259results about "Fractional condensation purification/separation" patented technology

A process for ethane extraction from a gas stream based on turboexpansion and fractionation with no mechanical refrigeration is provided. The feed gas is sweetened and dehydrated by a conventional amine process and by a molecular sieve unit, to remove carbon dioxide and water. After this pretreatment, the feed gas undergoes to a series of cooling steps through a cryogenic brazed aluminum heat exchanger and fed to a demethanizer column. A stream rich in methane is recovered from the top of this column and fed to a centrifugal compressor and subsequently routed to a booster / turboexpander. The temperature of the methane gas is greatly reduced by the expansion allowing the cooled methane stream to be a cooling source for cryogenic heat exchanger. Feed for a de-ethanizer column comes from the bottom liquids of the de-methanizer column. Ethane is recovered overhead at the de-ethanizer column.

Processes utilizing the integration of (i) processes and the associated equipment used to purify and recover propylene from propane- and / or C4+-containing refinery hydrocarbon streams, with (ii) catalytic dehydrogenation are disclosed. This integration allows for elimination of some or all of the conventional fractionation section of the dehydrogenation process, normally used to purify propylene from unconverted propane in the reactor effluent. Significant capital and utility savings are therefore attained.

A process for extracting heavier components, e.g., NGL from liquid / fluid streams such as Rich LNG (RLNG) stream(s) with the streamlined economy. The process involves heating the RLNG stream in heat exchanger(s) (LNGX) against column overhead vapour stream; not requiring separation of Feed streams into feed and reflux by splitting either pre- or post- of heat LNGX. The source liquid RLNG is processed producing liquid NGL and at same time returning purified Lean LNG (LLNG) product in its Liquid LNG form. The process operates essentially without the need for compression equipment. The process further provides without compressors vaporized natural gas at pipeline pressure and specifications. This is a system that can flexibly change product compositions and specifications of product NGL / Lean LNG / Pipeline Gas and operate in both Pipeline Specification deep 99% Ethane (C2) Extraction and Ethane (C2) Rejection NGL recovery modes with economy of equipment and energy requirements.

The present invention is process of separating cyclopentadiene and methyl cyclopentadiene from mixture containing dicyclopentadiene and dimethyl cyclopentadiene, and is especially suitable for separating and purifying cyclopentadiene and methyl cyclopentadiene from ethylene side C9 product or coarse cyclopentadiene product. The material, ethylene side C9 product or coarse cyclopentadiene product, is introduced into a high temperature cracking reactor, the high temperature cracked gas mixture is led to the first fractionating tower to separate out the fraction containing cyclopentadiene and methyl cyclopentadiene in the tower top, and the tower top fraction of the first fractionating tower is fed to the second fractionating tower to separate out cyclopentadiene in the tower top and methyl cyclopentadiene in the tower bottom.

A process for recovering a steam cracking feed from FCC absorber off-gas comprising ethylene, ethane and heavier hydrocarbons and light gases involves removing hydrogen, nitrogen, sulfur species, carbon monoxide / dioxide, methane and other impurities from the off-gas. An absorption zone is upstream of an acetylene selective hydrotreating reactor to remove sufficient hydrogen sulfide that can poison the selective hydrotreating catalyst but leave sufficient sulfur in the feed stream to prevent temperature runaway.

The invention discloses a separation process for preparing low-carbon alkene gases through conversion of methanol and aims to solve the problems that high-purity products such as hydrogen, methane, ethane and propane cannot be obtained and oxygen and carbon monoxide in dimethyl ether and gas impurities cannot be effectively eliminated in the prior art. According to the alkene gas streams through conversion of methanol, eliminating steps of oxygen and carbon monoxide are added, the alkene gas streams through conversion of methanol after elimination of oxygen and carbon monoxide sequentially passes six knockout drums and then enters a low-pressure demethanizer, a deethenizer, an acetylene hydrogenation reactor, an ethylene rectification tower, an allylene hydrogenation reactor and a propylene rectification tower for separation, the liquid from the bottoms of the first four knockout drums sequentially enter the middle-upper portion of the demethanizer, and the liquid from the bottom of the fifth knockout drum enters the upper portion of the demethanizer or returns to a section of a compressor. The separation process for preparing the low-carbon alkene gases through conversion of methanol can obtain products such as polymer grade ethylene, propylene, and the high-purity products such as hydrogen, methane, ethane and propane.

