Abstract:
There is provided a portable oil isolation and decontamination system comprising a plurality of high heat energy generators that supply high heat energy to an oil isolation and decontamination unit. Each heat energy generator comprises a chamber for gasifying used rubber tires, waste oil, coal or other combustible materials for the production of volatile gases and high energy heat. The oil extractor unit comprises a pair of parallel, elongate rotating cylinders that each rotate within a common closed housing. Oil-rich material such as oilsands, oilshale, contaminated soil or used oil is introduced into one end of each rotating cylinder and is caused to migrate to the opposite end in cascading fashion as the cylinder rotates. High energy heat from the generators is directed at the rotating cylinders to indirectly heat the oil-rich material therein to vaporize the hydrocarbons as the rotating drum migrates the oil-rich material towards its collection end. Vacuum pressure withdraws the vaporized hydrocarbons from the cylinder, and the cleaned sand or other solid material exits the collection end of each rotating cylinder and housing. The vaporized hydrocarbons condense and are collected within a forced-air condenser for recycling. An optional second stage refrigeration unit condenses any residual vaporized hydrocarbons that may be missed by the forced-air condenser.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to an apparatus for isolating oil from oilsand, oil shale, or contaminated soil, and for treating contaminated waste oil, and particularly relates to such an apparatus which is portable and the use of which is non-polluting. 
       BACKGROUND OF THE INVENTION 
       [0002]    Vast amounts of hydrocarbon fuels are stored within geological structures known as oilsands and oilshale. As more easily extracted sources of hydrocarbon fuels are depleted, increasing attention is paid to methods for extraction of oil from oilsands and oilshale. 
         [0003]    Oilsand, also known as tarsand, is a naturally occurring mixture of sand or clay and bitumen, a dense hydrocarbon. The bitumen may be processed into usable oil. Worldwide reserves of oil from oilsand are estimated to exceed 3 trillion barrels. 
         [0004]    Oil shale is a fine-grain sedimentary rock containing a solid mixture of chemical compounds, known as kerogen, from which hydrocarbons may be extracted. Processing of oil shale can convert the kerogen into usable crude oil. Global deposits of oil from oil shale are estimated to be approximately 3 trillion barrels. 
         [0005]    Various systems and methods have been attempted to remove oil from soil, sand, or other earthen materials. One of these devices is shown in U.S. Pat. No. 5,193,291, which teaches a conventional “baghouse” system wherein the contaminated soil is heated directly by a gas furnace flame. The heated soil is then discharged into the baghouse for subsequent separation and discharge. U.S. Pat. No. 5,272,833 shows a similar apparatus and process for remediating contaminated soil. This system is also a baghouse-type system. 
         [0006]    U.S. Pat. No. 5,188,041 discloses a soil remediation process comprising passing non-oxidizing heated gases over the contaminated soil at a flow rate and temperature to prevent surface drying of the contaminated soil. This system is specifically a low-temperature system, and therefore is incapable of effectively isolating oil from oilsands or oilshale. 
         [0007]    U.S. Pat. No. 5,004,486 discloses a gas cleaning system that directs the exhaust gas from the combustion chamber through a heat exchanger for cooling the gas, and into a bubbling dust separator submerged under water in order to discharge the gas directly into the water for the prevention of air pollution. 
         [0008]    U.S. Pat. No. 5,273,355 discloses a rotary drum mechanism for incinerating soil and mixing the soil with heated and dried stone aggregate for the production of asphalt paving. The gas products of combustion from the incinerator are directed into the rotary drum to be further combusted prior to direct discharge into the atmosphere. 
         [0009]    U.S. Pat. No. 5,302,118 discloses a soil remediation system comprising a rotary drum having a burner flame directed into one end of the drum, as in U.S. Pat. No. 5,193,291. In addition, as in the &#39;291 patent, the &#39;118 patent includes the baghouse-type collection mechanism for collecting dust to prevent its release into the atmosphere. 
         [0010]    Much oil is used for non-fuel purposes as well. Once used, such oil is often contaminated with metals and other contaminants which may be harmful to and inefficient for machinery. In order to reuse such contaminated oil, it is necessary to isolate the oil from the contaminants. 
