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: 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.

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.

Abstract: Apparatus and processes for quenching a pyrolysis furnace effluent are provided. In one embodiment, a hydrocarbon stream comprising gas and oil vapor can be quenched with a first quench water stream to form a mixed vapor-liquid stream. The mixed vapor-liquid stream can be fed to a water quench tower to separate the vapor and liquid. The separated vapor can be further quenched with a second quench water stream in the quench tower to form an overhead vapor product comprising light hydrocarbons. Water and liquid hydrocarbons can be collected from the quench tower in an oil-water separator. The liquid hydrocarbons can be recovered from the oil-water separator. Water can be recovered from the oil-water separator. A portion of the recovered water can be cooled. The cooled water can be recycled to the first and second quench water streams.

Abstract: The invention relates to a process and apparatus for the isothermal operation of heterogeneously catalyzed reactions involving at least three phases in the form of a gaseous phase, a liquid phase and a solid phase. The invention provides apparatus for carrying out reactions involving a gaseous phase, a liquid phase and a solid phase, comprising (i) a dispersing element for dispersing a gas phase in a liquid phase to generate a reaction fluid, (ii) at least one reactor which possesses an inlet, an outlet and a reactor space bounded by heat-removing walls which are spaced apart substantially uniformly along the main flow axis of the reaction fluid, and which is fitted with catalyst-coated metal fabric, and (iii) a feed line which routes the reaction fluid from the dispersing element to the reactor inlet and is sufficiently short that the degree of dispersion of the reaction fluid does not substantially change in the course of the passage through the feed line.

Abstract: An energy efficient process scheme for a highly exothermic reaction-distillation system in which the reactor is external to the distillation column and the feed to the reactor is a mixture of at least one liquid product stream from the distillation column with or without other liquid/vapor reactants. The reactor is operated under adiabatic and boiling point conditions and at a pressure that results in vaporizing a portion of the liquid flow through the reactor due to the heat of reaction. Under these conditions, reaction temperature is controlled by reactor pressure. The pressure (and hence the temperature) is maintained at a sufficiently high level such that the reactor effluent can be efficiently used to provide reboil heat for the distillation column.

Abstract: An energy efficient process scheme for a highly exothermic reaction-distillation system in which the reactor is external to the distillation column and the feed to the reactor is a mixture of at least one liquid product stream from the distillation column with or without other liquid/vapor reactants. The reactor is operated under adiabatic and boiling point conditions and at a pressure that results in vaporizing a portion of the liquid flow through the reactor due to the heat of reaction. Under these conditions, reaction temperature is controlled by reactor pressure. The pressure (and hence the temperature) is maintained at a sufficiently high level such that the reactor effluent can be efficiently used to provide reboil heat for the distillation column.

Abstract: An apparatus and method are provided in which a vaporizer vaporizes a liquid feed for introduction to a feed conversion unit such as a steam active reformer. A condenser condenses vaporized feed from the vaporizer when introduction of feed to the feed conversion unit is stopped. Condensed, liquid feed is passed back into the vaporizer and is conserved rather than going to flare.

Abstract: An improved process for the production of styrene through dehydrogenation of ethylbenzene in the presence of steam at elevated temperatures, comprising (1) recovering heat of condensation normally lost during separation of the various components of the dehydrogenation reaction effluent, especially of ethylbenzene from styrene, without need or use of a compressor and (2) using such heat to vaporize an aqueous feed mixture of ethylbenzene and dilution water that is introduced into the dehydrogenation reactor, preferably at about atmospheric pressure, thereby obviating the need to use steam to vaporize the liquid ethylbenzene feed and also enabling much of the diluent steam needed as sensible heat for the dehydrogenation reaction to be generated from water.

Abstract: Combustion air for steam cracking furnaces is preheated by indirect heat exchange with medium pressure and low pressure steam that has been expanded through steam turbines from high pressure steam produced in the hot section of an ethylene production plant.

Abstract: Process and apparatus for a hydrocarbon conversion process, for example thermal cracking, in which feedstock is converted in a heated furnace, the furnace being heated by burning a mixture of fuel and preheated air. The preheated air is obtained by passing air through successive compression, heating and gas turbine expansion zones, the work thereby obtained from the gas turbine expansion zone being used, at least in part, to compress hydrocarbon process gas produced in the furnace.