Abstract: Systems and processes for improving quality and yield of one or more distillate products generated in a distillation column are disclosed. The system comprises a feed inlet distributor that reduces the amount of liquid entrained in vapor rising from the feed zone of the distillation column, a wash zone collection apparatus having an improved design for collecting slop wax falling from a liquid/vapor contacting structure provided in the wash zone, a recirculation subsystem for recirculating at least a portion of the collected slop wax to the top of the wash zone for distribution as wash oil, and a control subsystem. The feed inlet distributor ensures a horizontal fluid flow path free of transverse surfaces thereby minimizing atomization of liquid droplets entrained in vapor in the feed stream.

Abstract: A dual-mode dividing wall column capable of mode switching between a dividing wall column operating mode and a conventional column operating mode, and a distillation method using the dual-mode dividing wall column, wherein when compared to the existing conventional column, the invention can reduce device costs and energy and improve productivity is described. Furthermore, since a mutual conversion between a dividing wall column operating mode and a conventional column operating mode is enabled without shutting down a process, an economic loss which can occur during shutdown caused by the malfunction of a device can be prevented.

Abstract: A process for cracking hydrocarbon feedstock containing resid comprising: heating the feedstock, mixing the heated feedstock with a fluid and/or a primary dilution steam stream to form a mixture, flashing the mixture to form a vapor phase and a liquid phase which collect as bottoms and removing the liquid phase, separating and cracking the vapor phase, and cooling the product effluent, wherein the bottoms are maintained under conditions to effect at least partial visbreaking. The visbroken bottoms may be steam stripped to recover the visbroken molecules while avoiding entrainment of the bottoms liquid. An apparatus for carrying out the process is also provided.

Abstract: A process for fractionating isobutene from normal butenes, including: introducing hydrogen and a feed stream comprising isobutene, 1-butene, and 2-butene into a first column including a reaction zone containing a hydroisomerization catalyst operating at a first pressure and concurrently: (i) converting at least a portion of the 1-butene to 2-butene, and (ii) separating isobutene from the 2-butene; recovering a first overheads fraction comprising isobutene from the first column; recovering a first bottoms fraction comprising isobutene, 2-butene, and unreacted 1-butene from the first column; introducing the first bottoms fraction into a top portion of a second column comprising a fractionation column operating at a second pressure lower than the first pressure; separating the first bottoms into a second overheads fraction comprising isobutene and 1-butene and a second bottoms fraction comprising 2-butene; compressing the second overheads fraction; and introducing the compressed second overheads fraction to a lo

Abstract: A process for decoking of a process that cracks hydrocarbon feedstock containing resid and coke precursors, wherein steam is added to the feedstock to form a mixture which is thereafter separated into a vapor phase and a liquid phase by flashing in a flash/separation vessel, separating and cracking the vapor phase, and recovering cracked product. Coking of internal surfaces in and proximally downstream of the vessel is controlled by interrupting the feed flow, purging the vessel with steam, introducing an air/steam mixture to at least partially combust the coke, and resuming the feed flow when sufficient coke has been removed. An apparatus for carrying out the process is also provided.

Abstract: Hydrocarbon feedstock containing resid is cracked by a process comprising: (a) heating the hydrocarbon feedstock; (b) mixing the heated hydrocarbon feedstock with steam and optionally water to form a mixture stream; (c) introducing the mixture stream to a flash/separation apparatus to form i) a vapor phase at its dew point which partially cracks and loses/or heat causing a temperature decrease and partial condensation of the vapor phase in the absence of added heat to provide coke precursors existing as uncoalesced condensate, and ii) a liquid phase; (d) removing the vapor phase as overhead and the liquid phase as bottoms from the flash/separation apparatus; (e) treating the overhead by contacting with a hydrocarbon-containing nucleating liquid substantially free of resid and comprising components boiling at a temperature of at least about 260° C. (500° F.