         [0011]    The prior art methods of oil isolation from oil-rich materials or oil decontamination may require use of water, require addition of harmful chemicals, or cause air pollution or accumulation of toxic waste. It would be desirable to have a method and apparatus for isolation of oil from oil sand and oil shale, and for decontamination of used oil, which does not require water or addition of chemicals, and which is environmentally benign. 
       SUMMARY OF THE INVENTION 
       [0012]    According to one embodiment of the present invention, there is provided a portable oil isolation and decontamination system comprising a plurality of high heat energy generators that supply high heat energy to an oil isolation and decontamination unit. Each heat energy generator comprises a chamber for gasifying used rubber tires, waste oil, coal or other combustible materials for the production of volatile gases and high energy heat. The oil extractor unit comprises a pair of parallel, elongate rotating cylinders that each rotate within a common closed housing. Oil-rich material such as oilsands, oilshale, contaminated soil or used oil is introduced into one end of each rotating cylinder and is caused to migrate to the opposite end in cascading fashion as the cylinder rotates. High energy heat from the generators is directed at the rotating cylinders to indirectly heat the oil-rich material therein to vaporize the hydrocarbons as the rotating drum migrates the oil-rich material towards its collection end. Vacuum pressure withdraws the vaporized hydrocarbons from the cylinder, and the cleaned sand or other solid material exits the collection end of each rotating cylinder and housing. The vaporized hydrocarbons condense and are collected within a forced-air condenser for recycling. An optional second stage refrigeration unit condenses any residual vaporized hydrocarbons that may be missed by the forced-air condenser. 
         [0013]    In one of its aspects, the present invention comprises an oil isolation and decontamination apparatus for processing oil-rich material, comprising at least one heat energy generator, each heat energy generator comprising a vaporization chamber for receiving and holding waste materials to be vaporized; air supply means for supplying air under slight pressure into the vaporization chamber; fuel supply means for supplying fuel into the vaporization chamber; a volatile gas withdrawal manifold communicating with the vaporization chamber for withdrawing volatile gases from the vaporization chamber; a mixing chamber having a volatile gas inlet communicating with the volatile gas withdrawal manifold, air pressure means for introducing pressurized air thereinto, a fuel injector, and ignition means for igniting a gas fuel air mixture, and an outlet; and a combustion chamber that communicates with the mixing chamber outlet, the combustion chamber having an outlet; an oil extractor, comprising: a housing communicating with the combustion chamber outlet, whereby ignited gas/fuel/air mixture acts directly into the interior of the housing; a first rotary drum mounted for rotation about its longitudinal axis within the housing, the drum having an inlet and an outlet adjacent opposite ends thereof; a second rotary drum parallel to the first rotary drum mounted for rotation about its longitudinal axis within the housing, the drum having an inlet and an outlet adjacent opposite ends thereof; vane means within the rotary drum for migrating an introduced oil-rich material within the drum as the drum rotates; a discharge outlet formed in the housing adjacent the drum outlet for discharging the housing; and a vapor discharge outlet for withdrawing volatile vapors from the oil-rich material; and a hydrocarbon recovery system comprising: a housing having a hydrocarbon vapor inlet communicating with the vapor discharge outlet, and an exhaust gas outlet; and condensing means for condensing the hydrocarbon vapor from exhaust gases. 
         [0014]    The apparatus may be mounted on a wheeled vehicle for portability, and each heat energy generator and the hydrocarbon recovery system may be mounted on skids for portability. 
         [0015]    A dust collector may be intermediate the oil extractor and hydrocarbon recovery system for filtering the vaporized hydrocarbon and exhaust gases prior to condensation and separation of the hydrocarbons from the exhaust gases. It may also include a second-stage hydrocarbon recovery system comprising a water-cooled condensor and refrigeration heat exchanger. The apparatus may use four heat energy generators. 
         [0016]    The heat energy generator vaporization chamber and the oil extractor housing may have linings of a refractory material. The rotational longitudinal axis of each oil extractor rotary drum may be inclined relative to horizontal, with the drum inlet adjacent the higher end and the drum outlet adjacent the lower end. 
         [0017]    The vaporization chamber may have several openings in at least one wall. Each of the openings may have a diameter of between 2.5 and 3.5 inches. Ideally, there are 12 openings in the chamber. The volatile gas withdrawal manifold of each heat energy generator may be disposed at an elevation higher than the elevations of the air supply means and fuel supply means. The air supply means of each heat energy generator may be manually adjustable for controlling the amount of air being supplied into the vaporization chamber for combustion. 
