Process and apparatus for converting oil shale or tar sands to oil

Information

  • Patent Grant
  • 6319395
  • Patent Number
    6,319,395
  • Date Filed
    Thursday, March 9, 2000
    24 years ago
  • Date Issued
    Tuesday, November 20, 2001
    23 years ago
Abstract
The invention relates to a continuous process for producing synthetic crude oil from oil bearing material, e.g., oil shale or tar sand, through continuous process for producing synthetic crude oil from bituminous tar sand or shale. The process includes treating the tar sand or shale to produce a fluidizable feed, feeding the fluidizable feed to a fluidized bed reactor, and fluidizing and reacting the fluidizable feed in the fluidized bed reactor with substantially only hydrogen.
Description




FIELD OF THE INVENTION




The present invention relates to a continuous process for producing synthetic crude oil (SCO) from oil shale or tar sand and an apparatus for its practice. More specifically, the present invention provides a process for treating dry tar sand or shale without prior beneficiation, in a reactor operating at elevated pressure and temperature conditions, in the presence of substantially only hydrogen gas.




BACKGROUND OF THE INVENTION




There are some tar sand systems that are successful in making synthetic crude oil (SCO), such as those in the Canadian Athabasca tar sand area that surface mine and process the tar sands, where they first separate sand (85%) from bitumen (15%) to avoid processing the sand in the reaction systems. The separated bitumen is converted to sweet, light crude oil by conventional refinery type operation. Separation of the sand from the bitumen requires beneficiating operations such as floatation cells and secondary separation equipment and processing and equipment to prepare the tar sand for flotation. In these systems, tailing oil recovery is necessary to clear the sand for disposal, however the sand is not completely cleared of bitumen.




Existing technology uses a large number of physical and chemical processing units for the treatment of wet tar sands, e.g., fluid cokers, LC finer, tumblers (being phased out by hydro-pumping), beneficiators including: primary separation vessels with floatation cells and secondary separation systems necessary to recover the bitumen from the tar sand; tailing oil recovery systems which result from the sand not being completely cleared of bitumen; tailing settling ponds which are necessary to settle and separate fine clays and other undesirable solids from the water required for floatation since the water must be reused to maximize clean-up to reduce environmental problems. These systems require large facilities along with the maintenance and reclamation required.




For example, U.S. Pat. Nos. 5,340,467 and 5,316,467 to Gregoli, et al. relate to the recovery of hydrocarbons (bitumen) from tar sands. In the Gregoli, et al. patent process, tar sand is slurried with water and a chemical additive and then the slurry is sent to a separation system. The bitumen recovery from tar sand processes described in U.S. Pat. No. 5,143,598 to Graham et al. and U.S. Pat. No. 4,474,616 to Smith, et al. also involve the formation of aqueous slurries. Other processes involving slurries, digestion, or extraction processes are taught in U.S. Pat. No. 4,098,674 to Rammler, et al., U.S. Pat. No. 4,036,732 to Irani, et al., U.S. Pat. No. 4,409,090 to Hanson, et al., U.S. Pat. No. 4,456,536 to Lorenz, et al. and Miller, et al.




In situ processing of tar sand is also known as seen from the teachings of U.S. Pat. Nos. 4,140,179, 4,301,865 and 4,457,365 to Kasevich, et al. and U.S. Pat. No. 3,680,634 to Peacock, et al.




U.S. Patent No. 4,094,767 to Gifford relates to fluidized bed retorting of tar sands. In the process disclosed by the Gifford patent, raw tar sand is treated in a fluidized bed reactor in the presence of a reducing environment, steam, recycle gases and combustion gases. The conversion of the bitumen, according to the Gifford patent, is through vaporization and cracking, thereby leaving a coked sand product. The steam and oxygen, according to Gifford are “injected into the fluidized bed in the decoking area above the spent sand cooling zone, and below the input area in the cracking zone for fresh tar sand.”




The process and apparatus of the present invention avoid the use of the large number of physical and chemical processing units used in the processing of wet tar sand by using a single continuous reactor system to hydrocrack and hydrogenate the dry tar sand. Moreover, because the present invention directly hydrogenates dry tar sand, larger quantities of valuable sweet, light crude oil are obtained. Moreover, with the present invention, less gas and substantially no coke is produced.




BRIEF SUMMARY OF THE INVENTION




The present invention relates to a continuous process for converting oil bearing material, e.g., oil shale or tar sand, and an apparatus for its practice.




Accordingly, one aspect of the present invention is to provide a continuous process and an apparatus for its practice where oil bearing material such as the kerogen in oil shale or the bitumen in tar sand is continuously treated.




Another aspect of the present invention relates to the treatment of dry tar sand.




An object of the present invention is providing a method and apparatus for converting a tar sand or shale feed to oil which can be conducted in the absence of a benificiation processes such as, for example, a hot-water extraction process to separate sand or other non reacting solids from bituminous or oil-bearing material in the feed.




An object of the present invention is providing a process for converting tar sand to oil through the use of substantially only hydrogen.




Another object of the present invention is providing a heat recovery process whereby hydrogen provides the heat necessary to bring the raw tar sand up to reactor temperature.




A still further object of the present invention is providing a process where hydrogen is used for hydrocracking and hydrogenating the bitumen in the tar sand or oil shale.




A further objective of the present invention is providing a process for using recycle and make-up hydrogen as a heat transfer vehicle.




A still further object of the present invention is providing an improved process for producing oil from tar sand or shale by reacting the tar sand or shale with substantially only hydrogen in a fluidized bed reactor, wherein the fluidizing medium is substantially hydrogen.




Yet another object of the present invention is providing a fluidized bed process where one inch or less size tar sand or shale pieces are fed into a fluidized bed reactor near the bottom of the reactor and spent sand and reaction products are removed from near the top of the reactor.




Still another object of the present invention is providing a method of recycling unreacted hydrogen that exits a reactor in which tar sand or oil shale is converted to oil. The method includes purging impurities in the exiting recycle hydrogen stream by pressure swing adsorption, maintaining the hydrogen at more than about 450 psi throughout the recycle process, admixing fresh hydrogen to the recycle hydrogen stream to form a mixture, and feeding the mixture into the reactor.




These objectives can be achieved by providing a process for producing oil from an oil bearing feed such as tar sand or oil shale. The process comprises introducing the feed in a fluidizable form into a fluidized bed reactor. A fluidizing medium enters the fluidized bed reactor where it contacts and fluidizes the fluidizable feed. The fluidizing medium includes at least hydrogen. The fluidized feed forms a fluidized bed where the feed reacts with substantially only the hydrogen at a temperature of at least 900° F. The reaction products include synthetic crude oil and spent solids which are discharged from the fluidized bed reactor.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

hows the flow diagram of one embodiment according to the present invention.





FIG. 2

shows a fluidized bed reactor for converting bitumen in tar sand to viable products in accordance with the present invention.





FIG. 3

shows a stand-alone fired heater used in the process according to the present invention.





FIG. 4

shows a compressor for supplying the hydrogen for use in the present invention.





FIG. 5

shows the flow chart of an acid gas recovery system for use in the present invention.





FIG. 6

shows the mass balance for one embodiment of the present invention.





FIG. 7

shows a flow diagram of a second embodiment according to the present invention.





FIG. 8

shows a fluidized bed reactor and lock hoppers of the second embodiment according to the present invention.




In

FIGS. 1-6

, common elements are similarly identified except for the “figure number” designation. Thus, all elements depicted in

FIG. 1

, start off with the number 1, e.g., the reactor in

FIG. 1

is identified as “104” and in

FIG. 2

the same reactor is identified as “204.”











