Mobile facility and process for mining oil bearing materialsand recovering an oil-enriched product therefrom

CA 02332207 2001-10-02

MOBILE FACILTY AND PROCESS FOR MINING OIL BEARING MATERIALS AND RECOVERING AN OIL-ENRICHED PRODUCT THEREFROM

Tar sands are deposits of loose sand or partially consolidated sandstone which are saturated with highly viscous bitumen. Tar sand is a common form of oil bearing material. It is also sometimes called bituminous sand or oil sand. The world’s largest known deposits of tar sands are located in Canada on the banks of the Athabasca River in northeastern Alberta. The Athabasca tar sands are estimated to contain some 300 billion barrels of bitumen heavy oil. Of this total, it is estimated that some 80 billion barrels are accessible for recovery through surface mining methods.

Oil produced from the bitumen in tar sands is commonly referred to as synthetic crude oil. The only commercial projects for synthetic oil production from tar sands are being carried out in the Athabasca region. A project for a typical 100,000 barrel per day bitumen production facility is currently estimated to cost over 1 billion dollars to build using conventional technologies. Such a project would also cost over $5 dollars per barrel to operate and would have significant environmental impacts.

Conventional technologies presently used for commercial operation of bitumen recovery from tar sand were developed in the mid-sixties and, until now, have not changed dramatically. They currently involve surface mining to extract thick tar sand deposits found near the surface. Before the actual mining operations begin, the mine area is dewatered and overburden is removed from its surface. Earth moving equipment is used to strip and stockpile the overburden. The overburden will be later removed and disposed of with the same equipment. Meanwhile, construction of tailings pond starter dikes is undertaken using appropriate stripped overburden. Excavation was traditionally achieved using a bucketwheel or drag line excavation method. More recently, large shovels and trucks are used. Heavy truck haul roads for the transport of overburden and tar sand ore are constructed, often employing scarce granular resources. The mining of tar sand ore can begin afterwards. After mining, the tar sand ore is hauled to a preparation facility where

CA 02332207 2001-10-02 it is crushed and mixed with water to form a slurry. The slurry is then pumped into pipelines and sent to a central processing plant.

Generally, a conventional processing plant removes bitumen from the slurry using a bitumen flotation method. Such method involves using hot water for slurrying. Bitumen froth is floated by way of thickener type vessels and air induced flotation cells. The bitumen froth contains a concentrated amount of bitumen. This oil enriched product is sent to another plant where it will be upgraded to synthetic crude oil.

Since the bitumen is typically only about 7 to 12% of the total ore mass removed from the mine face, tailings are produced and are transported in massive quantities throughout the process. In conventional recovery operations, these tailings are ultimately transported out of the processing plant by hydro-transport methods and disposed in immense tailing ponds, where the fine suspended solids are allowed to settle by gravity. Over the ensuing years, fine particles in the water settle to a point where water can be removed and the solids sludge from the tailing ponds can be rehandled and mixed with coarse tailings in the manufacture of consolidated tailings. It is only then that tailing ponds can be remediated and eventually reforested. Meanwhile, tailing pond dikes need to be continuously constructed since the process generates waste products faster than the settling rate in the tailings ponds can clarify.

Conventional recovery technologies thus have many drawbacks. One of the major ones is that they require transport of massive quantities of materials such as tailings, tar sand ore and water over very long distances. Tailings ponds also have a major impact on the environment and are a concern to governments and the public.

Operating a conventional recovery process is very costly because of all the required transport equipment, support facilities, apparatuses, personnel and energy required to undertake all tasks. As a result, the recovery of bitumen from tar sand ore is a risky venture because profits can be easily offset by the very

CA 02332207 2001-10-02 large fixed and variable operating costs. Projects are viable only when the price of crude oil is relatively high.

Overall, conventional technologies for mining and exploiting deposits of oil bearing materials are limited in their applicability, environmental acceptability, cost and therefore, in their overall efficacy.

The present invention is concerned with providing a suitable alternative to conventional technologies and applies to various oil bearing materials, such as tar sand.

The present invention will now be described with references to the appended figures, in which:

FIG. 1 is a schematic diagram showing an example of the process in accordance with a possible embodiment of the present invention.

