Abstract:
This present disclosure relates to processes and apparatuses for toluene methylation in an aromatics complex for producing paraxylene. More specifically, the present disclosure relates to processes and apparatuses wherein a toluene methylation zone is integrated within an aromatics complex for producing paraxylene thus allowing no benzene byproduct to be produced. This may be accomplished by incorporating a toluene methylation process into the aromatics complex and recycling the benzene to the transalkylation unit the aromatics complex.
Abstract:
An aromatics complex producing one or more xylene isomers offers a large number of opportunities to conserve energy by heat exchange within the complex. One previously unrecognized opportunity is through providing two parallel distillation columns operating at different pressures to separate C8 aromatics from C9+ aromatics. The parallel columns offer additional opportunities to conserve energy within the complex through heat exchange in associated xylene recovery facilities.
Abstract:
Processes and apparatuses for separating aromatic and non-aromatic hydrocarbons by extractive distillation. A solvent is mixed with the aromatic and non-aromatic hydrocarbons. A first separation column separates non-aromatic hydrocarbons from the solvent and the aromatic hydrocarbons. A second separation column separates the aromatic hydrocarbons and the solvent. A side draw stream from the second separation column is used to heat the feed stream to the first separation column. A bottom stream from the second separation may be used to heat the liquid in the first separation column. A stab-in reboiler may be used to transfer heat from the bottoms stream to the liquid in the first separation column.
Abstract:
A process is provided for separation of light olefins and paraffins and particular for the separation of propylene and propane comprising sending at least one olefin/paraffin stream to a distillation column and a membrane unit to produce an olefin stream comprising at least 92 mol % olefin. In an embodiment of the invention where the membrane unit is placed downstream from the column which can produce propylene streams at polymer grade of over 99.5 mol % propylene.
Abstract:
A process and apparatus for making olefins and aromatics are described. The process includes reforming a naphtha stream in a reforming unit to produce a reformer effluent stream comprising aromatic compounds and aliphatic compounds, wherein at least a portion of the aromatic compounds contain alkyl groups. A cracking feed stream is taken from the reformer effluent stream, heated and passed to a cracking reactor. The aliphatic compounds are selectively cracked and at least a portion of the alkyl groups on the aromatic compounds are selectively dealkylated in the presence of a cracking catalyst to produce a cracked reformer effluent stream comprising aromatic compounds and cracked olefins.
Abstract:
A process for flushing the rounded top head and rounded bottom head of a vessel used in an adsorption process in which the rounded top head and the rounded bottom head of the vessel are flushed with a flush fluid. The extract stream from the adsorption process is split into a desorbent rich stream and desorbent lean steam. The flushing fluid is a fraction separated from a desorbent lean split of the extract stream.
Abstract:
An aromatics complex producing one or more xylene isomers offers a large number of opportunities to conserve energy by heat exchange within the complex. One previously unrecognized opportunity is through providing two parallel distillation columns operating at different pressures to separate C8 aromatics from C9+ aromatics. The parallel columns offer additional opportunities to conserve energy within the complex through heat exchange in associated xylene recovery facilities.
Abstract:
A process for regenerating catalyst from an MTO process is disclosed. The process comprises providing an oxygen stream and a preheated carbon dioxide recycle stream and mixing the oxygen stream and the preheated carbon dioxide recycle stream to provide a carbon dioxide rich oxidation stream. The carbon dioxide rich oxidation stream is passed to a regenerator unit to provide a carbon dioxide rich flue gas stream. The carbon dioxide rich flue gas stream is filtered to remove the catalyst fines to produce a filtered flue gas stream. A carbon dioxide recycle stream is taken from the filtered flue gas stream.
Abstract:
A process for separating xylene from a feedstock in which the feedstock is separated into a xylene stream, a benzene rich stream and a light ends stream. Two separation zones may be utilized in which liquid from both is sent to a stabilization zone and the vapor from the stabilization zone is combined with a stream prior to the stream entering the second separation zone.