DETAILED DESCRIPTION OF THE INVENTION




In the present invention the hydrocarbon content of the hydrocarbon bearing solids, e.g., dry tar sand or oil shale is reacted in a fluidized bed reactor with hydogen and the process is operated to avoid decompression of the hydrogen. In the present invention, the hydrocarbon bearing solid does not include bituminous or anthracite coals or similar type material. A first portion of a substantially only hydrogen stream is used to feed the oil shale or tar sand, which has been comminuted and reduced in size to form particles that are capable of being fluidized, e.g., fluidizable, into the reactor. A second portion of the hydrogen stream is used as the fluidizing medium. The hydrogen stream that is used in the present invention is formed from fresh make-up hydrogen and recycle hydrogen generated during the process, or obtained from other hydrogen producing processes. A mixed fresh-make-up and recycle hydrogen stream is discharged from a compressor at a first temperature and pressure, and a portion is diverted for admixture with the fluidizable particles of tar sand or oil shale which are injected into the fluidized bed reactor in a fan like flow, at an acute angle relative to the vertical axis of the reactor or a horizontal plane. The remainder of the hydrogen stream at said first temperature is indirectly heated to a second higher temperature by indirect heat exchange with overhead products from the fluidized bed reactor. The hydrogen stream at said second temperature is conveyed to a direct fired heater where the hydrogen stream is heated to a third temperature higher than said second temperature and then used as the fluidizing medium in the reactor to fluidize the tar sand or oil shale fluidizable particles that have been injected with the first portion of the hydrogen stream.




In the fluidized bed reactor the bitumen in the tar sand, or the kerogen in the oil shale, and hydrogen are reacted via endothermic and exothermic reactions to produce spent tar sand or oil shale and an overhead product stream that contains hydrogen, hydrogen sulfide, sulfur gases, C


1


+C


2


hydrocarbons, ammonia, fines (sand particles and clay) and vaporous products. The overhead product stream is first separated in cyclone separators within the reactor which help maintain the bed level and separate solids. The first separated overhead product is conveyed to a series of additional separators to provide a substantially particle free clean product stream. The cleaned product stream at a first temperature is conveyed to a first heat exchange unit where heat is transferred to a second portion of the hydrogen stream and results in a product stream at a second temperature lower than said first product stream temperature. The product stream at said second temperature is conveyed to a condenser to further reduce its temperature to a third temperature lower than the second product stream temperature. The product stream at said third temperature contains liquid and gas fractions and is conveyed to a separator where the gas fraction is removed, sent to an amine scrubber, and recycled as a scrubbed recycle hydrogen stream, and the liquid fraction is removed as oil product (SCO). The cooled, absorbed overhead hydrogen stream is conveyed to a heat exchanger where it contacts spent tar sand or spent shale and its temperature is elevated due to heat transferred from the spent discharge. The hydrogen stream at the elevated temperature is conveyed to a cyclone separator, or other suitable separating devices to remove particles. It then flows to the amine system to regenerate the amine solution. It is eventually conveyed to a compressor where it is combined with fresh make-up hydrogen for use in the fluidized bed reactor as the first and second hydrogen stream portions.




The invention will now be described with reference to the figures.

FIG. 1

is a flow chart of one embodiment of the present invention where tar sand is converted to oil. In accordance with the present invention, tar sand from the run of mine conveyor belt


101


is continuously fed to any suitable sizing equipment


102


for classifying tar sand, at a temperature of about 50° F. Tar sand is composed of bitumen and sand.




The bitumen in the tar sand that is processed in the present invention normally contains heavy metals which catalytically help promote the endothermic and exothermic reactions in reactor


104


. However, it may be advantageous to add additional catalyst The tar sand processed in accordance with the present invention is exemplified by the following, non-limiting example:















TAR SAND FEED






























sand







84.6




wt. %







bitumen






15.4




wt. %








carbon




83.1




wt. %








hydrogen




10.6




wt. %








sulfur




4.8




wt. %








nitrogen




0.4




wt. %








oxygen




1.1




wt. %








nickel




75




PPM








vanadium




200




PPM









100




wt. %




100




wt. %















In the present invention dry tar sand having an average particle size of that of sand is conveyed through conduit


103


as the feed for fluidized bed reactor


104


, discussed in greater detail in FIG.


2


. Tar sand particles which are oversized are either recycled to the sizing equipment


102


, or conveyed to any suitable equipment for reducing the size of the oversized feed. In the present invention, the phrase “dry tar sand” means, under atmospheric conditions, a friable, non-sticky, easily handled, substantially free flowing material.




Tar sand is fed through pressure feeder rotary valves


104


A which are circumferentially positioned adjacent and around the upper end of the fluidized bed reactor


104


, which is described in detail greater in FIG.


2


. The rotary feeders


104


A are positioned at an angle of between 20 and 60 degrees relative to the vertical reactor axis in order to “fan feed” the fluidizable sized tar sand into the top of the reactor


104


. More uniform dispersion of the tar sand in the fluidized bed reactor can be obtained when three or more rotary feed valves


104


A are positioned equidistantly around the circumference of the reactor. Although three feeders


104


A are preferred, the size of the reactor and the degree of farming desired will control the number of valve feeders. Thus, there could be 4, 5, 6, 7 or more valve feeders used present invention.




High pressure hydrogen is conveyed through lines


138


to the feeders


104


A, at a pressure of between 625 psi and 700 psi, preferably about 635 psi, to assist in injecting, feeding and dispersing the tar sand into reactor


104


.




The process performed in fluidized bed reaction


104


involves hydrocracking, which is an endothermic reaction, and hydrogenation, which is an exothermic reaction, which reactions are conducted to favor the production of liquid fuels and minimize the production of gas yields. The reactor operates at temperatures of between 800° F. and 900° F., preferably closer to 800° F. to avoid cracking the large fragments of hydrogenated bitumen in the tar sand.




It is advantageous to conduct the endothermic hydrocracking and exothermic hydrogenating processing of tar sand in reactor


104


in a predominantly hydrogen gas environment. The hydrogen atmosphere in reactor


104


is maintained at about 600 psi by fresh make-up hydrogen conveyed through line


130


from a hydrogen plant and a hydrogen recycle stream


129


which contains cleaned-up hydrogen. The volume of recycle hydrogen to fresh make-up hydrogen is preferably at least about 26 to 1.




Advantageously all the high pressure hydrogen for the process of the present invention, for reaction in reactor


104


and the various heat exchange operations, is provided by the steam powered compressor


132


. Compressor


132


receives fresh make-up hydrogen which is conveyed through line


130


and recycle hydrogen which is conveyed through lines


129


,


140


,


142


,


144


and


131


. Compressor


132


is powered by steam conveyed through line


162


from direct fired heater


135


.




Reactor


104


operates in a highly agitated fashion insuring almost instant and complete reaction between the bitumen components and hydrogen. The residence or retention time of the tar sand in reactor


104


is about 15 minutes, but could be between 10 and 20 minutes, depending on the throughput and efficiency of the reactor process. The pressure drop from the bottom to the top of the reactor


104


is about 35 psi.




Overhead products from reactor


104


are discharged from reactor


104


through cyclone separators


104


C, while solids are discharged through separator section


104


B located at the lower end of reactor


104


. The cyclones separators


104


C discharge an overhead stream, e.g., gas and vapor reaction components, off-gas and product, through their upper ends into line


110


, while separated solids are discharged through the lower ends of the dip legs. The cyclone separators


104


C extend about 20 feet down into the reactor


104


and establish the bed height in the reactor


104


.




The hot spent tar sand is continuously discharged at a pressure of about 635 psi and a temperature of about 800° F. through lock hopper valving arrangement


104


B in the lower end of reactor


104


into line


105


which conveys the discharged material to spent sand heat exchangers


106


and


108


.