FIG. 2 is a side elevation view of the exterior of a mobile facility in accordance with a possible embodiment of the present invention.

FIG.3 is a side elevation view showing the interior of the mobile facility of FIG. 2.

FIG. 4 is a top view taken along line 4-4 in FIG. 3.

Referring to FIG. 1, there is shown an example of a process according to a preferred embodiment of the present invention. It should be noted that the reference numerals in the hexagons refer only to a stream number for Table 1 at the end of the present description. The numerals outside the hexagons are the reference numerals used throughout the present description.

The present invention is used for mining oil bearing materials, such as tar sand, and recovering an oil-enriched product therefrom, in particular bitumen. Preferably, the oil bearing material is extracted using an open pit technique,

CA 02332207 2001-10-02 whereby the material is mined with suitable mining equipment in an opened mine area. The mine area is previously prepared, which involves known tasks such as mine dewatering, muskeg removal and stacking for future use, and overburden stripping and storage for later re-deposition in the mine face (M), whenever appropriate.

The process of FIG. 1 is preferably carried in a mobile facility (10), such as the one shown in FIGS. 2 to 4. The mobile facility (10) preferably comprises a supporting platform (10a) on which are mounted the components required to carry out the recovery process. Most of these elements are enclosed in a space above the platform (10a). It should be noted that the illustrated mobile facility (10) is only one possible example and other embodiments are possible.

Referring back to FIG. 1, mining of an oil bearing material from the mine face (M) is carried out using at least one mining head (12). The mining head (12) is preferably located at the front of the mobile facility (10). There are many kinds of possible mining heads (12). One of them is a mining head (12) using rotating cutters (12a), which embodiment was found to be very suitable for oil bearing materials.

Once mined, the oil bearing material is preferably carried inside the mobile facility (10) using a first conveyor (14). In the mobile facility (10) illustrated in FIGS. 2 to 10, the first conveyor (14) is preferably a pan conveyor.

Referring back to FIG. 1, the oil bearing material is discharged at the end of the first conveyor (14) over a screen (16), preferably a scalping grizzly or any suitable equivalent, in order to remove oversized ore lumps. If necessary, these oversized ore lumps could be fed into a crusher to reduce their size under the maximum limit required for slurrying. Alternatively, they can be dropped on the ground beneath the mobile facility (10) or even bypassed and added directly to the tailings that are produced at the end of the process. Similarly, mined materials can be diverted to the tailings using a bypass path, such as a chute, when they are not suitable for

CA 02332207 2001-10-02 processing. This would be the case if, for example, oil is not present in worthwhile quantities at a particular location in the mine.

Also in FIG.1, the oil bearing material that has passed through the screen (16) preferably falls onto a second conveyor (18), more preferably a pipe conveyor. A pipe conveyor is a conveyor where the sides of the belt are wrapped into an overlapping engagement and the belt forms a pipe enclosing the oil bearing material until it reaches the discharge end, where the pipe opens into a conventional conveyor shape and the oil bearing material is discharged thereafter. Preferably, a tramp magnet (20) is held close to the surface of the first conveyor (14) to remove iron debris, if any. The second conveyor (18) preferably discharges the oil bearing material into a crusher (22) located above a slurry feed tank (30). Alternatively, it can also discharge the oil bearing material directly into the slurry feed tank (30).

It should be noted that the screen (16) and the crusher (22) may be optional. For instance, the mining head (12) may efficiently grind the oil bearing material on the mine face (M) so that subsequent crushing thereof is not required. However, in most cases, it is desirable to preprocess the raw mined material to eliminate particles having a size above a maximum limit required for slurrying and which may otherwise inflict operating difficulties or damage to the equipment.

The oil bearing material supplied in the slurry feed tank (30) is mixed with a suitable solvent to form a slurry. The nature of the solvent depends on the kind of oil bearing material being processed. In the case of tar sand, the solvent could be water and the water is at least of equal weight with the oil bearing material. The temperature of the supplied water is such that the slurry preferably has a temperature ranging from about 80° to 160° Fahrenheit (26°C to 72°C) in order to promote the separation of the bitumen from the other constituents in the slurry.