Abstract: This invention is an improved distillation sequence for the separation and purification of ethylene from a cracked gas. A hydrocarbon feed enters a C2 distributor column. The top of the C2 distributor column is thermally coupled to an ethylene distributor column, and the bottoms liquid of a C2 distributor column feeds a deethanizer column. The C2 distributor column utilizes a conventional reboiler. The top of the ethylene distributor is thermally coupled with a demethanizer column, and the bottoms liquid of the ethylene distributor feeds a C2 splitter column. The ethylene distributor column utilizes a conventional reboiler. The deethanizer and C2 splitter columns are also thermally coupled and operated at a substantially lower pressure than the C2 distributor column, the ethylene distributor column, and the demethanizer column. Alternatively, a hydrocarbon feed enters a deethanizer column.

Abstract: A device comprising at least one absorber, at least one cold separator from which is extracted a gaseous phase that feeds the absorber, at least one recycling to said cold separator of at least a portion of liquid effluent that is obtained from the absorber and which is mixed with the feedstock, at least one heat exchanger for cooling the mixture prior to the recycling, at least one conduit for recovering a light hydrocarbon-enriched liquid fraction obtained from the cold separator and at least one conduit for evacuating gases from the absorber, said device being useable for the treatment of a hydrogen-rich gas or for the recovery of a hydrocarbon-enriched liquid.

Abstract: A process for treatment of a batch with four carbon atoms that contains diene compounds and a minor portion of acetylene compounds is described. A portion of the fluid that circulates in a distillation zone that is enriched with acetylene compounds is drawn off laterally, preferably in the drainage zone, and a selective hydrogenation stage is carried out in a hydrogenation zone that is outside the distillation zone. The hydrogenation effluent that is produced is recycled in the rectification zone. A C4 fraction that comprises butadiene and that is low in acetylene compounds is recovered at the top, and a C5 fraction that is enriched with oligomers is recovered at the bottom.

Abstract: Process to separate propene from gaseous fluid catalytic cracking products by performing the following steps: a) separating a feed mixture comprising the gaseous products, propene and other saturated and unsaturated hydrocarbons obtained in a fluid catalytic cracking process into a hydrocarbon-rich liquid fraction and a hydrogen containing gaseous fraction, b) separating the hydrogen containing gaseous fraction into a hydrogen-rich gaseous fraction and a hydrocarbon-rich gaseous fraction by means of a membrane separation, c) supplying the hydrocarbon-rich gaseous fraction obtained in step (b) to an absorber section and obtaining in said absorber section a lower boiling fraction rich in gaseous products having a boiling point of ethane or below and supplying the hydrocarbon-rich liquid fraction obtained in step (a) to a stripper section and obtaining in said stripper section a higher boiling fraction comprising propene and hydrocarbons having a boiling point higher than ethane.

Abstract: Pertaining mainly to the field of the petrochemical industry the method essentially includes delivery of a motive liquid into a liquid-gas ejector from a separator by a pump, feeding a liquid-gas mixture obtained in the ejector into the separator, cooling of the motive liquid with simultaneous heating of a circulating portion of a distillation residual while the motive liquid is pumped through a heat-exchanger/heater by the pump, and maintaining such an operational mode while the temperature of mediums in the separator is higher than the temperature of the motive liquid at the nozzle inlet of the ejector, where the latter is higher than the temperature of the distillation residual at the point of discharge from a rectification column and the temperature of a gas-vapor phase at the gas inlet of the ejector is lower than the temperature of the distillation residual at the point of discharge from the column.

Abstract: A fractionator has a fractionation vessel, a reactor effluent vapors inlet, a vapor feed contacting zone, a baffled contacting section above the vapor feed contacting zone, a tops section above the baffled contacting section, a heavy bottoms liquid hold-up pool section below the vapor feed contacting zone, a bottoms outlet, a bottoms recycle system with a heat exchanger. Recycled, cooled bottoms is fed back to the fractionation vessel at the heavy bottoms liquid hold-up pool section and above the vapor feed contacting zone. The improvements involve providing a separation tray and downpipe for separating cooler bottoms liquid from hotter product vapors within the fractionation vessel: to avoid condensation and absorption of product vapors by the liquid pool; to have more rapid and uniform quenching of hot liquid entering the pool; and substantially reduce costly onstream maintenance to clean fouled bottoms recycle exchangers.