The reactor overhead stream from the cyclone separators


104


C is discharged into line


110


, at a temperature of about 800° F. and a pressure of about 600 psi. The overhead stream discharged from the reactor


104


still contains dust and dry waste particles, and is first conveyed through line


110


to cyclone separator


111


where solids are separated and removed through line


150


. The gaseous effluent from separator


111


is conveyed through line


112


to an electrostatic precipitator


113


for the final cleanup. The cleaned overhead stream from precipitator


113


is removed and conveyed through line


114


, and separated solids are discharged through line


151


. Cyclone separator


111


and electrostatic precipitator


113


are of conventional design and one of ordinary skill in the art practicing the present invention can select suitable devices for performing the described operation.




The cleaned stream from the precipitator


113


, product, vaporous components, and off gas, are conveyed to in-and-out heat exchanger


115


through line


114


. In the in-and-out exchanger


115


the cleaned stream from line


114


is brought into indirect heat exchange relationship with hydrogen being conveyed through line


133


, from compressor


132


, i.e., recycle and fresh make-up hydrogen, whereby heat is transferred from the cleaned stream to the hydrogen in line


133


prior to the hydrogen stream entering the fired heater


104


. The cooled and cleaned stream, products, vaporous components, off-gases, from heat exchanger


115


is discharged into line


116


while hydrogen is discharged into line


134


which conveys the hydrogen to the direct fired heater


134


.




The cooled stream being conveyed through line


116


is introduced into condenser


117


and is discharged at a temperature of about 100° F. into line


118


. The vapor and gas stream from the condenser is conveyed through line


118


at a temperature of 100° F. and is introduced into separator


119


where vapors and liquid are separated and discharged.




Since the gas stream has been cooled down to about 100° F. and is still at a pressure of 480 psi, all carbon compounds C


3


and above have been condensed are removed from the separator


119


through flow line


155


to storage. Sour water from the separator is discharged through flow line


154


. The crude oil product stream in line


155


is a mixture of naphtha and gas oils having an A.P.I. of approximately 33.5 and is a light sweet crude. The gas stream in line


120


is conveyed to a scrubbing system, e.g., at least one amine absorption column


121


where sulfur components, e.g., hydrogen sulfide and sulfur dioxide gases, are absorbed and discharged through line


122


and conveyed to a suitable sulfur recovery plant. The amine absorption system


121


is described in greater detail in FIG.


5


.




The only gases not absorbed and removed in absorption system


121


are unreacted recycle hydrogen and C


1


+C


2


hydrocarbons which are conveyed through line


129


to heat exchangers


106


so that the spent tar sand is cooled and the recycle hydrogen and C


1


+C


2


hydrocarbons is heated and discharged into line


140


. The C


1


and C


2


hydrocarbons in line


129


will not be absorbed nor condensed but will be recycled with the unreacted hydrogen after processing in units


141


,


143


and


145


discussed hereinafter. The C


1


and C


2


hydrocarbons will reach equilibrium within the reactor


104


at about 2% and will then add to the production of crude oil per ton of tar sand. A small offset will be the increase in the recycle stream.




As discussed above, the spent sand from the reactor


104


is discharged into a succession of heat exchangers


106


and


108


. The first heat exchanger


106


cools the sand from 792° F. to 400° F. using cool recycle hydrogen being conveyed through line


129


. The cooled spent sand is conveyed in line


107


from heat exchanger


106


and introduced into a second heat exchanger


108


so that the sand is cooled by cold air introduced through line


180


from blower


181


and through line


182


, before discharging. The air heated by the spent sand is discharged into line


183


which conveys the heated air to fired heater


135


for combustion therein. Although two heat exchangers are shown, the invention contemplates using more if necessary.




The heated and partial recycle hydrogen stream conveyed through line


140


is introduced into cyclone


141


, discharged into line


142


which conveys the stream to precipitator


143


, and then through line


144


for introduction into exchanger


145


.




Fluidized Bed Reactor





FIG. 2

schematically shows the pressurized, continuously operating fluid bed reactor


204


in accordance with the present invention. Sized and screened tar sand or shale are conveyed through lines


203


and fed through pressure feeder rotary valves


204


A into the top of the reactor


204


. A portion of the gases processed in compressor


132


(FIG.


1


), and heated in fired heater


135


(

FIG. 1

) are conveyed by line


236


and introduced into fluidized bed reactor


204


in an upward direction to fluidize the bed of the reactor


204


. Another portion of the hydrogen gas from line


133


is conveyed through line


237


to tar sand feed valves


204


A through lines


238


. Another portion of the hydrogen gas feed from line


237


is diverted through lines


239


and injected into the separator section


204


B, at the bottom end of reactor


204


. Hydrogen conveyed in lines


239


is injected into the separator section


204


B of reactor


204


through injectors which are located at the ends of flow lines


239


(not shown) and aid in heat retention in the reactor system and spent sand discharge through line


205


.




High temperature and high pressure hydrogen (make-up and recycle) after passing through the direct fired heater


135


, is introduced into reactor


204


from line


236


. Reaction products and unreacted hydrogen exit the reactor through internal cyclones


204


C ensuring even flow out of the reactor. Although two cyclone separators are shown, the invention contemplates using as many as necessary to provide even flow of product gases from reactor


204


and bed height maintenance. The hot reactor effluent stream in line


210


is then conveyed to physical and chemical units, described in

FIG. 1

for cleanup heat recovery and product separation.




Direct Fired Heater




As discussed above with reference to

FIG. 1

, a portion of the fresh make-up and cleaned recycle hydrogen from the compressor is conveyed to a direct fired heater.

FIG. 3

schematically shows a fired heater


335


(


135


) that is designed to balance out the total energy required to operate the reactor system. Preheated air conveyed through feed lines


383


(


183


) is combusted with fuel in the radiant section of fired heater


335


(


135


) and elevates the temperature of the recycle and make-up hydrogen that is conveyed through line


334


(


134


). The fuel that is combusted is obtained from the C


3


fraction, e.g. propane, or natural gas produced or purchased from the described process or other sources. The hydrogen stream in lines


334


(


134


) has been preheated in the reactor in-out exchanger


115


to approximately 750° F. Since the hydrogen stream is circulated through the radiant section of the heater


335


the temperature of the hydrogen stream is elevated to a temperature of about 1200° F. Circulation of the hydrogen stream through line


133


,


134


, exchanger


115


and fired heater


335


is maintained by compressor


132


so that the 1200° F. hydrogen stream can be introduced into reactor


104


(

FIG. 1

) or


204


(FIG.


2


).




Waste heat from the radiant section of direct fired heater


335


is recovered in convection section


335


A (


135


A),


335


B (


135


B) and


335


C (


135


C). Steam separated in drum


360


(


160


) is discharged into line


361


(


161


) and introduced into convection section


335


A (


135


A) where the steam temperature is raised from about 596° F. to about 800° F. After passing through convection section


335


A (


135


A), the super heated, high pressure steam is conveyed through line


362


(


162


) to drive the steam turbine


163


. Reduced temperature and pressure steam from turbine


163


is conveyed to steam condenser


165


and the condensate recirculated via line


166


and pump


166


A The flow from pump


166


A is conveyed through line


168


(


368


) and combined with make-up water from line


167


. The water being conveyed in line


268


is introduced into convection section


335


C (


135


C), heated and discharged through line


369


(


169


) for further processing, e.g., deaeration.




Steam drum


360


(


160


) separates steam which is conveyed to radiant section


335


A (


135


A) through line


161


to produce superheated steam for the turbine compressor


163


.




The steam circulation loop include steam drum


360


(


160


), line


370


(


170


), recirculation pump


371


(


171


) and lines


372


-


373


(


172


-


173


) which conveys boiler water through radiant section


335


B (


135


B) and back into drum


360


(


160


). Water for the boiler system is provided through feed line


467


(


167


) which flows into line


468


. Line


468


is similar to flow line


168


,


368


which communication with line


169


through connection section


335




a


(


135




a


) to discharge.




