1011 results about "Fractionating column" patented technology

A low energy process for producing acetic acid by the carbonylation of methanol is disclosed. The process involves a rhodium-catalyzed system operated at less than about 14% water utilizing up to 2 distillation columns. The process is preferably controlled such that the product stream has a low level of propionic acid impurity and the level of aldehyde impurities is minimized by way of aldehyde removal or minimizing aldehyde generation. The level of iodides is controlled by contacting the product, at elevated temperatures, with ion exchange resins. In preferred embodiments, at least one silver or mercury exchanged macroreticular strong acid ion exchange resin is used to purify the product. The high temperature treatment provides the added benefit of controlling the Color Value (Pt-Co units) of the product stream.

In an integrated process and apparatus for the separation of air by cryogenic distillation and liquefaction of natural gas in which at least part of the refrigeration required to liquefy the natural gas is derived from at least one cryogenic air distillation plant comprising a main heat exchanger (7) and distillation columns (15, 17), wherein the natural gas (25) liquefies by indirect heat exchange in a heat exchanger (7, 32, 34) with a cold fluid (21, 26), the cold fluid being sent to the heat exchanger at least partially in liquid form and undergoing at least a partial vaporisation in the heat exchanger.

The present invention provides an integrated system for producing ethylene and propylene from an oxygenate to olefin (OTO) reaction system and a steam cracking system. In a preferred embodiment, at least a portion of an effluent stream from a steam cracking furnace is combined with at least a portion of an effluent stream from an OTO reaction system. Preferably the combined effluent stream is processed by one or more quench units, compression units, and / or fractionation columns. By integrating a steam cracking system with an OTO reaction system, equipment count can be reduced at a significant commercial savings. Compressor efficiency per pound of ethylene and propylene can also be advantageously increased over conventional steam cracking systems. Moreover, the amount of pollutants produced per pound of ethylene and propylene produced can be significantly reduced over the amount of pollutants produced per pound of ethylene and propylene produced in a steam cracking system.

The invention is a high capacity and high efficiency co-current vapor-liquid contacting apparatus for use in distillation columns and other vapor-liquid contacting processes. The apparatus is characterized by an arrangement of modules in horizontal stages rather than tray-like construction. The modules define a co-current contacting volume and in an exemplary configuration the modules include a liquid distributor, a demister, a receiving pan and a duct. The modules of one stage are rotated to be non-parallel with respect to the modules of an inferior stage, a superior stage, or both. Variations relate to the design of the individual elements such as the demister, liquid distributor, ducts, and contacting volumes, and the overall arrangement of the apparatus.

Contemplated plants include a refluxed absorber and a distillation column, wherein the absorber is operated at a higher pressure than the distillation column to thereby produce a cryogenic pressurized lean gas. The lean gas is further compressed to a pressure suitable for liquefaction using energy from feed gas vapor expansion. Desired separation of C2 products is ensured by temperature control of the absorber and distillation column using flow ratios of various streams within the plant, and by dividing the separation process into two portions at different pressures.

A process and apparatus for the recovery of ethane, ethylene, propane, propylene, and heavier hydrocarbons from a liquefied natural gas (LNG) stream is disclosed. The LNG feed stream is directed in heat exchanger relation with a warmer distillation stream rising from the fractionation stages of a distillation column, whereby the LNG feed stream is partially heated and the distillation stream is partially condensed. The partially condensed distillation stream is separated to provide volatile residue gas and a reflux stream, whereupon the reflux stream is supplied to the column at a top column feed position. A portion of the partially heated LNG feed stream is supplied to the column at an upper mid-column feed point, and the remaining portion is heated further to partially or totally vaporize it and thereafter supplied to the column at a lower mid-column feed position. The quantities and temperatures of the feeds to the column are effective to maintain the column overhead temperature at a temperature whereby the major portion of the desired components is recovered in the bottom liquid product from the column.