The slurry in the slurry feed tank (30) is preferably agitated continuously using a mixer (32) or any other suitable device to achieve the same purpose.

CA 02332207 2001-10-02

From the slurry feed tank (30), the slurry is pumped or otherwise conveyed into the inlet of a first hydrocyclone (40). It should be noted that the term «hydrocyclone» also includes the case where two or more hydrocyclones are disposed in parallel. A hydrocyclone is essentially a device wherein the centrifugal force created by the swirling action of the fluid therein is used to separate a lighter portion of its content from a heavier portion thereof. The lighter portion is referred to as the «overflow portion» while the heavier portion is referred to as the «underflow portion». The overflow portion flows through an overflow outlet located at or near the top. The underflow portion flows through an underflow outlet at or near the bottom.

The slurry in the slurry feed tank (30) is preferably brought to the inlet of the first hydrocyclone (40) using a vertical submersible feed pump (34). The pump (34) has an inlet in the slurry feed tank (30) and an outlet in fluid communication with the inlet of the first hydrocyclone (40). The use of this particular kind of pump is preferred since it permits arrangements that eliminate the need for valves which are generally problematic in slurry service.

The overflow portion flowing through the overflow outlet of the first hydrocyclone (40) is oil enriched. This oil-enriched product is then either sent to another separation process in the mobile facility (10), or sent directly as such into a product pipeline (36). The product pipeline (36) is used to send the oil-enriched product to an off-site processing plant where it will ultimately be upgraded into synthetic crude oil. Pumps are located at strategic locations to convey the oil-enriched product through the pipeline (36).

In the embodiment illustrated in FIG. 1, the process comprises the step of removing the solvent from the oil-enriched product, thus producing a further concentrated oil-enriched product before the product is sent out of the mobile facility (10). One of the advantages of removing solvent from the oil-enriched product is that it can immediately be recycled back into an earlier stage of the process, thereby lowering the amount of fresh or recycled solvent that needs to be supplied to the mobile facility (10) and the thermal energy to be furnished. The solvent is removed using a product separator, preferably a decanter (46), as illustrated in FIG. 1. Alternatively, the product separator could be another

CA 02332207 2001-10-02 hydrocyclone in which the overflow portion is the further concentrated oil-enriched product, and the underflow portion contains the solvent to recycle.

The underflow portion of the first hydrocyclone (40) is a dense slurry containing mainly solvent and solids. However, it still contains some amount of kerogen, bitumen or other oil-carrying product which could be recovered by further processing the slurry. If this is not desired, the underflow portion is then directly vacuum filtered in order to remove solvent therefrom.

The vacuum filtering is preferably achieved by a vacuum belt filter system (48) or an equivalent thereof. As illustrated in FIG. 1, the vacuum filter (48) preferably comprises a porous endless conveyor belt (48a) under which is located a vacuum chamber (48b). The vacuum may be provided by a vacuum pump (48c). The slurry to filter is continuously laid on the conveyor belt (48a) at one end and the solvent is removed therefrom as it is conveyed towards the discharge end. The solvent is brought into the vacuum chamber (48b) and is thereafter sent with the retrieved air into an air/liquid separator (48d) through corresponding lines. The solvent removed from the underflow portion is recycled back into an earlier stage of the process. The air/liquid separator (48d) preferably comprises an air outlet in fluid communication with the vacuum pump (48c). Preferably, the vacuum pump (48c) comprises an air outlet in fluid communication with a region in the vicinity of the belt (48a) of the vacuum filter (48). This has the advantage of conserving heat when the mobile facility (10) operates in cold weather.

Substantially dewatered tailings (100) come out of the vacuum filter system (48). These tailings are said to be substantially «dewatered» since most of the solvent is removed therefrom and only enough solvent remains to provide geotechnical strength of the tailings (100) for stability of the deposition. The dewatered tailings (100) preferably fall on a tailings stacker (102), which is for instance a pipe conveyor arranged as a bridge and which conveys the tailings (100) out of the mobile facility (10) for deposit in an adjacent area. The tailings (100) may be used to backfill the mine trenches.