         [0018]    According to another embodiment, the present invention provides use of the aforementioned apparatus to produce useable oil from an oil-rich material. The oil-rich material may be oilsand, oil shale, contaminated soil or waste oil products. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    A detailed description of the preferred embodiments is provided below by way of example only and with reference to the following drawings, in which: 
           [0020]      FIG. 1  is a schematic diagram of the oil isolation and decontamination apparatus of the present invention; 
           [0021]      FIG. 2  is a side elevation view of the first stage of the apparatus of the present invention; 
           [0022]      FIG. 3  is a top view of the first stage of the apparatus; 
           [0023]      FIG. 4  is a cross-sectional view of the first stage of the apparatus, through line  4 - 4  of  FIG. 2 ; 
           [0024]      FIG. 5  is a cross-sectional view through the second stage of the apparatus; 
           [0025]      FIG. 5B  is a cross-sectional view of another embodiment of the invention, through the second stage of the apparatus; 
           [0026]      FIG. 6  is a cross-sectional view through the rotating drum and housing; 
           [0027]      FIG. 7  is a cross-sectional view taken along lines  7 - 7  in  FIG. 5 , illustrating the interior vanes for creating the migration of the soil to be processed through the rotating drum; 
           [0028]      FIG. 7B  is an end view of the end plates of the parallel rotating drums of the apparatus; 
           [0029]      FIG. 8  is a side view of the third stage of the apparatus, specifically the condensor for condensing and reclaiming the hydrocarbon products from the volatile gases exhausted from the oil-rich material; 
           [0030]      FIG. 9  is an end view of the condensing unit of  FIG. 8 , taken along lines  9 - 9  in  FIG. 8 , and illustrating the flow of ambient temperature air through the condensing tubes; 
           [0031]      FIG. 10  is a cross-sectional view illustrating the flow of exhaust gases through the condenser, taken along line  10 - 10  in  FIG. 8 ; 
           [0032]      FIG. 11  is a schematic diagram of the optional second stage of the condensing unit, illustrating the glycol and water condensing system, the heat exchanger, and the freon refrigeration unit; and 
           [0033]      FIG. 12  is a schematic of the cooling system of the invention. 
       
    
    
       [0034]    In the drawings, one embodiment of the invention is illustrated by way of example. It is to be expressly understood that the description and drawings are only for the purpose of illustration and as an aid to understanding, and are not intended as a definition of the limits of the invention. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0035]    In the following detailed description of the invention, reference numerals are used to identify structural elements, portions of elements, or surfaces in the drawings, as such elements, portions or surfaces may be further described or explained by the entire written specification. For consistency, whenever the same numeral is used in different drawings, it indicates the same element, portion, surface and area as when first used. It should be understood that only those components having particular functional importance or that would not otherwise be identified have been assigned reference numerals. 
         [0036]    The oil isolation and decontamination apparatus of the present invention comprises a three-stage system. The first stage is a combustion chamber that combusts waste materials such as used vehicle rubber tires into high energy heat by gasification in a continuous-burn cycle. 
         [0037]    The heat energy from the first stage is fed into the second stage, which is a rotating drum that rotates within a closed chamber. The heat energy is directed into the chamber directly against the drum. The rotating drum contains the oilsand, oilshale or contaminated oil to be isolated and decontaminated by the high heat from the combustion chamber. This high heat is applied to the oilsand, oilshale or contaminated oil indirectly so that the hydrocarbons within the soil may be vaporized without burning the soil. 
         [0038]    The volatile hydrocarbon vapors are then drawn off and introduced into the third stage, which is an air-cooled condenser and hydrocarbon recovery system. This recovery system condenses the hydrocarbon vapors from the volatile exhaust gases to permit reclamation of the hydrocarbons and a clean exhaust gas to be emitted into the atmosphere. 
         [0039]    Referring now to the drawings, and initially to  FIG. 1 , the system of the present invention is shown schematically. In the schematic of  FIG. 1 , a control room  1  provides a central location for operation of the system. A horizontal trammel unit is shown at  10 . Each trammel unit includes a pair of internally rotating drums  12  for receiving the oilsand, oil shale, contaminated soil or contaminated oil (hereafter, collectively, the “oil-rich material”) to be processed into one end thereof, the material to migrate through the rotating drum during processing thereof, and be expelled from the opposite end of the trammel. Oil-rich material is placed into an auger  78 , from which it passes on a conveyor  79  to hopper  78 A a pair of adjacent augers  80 . The material exiting each auger passes into a corresponding rotating drum  12  within a common trammel unit housing  10 . 