As discussed above, convection section


335


A (


135


A) super heats steam which is conveyed through line


362


(


162


) to drive compressor turbine


163


, which drives compressor


132


. Steam is generated in convection section


335


B (


135


B) and make-up water and turbine condensate for boiler feed water are preheated in convection section


335


C (


135


C).




Compressor System





FIG. 4

, schematically shows a compressor


432


(


132


) driven by a high pressure steam turbine


463


(


163


) required to maintain circulation of gases to operate the reactor system


104


. Make-up hydrogen


430


(


130


) and recycle hydrogen


431


(


131


), at approximately 450 psig and 100° F. are pressurized by the compressor


432


(


132


) to approximately 670 psig and 122° F. and discharged into line


133


which conveys and introduces the high pressure hydrogen into the in-out exchanger


115


to be further heated by exchange with reactor product gases.




High pressure steam in line


162


,


362


, at 1500 psig and 800° F. drives the turbine


463


(


163


). Exhaust steam


464


(


164


) is condensed in condenser


465


(


165


), and along with make-up water


467


(


167


) is fed to the fired heater convection section


135


C,


335


C for preheating and reuse as boiler feed water make-up.




Product Separation




The product separation of

FIG. 1

, components will be described in greater detail with reference to

FIG. 5

, which schematically shows the product separation from the circulating gas stream and removal of acid gasses in an amine system. Partially cooled reactor effluent gases


516


(


116


) from the in-out exchanger


115


are further cooled in product condenser


517


(


117


) and conveyed through line


518


(


118


) to separator


519


(


119


) where condensed liquids are removed as product raw crude


555


(


155


). Overhead gases are conveyed through line


520


(


120


) to an amine absorber


5


A (


121


) where acid gasses H


2


S, CO


2


and SO


2


are absorbed by a counter current circulating amine solution. The recycle gases


5


B flow from the top of the absorber


5


A to recycle hydrogen stream


129


.




The rich amine solution


5


C exits the bottom of the absorber, flows through an amine exchanger


5


D where it is heated by exchange with hot stream amine solution


5


L and enters the top of an amine stripper


5


F. Absorbed acid gases are stripped from the amine solution by the application of heat to the solution in reboiler


545


(


145


) and are conveyed through flow line


522


(


122


) from the stripper to sulfur recovery off-site. Hot recycle gases are conveyed through line


544


(


144


) from the spent sand cooler


145


to provide heat for reboiler


545


(


145


) and the partially cooled recycled gases


5


G are further cooled by cooler


5


H and then flow through line


531


(


131


) to the suction side of compressor


132


.




Lean amine solution


5


J is circulated by amine circulation pumps


5


K through the amine exchanger


5


D and amine cooler


5


N to the top of the amine absorber


5


A to repeat the gas cleanup process.




EXAMPLE 1




The overall mass balance for the process according to the present invention is shown in

FIG. 6

, where 1000 tons/br of tar sand at 50° F. are reacted with hydrogen to produce 665 bbl/r of synthetic crude oil. The following Table provides the feed and product values for processing 1000 tons/hr. of tar sand.


















RAW MATERIALS




PRODUCTS









1000 TONS/HR. TAR SAND




665 BBL/HR SCO






1.6 MMSCF/HR HYDROGEN




5.2 MMSCF/HR STACK GAS






3.3 MMSCF/HR AIR




6600 LBS/HR SULFUR






0.5 MMSCF/HR NATURAL GAS




850 TONS/HR SPENT SAND














REACTOR DIMENSIONS AND MASS AND ENERGY BALANCES















REACTOR 104







Column Diameter




20.00 ft






Cross Section Area




34.16 ft


2








Void Fraction




0.85 (At Fluidization)






Cross Section of Sand




47.12 ft


2








Cross Section of Gas




267.04 ft


2








Reactor Volume




27394.26 ft


3








Bed Diameter




20.00 ft






Bed Height




87.20 ft






Time-Space Constant




0.25 hr






Pressure Drop




35.00 psi






TAR SAND FEED






Sand Flow Rate




1000.00 tons/hr






Density of sand




21.68 lbs./ft


3








Volumetric sand flow




16436.55 ft


3


/hr






Sand Velocity




5.81 ft/minute






Hold-up




15.00 minutes






HYDROGEN






Hydrogen Flow Rate




238661.44 lbs/hr







(45226343 SCF/hr)






Cp of H


2






3.50 btu/lb-° F. (@ 900° F.)






Hydrogen Recycle Ratio




26.52






Hydrogen Flow Rate




45.28 SCF/hr






Hydrogen Velocity




3.02 ft/s






OFF GAS






Gas Production




0.40 MMSCF/hr






MW




30.30 g/mole






Cp of flue gas




0.55 btu/lb-° F.






OFF GAS COMPOSITION






CO




0.30%






CO


2






0.20%






H


2


S




31.00%






NH


3






2.50%






C


3






66.00%






ENERGY BALANCE






OVER-ALL CONSIDERATIONS






Heat of Reaction




75.00 btu/lb. Bitumen






Cp Sand




0.19 btu/ton-° F.






Cp Bitumen




0.34 btu/lb-° F.






Cp Tarsand (sand + Bitumen)




426.70 btu/ton-° F.






Sand Feed Temperature




50.00° F.






Sand temperature




50.00° F.






at reactor inlet






Reaction temperature




800.00° F.






Sand Feed




1,000.00 tons/hr






TAR SAND REACTOR






REACTOR CONDITIONS






Heat required in reactor




356.03 MMbtu/hr






Heat generated in Reactor




22.50 MMbtu/hr






Additional Heat Required




335.24 MMbtu/hr






Minimum H


2


for reaction




9000.00 lbs./hr







(1.71 MMSCF/hr)






Additional H


2


Supplied




229736.15 lbs./hr







(43.53 MMSCF/hr)






Total H


2


Supplied




238736.15 lbs./hr







(45.24 MMSCF/hr)






C


1


-C


2


Flow within H


2


Stream




4594.72 lbs/hr






(at equilibrium-2%)




(0.08 MMSCF/hr)






Entering H


2


Temperature




1200.00° F.






Cp H


2






3.50 btu/lb-° F.






Heat Supplied by C


1


-C


2






1.01 MMbtu/hr






Heat Supplied by H


2






334.23 MMbtu/hr






H


2


Recycle ratio




26.53






REACTOR BOTTOMS COOLER:






Assures Efficient Removal of






Exiting Solids






Cold Hydrogen Cooler Stream




1,148.68 lbs./hr







(0.22 MMSCF/hr)






Heat Removed




2.73 MMbtu/hr






Entering Hydrogen Temperature




121.64° F.






Exiting Sand Temperature




791.60° F.






SAND COOLER






SAND






Sand Flow Rate




850.00 tons/hr






Temperature of Entering Sand




791.60° F.






Temperature of Spent Sand




180.00° F.






Cp Sand




0.19 btu/lb-° F.






Heat Removed




198.59 MMbtu/hr






HYDROGEN COOLANT FLOW






Hydrogen Flow




238736.15 lbs/hr







(45.24 MMSCF/hr)






Heat to Be Removed




182.96 MMb/hr






Entering Hydrogen Temperature




100.00° F.






Exiting Hydrogen Temperature




318.96° F.






AIR COOLANT






Air Required for Combustion




250000.00 lbs/hr







(3.27 MMSCF/hr)






Cp Air




0.25 btu/lb-° F.






Entering Air Temperature




50.00° F.






Exiting Air Temperature




300.00° F.






Heat Removed




15.63 MMbtu/hr






AMINE REBOILER






HYDROGEN SUPPLY






Entering Hydrogen Temperature




318.96° F.