The invention relates to an oil field associated gas ethane recovery technology, or relates to an oil field associated gas ethane recovery system. The system is characterized by comprising a feed gas supercharging unit, a feed gas dehydration unit and a low-temperature fractionation unit, wherein the temperature of a bottom product of the low-temperature fractionation unit is 29.38 DEG C, and the pressure of the bottom product is 1.75 MPa; the bottom product is conveyed to a storage tank region; required cold in an ethane recovery process of the low-temperature fractionation unit is completely provided by turbo-expanders X0301 and X0302; two flows of liquid are extracted out of a tower by the low-temperature fractionation unit to perform intermediate reboiling; and compressors C0104 and C0105 are driven by the turbo-expanders X0301 and X0302 respectively. A computation model which is subjected to cryogenic separation has design reference values of adjusting parameters in real time, optimizing parameters, improving yield, reducing energy consumption and the like for established or to-be-established cryogenic device.

Disclosed is a method of efficiently separating 1,3-butadiene and methylethylketone, which are compounds of interest, from byproducts or impurities in the dehydration products of 2,3-butanediol so as to recover the compounds of interest at high purity.

Embodiments of the invention are directed to a process wherein two different unit operations (absorption and distillation) take place on either side of a top dividing wall column. One side of the dividing wall column uses absorption to separate non-condensable components from the feed; the other side of the dividing wall uses distillation to separate heavier liquid components.

A preparing method of isobutene using tert-butyl alcohol is characterized in that a fixed bed is applied as a rector for the dehydration of tert-butyl alcohol, reaction products are separated in a rectifying tower, the condenser in the tower top is a partial condenser, liquid phase is almost in infinite reflux state, only a few is collected to prevent enrichment of 8 carbon byproduct in the tower, steam phase isobutene is collected and transformed into liquid phase isobutene product after being deeply cooled in the condenser, another product water is collected from the tower bottom, and the mixture of tert-butyl alcohol and water close to azeotropic composition is collected from the lateral line to return to the fixed bed reactor. The reactor and the rectifying tower in the invention combine as a system, wherein complete reaction of tert-butyl alcohol and separation of products can be achieved through adjusting operations of rectifying tower. Water is collected from column bottom, andhigh purity isobutene is collected from tower top. The method is characterized by low investment of equipment, convenient filling of catalyst and easy operation.

Processes for providing a high purity olefin product are described. The processes involve dehydrating a feedstream comprising a mixture of alcohols having 3 to 8 carbon atoms and forming a mixed olefin stream and a water stream, the mixed olefin stream comprising a mixture of olefins having 3 to 8 carbon atoms. The mixed olefin stream is separated into at least a C3 olefin stream comprising olefins having 3 carbon atoms and a C4-8 olefin stream comprising olefins having 4 to 8 carbon atoms. The C4-8 olefin stream is separated into a C4 olefin stream comprising olefins having 4 carbon atoms and a C5-8 olefin stream comprising olefins having 5 to 8 carbon atoms. At least one of the C3 olefin stream and the C4 olefin stream is purified.

A process for removing light components from an ethylene stream may include providing a dried ethylene stream containing ethylene, ethane, CO, CO2, H2, CH4, and C3+ hydrocarbons. The process may include sending the dried ethylene stream to a stripper to produce an overhead stream containing ethylene, CO, H2 and CH4, and a bottom stream containing ethylene, ethane, CO2, and C3+ hydrocarbons. The gaseous phase on top of the stripper may be condensed in a heat exchanger cooled by a refrigerant stream to get a first gaseous phase and a first liquid phase. The first gaseous phase may be condensed in a heat exchanger cooled by liquid ethane or liquid ethylene to get a second gaseous phase containing ethylene CO, H2 and CH4 and a second liquid phase. The first and second liquid phases may be the reflux of the stripper.