         [0040]    Heat energy for treating the oil-rich material within the horizontal trammel unit  10  is provided by a plurality of high heat energy units  14 . Fuel for the heat energy units may be provided by used rubber tires, waste oil  11  or other fuel sources. Ignition of the fuel in the heat energy generators may be provided by a propane source  15 . These heat energy units inject heat directly into the horizontal trammel unit to act directly on the internal rotating drums  12  and, therefore, indirectly on the oil-rich material to be processed. Residual soil, sand or other solids remaining after removal of volatile hydrocarbons are deposited in a temporary storage location  17  for removal or return to their source. 
         [0041]    Volatile hydrocarbon vapors emitted from the oil-rich material as it is being processed are drawn from the horizontal trammel unit  10 , and passed using a blower  5  through a dust collector, an oil tank  7  and a water tank  9  prior to entering a forced-air condensor and recovery unit  18 . The volatile hydrocarbon vapors are condensed in the condensor and recovery unit  18  for subsequent storage in a holding tank  13  and removal, leaving the cleaned exhaust gas to be drawn through an optional second condensor unit for further condensing of any remaining hydrocarbon vapors within the exhaust gas. Each of the elements of the apparatus of the present invention will be described in detail hereinbelow in the order of progression through the system. 
         [0042]    With reference now to  FIG. 2 , the high heat energy unit  14  is shown in side elevation. The heat energy unit  14  comprises a gasification furnace  22  for receiving therein waste materials, as in used vehicle tires, for incineration by dry distillation and gasification. The gasification furnace  22  is a closed system, incorporating a sealable lid  24  that seals the contents of the furnace from the atmosphere. With the furnace  22  filled with used vehicle tires, the lid  24  is sealed down thereagainst and the ignition process is begun. 
         [0043]    A blower  26  is mounted on one side of the furnace  22  and injects air from the atmosphere into a manifold  28  for distribution to three sides and the bottom of the furnace. The manifold  28  includes a plurality of conduits  30  that direct the pressurized air into the interior of the gasification furnace  22 . One of the conduits connects the manifold  28  with an opening in the bottom of the furnace to inject air into the furnace at the approximate geometric center thereof. Another conduit  32  may direct air into a plenum  34  that carries air around to opposite sides of the furnace and injects air from the manifold into the furnace at a plurality of openings along the plenum (not shown). Another conduit  36  may direct air from the manifold  28  into the side of the furnace shown in  FIG. 2  and this conduit may include a controllable injector  38  for injecting propane directly to the interior of the furnace for initially igniting the tires therein. The propane injector  38  also includes an electric igniter for initially igniting the propane injected into the furnace. Air flow into the furnace is controlled by a plurality of valves  40  within the various conduits. 
         [0044]    The furnace also includes a plurality of openings on its sides to permit adequate oxygen flow to achieve the high temperatures desired. Ideally, at least 12 openings  41  of approximately 3 inches in diameter are provided in the sided of the furnace. The plurality of openings permits improved combustion and greater efficiency. The effect of this is to allow a wide variety of fuels to be burned. The fuels may include used rubber vehicle tires, coal, waste oil, or other materials. This increase in efficiency also permits use of smaller heat generators than in the prior art. 
         [0045]    In operation, with the gasification furnace  22  filled with used tires and sealed, the blower  26  introduces air (oxygen) into the furnace at a plurality of locations adjacent the lower portion of the furnace. Propane is injected into the furnace and ignited by the propane injector  38 , and, along with the inflow of air (oxygen) from the blower  26 , ignites the waste tires. When a sufficient operating temperature is reached, further propane is unnecessary to maintain combustion of the tires within the furnace. The inflow of air into the furnace is controlled to maintain sufficient oxygen to permit the tires and other waste material to maintain combustion in a continuous-burn mode, and gasify the waste material through dry distillation. Adequate oxygen supply is provided by a plurality of openings in the side of the furnace, as indicated in  FIG. 2 . 