CA 02332207 2001-10-02

The tailings stacker (102) is preferably in the form of a track-supported bridge-type pipe conveyor. Other variants are also possible.

Referring again to FIG. 1, the underflow portion coming out of the first hydrocyclone (40) preferably falls into a corresponding sump (42). A vertical submersible feed pump (44) is preferably located in the sump (42). This pump (44) has an inlet in the sump (42) and an outlet in fluid communication with the inlet of a second hydrocyclone (50). The second hydrocyclone (50) is used to separate the content of the first sump (42) into an overflow portion and an underflow portion.

In the second hydrocyclone (50), the overflow portion flows out through a corresponding overflow outlet and is preferably sent back to the slurry feed tank (30). The underflow portion of the second hydrocyclone (50) flows out through a corresponding underflow outlet and into a second sump (52).

The embodiment illustrated in FIG. 1 further comprises a third hydrocyclone (60). The content of the second sump (52) is then supplied to the inlet of the third hydrocyclone (60), preferably using a corresponding vertical submersible feed pump (54). The third hydrocyclone (60) separates the content of the second sump (52) into an overflow portion and an underflow portion. The overflow portion of the third hydrocyclone (60) flows out through an overflow outlet which is preferably made in fluid communication with the first sump (42). This allows a countercurrent washing circuit to be created. The underflow portion of the third hydrocyclone (60) flows out of an underflow outlet and goes into a third sump (62).

It is further possible to use a fourth or even more hydrocyclones in the process. If a fourth hydrocyclone is used, its overflow outlet would be in fluid communication with the inlet of the third hydrocyclone (60). In other words, the overflow portion coming out of a fourth hydrocyclone would be sent to the second sump (52). The general rule is that the overflow portion of an hydrocyclone, beginning with the third hydrocyclone (60), is preferably used to repulp the sump below the

CA 02332207 2001-10-02 hydrocyclone which is two stages earlier. It is the underflow portion of the last of the hydrocyclones which is sent to the vacuum filter system (48).

If necessary, the content of the second sump (52) or the third sump (62) can be diluted with recycled solvent, for instance solvent coming from the decanter (44) or another source. This may be necessary since the concentration of solids increases from one hydrocyclone to another.

In the embodiment illustrated in FIG. 1, the third sump (62) is the final station before the vacuum filtering. A flocculant agent is advantageously added into the third sump (62) before its content is sent to the vacuum filter system (48). The flocculent agent allows fine particles to agglomerate, making the vacuum filtering more effective. The flocculant agent is preferably stored in an agitated tank (64) and supplied into the third sump (62) using a corresponding pump (66). The content of the third sump (62) is preferably sent to the vacuum filter system (48) using a vertical submersible feed pump (68) having an inlet in the sump (62) and an outlet in fluid communication with the inlet of the vacuum filter system (48).

As can be appreciated, the process only requires the use of a relatively small amount of fresh solvent. Fresh solvent is added into the process to replace residual solvent in the oil-enriched product coming out of the product pipeline (36) and in the tailings (100). This fresh solvent preferably comes through a fresh solvent supply line (70) connected to a suitable source. Most of the fresh solvent is preferably sent into the slurry feed tank (30) following a network of lines. Some of this solvent can also be combined with recycled solvent. It can further be used to dilute the contents of some of the sumps. In the embodiment of FIG. 1, some of the fresh solvent could be sent into the second sump (52) if necessary.

The fresh solvent supply line (70) advantageously comprises a hose and a hose reel (72). The hose is preferably in the form of a flexible line to be connected to a service facility outlet. Similarly, the product pipeline (36) advantageously comprises a flexible hose and a hose reel (72) to be connected to an appropriate outlet. The product hose reel (74) and solvent supply hose reel are preferably

CA 02332207 2001-10-02 mounted on transport crawler tracks and/or wheels. Electrical powerlines (not shown) could be mounted the same way. All of these flexible connections provide relocatable umbilical connections for an efficient operation of the mobile facility (10). Of course, other arrangements are possible, including the design of a mobile facility having fully independent systems. In that case, the power could be supplied using generators while the fresh solvent and oil-enriched products are stored in corresponding tanks to be serviced from time to time.