Exiting Hydrogen Temperature




100.00° F.






AMINE BOIL-OFF






Heat Available to the system




182.96 MMbtu/hr






IN-OUT HEAT EXCHANGER






HYDROGEN TO BE HEATED






Hydrogen Flow




238736.15 lbs/hr







(45.24 MMSCF/hr)






Inlet H


2


Temperature




121.64° F.






Exiting H


2


Temperature




750.00° F.






Total Heat Required




525.05 MMbtu/hr






OFF GAS HEAT SUPPLY






Off Gas flow rate




31978.89 lbs/hr







0.40 MMSCF/hr






Condensables in vapor phase




214941.75 lbs/hr






MW




30.30 lb/lb-mole






Cp Vapor




0.55 btu/lb-° F.






Cp Liquid




0.45 btu/lb-° F.






Cp Non-Condensaes




3.00 btu/lb-° F.






Heat of Vaporization




65 .00 btu/lb






Hydrogen Recycle Flow




229736.15 hrs/hr






in Stream




(*43.53 MMSCF/hr)






Inlet Temperature




800.00° F.






Exit Temperature




350.00° F.






PRODUCT CONDENSER/COOLER




PRODUCT SIDE









Entering Temperature




350.00° F.






Exiting Temperature




100.00° F.






Condensate




24941.75 lbs/hr







(665.29 bbl/hr)






Heat Removal H


2






201.02 MMbtu/hr






Off Gas




4.40 MMbtu/hr






Condensate




38.15 MMbtu/hr






Total




243.57 MMbtu/hr






COOLER REQUIREMENT




243.57 MMbtu/hr






COMPRESSOR




HYDROGEN SIDE









Flow Rate




755412.69 SCF/min







(45.32 MMSCF/hr)






Pressure Out




670.00 psi






Pressure In




450.00 psi






DP




220.00 psi






gamma (Cp/Cv)




1.40






# Stages




3






Temperature InIet




100.00° F.






Mechanic Efficiency




0.80 *100%






Pb/Pa




1.14






Power Requirement per Stage




6366.67 hp






Total Power Required




19100.00 hp






Outlet Temperature




121.64° F.






STEAM SUPPLY






Pressure




1500.00 psi






Temperature




800.00° F.






Degree Superheat




200.00° F.






Saturation Temperature




596.20° F.






Steam Heat Vue




1364.00 btu/lb






Flow Rate




10894.28 lbs/hr






FIRED HEATER




PRODUCTS TO BE HEATED









Hydrogen Flowrate




238736.15 lbs/hr







(45.24 MMSCF/hr)






Hydrogen Temperature




750.00° F.






Water Flow Rate




10894.28 lbs/hr






Water Temperature




75.00° F.






Heat Duty




517.83 MMbtu/hr






C


3


'S (FUEL PRODUCED






BY THE PROCESS)






Flow Rate




4263.85 lbs/hr







(0.04 MMSCF/hr)






Heat of Combustion




20000.00 btu/lb






Cp




0.60 btu/lb-° F.






Temperature in




75.00° F.






Heat Supplied






(After temperature correction)




79.84 MMbtu/hr






MAKE-UP METHANE






Combustion Temperature




2200.00° F.






Heat Remaining to




437.99 MMbtu/hr






be supplied by Methane






Flow Rate




21653.89 lbs/hr







(0.51 MMSCF/hr)






Heat of Combustion




20227.00 btu/lb






(After temperature correction)






Temperature in




75.00° F.






COMBUSTION AIR






Air Required for Combustion




200000.00 lbs/hr







(2.61 MMSCF/hr)






Air Supplied 25% Excess




250000.00 lbs/hr







(3.27 MMSCF/hr)






COMPRESSOR SUCTION






COOLER (5H)






OUTFLOWS













Hydrogen









Flowrate




200000.00 lbs/hr







Temperature




100.00° F.






Required Coolant Supply





22.42 MMbtu/hr






MATERIAL BALANCE






TAR SAND REACTOR (104)






IN FLOWS






Sand







Flowrate




1000.00 tons/hr







Temperature




50.00° F.







Pressure




14.70 psia








(Force Fed)






Hydrogen







Flowrate




45.23 MMSCF/hr







Temperature




1200.00° F.







Pressure




635.00 psi






C


1-C




2


s







Flowrate




0.08 MMSCF/hr







Temperature




1200.00° F.







Pressure




635.00 psi






OUT FLOWS






Sand







Flowrate




850.00 tons/hr







Temperature




190.00° F.







Pressure




600.00 psi






Off Gas







Flowrate




43.92 MMSCF/hr







Temperature




800.00° F.







Pressure




600.00 psi







Composition




wt %







H


2






81.98







CO




0.05







CO


2






0.04







H


2


S




5.60







NH


3






0.45







C


3






11.92






Product







Flowrate




214937.52 lbs./hr







(Vapor Phase)







Temperature




800.00° F.







Pressure




600.00 psi






SAND COOLER (106, 108)





IN FLOWS









Sand







Flowrate




850.00 tons/hr







Temperature




791.92° F.







Pressure




600.00 psi






Hydrogen







Flowrate




45.23 MMSCF/hr







Temperature




100.00° F.







Pressure




500.00 psi






Air







Flowrate




3.27 MMSCF/hr







Temperature




50.00° F.







Pressure




30.00 psi






OUT FLOWS






Sand







Flowrate




850.00 tons/hr







Temperature




200.00° F.







Pressure




480.00 psi






Hydrogen







Flowrate




45.23 MMSCF/hr







Temperature




313.94° F.







Pressure




480.00 psi






Air







Flowrate




3.27 MMSCF/hr







Temperature




300.00° F.







Pressure




20.00 psi






IN-OUT HEAT EXCHANGER (115)





IN FLOWS









Hydrogen







Flowrate




45.23 MMSCF/hr







Temperature




147.60° F.







Pressure




670.00 psi






Off Gas







Flowrate




43.92 MMSCF/hr







Temperature




800.00° F.







Pressure




600.00 psi







Composition




wt %







H


2






81.98







CO




0.05







CO


2






0.04







H


2


S




5.60







NH


3






0.45







C


3






11.92






Product







Flowrate




214937.52 lbs./hr







(Vapor Phase)







Temperature




800.00° F.







Pressure




600.00 psi






OUT FLOWS






Hydrogen




Flowrate




45.23 MMSCF/hr







Temperature




750.00° F.







Pressure




650.00 psi






Off Gas




Flowrate




43.92 MMSCF/hr







Temperature




368.63° F.







Pressure




580.00 psi













Off Gas Composition as Above













Product









Flowrate




214937.52 lbs./hr







(Vapor Phase)







Temperature




368.63° F.







Pressure




580.00 psi






PRODUCT CONDENSER/





IN FLOWS






COOLER (117)









Off Gas







Flowrate




43.92 MMSCF/hr







Temperature




368.63° F.







Pressure




580.00 psi













Off Gas Composition as Above













Product









Flowrate




214937.52 lbs./hr







(Vapor Phase)







Temperature




368.63° F.







Pressure




550.00 psi






OUT FLOWS






Off Gas







Flowrate




43.92 MMSCF/hr







Temperature




100.00° F.







Pressure




540.00 psi













Off Gas Composition as Above













Product









Flowrate




214937.52 lbs./hr







(as condensate)







Temperature




100.00° F.







Pressure




540.00 psi






AMINE SYSTEM (121, FIG. 5)





IN FLOWS









Hydrogen







Flowrate




45.23 MMSCF/hr







Temperature




318.00° F.







Pressure




470.00 psi






OUT FLOWS






Hydrogen







Flowrate




45.23 MMSCF/hr







Temperature




100.00° F.