         [0046]    In order to efficiently maintain a temperature of up to 3700° F. to sustain combustion and dry distillation of the waste tires, the gasification furnace  22  includes a refractory lining approximately two inches thick to accommodate greater sustained heat generation. The sealable lid  24  includes a similar refractory lining. 
         [0047]    As the gasification furnace  22  is a closed system, as the used tires combust and vaporize, volatile gases are generated within the furnace. These volatile gases are permitted to exhaust from the furnace via a plurality of openings (not shown) from the interior of the furnace into a second manifold  42 , positioned slightly above the various inlets of atmospheric air into the furnace from the blower  26 . The manifold  42  collects these volatile gases and directs them into a mixing chamber  44  for mixing with additional air (oxygen) prior to further combustion. This mixing chamber is more clearly shown in  FIGS. 3 and 4 . 
         [0048]      FIG. 3  is a top view of the first stage device of oil isolation and decontamination system, illustrating the relative positions of the furnace and the various manifolds and conduits associated therewith, and the mixing chamber and combustion chamber. As shown, the second manifold  42  directs volatile gases exhausting from the gasification furnace  22  directly into the mixing chamber  44 . The interior of the mixing chamber is best shown in  FIG. 4 . The mixing chamber comprises an outer enclosure  46 , preferably circular, and having an intermediate conduit  48  therein in essentially axial concentricity. A short robe  50  provides communication between the interiors of the second manifold  42  and the intermediate conduit  48 , so that the volatile exhaust gases from the furnace  22  are directed into the interior of the intermediate conduit  48 . An inner conduit  52  is positioned concentrically within the intermediate conduit  48 , and is connected to a second blower  54  for introducing air from the atmosphere directly into the mixing chamber  44 . 
         [0049]    Volatile gases from the furnace  22  flow through the second manifold  42 , into the interior of the intermediate conduit  48 , and directly into a combustion chamber  56 , as shown in  FIG. 4 . Pressurized air provided by the blower  54  is forced through the inner conduit  52  and exits at a location adjacent that of the volatile gases from the furnace exiting the intermediate conduit  48 . Air flow through the inner conduit  52  mixes with the volatile gases, and this gas-air mixture flows into the combustion chamber  56 . 
         [0050]    The outer enclosure  46  includes a second propane injector  58  and igniter  60 . When the system is initially started, propane is injected into the air-volatile gas mixture, and then ignited by the igniter to create combustion in the combustion chamber  56 . Once this mixture has been ignited, the propane is shut off, and the volatile gas and air mixture continues to combust in the combustion chamber. 
         [0051]    Referring again to  FIGS. 2 and 3 , the furnace, its associated manifolds, air injectors, etc., and the mixing chamber  44  and combustion chamber  56  are shown mounted on a pair of skid rails  62 . In this manner, the first stage of the apparatus of the present invention can be readily transported, along with the remaining stages, to a desired site for direct on-site processing of oil-rich material. 
         [0052]    As shown in  FIG. 1 , four high heat energy units  14 , as shown in detail in  FIGS. 2-4 . The combustion chamber  56  of each unit is attached directly into the side of the second stage of the system, specifically the horizontal trammel unit  10 . 
         [0053]    Turning now to  FIG. 5 , the horizontal trammel unit  10  is shown in vertical section. The trammel includes the internal rotating drum  12  that rotates on trunions  70  on the left and  72  on the right. The rotating drum  12  rotates concentrically about its longitudinal axis within a longitudinal insulated shell  74  into which the combustion chambers  56  from the heat energy units  14  direct their respective blasts of ignited volatile gas and air mixtures. 
         [0054]    The rotating drum  12  is essentially a closed drum, open only at one end (the right end as shown in  FIG. 5 ) for the introduction of contaminated oil-rich material thereinto, and the withdrawal of hydrocarbon vapors therefrom. In addition, the drum includes two openings adjacent the opposite end (the left end as shown in  FIG. 5 ), which permit the processed sand or other solids to drop out therefrom as the drum rotates. 
         [0055]    In operation, four respective combustion chambers  56  may be attached directly to the insulated shell  74  of the trammel unit as indicated in  FIG. 1 . Specifically, each combustion chamber  56  attaches to the shell  74  at a respective inlet  76  for injecting heat from the high heat energy units  14  directly into the annular space within the insulated shell and around the rotating drums, in order to indirectly heat the oil-rich material as the material migrates through the drum. Oil-rich material is introduced into each rotating drum via a hopper  78  and a pair of augers  80  which transport the oil-rich material directly into the interior of each drum at the right end as shown at  FIG. 5 . 
