Heavy hydrocarbon removal from a natural gas stream

An apparatus for removing heavy hydrocarbons from a natural gas feed stream and producing a liquefied natural gas stream, wherein the heavy hydrocarbons are aliphatic hydrocarbons having six or more carbon atoms in total and/or aromatic hydrocarbons, the apparatus comprising:

• a gas-liquid separation system, comprising a stripping column or a phase separator, for receiving and separating the natural gas feed stream into a heavy hydrocarbon depleted natural gas vapor stream and a heavy hydrocarbon enriched liquid stream;
• an adsorption system, in fluid flow communication with the gas-liquid separation system, for receiving at least a portion of the heavy hydrocarbon depleted natural gas vapor stream, and comprising one or more beds of adsorbent for adsorbing heavy hydrocarbons from said at least a portion of the heavy hydrocarbon depleted natural gas vapor stream, whereby the adsorbent is selective for the heavy hydrocarbons, to thereby produce a natural gas stream lean in heavy hydrocarbons;
• an economizer heat exchanger for warming the heavy hydrocarbon depleted natural gas vapor stream, prior to said stream or portion thereof being passed through the one or more beds of the adsorption system, and cooling at least a portion of the natural gas stream lean in heavy hydrocarbons via indirect heat exchange between the heavy hydrocarbon depleted natural gas vapor stream and the at least a portion of the natural gas stream lean in heavy hydrocarbons;
• and
• a liquefier connected in fluid flow communication with the gas-liquid separation system and the second heavy hydrocarbon removal system, for receiving and cooling the natural gas feed stream prior to said stream being introduced into the gas-liquid separation system, and for receiving and liquefying at least a portion of the natural gas stream lean in heavy hydrocarbons to produce the liquefied natural gas stream, the natural gas feed stream being introduced into a warm end of the liquefier and withdrawn from an intermediate location of the liquefier, and the at least a portion of the natural gas stream lean in heavy hydrocarbons being introduced into an intermediate location of the liquefier and withdrawn from a cold end of the liquefier.