality of cold end valves, each of the plurality of cold end valves being located on one of the plurality of cold end conduits and outside the shell space;
- a consolidated cold end refrigerant conduit in downstream fluid flow communication with the plurality of cold end conduits and the plurality of cold end valves;
- an expansion valve in downstream fluid flow communication with the consolidated cold end refrigerant conduit;
- an expanded refrigerant conduit in downstream fluid flow communication with the expansion valve and in upstream fluid flow communication with the shell space at the cold end;
- and
- a vaporized refrigerant conduit located at the warm end, the vaporized refrigerant conduit being in downstream fluid flow communication with the shell space and in upstream fluid flow communication with the compression circuit;
- a first temperature sensor located on one of the plurality of cold end conduits and outside the shell;
- a second temperature sensor located on the consolidated cold end refrigerant conduit and outside of the shell;
- and
- a controller electrically connected to the first temperature sensor, the second temperature sensor, and the plurality of cold end valves;
- wherein the controller is adapted to adjust a position of at least one of the plurality of cold end valves based on a temperature difference between the first temperature sensor and the second temperature sensor.