         [0056]      FIG. 6  is a vertical plan view taken on the right hand side in  FIG. 5 , and more clearly illustrates how each auger  80  introduces the oil-rich material into each rotating drum  12 . Each rotating drum  12  is supported by, and rotates on, trunnions  72  along its outside diameter. Each drum includes an externally toothed ring  82  formed therewith, and by which the drum is rotated via a drive gear mechanism  84 . A stationary cylindrical section  86  (best shown in  FIG. 5 ) is positioned within the toothed ring  82  such that the ring rotates around the cylindrical section  86 . 
         [0057]    The cylindrical section  86  is closed at one end (the right end as shown in  FIG. 5 ) by an end plate  88  which has openings therein for the auger  80  and two hydrocarbon vapor suction conduits  90 . The stationary cylindrical section  86  is supported on the platform by brace  92 . 
         [0058]    Each rotating drum  12  is supported at its opposite end (the left end as shown in  FIG. 5 ) by a hollow bushing  94  formed with the end plate  96  of the drum. The hollow bushing  94  is supported by and rotates on trunnion  70  in a customary manner. The hollow bushing provides communication between the interior of the rotating drum and a separate conduit  98  within the interior of the insulated shell. The conduit  98  is open to the interior of the shell at the upper end thereof (the right end as shown in  FIG. 5 ) when the system is operating. The function of the open conduit  98  within the trammel unit insulated shell will be explained in greater detail hereinbelow. 
         [0059]      FIG. 7  illustrates the plurality of vanes  100  within the rotating drum that cause the oil-rich material to migrate along the inner diameter of each drum as the drum rotates. The direction of migration of the oil-rich material within the drum is from right to left as shown in  FIG. 5 . As the drum rotates, these vanes function to lift individual portions of the oil-rich material and cause it to cascade and disburse as it slowly migrates from right to left within the drum. As each drum is inclined slightly downwardly at its left end, the tumbling effect of the oil-rich material within the drum caused by the vanes causes the oil-rich material to slowly migrate toward the left end of the drum, as it is being constantly rotated, heated, cascaded, agitated, and migrated by the tumbling effect of the drum. 
         [0060]    Each drum includes at least one exit opening (not clearly shown) adjacent the left end thereof that permits a certain amount of processed soil to drop therefrom with each revolution of the drum. In practice, this exit opening takes the form of a rectangular opening adjacent the drum end plate  96 . The longitudinal insulated shell  74  includes a similar opening in the bottom thereof aligned with the opening in the rotating drum so that the processed sand or other solid material may drop directly therethrough and onto a conveyor belt or similar for transportation if desired. 
         [0061]    One or more hydrocarbon vapor suction conduits  90  draw the vaporized hydrocarbons that are vaporized in the process from within the interior of each rotating drum to the third stage of the system, the hydrocarbon condensor. The vacuum pressure that draws the vaporized hydrocarbons from the oil-rich material within each rotating drum also draws a certain amount of high temperature exhaust generated by the high heat energy units  14  from the annulus around the rotating drums through the conduit  98  and hollow bushing  94  into the interior of each rotating drum in order to facilitate, by direct heat, further vaporization of the hydrocarbon contaminants within the oil-rich material. Specifically, the heat blasting from the combustion chambers  56  into the insulated shell  74  surrounds the rotating drums and directly heats the rotating drums to indirectly heat the oil-rich material therein. As this heat from the combustion chambers is under pressure, the pressure within the insulated shell  74  is permitted to escape through the separate conduit  98  and the hollow bushing  94  into the interior of the rotating drum facilitate the vaporization of the hydrocarbons from the oil-rich material. The vacuum applied at the hydrocarbon vapor suction conduits  90  draws the vaporized hydrocarbons from the interior of the rotating drums, through the dust collector  16  and into the forced-air condensor and recovery unit  18 , as shown in the schematic of  FIG. 1 . 