Abstract: A process for fractionating a heavy hydrocarbon stream to produce a lube oil fraction having a constant, predetermined flash point. A liquid stream is removed from the fractionator, cooled in response to a fractionator top temperature and returned to the fractionator above the original draw point.

Abstract: The invention is a process for reducing capital and energy costs in ethylene recovery. Moderate pressure processing and thermally coupled fractionation steps are achieved through the use of integrator columns. Ethylene separation from cracked gas originating from ethane through gas oil feeds can now be done with thermodynamically efficient fractionation at capital cost competitive with low efficiency designs. Acetylene hydrogenation may be done before demethanization where desired, and dephlegmation is preferred to accomplish high-efficiency rectification of hydrogen and methane from ethylene. Open loop heat pumps can optionally be incorporated into the ethane/ethylene splitter fractionation step, whose desirability is controlled by optimization of capital and energy costs.

Abstract: Process for separating a feedstock stream essentially consisting of hydrogen, methane and C.sub.3 /C.sub.4 -hydrocarbons, which first passes through a pretreatment, such as, e.g., dehydrogenation, after which the feedstock stream undergoes an at least one-stage partial condensation and separation into a C.sub.3 /C.sub.4 -hydrocarbon-rich fraction and into an H.sub.2 /CH.sub.4 fraction, after which a partial stream of the H.sub.2 /CH.sub.4 fraction is mixed in the not yet pretreated feedstock stream. The H.sub.2 /CH.sub.4 gas fraction drawn off from first separator (S1) is divided into two partial streams (10, 17), and first partial stream (10) together with liquid fraction (11) of first separator (S1) is fed to a second separator (S2) after partial condensation (W2), C.sub.3 /C.sub.4 -hydrocarbon-rich liquid fraction (16), drawn off at the bottom of second separator (S2), together with the second partial stream of H.sub.2 /CH.sub.

Abstract: A process for the dehydration and/or desalination and simultaneous fractionation of a petroleum deposit effluent containing oil, associated gas and water which can be saline, which process comprises:(a) at least one step for separating the liquid and gaseous phases at the pressure P1 for removal of the gas, producing a gaseous fraction G1, on the one hand, which is removed and a liquid fraction L1, on the other hand, which is sent to step(b) at least one step for separating, at least partly, the two liquid phases mixed in the liquid fraction L1, the aqueous phase being partly removed and the oil phase containing a quantity of residual aqueous phase being sent to step (c);(c) at least one distillation step carried out at a pressure P2 which is less than, or at the most equal to, the pressure P1 in step (a), in a distillation zone C1, said distillation being carried out in the presence of the oil phase coming from step (b), said zone C1 comprising an internal heat exchange zone and a boiling zone, and enabling

Abstract: A description is given of a process for the fractionation of oil and gas on a petroleum deposit effluent, including:(a) a stage wherein the liquid and gaseous phases are separated at the gas evacuation pressure P1, producing a gaseous fraction G1, on the one hand, which is evacuated, and a liquid fraction L1, on the other hand, which is constituted at least partially of oil, sending the liquid fraction L1 to stage (b);(b) at least one distillation stage carried out at a pressure P2 which is less than or at least equal to the pressure P1 in stage (a), in a distillation zone C1 which has an internal heat exchange zone and a reboiling zone, and which permits a gaseous fraction G2 to be recovered, on the one hand, and a liquid fraction L2 to be recovered, on the other hand, which is sent to the internal exchange zone, then evacuated; and(c) at least one recompression stage at the pressure P1 of at least a part of the gaseous fraction G2 which is at least partly mixed with the gaseous fraction G2 and evacuated.

Abstract: An improved fractionating process is provided wherein a liquid stream is withdrawn from the separation zone of the fractionator, is cooled and is recycled to the fractionator at a location below the location of withdrawal of the liquid stream. An improved fractionator is provided which comprises a withdrawal point from which a liquid stream is withdrawn, a cooler to cool the withdrawn stream and a means for recycling the withdrawn stream to a point below the withdrawal point.