A froth skimmer (76) is preferably provided in the slurry feed tank (30) in order to collect a froth which usually forms over the slurry. This primary froth is advantageously oil-enriched and can be directly combined with the stream coming out of the overflow outlet of the first hydrocyclone (40). In the embodiment of FIG. 1, the froth skimmer (76) comprises a pump (78) having an outlet in fluid communication with the inlet of the decanter (44). Similarly, froth skimmers can be employed on each of the hydrocyclone underflow sumps and the froth recovered combined with the overflow outlet of the first hydrocyclone (40).

The mobile facility (10) is preferably moved using a ground-engaging undercarriage (80), and is preferably controlled by an operator installed at the front section. This ground-engaging undercarriage (80) supports the mobile facility (10) and repositions it as the mining head or heads (12) advances. The undercarriage (80) preferably comprises motorized crawler tracks or wheels. In the embodiment of FIGS. 1 to 4, the undercarriage (80) comprises motorized crawler tracks, which are preferred since they are generally more suitable for moving very large and heavy equipment over unpaved surfaces.

Heat is preferably provided to the system using the fresh solvent. Hence, the fresh solvent is supplied in a heated state so as to provide heat for the slurry in the slurry feed tank (30) or any other suitable location. Alternatively, or in addition to the heated fresh solvent supply, a solvent heater (not shown) can be used in order to increase the temperature of the solvent or the slurry in the process. A further alternative is that the solvent in the oil-enriched product be recovered in a remote processing plant, heated at that location with any available heating media, such as waste heat, and then returned to the mobile facility (10) via flexible hoses together

CA 02332207 2001-10-02 with, or separate from, fresh solvent. However, this is essentially a matter for capital and operating cost optimization with the fixed plant infrastructure on a site specific basis.

EXAMPLE

The following Table 1 is an example of a material balance using a process as illustrated in FIG. 1 for recovering bitumen from tar sand. The various stream numbers are identified throughout the drawing with the reference numerals in hexagons.

<img file="CA2332207C_D0001.tif" />

CA 02332207 2001-10-02

TABLE 1 : MATERIAL BALANCE

<td> Stream No.</td><td></td><td> 1</td><td> 2</td><td> 3</td><td> 4</td><td> 5</td><td> 6</td><td> 7</td>

<td> Bitumen</td><td> t/h</td><td> 240</td><td> 1</td><td> 124</td><td> 37</td><td> 49</td><td> 34</td><td> 15</td>

<td> Water</td><td> t/h</td><td> 100</td><td> 885</td><td> 2228</td><td> 669</td><td> 2194</td><td> 1536</td><td> 658</td>

<td> Solids</td><td> t/h</td><td> 1660</td><td> 91</td><td> 1919</td><td> 1688</td><td> 1903</td><td> 228</td><td> 1675</td>

<td> Total</td><td> t/h</td><td> 2000</td><td> 978</td><td> 4271</td><td> 2394</td><td> 4146</td><td> 1798</td><td> 2348</td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td> Bitumen</td><td> wt%</td><td> 12.0</td><td> .01</td><td> 2.9</td><td> 1.9</td><td> 1.2</td><td> 1.9</td><td> 0.6</td>

<td> Water</td><td> wt%</td><td> 5.0</td><td> 90.6</td><td> 51.3</td><td> 27.9</td><td> 52.9</td><td> 85.4</td><td> 28.0</td>

<td> Solids</td><td> wt%</td><td> 83.0</td><td> 9.3</td><td> 44.9</td><td> 70.5</td><td> 45.9</td><td> 12.7</td><td> 71.3</td>

<td> Heat capacity</td><td> Btu/lb/F</td><td> 0.271</td><td> 0.924</td><td> 0.629</td><td> 0.440</td><td> 0.633</td><td> 0.886</td><td> 0.440</td>

<td> Specific gravity</td><td></td><td> 2.24</td><td> 1.06</td><td> 1.41</td><td> 1.83</td><td> 1.41</td><td> 1.09</td><td> 1.84</td>

