Abstract:
A method is disclosed for treating gaseous effluent from a hydrocarbon pyrolysis unit to provide steam cracked tar of reduced asphaltene and toluene insolubles content. The method is suitable for preparing reduced viscosity tar useful as a fuel blending stock, or feedstock for producing carbon black, while reducing or eliminating the need for externally sourced lighter aromatics additives to meet viscosity specifications. The method comprises drawing steam cracked tar from a separation vessel, e.g., a primary fractionator or tar knock-out drum, cooling the tar, and returning it to the separation vessel to effect lower overall tar temperatures within the separation vessel, in order to reduce viscosity increasing condensation reactions. An apparatus for carrying out the method is also provided.
Abstract:
The present invention relates to a process and apparatus for recovering product from reactor effluent of a reactor for a hydrocarbon feedstream. An indigenous C4 stream is used as lean oil in a demethanizer, which facilitates significant cost and operational savings. C4 bottoms from a downstream depropanizer is used as lean oil recycle.
Abstract:
The invention relates to a process for maintaining heat balance in a fluidized bed catalytic cracking unit. More specifically, the invention relates to a combustion control method capable of maintaining or restoring heat balance by conducting, under appropriate conditions, fuel and an oxygen-containing gas to a transfer line. The transfer line conducts effluent including spent catalyst and combustion products to the unit's catalyst regeneration zone.
Abstract:
A method is disclosed for treating gaseous effluent from a hydrocarbon pyrolysis unit to provide steam cracked tar of reduced asphaltene and toluene insolubles content. The method is suitable for preparing reduced viscosity tar useful as a fuel blending stock, or feedstock for producing carbon black, while reducing or eliminating the need for externally sourced lighter aromatics additives to meet viscosity specifications. The method comprises drawing steam cracked tar from a separation vessel, e.g., a primary fractionator or tar knock-out drum, cooling the tar, and returning it to the separation vessel to effect lower overall tar temperatures within the separation vessel, in order to reduce viscosity increasing condensation reactions. An apparatus for carrying out the method is also provided.
Abstract:
A method is disclosed for treating gaseous effluent from a hydrocarbon pyrolysis unit to provide steam cracked tar of reduced asphaltene and toluene insolubles content. The method is suitable for preparing reduced viscosity tar useful as a fuel blending stock, or feedstock for producing carbon black, while reducing or eliminating the need for externally sourced lighter aromatics additives to meet viscosity specifications. The method comprises drawing steam cracked tar from a separation vessel, e.g., a primary fractionator or tar knock-out drum, cooling the tar, and returning it to the separation vessel to effect lower overall tar temperatures within the separation vessel, in order to reduce viscosity increasing condensation reactions. An apparatus for carrying out the method is also provided.
Abstract:
The present invention provides new highly-efficient separation processes and systems for separating polymerization-grade ethylene and propylene from an initial effluent stream comprising ethane, ethylene, propylene, dimethyl ether, and one or more of propane, acetylene, methyl acetylene, propadiene, methane, hydrogen, carbon monoxide, carbon dioxide and C4+ components. In one embodiment, the initial effluent stream is provided from a methanol-to-olefin reaction system. It has been discovered that an efficient separation of these components is realized when DME is partially removed in a first separation step comprising methanol and water washing steps, followed by separation of the remaining components in additional separation steps.
Abstract:
A process for producing polypropylene from olefins selectively produced from a catalytically cracked or thermally cracked naphtha stream is disclosed herein. The naphtha stream is contacted with a catalyst containing from about 10 to 50 wt. % of a crystalline zeolite having an average pore diameter less than about 0.7 nanometers at reaction conditions which include temperatures from about 500° C. to 650° C. and a hydrocarbon partial pressure from about 10 to 40 psia. The catalyst may be pre-coked with a carbonaceous feed. Alternatively, the carbonaceous feed used to coke the catalyst may be co-fed with the naphtha feed.
Abstract:
A process for producing polymers from olefins selectively produced by a two stage process for selectively producing C2 to C4 olefins from a gas oil or resid is disclosed herein. The gas oil or resid is reacted in a first stage comprising a fluid catalytic cracking unit wherein it is converted in the presence of conventional large pore zeolitic catalyst to reaction products, including a naphtha boiling range stream. The naphtha boiling range stream is introduced into a second stage comprising a process unit containing a reaction zone, a stripping zone, a catalyst regeneration zone, and a fractionation zone. The naphtha feed is contacted in the reaction zone with a catalyst containing from about 10 to 50 wt. % of a crystalline zeolite having an average pore diameter less than about 0.7 nanometers at reaction conditions which include temperatures ranging from about 500 to 650° C. and a hydrocarbon partial pressure from about 10 to 40 psia. Vapor products are collected overhead and the catalyst particles are passed through the stripping zone on the way to the catalyst regeneration zone. Volatiles are stripped with steam in the stripping zone and the catalyst particles are sent to the catalyst regeneration zone where coke is burned from the catalyst, which is then recycled to the reaction zone.
Abstract:
A process for producing polymers from olefins selectively produced from a catalytically cracked or thermally cracked naphtha stream is disclosed herein. The naphtha stream is introduced into a process unit comprised of a reaction zone, a stripping zone, a catalyst regeneration zone, and a fractionation zone. The naphtha feedstream is contacted in the reaction zone with a catalyst containing from about 10 to 50 wt. % of a crystalline zeolite having an average pore diameter less than about 0.7 nanometers at reaction conditions which include temperatures ranging from about 500° to 650° C. and a hydrocarbon partial pressure from about 10 to 40 psia. Vapor products are collected overhead and the catalyst particles are passed through the stripping zone on the way to the catalyst regeneration zone. Volatiles are stripped with steam in the stripping zone and the catalyst particles are sent to the catalyst regeneration zone where coke is burned from the catalyst, which is then recycled to the reaction zone. Overhead products from the reaction zone are passed to a fractionation zone where a stream of C3 products is recovered and a stream rich in C4 and/or C5 olefins is recycled to the stripping zone. The olefins can be further processed and polymerized to form a variety of polymer materials.
Abstract:
A process for producing polypropylene from olefins selectively produced from a catalytically cracked or thermally cracked naphtha stream is disclosed herein. The naphtha stream is contacted with a catalyst containing from about 10 to 50 wt. % of a crystalline zeolite having an average pore diameter less than about 0.7 nanometers at reaction conditions which include temperatures from about 500° C. to 650° C. and a hydrocarbon partial pressure from about 10 to 40 psia.