Abstract: A method for rectification includes steps of supplying raw materials to a rectifying column from a raw material feed pipe; returning a refluent fluid from a refluxing pipe to the column; leading a hold-up liquid from a bottom tank having a higher surface to a bottom tank having a lower surface of a liquid in a bottom portion of the column; heating the hold-up in each of bottom tanks; exchanging heat by bringing a vapor produced by heating the bottoms into counter-current contact with the reluent liquid returned to the rectifying column on plates arranged in the rectifying column, taking out a vapor from the top of the rectifying column, and taking out bottoms from the bottom tank.

Abstract: Processes are provided for the recovery of aromatic hydrocarbons from feeds comprising mixtures of aromatic and non-aromatic hydrocarbons using a mixed aromatic extraction solvent at extraction temperature of less than 250.degree. F. The mixed extraction solvent is comprised of a solvent component containing low molecular weight polyalkylene glycols and a cosolvent component containing glycol ethers. Extractive distillation and steam distillation operations are employed to separate the hydrocarbon components from the rich solvent extract. Low temperature extraction followed by subsequent heating of the rich solvent stream results in improved solvent selectivity, reduced solvent to feed ratios, improved thermal stability and energy savings.

Abstract: The aim is to separate, by cooling and partial condensation of C.sub.2+, C.sub.3+ or C.sub.4 hydrocarbons contained in a gas mixture comprising, in addition to these components, even lighter constituents. For this purpose, the gas mixture is at first cooled until condensation of a smaller part of the hydrocarbons to be separated, after which the mixture is fed into the lower region of a fractionating column. A gaseous fraction is removed from the upper region of said column and is then again cooled and partly condensed in a heat exchanger, after which this partly condensed fraction is conveyed to the top of the fractionating column in the form of a return flow. In the case of C.sub.4 separation, the C.sub.4 hydrocarbons must represent more than 50% of the hydrocarbons contained in the gas.

Abstract: Processes are provided for the recovery of aromatic hydrocarbons from feeds comprising mixtures of aromatic and non-aromatic hydrocarbons using a mixed aromatic extraction solvent at extraction temperature of less than 250.degree. F. The mixed extraction solvent is comprised of a solvent component containing low molecular weight polyalkylene glycols and a cosolvent component containing glycol ethers. Extractive distillation and steam distillation operations are employed to separate the hydrocarbon components from the rich solvent extract.

Abstract: Stabilized liquid hydrocarbon condensate is obtained by a process comprising the steps of:(a) introducing said condensate, at an elevated temperature and pressure, into a stabilizer column operated under conditions effective to separate said condensate into (i) a liquid portion which is a stabilized condensate comprising n-C.sub.4 t hydrocarbons, and (ii) a gaseous portion, which comprises CO.sub.2 and normally gaseous hydrocarbons(b) withdrawing said liquid portion, (i), from said stabilizer and dividing it into a stabilized condensate product stream that is recovered and a recycle stream that is cooled and reintroduced as liquid feed into said stabilizer column; and(c) withdrawing said gaseous portion, (ii), from said stabilizer column.

Abstract: In a fractional distillation tower which is divided into a plurality of sections by total drawoff trays, and wherein at least one fraction is withdrawn from each section. The cut point temperature between fractions is determined based on the partial pressure and temperature of the vapor in the upper portion of a section. The thus determined cut point temperature may be compared to a set point with the results of the comparison being utilized to maintain the actual cut point temperature between fractions substantially equal to the desired cut point temperature.

Abstract: An effective, economical catalytic cracking process is provided to produce quality gasoline and other hydrocarbons from whole crude oil. The catalytic cracking process is operable and particularly useful during maintenance or shutdown of associated pipestills, vacuum tower, and/or atmospheric tower.

