Heavy hydrocarbon and BTEX removal from pipeline gas to LNG liquefaction

A system for removing heavy hydrocarbons from a feed gas, the system comprising:

• an absorber, wherein the absorber is configured to receive a top reflux stream and a second reflux stream within a top portion of the absorber, receive an expanded feed gas stream at a bottom portion of the absorber, and produce an absorber bottom product stream and an absorber overhead product stream, wherein the second reflux stream comprises greater than 70 mole percent methane;
• a stripper, wherein the stripper is configured to receive a feed liquid and the absorber bottom product stream and produce a stripper overhead stream and a stripper bottom product stream, wherein the stripper overhead stream is configured to pass back to the absorber as the second reflux stream;
• a pressure reduction valve configured to reduce a pressure of the absorber bottom product stream between the absorber and the stripper;
• a compressor configured to pressurize the stripper overhead stream from the stripper to form a compressed stripper overhead stream;
• and
• a heat exchanger, wherein the heat exchanger is configured to cool and at least partially condense the compressed stripper overhead stream to form the second reflux stream, and cool and at least partially condense a portion of the absorber overhead product stream to form the top reflux stream.

A system for removing heavy hydrocarbons from a feed gas, the system comprising:

• an absorber section and a stripper section, wherein the absorber section is configured to operate at a pressure higher than the stripper section,
• wherein the absorber section comprises:
• an absorber, wherein the absorber is configured to receive a top reflux stream and a second reflux stream within a top portion of the absorber, receive an expanded feed gas stream at a bottom portion of the absorber, and produce an absorber bottom product stream and an absorber overhead product stream, wherein the second reflux stream comprises greater than 70 mole percent methane, and
• wherein the stripper section comprises:
• a stripper, wherein the stripper is configured to receive a feed liquid and a reduced pressure absorber bottom product stream and produce a stripper overhead stream and a stripper bottom product stream;
• a pressure reduction valve configured to reduce a pressure of the absorber bottom product stream to produce the reduced pressure absorber bottom product stream;
• and
• a compressor configured to pressurize the stripper overhead stream from the stripper to form the second reflux stream,
• wherein a portion of the absorber overhead stream forms the top reflux stream.