Flue gas decarbonization

Abstract

A process for separating carbon dioxide from a feed gas comprising carbon dioxide may comprise compressing the feed gas in a feed gas compressor to produce a compressed feed gas. The process may also comprise separating the compressed feed gas by an adsorption process comprising: using a plurality of adsorbent beds to produce a carbon dioxide-enriched product stream and a carbon dioxide-depleted stream, and a blowdown step. A blowdown gas may be removed from the adsorbent bed. The process may also comprise compressing the blowdown gas in the feed gas compressor and combining the blowdown gas with the compressed feed gas.

Claims

A process for separating carbon dioxide from a feed gas comprising carbon dioxide, the process comprising:compressing the feed gas in a feed gas compressor to produce a compressed feed gas;separating the compressed feed gas by an adsorption process comprising: using a plurality of adsorbent beds to produce a carbon dioxide-enriched product stream and a carbon dioxide-depleted stream, and a blowdown step during which a blowdown gas is removed from the adsorbent bed; andcompressing the blowdown gas in the feed gas compressor and combining the blowdown gas with the compressed feed gas.The process of claim 1, further comprising reducing the pressure of the blowdown gas prior to compression in the feed gas compressor.The process of claim 1, further comprising expanding the carbon dioxide-depleted stream to generate power.The process of claim 1, further comprising expanding a stream derived from the carbon dioxide-depleted stream to generate power.The process of claim 1, further comprising indirectly transferring heat energy from the compressed feed gas to the carbon dioxide-depleted stream.The process of claim 1, wherein the partial pressure of carbon dioxide in the compressed feed gas is maintained between 0.5 and 3.5 bara.The process of claim 1, wherein the adsorbent bed comprises a standard zeolite 13X material, a NaY zeolite material, or combinations thereof.A process for separating carbon dioxide from a feed gas comprising carbon dioxide comprising:compressing the feed gas to produce a compressed feed gas;separating the compressed feed gas by an adsorption process comprising: using a plurality of adsorbent beds comprising an adsorbent material to produce a carbon dioxide-enriched product stream and a carbon dioxide-depleted stream;wherein the partial pressure of carbon dioxide in the compressed feed gas is maintained within a given pressure range, wherein the given pressure range is a function of the adsorbent material.The process of claim 8, wherein the adsorbent bed comprises a standard zeolite 13X material, and wherein the given pressure range is between 0.5 and 3.5 bara.The process of claim 8, wherein the adsorbent bed comprises a NaY zeolite material; and wherein the given pressure range is between 0.5 and 3.5 bara.A system for separating carbon dioxide from a feed gas comprising carbon dioxide, the system comprising:a feed gas compressor configured to receive a feed gas and produce a compressed feed gas;a plurality of adsorbent beds configured to receive the compressed feed gas and to produce a carbon dioxide-enriched product stream and a carbon dioxide-depleted stream, and wherein a blowdown gas is removed therefrom; a blowdown gas conduit configured to accept the blowdown gas, wherein the feed gas compressor is in fluid flow communication with the blowdown gas conduit;a single membrane stage, a plurality of membrane stages, or combinations thereof, configured to receive the carbon dioxide-depleted stream to produce a carbon dioxide-enriched permeate stream and a carbon dioxide-lean retentate stream; anda permeate conduit configured to accept the carbon dioxide-enriched permeate stream, wherein the permeate conduit is in fluid flow communication with the feed gas compressor.The system of claim 11, wherein the blowdown gas conduit comprises a pressure reducer. The system of claim 11, further comprising an expander configured to accept the carbon dioxide-depleted stream to generate power.The system of claim 11, further comprising an expander configured to accept a stream derived from the carbon dioxide-depleted stream to generate power.The system of claim 11, further comprising a heat exchanger configured to indirectly transfer heat energy from the compressed feed gas to the carbon dioxide-depleted stream.(New) A process for separating carbon dioxide from a feed gas comprising carbon dioxide, the process comprising:compressing the feed gas in a feed gas compressor to produce a compressed feed gas;separating the compressed feed gas by an adsorption process comprising: using a plurality of adsorbent beds to produce a carbon dioxide-enriched product stream and a carbon dioxide-depleted stream, and a blowdown step during which a blowdown gas is removed from the adsorbent bed;compressing the blowdown gas in the feed gas compressor and combining the blowdown gas with the compressed feed gas;separating the carbon dioxide-depleted stream by selective permeation to produce a carbon dioxide-enriched permeate stream and a carbon dioxide-lean retentate stream; andcompressing the carbon dioxide-enriched permeate stream in the feed gas compressor.

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