Abstract: A multi-reactor hydrocarbon catalytic conversion system includes at least three reactors, a feed source for providing hydrocarbon feed to the reactors and apparatus for sequentially backwardly rotating the reactors during process mode operation of the reactors. In each of a series of sequential cycles, at least one reactor currently operates in a regeneration mode position, while other reactors operate in process mode positions. A reactor having freshest catalyst is in a last process mode position, and a reactor having relatively least fresh catalyst is in a first process mode position. The reactor having relatively least fresh catalyst receives fresh feed first from the feed source, and the reactor having freshest catalyst receives the partially converted feed last. Method and apparatus are provided for rotation of the reactors, without the necessity of stopping operation of the catalytic conversion process while the shifting of the reactors is being performed.

Abstract: A control system is provided for an olefins upgrading plant wherein catalytic reactor effluent is separated to recover heavy, intermediate and light hydrocarbon streams. An improved liquid recycle system includes a level control technique for diverting a portion of a separator overhead vapor stream. Recycle flow rate may be determined by reactor temperature differential in a series of adiabatic catalytic reactors.

Abstract: Alcohols and related oxygenates are converted in a riser reactor and dense fluid catalyst bed comprising ZSM-5 type catalyst circulated through a plurality of satellite stripping-cooling zones for temperature control. Catalyst utilized comprises from 5 to 30 weight percent coke for activity and selectivity control promoting the formation of olefins and aromatics at temperatures below about 427.degree. C. (800.degree. F.).

Abstract: Apparatus and method of its utilization for controlling exothermic reactions such as the conversion of methanol to either olefin-enriched or gasoline boiling range hydrocarbons are disclosed. More particularly, the arrangement of fluid catalyst bed apparatus can be employed under varying reaction conditions in order to adjust contact between vaporous reactant and fluidized catalyst so as to maximize production as desired of either gasoline boiling range products or olefinic products useful as chemical feedstocks.

Abstract: Alcohols and related oxygenates converted in a riser reactor and dense fluid catalyst bed (ZSM-5 cat), along with the catalyst, are circulated through a plurality of satellite stripping-cooling zones for temperature control. Catalyst utilized comprises from 5 to 20 weight percent coke for activity and selectivity characteristics promoting the formation of olefins and aromatics at temperatures below 800.degree. F.

Abstract: Alcohols and related oxygenates are converted in a riser reactor and dense fluid catalyst bed (ZSM-5 zeolite catalyst) circulated through a plurality of satellite stripping-cooling zones for temperature control. Catalyst utilized comprises from 5 to 20 weight percent coke for activity and selectivity characteristics promoting the formation of olefins and aromatics at temperatures below about 427.degree. C. (800.degree. F.).

Abstract: Apparatus and method of utilization for controlling exothermic reactions such as the conversion of methanol to hydrocarbons are discussed. More particularly, the arrangement of apparatus comprising heat exchange tubes and open end baffle tubes for maintaining the hydraulic diameter within restricted limits during contact between vaporous reactant and a fluid bed of catalyst is discussed.

Abstract: Alcohols and related oxygenates converted in a riser reactor and dense fluid catalyst bed (ZSM-5 cat) circulated through a plurality of satellite stripping-cooling zones for temperature control. Catalyst utilized comprises from 5 to 20 weight percent coke for activity and selectivity characteristics promoting the formation of olefins and aromatics at temperatures below 800.degree. F.

Abstract: A process for in situ retorting of oil shale wherein an externally heated gas is circulated through a first retort zone. Surface retorting units comprised of compressors and furnaces are used to start the retorting process and to continue same until the off gas being recovered from the first retort zone reaches a temperature condition which is indicative that adequate heat is available in the retort zone to complete the retorting process without further external heating of the retorting gas. The surface retorting units are then replaced with frontal advance units comprised of low head fans which are capable of circulating the required volume of retorting gas but which require substantially less power to operate than the compressors. Also, when the units are interchanged the off gas from the first retort zone is diverted through a second retort zone to cool the off gas and to preheat the second zone.

Abstract: A method for converting lower alcohols to ethers and hydrocarbons in an exothermic restricted process control arrangement with efficient utilization of process generated heat is described.