Abstract: Method and apparatus for fractionating a hot vaporous hydrocarbon feed from a fluid catalytic cracking reactor wherein the hot vaporous feed is introduced into a fractionator zone near one end thereof and liquid is removed from a liquid collection zone and cooled in a heat extraction zone. A first portion of the cooled liquid is returned to a location between the liquid collection zone and the point of introduction of the vaporous feed and sprayed directly on hot condensed liquid flowing downwardly over an inclined baffle plate to quickly quench the liquid below the temperature at which polymerization of the constituents of the liquid can occur.

Abstract: In a fractional distillation process, the operation of a reflux pump in the process is enhanced by providing that liquid discharged from the reflux pump is returned directly to the reflux pump suction during the periods when the liquid reflux supply from the fractional distillation process is not sufficient to keep the reflux pump in constant operation.

Abstract: Water-insoluble polyoxyalkylene graft copolymers are effective anti-foam agents for reducing foaming in crude oil/gas separators. The copolymers are of formula: ##STR1## wherein R is an ethylene, propylene or butene group or a mixture thereof;R' is a hydrocarbyl group containing 1 to 8 carbon atoms;R" is a hydroxyl group, an alkoxy group or an alkyl group containing 1 to 8 carbon atoms;(a) is a number in the range 100 to 250;(b) is a number in the range 1 to 6;(c) is a number in the range 1 to 10; and(d) is a number in the range 10 to 100.They are particularly useful in breaking microgas dispersions and foams resulting from crude oils with a high gas to oil ratio.

Abstract: A hydrocarbon chargestock (11) is separated by distillation (12, 16), e.g. at least in part under reduced pressure, into a conversion feedstream (22, 24) and a vacuum residuum (17). The feedstream is converted at an elevated temperature in a conversion unit (25), e.g. a fluidized catalytic cracking system, to high temperature conversion products (26) which are passed into the bottom region of the lower portion (27) of a fractionation tower (28). The vacuum residuum (17) is passed (via 50) into the top of the lower portion (27) of the fractionation tower (28).

Abstract: A method of recovering light organic solvent from a liquid mixture containing the solvent and a process material, such as asphaltenes or coal liquefaction products. The solvent-process material mixture is treated in a solvent separation zone to separate a first vapor phase rich in solvent and a first liquid phase rich in process material. At least a portion of the liquid in the solvent separation zone is transferred to a mixing zone, where the liquid is intimately contacted with steam, under shearing conditions. The steam-liquid phase mixture thus produced is returned to the solvent separation zone and treated to separate a second vapor phase, rich in steam and solvent, and a second liquid phase, rich in process material and substantially depleted of solvent. Solvent is recovered from the first and second vapor phases.

Abstract: A method and apparatus are provided for distillation of hydrocarbon oil subject to coking threshold temperature limits. A hydrocarbon oil is heated to a first predetermined maximum temperature above which coking is likely to occur. The heated hydrocarbon oil is introduced into a first distillation zone, wherein the heated hydrocarbon oil is separated into a liquid portion and a vapor portion. The descending liquid portion is withdrawn from the bottom region of the first distillation zone, and the withdrawn liquid is reheated to a second predetermined maximum temperature, above which coking is likely to occur in the return heater line. Finally, the heated withdrawn liquid is returned to a second distillation zone, wherein a second separation occurs to achieve increased valuable products recovery. A divider arrangement maintains the first and second distillation zones physically separate from each other.

Abstract: A process is set forth for the separation of carbon dioxide from propane and higher alkanes using a carbon dioxide-loaded lean oil solvent and higher solvent flows and heat utilizations rather than mechanical energy utilization. A high pressure carbon dioxide product is produced, making the invention valuable in carbon dioxide miscible flood enhanced petroleum recovery operations.

Abstract: A process for the multi-stage condensation of an overhead fraction is disclosed. The process facilitates optimal response to changes in distillation column controls wherein column top reflux condensation is preferentially returned to said distillation column, but auxiliary surge capacity is obtained by connection to a first accumulator section of an accumulating zone, which surge capacity is supplemented by one-way flow of liquid from a cooler, second section in said accumulation zone.