Pressure




450.00 psi














EXAMPLE 2





FIG. 7

shows another embodiment of the present invention. In this embodiment, a tar sand feed is converted into a synthetic crude oil. Run of mine tar sand from trucks is dumped into receiving, screening, and sizing equipment


702


for classifying tar sand at ambient temperature. The tar sand comprises bitumen and sand. The tar sand is crushed into relatively large fluidizable pieces that are capable of passing through a one inch mesh, or that are about one inch or less in size. In this embodiment, crushing the tar sand into fines or pieces less than sand size is preferably avoided to facilitate fines removal from the product stream. Limiting the amount of crushing can also reduce heat generation that can adversely affect tar sand processing. Limiting crushing can also help to preserve a water film that surrounds tar sand pieces. Tar sand pieces typically comprise an agglomeration of sand particles, each sand particle surrounded by a film of water and an outer layer of bitumen. On contacting a hot fluidizing flow of hydrogen during later reaction steps, the water film can rapidly evaporate assisting the tar sand pieces to disintegrate into a finely fluidized dispersion of sand particles and bitumen in hydrogen.




The crushed tar sand is conveyed through conduit


703


to feed lock hoppers


704


as the feed for fluidized bed rector


705


. The feed flow through conduit


703


and between feed lock hoppers


704


is controlled by pressure feeder rotary valves (“rotary valves”)


703


A. The bitumen in the tar sand can contain heavy metals, such as nickel, which may catalytically promote endothermic and exothermic reactions in reactor


705


. However supplemental catalyst such as, for example, nickel, cobalt, molybdenum, and vanadium can be added through catalyst feed conduit


704


A to one of the feed lock hoppers


704


to assist catalysis provided by the heavy metals in the mined tar sand or shale. The reactor


705


and related equipment are shown in more detail in FIG.


8


.




Recycle hydrogen in conduit


725


and fresh make-up hydrogen in conduit


725


A are conveyed to compressor


732


. A first mixture of recycle hydrogen and makeup hydrogen exits compressor


732


in line


733


, is cooled by heat exchanger


754


, passes through line


757


to feed lock hoppers


704


. This cooled first hydrogen mixture helps to prevent the tar sand from gumming by keeping the tar sand cool and forces the crushed tar sand into the reactor


705


which operates at a pressure of about 600 psi. Preferably, the first hydrogen mixture reaches the lock hoppers


704


at a temperature of about 100° F. or less, and maintains the tar sand at a temperature of about 100° F. or less. The tar sand is fed from feed lock hoppers


704


through conduit


704


B and into reactor


705


through a feed inlet


705


H, assisted by the first hydrogen mixture at 670 psi pressure in line


757


. There are three feed lock hoppers in this embodiment, but the number may vary in other embodiments. The tar sand can be fed into the rector approximately horizontally, near the bottom of the reactor, and just above ceramic grid


705


C. Equipment for treating mined tar sand or shale feed material and for feeding the material into reactor, such as the equipment described above, can be referred to as a feed introducing system. Equipment for feeding tar sand or shale feed material into the reactor, such as the feed lock hoppers


704


, conduit


703


and rotary valves


703


A, can be referred to as a feeder device.




On entering the reactor


705


, the tar sand is contacted and heated by a second hydrogen mixture. The second hydrogen mixture flows from fired heater


735


and into a gas inlet


705


I at the bottom of the reactor


705


B through ceramic lined conduit line


736


at a temperature of about 1500° F. and about 635 psi pressure. The second hydrogen mixture passes through a slotted fire brick or ceramic grid


705


C before contacting the entering tar sand. The flow rate and velocity of the second hydrogen mixture are sufficient to fluidize the tar sand and to beat the tar sand to a desired reaction temperature. The heated tar sand and the second hydrogen mixture react in the reactor


705


in a fluidized bed


705


E at the desired reaction temperature of about 900° F. to about 1000° F., and at a pressure of about 600 psi. The second hydrogen mixture flow rate typically exceeds the minimum needed for complete tar sand reaction wit hydrogen by a factor of about 15 to about 26, and preferably by a factor of about 21. Adjustment of the second hydrogen mixture flow rate may require adjustment of other reaction parameters to maintain the fluidized bed


705


E at desired pressures and temperatures. The tar sand reacts with the hydrogen mixture in the fluidized bed


705


E by endothermic hydrocracking and exothermic hydrogenating reactions. Reaction products include substantially sulfur-free hydrocarbon that are condensable into hydrocarbon liquids at standard temperature and pressure.




Reaction products including synthetic crude oil and unreacted hydrogen mixture exit the reactor


705


through a product stream outlet


705


F as an overhead or product stream through cyclone separators


705


A and into exit conduit line


710


. Solids entrained in the overhead product stream, such as sand particles and fines, are trapped by the cyclone separators


705


A and are deposited near the ceramic screen


705


C at the bottom of the reactor


705


B, where they are again entrained in the fluidized bed


705


E. Eventually, the spent sand and solids exit the reactor


705


through a conduit line


705


D. The overhead stream flows through a hydrogen recycling system wherein hydrogen is removed from the remainder of the overhead stream, treated, and returned to the reactor.




It is advantageous to conduct the endothermic hydrocracking and exothermic hydrogenation reactions in a predominantly hydrogen gas environment. The first and second hydrogen mixtures are mixtures of fresh make-up hydrogen and recycle hydrogen which are fed to a compressor


732


via conduit lines


725


A and


725


respectively. The recycle hydrogen contains hydrogen and up to 5 mole percent of combined methane and ethane. The amount of combined methane and ethane in the recycle hydrogen is maintained by a purge in a hydrogen recycle system connected to the reactor


705


. The volume of recycle hydrogen to fresh make-up hydrogen is preferably about 21:1, but can vary from about 15:1 to about 26:1.




The reactor


705


is operated so as to highly agitate the reactants and ensure rapid and complete reaction between the bitumen components and hydrogen in the reactor


705


. The residence or reaction time of the tar sand in reactor


705


is about 10 minutes, but can be between 5 and 20 minutes, depending on the throughput and efficiency of the reactor process. The pressure drop from the bottom to the top of the fluidized bed


705


E is about 35 psi.




Spent sand, at a temperature of about 950° F., overflows from reactor


705


into conduit line


705


D through a spent solids outlet


705


G. The height of the conduit line


705


D may establish the maximum height of the fluidized bed


705


E. The sand then flows through spent sand lock hoppers


706


, through conduit line


707


and into rotary coolers


708


which cool the sand from a temperature of 950° F. to about 665° F. The cooled sand can be discharged and used, for example, for land reclamation.




The rotary coolers


708


can use ambient air fed through air intake


778


to cool the spent sand. The air exits the rotary coolers


708


through line


779


at a temperature of about 625° F. and passes through a cyclone


780


to remove entrained fines. The fines are discharged through conduit line


785


. The cooling air is preheated by the spent sand, then passes to the fired heater


735


via blower


782


and conduit lines


781


and


783


where the air is used as preheated combustion air.




The number of feed lock hoppers


704


and spent sand lock hoppers


706


is controlled by the size of the reactor, thus more or less than the three feed lock hoppers


704


and more or less than three spent sand lock hoppers can be used in the present invention.




The reactor overhead stream from the cyclone separator


705


A is discharged into line


710


, and then to hot gas clean-up


711


. The overhead stream in line


710


exits the reactor


705


at about 950° F. and enters the hot gas clean-up


711


. Ceramic bag collectors or filters in the hot gas clean-up


711


remove and collect fines remaining in the overhead stream. The filters are periodically pulsated by a back flow of a 650 psi, 875° F. hydrogen mixture taken from in-out heat exchanger


715


via conduit line


734


A. Collected fine and solids are removed from the bottom of the hot gas clean-up


711


and are collected in hot gas clean-up lock hoppers


712


. The fines can be combined with spent sand and used for land reclamation. The disposal of the dry sand and fines resulting from this invention is environmentally preferable to existing wet disposal systems.