A method and apparatus for producing high purity argon by combined cryogenic distillation and adsorption technologies is disclosed. Crude argon from a distillation column or a so-called argon column is passed to a system of adsorption vessels for further purification. Depressurization gas from adsorption is introduced back, in a controlled manner, to the distillation column and / or a compressor or other means for increasing pressure. Particulate filtration and getter purification may optionally be used.

Peracetic acid in aqueous liquid solution or vapor phase is prepared on-site and on-demand in a continuous process. Peracetic acid can be produced at a controlled rate to meet the demands of a downstream operation. In one embodiment, a pipe-line reactor and distillation column is used for the production of peracetic acid. In another embodiment, an apparatus includes a continuous pot reactor and distillation column for producing peracetic acid. The present invention has the potential of providing a much safer source of aqueous peracetic acid than currently available processes, due in part to the limited inventories of reactants in the reactor, particularly those in the vapor phase.

A process for liquefying natural gas in conjunction with producing a liquid stream containing predominantly hydrocarbons heavier than methane is disclosed. In the process, the natural gas stream to be liquefied is partially cooled and divided into first and second streams. The first stream is further cooled to condense substantially all of it, expanded to an intermediate pressure, and then supplied to a distillation column at a first mid-column feed position. The second stream is also expanded to intermediate pressure and is then supplied to the column at a second lower mid-column feed position. A distillation stream is withdrawn from the column below the feed point of the second stream and is cooled to condense at least a part of it, forming a reflux stream. At least a portion of the reflux stream is directed to the distillation column as its top feed. The bottom product from this distillation column preferentially contains the majority of any hydrocarbons heavier than methane that would otherwise reduce the purity of the liquefied natural gas. The residual gas stream from the distillation column is compressed to a higher intermediate pressure, cooled under pressure to condense it, and then expanded to low pressure to form the liquefied natural gas stream.

A process for liquefying natural gas in conjunction with producing a liquid stream containing predominantly hydrocarbons heavier than methane is disclosed. In the process, the natural gas stream to be liquefied is partially cooled, expanded to an intermediate pressure, and supplied to a distillation column. The bottom product from this distillation column preferentially contains the majority of any hydrocarbons heavier than methane that would otherwise reduce the purity of the liquefied natural gas. The residual gas stream from the distillation column is compressed to a higher intermediate pressure, cooled under pressure to condense it, and then expanded to low pressure to form the liquefied natural gas stream.

Acetic acid is produced while efficiently inhibiting condensation of hydrogen iodide in a distillation column (second distillation column) for purifying crude acetic acid by further distillation.A process for producing acetic acid comprises an acetic acid collection step for feeding a first distillation column with a volatile component at least containing acetic acid, methyl acetate, methyl iodide, water, and hydrogen iodide, separating a first lower boiling point component as an overhead, and collecting a first liquid stream mainly containing acetic acid, and an acetic acid purification step for feeding a second distillation column with the first liquid stream, further separating a second lower boiling point component as an overhead, and collecting a second liquid stream containing acetic acid, wherein an alkali component is added or mixed to the first liquid stream in the manners (1) and / or (2) for distilling a liquid object to be treated containing the first liquid stream and the alkali component in the second column: (1) the alkali component is added to or mixed with the first liquid stream before the first liquid stream is fed to the second column, (2) in the second column, the alkali component is added or mixed at the same height level as or at a height level upper than a height level at which the first liquid stream is fed.

A process for producing a purified carboxylic acid having “n+1” carbon atoms comprises feeding a carboxylic acid stream containing a carboxylic acid having “n+1” carbon atoms, a hydrogen halide, a lower boiling point (bp) component, a higher bp component, and others to a first distillation column; separating a lower bp fraction containing part of the lower bp component and a higher bp fraction containing part of the higher bp component in the first column; withdrawing a side stream containing at least the carboxylic acid by side cut from the first column; feeding the side stream to a second distillation column; separating a lower bp fraction containing part of the lower bp component and a higher bp fraction containing part of the higher bp component in the second column; and withdrawing a side stream containing the carboxylic acid by side cut from the second column to recover a purified carboxylic acid; and the process further comprises feeding at least one first component (A) selected from the group consisting of an alcohol, corresponding to the carboxylic acid, having “n” carbon atom(s), and an ester of the alcohol with the carboxylic acid to the first column, and if necessary water. Such a process ensures reduction of the concentration of the hydrogen halide in the purified carboxylic acid.