Abstract: Fractionation method and apparatus are provided, wherein heavy product is withdrawn from a first fractionator and introduced into a second fractionator, which operates in a predetermined moderate pressure range. The withdrawn heavy product is separated into relatively light ends and relatively heavy ends by introducing stripping vapor into a lower section of the second fractionator. A controlled stream of light product quench, including bottoms product from the stripper, is introduced at a predetermined low temperature and a predetermined variable flow rate to the second fractionator to adjust an end point of overhead products exiting therefrom. Second fractionator overhead product is passed into the stripper, and light components from the first fractionator are introduced into the stripper, such that overhead products from the second fractionator strip light ends from the relatively light product components from the first fractionator.

Abstract: A distillation method and apparatus which comprises (a) a distillation zone adapted for the countercurrent contact of liquid and vapor, (b) a reboiler feed liquid compartment (c) means for directing distillation zone liquid into the reboiler liquid feed compartment, (d) a thermosyphon reboiler for partial vaporization of liquid thereto to produce reboiled vapor and liquid flows, (e) a conduit for the flow of liquid from the reboiler liquid feed compartment to the reboiler, (f) a reboiler return liquid compartment, (g) a conduit for the flow of reboiled liquid from the reboiler to the reboiler return compartment, (h) a conduit for the flow of reboiled vapor from the reboiler to the distillation zone, (i) means for communication of liquid by gravity flow between the reboiler feed compartment and the reboiler return compartment to provide substantially equal liquid levels in the two reservoirs, (j) a distillation zone liquid product compartment, (k) means for overflow of liquid from the reboiler return compartme

Abstract: A novel crude oil fractional distillation process, characterized by improved regulation of reflux in the de-entrainment section of a fractional distillation column, is disclosed.

Abstract: An improved process for the fractional distillation of a multi-component liquid in a multiple tray fractional distillation column having at least one sidedraw tray is disclosed, the process being characterized by elimination of draw tray overflow from at least one sidedraw tray, provision of a circulating reflux, and removal of reflux from the locus of the circulating reflux withdrawal zone.

Abstract: A control system for a fractional distillation column in which a pumparound stream is used to remove heat from the fractional distillation column is disclosed. A combination of feedforward and feedback control is utilized to control the heat removal by the pumparound stream in such a manner that smoother operation of the fractional distillation column will be accomplished and a closer approach to required product specifications will be approached.

Abstract: A process for the multistage condensation of an overhead fraction is disclosed. The process employs a single accumulation zone for at least two stages of the condensation, the accumulation zone being characterized by separate accumulation sections formed by a barrier which provides, at or near its bottom, limited liquid flow between the sections.

Abstract: A process, apparatus and control system for the fractionation of a hydrocarbon feed stream containing relatively nonvolatile impurities. A sidecut liquid stream which is substantially free of the impurities is withdrawn below the feed point. The liquid derived from the feed stream is confined to a first lateral half of the fractionation column to prevent the transfer of the nonvolatile impurities to the second lateral half from which the sidecut is removed. Liquid descending from above the feed point is collected and distributed between the two lateral halves of the column in response to temperature measurements taken in the two halves to thereby equalize liquid flow rates in the two halves. The flow of vapor between the two halves is not obstructed.

Abstract: The amount of heat input required for the sequential fractionation of a crude oil in a crude column and a vacuum column is reduced by an improved heat exchange method wherein the desalted crude oil is flashed and the flash zone liquid is split into two streams. One of the streams is first heat exchanged against an atmospheric gas oil stream from the crude column and then against a first asphalt stream from the vacuum column. The other stream is first heat exchanged against a heavy vacuum gas oil stream from the vacuum column and then against a second asphalt stream from the vacuum column. The two streams are then recombined, heated and passed into the crude column.

Abstract: In a process of extractive distillation, the combination of operating with two liquid phases in at least the uppermost trays of the column, preferably while maintaining the column operation at substantially an optimum reflux ratio, results in increased efficiencies and minimum requirements for selective solvent.