The substantially solids-free overhead stream flows from the hot gas clean-up through line


713


to the in-out heat exchanger


715


. The in-out heat exchanger


715


is an indirect heat exchanger wherein heat is transferred from the overhead stream to a portion of the hydrogen mixture exiting compressor


732


via conduit


733


. The heated hydrogen mixture is conveyed via a conduit line


734


to the fired heater


735


. The cooled overhead stream exits the in-out heat exchanger


715


through line


716


.




The overhead stream in line


716


enters condenser


717


where condensable vapors and gases are condensed. The overhead stream exits the condenser


717


in line


718


at a temperature of about 100° F. and passes to a first separator


719


where sour water is purged from the overhead stream via line


786


. The overhead stream, now purged of sour water, passes to a second separator


721


via conduit line


720


where a small vapor letdown stream is separated from the overhead stream and flows through line


722


to fired heater


735


. Also, carbon compounds C


3


and above are condensed and removed from the separator


721


through flow line


790


as a light substantially sulfur-free synthetic crude oil product stream comprising a mixture of naphtha and gas oils having an A.P.I. gravity of approximately 33.5. The crude oil product stream in conduit line


790


flows to storage and shipping. The remaining fluid in the separator


721


, including recycle hydrogen, is at a temperature of about 100° F. and 480 psi pressure and discharges from the separator


721


as a stream in line


723


to a scrubbing system. The scrubbing system typically comprises at least one amine absorption column


724


where sulfur components, for example, hydrogen sulfide and sulfur dioxide gases, are absorbed and discharged through line


744


from regenerator


743


. A sulfur recovery system can be used to recover sulfur from the sulfur components.




The absorber


724


can comprise, for example, a counter current circulating ethanol amine solution in intimate contact with the remaining overhead stream. The remaining fluid stream can comprise gases such as, for example, H


2


S, CO


2


, SO


2


, NH


3


, recycle hydrogen, and C


1


and C


2


hydrocarbons. H


2


S, CO


2


, SO


2


, and NH


3


are removed from the remaining fluid stream by the absorber


724


. Remaining hydrogen, C


1


and C


2


hydrocarbons form the recycle hydrogen mixture and flow through line


725


to compressor


732


.




The rich amine solution having absorbed H


2


S, CO


2


, SO


2


and NH


3


is discharged from the absorber


724


through line


740


and flows through an amine heat exchanger


741


. In the amine heat exchanger


741


the rich amine solution is heated by exchange with hot amine solution in line


750


which is returning from amine regenerator


743


to the absorber


724


. The heated rich amine solution flows through line


742


and enters the top of the amine regenerator


743


. Absorbed acid gases are stripped from the rich amine solution by further heating the rich solution using steam from a steam reboiler


745


Heat for the reboiler


745


is supplied by steam from the fired heater


735


steam recovery system.




Lean amine solution is discharged from the regenerator


743


in line


748


and is circulated by an amine circulation pump


749


through amine exchanger


741


and amine cooler


752


to the top of the amine absorber


724


.




Recycle hydrogen, and C


1


and C


2


hydrocarbons flow through line


725


to compressor


732


and are mixed with make up fresh hydrogen in line


725


A at a pressure of 450 psi and a temperature of about 100° F. The recycle gas stream is also at a pressure of 450 psi, which is the lowest pressure in the system. The compressor


732


is driven by a high pressure steam turbine


763


. High pressure steam supply in line


762


comes from the fired heater steam system at 900 to 1500 psi and a temperature of 800° F., which is super heated by 200° F. in the fired heater


735


. Exhaust steam in line


764


is condensed in condenser


765


and along with make up water is fed to the fired heater


735


for preheating and reuse as boiler feed water make up.




The compressor


732


pressurizes the recycle hydrogen mixture and make-up hydrogen from 450 psi to approximately 670 psi and 187° F. and discharge the hydrogen mixture into line


733


. A portion of the hydrogen mixture in line


733


is the first hydrogen mixture and is delivered to heat exchanger


754


via line


733


A. Another portion of the hydrogen mixture in line


733


is the second hydrogen mixture and is delivered to the in-out heat exchanger


715


.




The heat exchanger


754


cools the first hydrogen mixture from about 187° F. to 100° F. A portion of the first hydrogen mixture in line


757


flows into line


756


and to a C


1


and C


2


hydrocarbon pressure swing adsorption (“PSA”) system


755


. The PSA system helps to maintain the C


1


and C


2


hydrocarbon level in the first and the second hydrocarbon mixture at about 2% -3%. C


1


and C


2


hydrocarbon purged from the first hydrocarbon mixture is discharged through line


758


and combined with the gas in line


22


which is delivered to the fired heater


735


. Purified hydrogen produced by the PSA


755


flows through line


756


A and back to the suction of compressor


732


via line


725


.




The second hydrogen mixture is preheated to 875° F. in the in-out heat exchanger


715


by the overhead stream at 935° F. Preheated air conveyed through feed line


783


is combusted with fuel in the fired heater


735


and elevates the temperature of the second hydrogen mixture that is conveyed through line


734


from in-out heat exchanger


715


. The fuel that is combusted is obtained from the natural gas line


759


and purge gas line


722


. The hydrogen mixture circulates through the fired heater


735


and exits through line


736


. The second hydrogen mixture provides the heat required to maintain reaction in the reactor


705


.




Waste heat from the radiant section of direct fired heater


735


is recovered in convection sections


735


A,


735


B and


735


C. Steam and water are discharged from a steam drum


760


into the fired heater


735


. Heated steam is returned to the drum via line


773


. Steam separated from water in drum


760


is discharged into line


761


and introduced into convection section


735


A where the steam temperature is raised from about 596° F. to about 800° F. After passing through convection section


735


A, the super heated, high pressure steam is conveyed through line


762


to drive the steam turbine


763


. Reduced temperature and pressure steam from turbine


763


is conveyed to steam condenser


765


and the condensate recirculated via line


767


. The flow from pump


766


A is conveyed through line


767


and combined with make-up water. The water being conveyed in line


767


is introduced into convection section


735


C, heated and discharged through line


736


for further processing, such as aeration.




The following table shows material flows and operating conditions an operating reactor system.



















FLUIDIZED BED REACTOR:








Reactor (fluidized bed) Temperature




950° F.






Reactor (fluidized bed) Pressure




600




psi






H


2


Recycle Ratio




21.09






Catalyst Flow Rate into Reactor




1255.07




lbs/hr






Tar Sand Flow into Reactor




2520




tons/hr






Tar Sand Feed Inlet Temperature




50° F.






Hydrogen Mixture Flow Rate into Reactor




60.4




MMSCF/hr






Hydrogen Mixture Gas Inlet Temperature




1500° F.






ROTARY COOLERS:






Air Temperature at Intake




50° F.






Air Temperature (exiting)




623° F.






Sand Entering Temperature




950° F.






Sand Exiting Temperature




665° F.






IN-OUT HEAT EXCHANGER:






Overhead Stream Entering Volumetric




58.31




MMSCF/hr






Flow Rate






Overhead Stream Entering Temperature




950° F.






Overhead Stream Exiting Temperature




516° F.






Hydrogen Mixture Entering Flow Rate




60.4




MMSCF/hr






Hydrogen Mixture Entering Temperature




185° F.






Hydrogen Mixture Exiting Temperature




875° F.






