Union Oil Company of California

Roland F Deering

John H Duir

John E Hines

Roland O Dhondt, Deceased

Hugh W Gowdy

Roland O Dhondt

Arnold E Kelley

Thomas A Seesee

An apparatus for removing solids from a solids upflow vessel, preferably an upflow retort, which includes a horizontally reciprocatable carriage containing a vertical feed cylinder that extends downward from a horizontal seal plate. A vertically reciprocatable piston is located inside the feed cylinder. One section of the seal plate contains a hole and a sliding door for opening and closing the hole. During normal operations when the apparatus is used to feed solids from a feed chute to an upflow vessel, the carriage is reciprocated between a first stationary position wherein the feed cylinder is aligned with the outlet of the solids feed chute while at least a portion of the closed hole in the seal plate is aligned with and below the inlet to the upflow vessel, and a second stationary position wherein the feed cylinder is aligned with the inlet to the upflow vessel while another section of the seal plate is aligned with the outlet from the feed chute. A tram-like suspension system moveably supports the carriage from elevated structural rails. When it is desired to remove solids from the upflow vessel during a maintenance shutdown, the hole in the seal plate is opened and the carriage is moved between its first and second stationary positions such that at least a portion of the open hole is aligned with and below the inlet to the upflow vessel.

System for removing solids from a solids upflow vessel

Hot, coarse, particles removed from a retort, preferably coarse particles of oil shale removed from a retort operating at superatmospheric pressure, are crushed to a size suitable for fluidization and then fed to a fluidization zone maintained under non-oxidizing conditions at substantially the pressure of the retort to forestall escape of retort gases. Raw fines are introduced into the fluidization zone and retorted without agglomeration using heat transferred from the hot retorted particles. Also introduced into the fluidization zone is a heated fluidizing gas stream comprised of recycle retort gas, which is employed to educe hydrocarbonaceous vapors from the fines and, optionally transfer heat. Educed vapors from the fluidization zone are recycled to the retort to be partially condensed and recovered as liquid and gaseous product streams along with other vapors educed in the retort.

Process for retorting oil shale with fluidized retorting of shale fines

An apparatus and process are provided for depressurizing, cooling, and, optionally, moisturizing retorted oil shale produced in an oil shale retort operated at superatmospheric pressure. Hot retorted oil shale particles are gravitated from the retort and into an elongated, multichambered vessel. In the upper chambers of the vessel the particles are partially cooled by contact with a controlled flow of liquid water. The water, having been totally vaporized, is removed from the particles at a rate which prevents the substantial flow of gases between the vessel and the retort. In the lower chambers of the vessel, the particles are first stripped of entrained hydrocarbon gas by gravitating through a countercurrently flowing stream of stripping gas and then brought to ambient pressure by gravitating through a long, narrow seal leg. Optionally, the depressurized and partially cooled particles are then further cooled and moisturized by admixing with a controlled flow of liquid water.

Apparatus for cooling, depressurizing, and moisturizing retorted oil

A dry sealing leg apparatus is comprised of four chambers through which a moving bed of retorted shale particulates from an oil shale retort is passed serially: a surge chamber, a gas injection chamber, a seal leg chamber, and a gas disengaging chamber. In the gas injection chamber, a sealing gas penetrates the moving bed of shale and divides into two portions. One portion travels countercurrently to the shale through the surge chamber and enters the retort at a positive pressure to seal product gases therein. A second portion travels co-currently with the shale through the seal leg chamber and gas disengaging chamber and exits at a pressure less than that of the retort, having been reduced in pressure by resistance to its passage through the shale. A method is provided wherein shale particulates are retorted, then passed through the dry sealing leg to reduce pressure, and crushed at a lower pressure than the operating pressure of the retort, following which the crushed retorted particulates are transported by an entraining gas stream to a fluidized combustor in which a substantial proportion of combustible materials on the shale particulates is burned to release heat energy for recovery from the flue gases.

Apparatus with moving bed pressure letdown stage for recovering retorted

Oil shale solids are pyrolyzed or retorted by contact with a non-oxidizing recycle gas in a first retorting zone to produce an effluent containing pyrolysis products and pyrolyzed oil shale solids. Liquid and gaseous product hydrocarbons are recovered from the effluent of the first retorting zone. The pyrolyzed oil shale solids are contacted with an oxygen-containing gas in a combustion zone under conditions such that at least a portion of the organic material in the pyrolyzed solids is burned to produce hot, decarbonized solids and a hot flue gas. At least a portion of the gases in the effluent from the first retorting zone is contacted in the substantial absence of molecular oxygen with a portion of the hot, decarbonized solids produced in the combustion zone in the presence of added hydrocarbon-containing fines, preferably oil shale fines, in a second retorting zone such that the gases are heated and the fines are pyrolyzed to produce pyrolyzed fines and pyrolysis products containing gases and vapors. The gases and vapors in the effluent from the second retorting zone are then recycled to the first retorting zone where they serve as the hot, non-oxidizing recycle gas.

Oil shale retorting process

Retorted shale particles are recovered from a retort and delivered to a gas lift for transport to a fluidized combustor by passage, serially, through a sealing vessel, a crusher preferably operating at retort pressure, and a surge vessel. In the sealing vessel, a sealing gas is introduced, and after commingling with the shale, the gas passes countercurrently to the shale and enters the retort, thus sealing the retort gases in the retort while separating the retorted shale from the retort gases. Retorted shale from the sealing vessel is transported to a crusher, wherein the shale is reduced in size to that suitable for combustion under fluidized conditions. To prevent the crushed shale from packing, the shale is passed to a surge vessel, wherein the crushed shale is held as a fluidized bed, from which the crushed shale is continuously withdrawn at a regulated rate and introduced into the gas lift leading to the fluidized combustor.

