Apparatus and process for removal of heavy hydrocarbons from a feed gas
An apparatus and process for heavy hydrocarbon (e.g., oils that include ten or more carbons, C10+ hydrocarbons, etc.) removal from a natural gas feed (e.g., a feed comprised of methane and impurities such as water and heavy hydrocarbons) can include utilization of one or more coalescing filters to provide adsorption of atomized (e.g., liquid) heavy hydrocarbons that can be present within the feed prior to the feed being fed to one or more adsorbers for adsorption of heavy hydrocarbon vapor via activated carbon beds within those adsorbers. Embodiments can be provided so that the size of downstream activated carbon bed adsorbers can be significantly reduced while also allowing such beds to have a longer life before needing to be replaced.
1 . An apparatus for removal of heavy hydrocarbon impurities from a feed comprising methane gas, the apparatus comprising:
a coalescing filter device having at least one coalescing filter that has a plurality of coalescing filter elements to remove liquid heavy hydrocarbons from within the feed, the liquid heavy hydrocarbons separated from the feed being outputtable from the coalescing filter device;
a cooling device positioned upstream of the coalescing filter device to cool the feed to a pre-selected coalescing filter device feed temperature before the feed is fed to the coalescing filter device; and
an adsorption system positioned downstream of the coalescing filter device to receive a coalescing filter device treated feed output flow output from the coalescing filter device, the adsorption system comprising a first adsorber, the first adsorber having a first bed of adsorbent material within a first vessel of the first adsorber, the first adsorber positioned to receive the coalescing filter device treated feed output flow output from the coalescing filter device so that the coalescing filter device treated feed output flow output from the coalescing filter device is passed through the first adsorber to contact the adsorbent material of the first bed of adsorbent material for removal of heavy hydrocarbons to output a treated feed gas.
2 . The apparatus of claim 1 , wherein the heavy hydrocarbons are hydrocarbons that have 10 or more carbon atoms or include at least one compressor lubricant oil.
3 . The apparatus of claim 1 , wherein the pre-selected coalescing filter device feed temperature is a temperature that is between 5° C. and −10° C.
4 . The apparatus of claim 1 , wherein the pre-selected coalescing filter device feed temperature is a temperature that is between 25° C. and −20° C., a temperature that is between 5° C. and −10° C. or a temperature that is between 0° C. and −10° C.
5 . The apparatus of claim 1 , comprising:
a heat exchanger positioned downstream of the adsorption system to cool the treated feed gas outputtable from the adsorption system to output a cooled treated feed gas,
wherein the cooling device positioned upstream of the coalescing filter device is configured to receive the cooled treated feed gas from the heat exchanger to cool the feed to the pre-selected coalescing filter device feed temperature before the feed is fed to the coalescing filter device.
6 . The apparatus of claim 1 , comprising:
a heat exchanger positioned downstream of the adsorption system to cool the treated feed gas outputtable from the adsorption system.
7 . The apparatus of claim 1 , comprising:
a heat exchanger positioned downstream of the adsorption system to cool the treated feed gas outputtable from the adsorption system to a temperature within a pre-selected liquefaction device feed temperature range or a pre-selected cryogenic processing feed temperature range for cryogenic processing at a temperature that is at or below −40° C.
8 . The apparatus of claim 1 , wherein:
the cooling device comprises a turbine or a valve.
9 . The apparatus of claim 1 , wherein:
the cooling device comprises a gas expander natural gas liquid (NGL) recovery unit or a natural gas liquefaction unit.
10 . The apparatus of claim 1 , wherein the feed has a water content of less than 2 ppmw water and is at least 70 volume percent methane.
11 . The apparatus of claim 1 , wherein the feed is providable via at least one natural gas pipeline.
12 . A process for removal of heavy hydrocarbons from a feed comprising methane, the process comprising:
cooling the feed to a pre-selected coalescing filter device feed temperature before the feed is fed to a coalescing filter device;
separating liquid heavy hydrocarbons from the feed cooled to the pre-selected coalescing filter device feed temperature via the coalescing filter device to output a coalescing filter device treated feed output flow; and
passing the coalescing filter device treated feed output flow through at least one bed of adsorbent material of at least one adsorber of an adsorption system for outputting a treated feed gas.
13 . The process of claim 12 , wherein the adsorbent material comprises activated carbon and the feed also has a water content of less than 2 ppmw water.
14 . The process of claim 12 , wherein:
the pre-selected coalescing filter device feed temperature is being a temperature that is between 25° C. and −20° C., a temperature that is between 5° C. and −10° C. or a temperature that is between 0° C. and −10° C.
15 . The process of claim 12 comprising:
cooling the treated feed gas output from the adsorption system to output a cooled treated feed gas; and
feeding the cooled treated feed gas to the cooling device to provide a cooling medium for the cooling of the feed to the pre-selected coalescing filter device feed temperature.
16 . The process of claim 12 , comprising:
cooling the treated feed gas output from the adsorption system.
17 . The process of claim 16 , wherein the cooling of the treated feed gas is provided via a chiller or a heat exchanger.
18 . The process of claim 12 , comprising:
feeding the treated feed gas output from the adsorption system to a liquefaction device for liquefaction to form a liquid natural gas (LNG) product or a cryogenic processing device for processing the treated feed gas at a temperature that is less than or equal to −40° C.
19 . The process of claim 12 , comprising:
the pre-selected coalescing filter device feed temperature being a temperature that is between 25° C. and −20° C.; and
cooling the treated feed gas output from the adsorption system to a temperature within a pre-selected liquefaction device feed temperature range or a pre-selected cryogenic processing feed temperature range for cryogenic processing at a temperature that is less than or equal to −40° C.
20 . An apparatus for removal of heavy hydrocarbon impurities from a feed comprising methane gas, the apparatus comprising:
a coalescing filter device positionable to receive the feed, the coalescing filter device having at least one coalescing filter that has a plurality of coalescing filter elements to remove liquid heavy hydrocarbons from within the feed, the liquid heavy hydrocarbons separatable from the feed being outputtable from the coalescing filter device;
a cooling device positionable upstream of the coalescing filter device to cool the feed to a pre-selected coalescing filter device feed temperature before the feed is fed to the coalescing filter device; and
the coalescing filter device connectable to an adsorption system positioned downstream of the coalescing filter device to feed a coalescing filter device treated feed output flow output from the coalescing filter device to the adsorption system so that the coalescing filter device treated feed output flow output from the coalescing filter device is passable through at least one first adsorber of the adsorption system to contact adsorbent material of a first bed of adsorbent material for removal of heavy hydrocarbons to output a treated feed gas.