FIRED HEATER:






Fuel Consumption (natural gas eqivalent)




1.2




MMSCF/hr






Vapor Let-Down & PSA Off Gas Fuel Supply




0.56




MMSCF/hr






(natural gas equivalent)






Make-up Fuel Supply




0.64




MMSCF/hr






Combustion Air Entering Flow Rate




26.59




MMSCF/hr






(@ 65% excess)






Steam Production Rate (@ 1500 psi)




228,996




lbs/hr






Hydrogen Mixture Entering Flow Rate




60.4




MMSCF/hr






Hydrogen Mixture Entering Temperature




875° F.






Hydrogen Mixture Exiting Temperature




1500° F.






COMPRESSOR:






Power Required From Turbine




40,148




h.p.






Steam Flow Rate to Turbine




228,996.1




lbs/hr






Steam Pressure Entering Turbine




1500




psi






Steam Temperature Entering Turbine




800° F.






(200° F. superheat)






Hydrogen Mixture Entering Flow Rate




60.7




MMSCF/hr






Hydrogen Mixture Compressor Entering




100° F.






Temperature






Hydrogen Mixture Compressor Entering




450




psi






Pressure






Hydrogen Mixture Compressor Exiting




185° F.






Temperature






Hydrogen Mixture Compressor Exiting




670




psi






Pressure






PRODUCT CONDENSER/SEPARATOR:






Product Fluid Stream Entering Flow Rate




58.3




MMSCF/hr






Product Fluid Stream Entering Temperature




516° F.






Recycle Hydrogen Mixture Exiting




100° F.






Temperature






Synthetic Crude Oil Flow Rate




1255




bbl/hr






AMINE SYSTEM:






Amine Recirculation Flow Rate




50,400




lbs/hr






Ammonia Production




1478




lbs/hr






Elemental Sulfur Production




17260




lbs/hr














While particular embodiments of the present invention have been illustrated and described herein, the present invention is not limited to such illustrations and descriptions. It is apparent that changes and modifications may be incorporated and embodied as part of the present invention within the scope of the following claims.



Claims
  • 1. A process for producing oil from a substantially dry oil bearing feed wherein said feed is tar sand or oil shale, comprising the steps of:a. introducing said feed in a fluidizable form into a fluidized bed reactor; b. introducing a fluidizing medium into the fluidized bed reactor, said fluidizing medium including at least hydrogen; c. fluidizing said introduced feed with said fluidizing medium in the reactor to form a fluidized bed; d. continuously reacting said feed with substantially only hydrogen in the fluidized bed reactor at a temperature of at least 900° F.; e. continuously discharging a product stream and spent solids from said fluidized bed reactor.
  • 2. The process of claim 1 further comprising the step of reducing the size of said feed to produce a fluidizable feed, prior to the feeding step.
  • 3. The process of claim 2 wherein said feed is tar sand.
  • 4. The process of claim 2 wherein said feed is shale.
  • 5. The process of claim 3 wherein the tar sand is crushed to 1 inch or less size pieces.
  • 6. The process of claim 1 wherein the introducing step a) comprisesinjecting the feed adjacent a bottom end of the reactor and the discharging step e) comprises discharging said spent solids adjacent a top end of said reactor.
  • 7. The process of claim 3 wherein the fluidizing medium contains substantially only hydrogen and the hydrogen is introduced into the reactor at a rate that exceeds the minimum required for complete tar sand reaction with hydrogen by a factor of between 15 and about 26.
  • 8. The process of claim 7 wherein the fluidized bed a temperature and the fluidizing hydrogen entering the reactor has a temperature, wherein the fluidizing hydrogen temperature is greater than fluidized bed temperature.
  • 9. The process of claim 8 wherein the fluidizing hydrogen temperature on entering the reactor is 1500° F.
  • 10. The process of claim 7 wherein the flow rate of hydrogen exceeds the minimum required for complete tar sand reaction with hydrogen by a factor of about 21.
  • 11. The process of claim 7 wherein the fluidizing hydrogen comprises make-up hydrogen and recycle hydrogen, and wherein the product stream includes recyclable unreacted hydrogen.
  • 12. The process of claim 11 further comprising:separating a gas mixture from the product stream, the gas mixture containing unreacted hydrogen; purifying the gas mixture to form recycle hydrogen, wherein the recycle hydrogen contains substantially only unreacted hydrogen; and returning at least a portion of the recycle hydrogen to the reactor.
  • 13. The process of claim 12 further comprising maintaining combined level of methane and ethane in the recycle hydrogen at 5% or less by pressure swing adsorption.
  • 14. The process of claim 12 wherein the unreacted hydrogen and the recycle hydrogen pressures do not fall below about 450 psi.
  • 15. The process of claim 12 further comprising the step of:admixing make-up hydrogen with the recycle hydrogen prior to returning the recycle hydrogen to the reactor.
  • 16. The process of claim 1 wherein the tar sand or shale continuously reacts with substantially only hydrogen in the fluidized bed at about 600 psi and a temperature of 900° F. to 1000° F.
  • 17. The process of claim 1 wherein the tar sand or shale reacts with substantially only hydrogen by endothermic hydrocracking or exothermic hydrogenation or both.
  • 18. A process for producing oil from a substantially dry tar sand or a substantially dry shale feed comprising:introducing said feed in a fluidizable form into a fluidized bed reactor at a first temperature; introducing a fluidizing hydrogen mixture into the fluidized bed reactor at a second temperature, wherein the second temperature is greater than said first temperature; fluidizing said fluidizable feed by contacting the feed with the fluidizing hydrogen mixture to form a fluidized bed in the fluidized bed reactor heating said feed to a third temperature by contacting the feed with the fluidizing hydrogen mixture and thereby maintaining the fluidized bed at said third temperature, wherein said third temperature is between said first temperature and said second temperature; continuously reacting the feed with substantially only hydrogen in the fluidized bed reactor at the third temperature and at about 600 psi pressure; and continuously discharging a product stream and spent solids from said fluidized bed reactor, wherein the product stream includes synthetic crude oil; wherein the third temperature is between about 900° F. and about 1000° F.
  • 19. The process of claim 18 wherein:the feed is tar sand; the first temperature is less than about 100° F.; the second temperature is about 1500° F.; and the feed has a residence time in the reactor between about 5 and about 20 minutes.
  • 20. The process of claim 19 wherein the fluidizing hydrogen mixture comprises at least about 95% hydrogen and wherein said hydrogen has a flow rate into the reactor between about 15 and about 26 times the flow rate required for complete tar sand reaction with hydrogen.
  • 21. The process of claim 20 wherein the hydrogen flow rate into the reactor is 21 times the flow rate required for complete tar sand reaction with hydrogen, and wherein the third temperature is about 950° F.
  • 22. The process of claim 20 wherein the feed is introduced into the reactor near the bottom of the fluidized bed reactor, and wherein spent solids are discharged near the top of the fluidized bed.
RELATED APPLICATIONS

This application is a continuation-in-part of application Ser. No 09/058,184 filed on Apr. 10, 1998, now U.S. Pat. No. 6,139,722 which is a continuation-in-part of application Ser. No. 08/843,178, filed on Apr. 14,1997, now U.S. Pat. No. 5,902,554, which in turn is a division of application Ser. No. 08/551,019, filed Oct. 31, 1995, now U.S. Pat. No. 5,681,452, each of which is hereby incorporated herein by reference.

US Referenced Citations (8)
Number Name Date Kind
3001652 Schroeder et al. Sep 1961
3030297 Schroeder Apr 1962
3093420 Levene et al. Jun 1963
3762773 Schroeder Oct 1973
4075081 Gregoli Feb 1978
4094767 Gifford Jun 1978
4206032 Friedman et al. Jun 1980
6139722 Kirkbride et al. Oct 2000
Continuation in Parts (2)
Number Date Country
Parent 09/058184 Apr 1998 US
Child 09/522475 US
Parent 08/843178 Apr 1997 US
Child 09/058184 US