摘要:
Sweep-based gas separation processes for reducing carbon dioxide emissions from gas-fired power plants. The invention involves at least two compression steps, a combustion step, a carbon dioxide capture step, a power generate step, and a sweep-based membrane separation step. One of the compression steps is used to produce a low-pressure, low-temperature compressed stream that is sent for treatment in the carbon dioxide capture step, thereby avoiding the need to expend large amounts of energy to cool an otherwise hot compressed stream from a typical compressor that produces a high-pressure stream, usually at 20-30 bar or more.
摘要:
A process for recovering unreacted olefin in a polyolefin manufacturing process comprising the treatment of a purge bin vent gas (101). The process involves cooling and condensing the vent gas (purge stream), which contains at least an olefin, a paraffin, and a third gas, such as hydrogen or nitrogen, to produce a liquid condensate (108) and an uncondensed (residual) gas stream (114). Both streams are then passed through membrane separation steps (109; 115). The membrane separation of the uncondensed gas stream results in a residue stream (118) containing mostly a third gas and/or paraffin and a permeate stream (117) enriched in either C 2+ hydrocarbons or olefin, depending on the type of separation. The permeate from this step is recirculated within the process prior to the condensation step. The membrane separation of the condensate results in a residue stream (113) containing paraffin and a permeate stream (111) enriched in olefin, which may be recycled to the polymerization reactor.
摘要:
A process involving membrane-based gas separation and power generation, specifically for controlling carbon dioxide emissions from gas-fired power plants. The process includes a compression step, a combustion step, and an expansion/electricity generation step, as in traditional power plants. The process also includes a sweep-driven membrane separation step and a carbon dioxide removal or capture step. The carbon dioxide removal step is carried out on a portion of gas from the compression step.
摘要:
Disclosed herein is a gas separation process that utilizes ejector recycle with a membrane separation step in combination with a second separation step. The second separation step may be a second membrane separation step, or may involve a different type of separation process.
摘要:
A process for separating condensable organic components from gas streams (1). The process makes use of a membrane (2) made from a polymer material that is glassy and that has an unusually high free volume within the polymer material. Condensable organic components are removed as permeate stream (4), while a residue non-permeate stream is removed as stream (3).
摘要:
Removal of organic compounds from a water stream (3) involves gas stripping in gas stripper (1), followed by membrane separation of the stripping gas containing the organic compound (5) in membrane separator (2). Stripping can be carried out using one or multiple gas strippers and using air or any other gas as stripping gas (8). The membrane separator (2) can be a single-stage membrane unit or a multistage unit. The removal of organic compounds is particularly suited for treatment of contaminated groundwater or industrial wastewater.
摘要:
A process for separating ethane and other higher hydrocarbons from a natural or produced gas stream, having methane as its major constituent. A rubbery permselective membrane, having a propane/methane selectively of (8) or above, in a membrane unit (E) is contacted on its feed side with a gas mixture (4) typically containing methane, ethane, propane, butane, and small amounts of other hydrocarbons, water vapor, hydrogen sulfide and carbon dioxide. Carbon dioxide, water vapor, ethane and the other higher hydrocarbons permeate preferantially through the membrane and are withdrawn in permeate stream (6), and the retentate stream (5) is correspondingly enriched in methane.
摘要:
Organic vapor is recovered and concentrated from a feed stream of air having an organic vapor content of no more than 20 000 ppm by volume by pressing the stream across a thin semipermeable membrane having a selectivity for organic vapor over air of at least 50, as measured by the ratio of organic vapor permeability to nitrogen permeability, and a permeability to organic vapor of at least 3 x 10 ⁻⁷ cm ³ (STP) cm/cm ² .sec cm Hg. A partial vacuum is created on the permeate side of the membrane so that organic vapor passes preferentially through the membrane to form an organic vapor depleted air stream on the feed side and an organic vapor enriched stream on the permeate side. The organic vapor which has passed through the membrane is compressed and condensed to recover the vapor as a liquid.
摘要翻译:从有机蒸气含量不超过20000体积ppm的空气进料流中回收有机蒸气并浓缩,通过将该流压过具有至少50的空气有机蒸气选择性的薄半透膜,如所测量的 通过有机蒸汽渗透率与氮渗透率的比率和至少3×10 -6 cm 3(STP)cm / cm 2 .sec·cm Hg的有机蒸汽渗透率。 在膜的渗透侧产生部分真空,使得有机蒸汽优先通过膜,在进料侧形成有机蒸气贫化的空气流,在渗透侧形成富有机蒸气的流。 通过膜的有机蒸气被压缩并冷凝以回收作为液体的蒸气。