         [0062]      FIG. 8  is a side view of the third stage of the oil isolation and decontamination system, comprising the forced-air condensor for condensing and reclaiming hydrocarbon products from the vaporized hydrocarbon gases exhausted from the oil-rich material within the rotating drum. The forced-air condensing and recovery unit  18  comprises a closed housing  110  having a plurality of conduits (pipes)  112  passing therethrough longitudinally. This is more clearly shown in  FIGS. 9 and 10 . The housing  110  includes an inlet  114  for the introduction of the vaporized hydrocarbons and exhaust gases from the horizontal trammel unit  10 , and an outlet  116  for the exhaust gases remaining after the hydrocarbons have been condensed within the forced-air condensing unit. 
         [0063]    As best shown in  FIG. 9 , the forced-air condensing and recovery unit includes the plurality of pipes  112  passing longitudinally therethrough. Cold air flows through these pipes under pressure from a fan and shroud  118  at the opposite end of the unit (at the left end as shown in  FIGS. 8 and 10 ) to cause the vaporized hydrocarbons in the exhaust gases to condense on the outside of the pipes within the housing  110 . As shown in  FIG. 8 , the bottom of the condensing and recovery unit  18  is slopped downwardly toward the left to permit the condensed hydrocarbons to be collected and periodically drained from the collecting pan. 
         [0064]      FIG. 10  illustrates the serpentine pattern that the vaporized hydrocarbons and exhaust gases follow as the exhaust gases flow through the forced-air condensing and recovery unit. This serpentine pattern is created by a plurality of baffles  120  within the housing  110 . As can be appreciated, these baffles are vertical, and span the entire height from top to bottom within the forced-air condensing and recovery unit housing  110 . In addition, as with the high heat energy units  14 , the forced-air condensing and recovery unit  18  includes skids  122  to enable the unit to be easily transported and attached to the conduits that interconnect the various elements of the system. 
         [0065]    It should be appreciated that the forced-air condensing and recovery unit uses air at ambient temperature for condensing the vaporized hydrocarbons from the exhaust gases. In most instances, this works quite well to recover essentially all of the vaporized hydrocarbons from the exhaust gases. In unusually warm climates, however, air at ambient temperature may not be adequate to fully condense all of the vaporized hydrocarbons from the exhaust gases. In these instances, a second stage in the condensing process may be utilized. This second stage is shown schematically in  FIG. 11 , and can be referred to as a chiller. 
         [0066]    Exhaust gases from the forced-air condensing and recovery unit  18  that still contain trace amounts of vaporized hydrocarbons are drawn through a closed collection unit  130  at inlet  132 . The collection unit  130  includes a series of condensing coils, shown schematically at  134 . The vaporized hydrocarbons pass through the condensing coils  134  and are condensed on the coils and collect at the bottom of the collection unit  130  for periodic removal. The remaining clean exhaust gases exit the closed collection unit at the outlet  136  to be exhausted to atmosphere. 
         [0067]    The condensing coils  134  communicate directly with a heat exchanger  140  to transfer heat from the condensing hydrocarbons to the heat exchanger. These condensing coils  134  carry a mixture of 30% glycol and water, maintained at approximately 30° F. The heat exchanger  140  transfers heat from the glycol and water mixture to a conventional refrigeration circuit  142  that draws heat and distributes it to atmosphere in a conventional manner. 
         [0068]    Whether the oil isolation and decontamination system of the present invention utilizes only the forced-air condenser shown in  FIGS. 8-10 , or both the forced-air condenser and the refrigeration unit chiller of  FIG. 11 , exhaust gases are drawn through the system by an exhaust fan  144  located at the point of exhaust to the atmosphere. In either configuration, the exhaust fan provides the vacuum to draw the vaporized hydrocarbons through the system for condensation and reclamation, and exhausts the cleaned gases to atmosphere. 
         [0069]    It is to be noted that the apparatus of the present invention provides a means of isolation and decontamination of oil from oilsand, oil shale, or other oil-rich material without the use of water or the addition of chemicals which may be harmful to the environment. 
         [0070]    From the foregoing, it will be seen that this invention is one well adapted to attain all of the ends and objectives herein set forth, together with other advantages which are obvious and which are inherent to the apparatus. It will be understood that certain features and sub-combinations are of utility and may be employed with reference to other features and sub-combinations. This is contemplated by and is within the scope of the claims. As many possible embodiments may be made of the invention without departing from the scope of the claims. It is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense. It will be appreciated by those skilled in the art that other variations of the preferred embodiment may also be practised without departing from the scope of the invention.