The invention is a high capacity and high efficiency co-current vapor-liquid contacting apparatus for use in distillation columns and other vapor-liquid contacting processes. The apparatus is characterized by an arrangement of modules in horizontal stages rather than tray-like construction. The modules define a co-current contacting volume and in an exemplary configuration the modules include a liquid distributor, a demister, a receiving pan and a duct. The modules of one stage are rotated to be non-parallel with respect to the modules of an inferior stage, a superior stage, or both. Variations relate to the design of the individual elements such as the demister, liquid distributor, ducts, and contacting volumes, and the overall arrangement of the apparatus.

The present invention is directed to methods for improving the efficiency of processes for the recovery of natural gas liquids from a gas feed, e.g., raw natural gas or a refinery or petrochemical plant gas stream. These methods may be employed with most, if not all, conventional separation methods using distillation towers, e.g., a demethanizer and / or deethanizer column. The methods of the present invention involve installing an internal refrigeration system consisting of an open cycle refrigerant withdrawn from a distillation column and a closed cycle refrigerant derived from the open cycle refrigeration system. A separator is installed downstream of the recycle compressor discharge cooler in the open cycle refrigeration scheme. At least a portion of liquid withdrawn from this separator is used as a closed cycle refrigerant by indirect heat exchange with the inlet gas or other process streams. Thus a closed refrigeration cycle enhances the performance of the open refrigeration cycle.

A process is disclosed for recovering 1-butene from a feed steam comprising n-butane, isobutane and butene isomers using a single, divided wall distillation column. The disclosed process includes introducing the feed steam into an inlet of a first side of a distillation column, wherein the distillation column comprises a top, a bottom and a center dividing wall extending between the bottom and the top of the column and dividing the column into the first side and a second side. The process includes taking off an isobutane stream from the top of the second side of column, taking off a 1-butene stream as a bottoms stream from the second side of the column, and taking off a combination 2-butene and n-butane stream as a bottom stream from the first side of column.

The present invention relates to methods and apparatuses for the operation of a distillation tower containing a controlled freezing zone and at least one distillation section. The process and tower design are utilized for the additional recovery of hydrocarbons from an acid gas. In this process, a separation process is utilized in which a multi-component feedstream is introduced into an apparatus that operates under solids forming conditions for at least one of the feedstream components. The freezable component, although typically CO2, H2S, or another acid gas, can be any component that has the potential for forming solids in the separation system. A dividing wall is added to at least a portion of the lower distillation section of the apparatus to effect the separation of at least some fraction of the hydrocarbons in that portion of the tower.

A production process of acetic acid according to the present invention inhibits concentration of hydrogen iodide and improves a liquid-liquid separation of an overhead from a distillation column. Acetic acid is produced by distilling a mixture containing hydrogen iodide, water, acetic acid and methyl acetate in a first distillation column (3) to form an overhead and a side cut stream or bottom stream containing acetic acid, cooling and condensing the overhead in a condenser (C3) to form separated upper and lower phases in a decanter (4). According to this process, a zone having a high water concentration is formed in the distillation column above the feed position of the mixture by feeding a mixture having a water concentration of not less than an effective amount to not more than 5% by weight (e.g., 0.5 to 4.5% by weight) and a methyl acetate concentration of 0.5 to 9% by weight (e.g., 0.5 to 8% by weight) as the mixture to the distillation column and distilling the mixture. In the zone having a high water concentration, hydrogen iodide is allowed to react with methyl acetate to produce methyl iodide and acetic acid.