Apparatus for recovery of retorted shale from an oil shale retorting

Hot particles removed from a retort, preferably retort-sized particles of oil shale removed from a retort operating at superatmospheric pressure, are crushed and fed to a fluidized surge zone maintained under non-oxidizing conditions at substantially the pressure of the retort to forestall escape of retort gases. Raw fines are introduced into the surge zone and retorted without agglomeration by heat transferred from the hot retorted particles and/or a heated fluidizing gas stream to educe hydrocarbonaceous vapors. Educed vapors are scrubbed, condensed and separated into liquid and gaseous product streams, a portion of the latter being recycled to provide fluidizing process gas streams.

Process for cooling, depressurizing, and moisturizing retorted oil shale

Crushed, retorted shale particles recovered from a shale oil retort but still containing combustible materials are burned under oxidizing conditions in a fluidized combustor to remove substantially all of the hydrocarbonaceous materials. Hot combustion flue gases are recovered, divided, and delivered to two heat exchangers, the first for indirectly preheating recycled retort education gases and the second for indirectly heating water. Also recovered from the combustor are shale particles, which are introduced into a fluidized cooling vessel and therein cooled by indirectly exchanging heat with water while traces of residual hydrocarbons burn from the shale.

Process for retorting oil shale with maximum heat recovery

Retorted shale particles are recovered from a retort and delivered to a gas lift for transport to a fluidized combustor by passage, serially, through a sealing vessel, a crusher preferably operating at retort pressure, and a surge vessel. In the sealing vessel, a sealing gas is introduced, and after commingling with the shale, the gas passes counter-currently to the shale and enters the retort, thus sealing the retort gases in the retort while separating the retorted shale from the retort gases. Retorted shale from the sealing vessel is transported to a crusher, wherein the shale is reduced in size to that suitable for combustion under fluidized conditions. To prevent the crushed shale from packing, the shale is passed to a surge vessel, wherein the crushed shale is held as a fluidized bed, from which the crushed shale is continuously withdrawn at a regulated rate and introduced into the gas lift leading to the fluidized combustor.

Recovery of retorted shale from an oil shale retorting process

Oil shale retorting process with a moving bed pressure letdown stage

In gas-solids contacting processes involving the transfer of granular solids from a high-temperature, non-oxidizing treating zone through an enclosed conduit to a combustion zone, the transfer of gases between the treating zone and the combustion zone is prevented by using a novel steam sealing technique which avoids the use of mechanical sealing means and differential pressure controllers. Steam is injected into the system between the two contacting zones, and by the use of flow rate controllers and a pressure controller, a portion of such steam is forced at all times to flow through the combustion zone, while another portion thereof is withdrawn from the transfer conduit in admixture with a portion of net off-gas from the treating zone. The control system is particularly adapted for use in oil shale retorting, wherein coke on the retorted shale is burned in a combustion zone.

Use of control system for gas-solids contacting processes

A method is provided for retorting oil shale whereby full utilization of the heat energy available in the retorted shale and maximum desulfurization of the flue gas released to the atmosphere are simultaneously effected. Basically, the process comprises passing a crushed shale feed upwardly through preheating and retorting zones in a retort vessel wherein eduction of shale oil and product gases is achieved by direct heat exchange with a preheated, recycled portion of said product gases passed countercurrently to the shale feed, and then passing the retorted shale downwardly through combustion and cooling zones. Complete combustion of coke on the retorted shale in the combustion zone not only results in full utilization of the potential heat energy stored within the retorted shale but also in the production of gaseous sulfur components (mostly SO.sub.2) that chemically react with the alkaline components of the shale. Concurrent flow of gas and retorted shale in the combustion zone at temperatures between 900.degree. and 1670.degree. F permits the reaction between said SO.sub.2 and the alkaline components of the shale to proceed essentially to completion, thus desulfurizing the flue gas produced in said combustion zone.

Oil shale retorting process with desulfurization of flue gas

An improved process for educing shale oil having a low arsenic content and for producing hydrogen from oil shale in high yields comprises passing the oil shale upwardly through a gas-heated pyrolysis zone to educe oil therefrom, and then passing the spent, coke-laden shale downwardly through a gasification-combustion zone to produce hydrogen-rich heating gas and/or substantially pure hydrogen for use in catalytic refining of the educed shale oil. Air or oxygen is introduced to the gasification-combustion zone to burn part of the residual coke, thereby heating the spent shale up to gasification temperatures. Steam is injected concurrently with the oxidizing gas in order to gasify unburned coke via the water gas reaction. Improved hydrogen yields and purity and more effective shale retorting are achieved by recycling hot product gas for eduction into admixture with the gasifier product between the gasification and pyrolysis zones, and eliminating recycle to the gasification-combustion zone.

Oil shale retorting

Crushed oil shale is subjected to eduction in a solids-upflow or -downflow retort in contact with a preheated counter-currently flowing eduction gas comprising a recycled portion of the retort make gases. The problem of shale particle agglomeration is avoided by correlating the eduction gas flow rate and temperature so as to insure that the 750.degree.-850.degree. F shale temperature interval in the retort is maintained at a level sufficiently high in the retort that the total shale, or 'rock' pressure bearing down on said interval is insufficient to bring about agglomeration. It is found that the problem of agglomeration is critical to the 750.degree.-850.degree. F temperature range, and that there is a definite correlation between the oil assay of the raw shale and the permissible rock pressure which the shale particles in this temperature range can withstand without undergoing agglomeration. Provision is made for shifting the 750.degree.-850.degree. F zone upwardly or downwardly in the retort.

Growing community of inventors

Brea, CA, United States of America

Roland F Deering