<td> Total Volume</td><td> USGPM</td><td> 3568</td><td> 3694</td><td> 12124</td><td> 5231</td><td> 11716</td><td> 6613</td><td> 5107</td>

<td> Temp</td><td> °F</td><td> 32</td><td> 94</td><td> 78</td><td> 78</td><td> 85</td><td> 85</td><td> 85</td>

<td> Stream No.</td><td> 8</td><td> 9</td><td> 10</td><td> 11</td><td> 12</td><td> 13</td><td> 14</td>

<td> Bitumen</td><td> 16</td><td> 11</td><td> 5</td><td> 5</td><td> 0</td><td> 5</td><td> 87</td>

<td> Water</td><td> 2179</td><td> 1525</td><td> 654</td><td> 656</td><td> 2</td><td> 273</td><td> 1560</td>

<td> Solids</td><td> 1792</td><td> 215</td><td> 1577</td><td> 1577</td><td> 0</td><td> 1577</td><td> 230</td>

<td> Total</td><td> 3987</td><td> 1752</td><td> 2235</td><td> 2237</td><td> 2</td><td> 1854</td><td> 1877</td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td> Bitumen</td><td> 0.4</td><td> 0.7</td><td> 0.2</td><td> 0.2</td><td> 0.0</td><td> 0.3</td><td> 4.6</td>

<td> Water</td><td> 54.7</td><td> 87.1</td><td> 29.2</td><td> 29.3</td><td> 100.0</td><td> 14.7</td><td> 83.1</td>

<td> Solids</td><td> 44.9</td><td> 12.3</td><td> 70.5</td><td> 70.5</td><td> 0.0</td><td> 85.0</td><td> 12.3</td>

<td> Heat capacity</td><td> 0.646</td><td> 0.897</td><td> 0.449</td><td> 0.449</td><td> 0.997</td><td> 0.336</td><td> 0.871</td>

<td> Specific gravity</td><td> 1.40</td><td> 1.08</td><td> 1.81</td><td> 1.81</td><td> 1.00</td><td> 2.18</td><td> 1.09</td>

<td> Total Volume</td><td> 11399</td><td> 6475</td><td> 4924</td><td> 4932</td><td> 8</td><td> 3394</td><td> 6900</td>

<td> Temp</td><td> 90</td><td> 90</td><td> 90</td><td> 90</td><td> 80</td><td> 90</td><td> 78</td>

CA 02332207 2001-10-02

<td> Stream No.</td><td> 15</td><td> 16</td><td> 17</td><td> 18</td><td> 19</td><td> 20</td><td> 21</td>

<td> Bitumen</td><td> 235</td><td> 0</td><td> 0</td><td> 151</td><td> 0</td><td> 0</td><td> -</td>

<td> Water</td><td> 109</td><td> 383</td><td> 0</td><td> 293</td><td> 280</td><td> 383</td><td> -</td>

<td> Solids</td><td> 83</td><td> 0</td><td> 0</td><td> 61</td><td> 0</td><td> 0</td><td> -</td>

<td> Total</td><td> 427</td><td> 383</td><td> 0</td><td> 505</td><td> 280</td><td> 383</td><td></td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td><td> -</td>

<td> Bitumen</td><td> 55.0</td><td> 0.0</td><td> 0.0</td><td> 30.0</td><td> 0.0</td><td> 0.0</td><td> -</td>

<td> Water</td><td> 25.5</td><td> 100.0</td><td> 100.0</td><td> 58.0</td><td> 100.0</td><td> 100.0</td><td> -</td>

<td> Solids</td><td> 19.5</td><td> 0.0</td><td> 0.0</td><td> 12.0</td><td> 0.0</td><td> 0.0</td><td> -</td>

<td> Heat capacity</td><td> 0.480</td><td> 0.997</td><td> 0.245</td><td> .0704</td><td> 1.003</td><td> 0.997</td><td> -</td>

<td> Specific gravity</td><td> 1.19</td><td> 1.00</td><td> 0.88</td><td> 1.11</td><td> 0.96</td><td> 1.00</td><td> -</td>

<td> Total Volume</td><td> 1429</td><td> 1538</td><td> 407</td><td> 1822</td><td> 1157</td><td> 1538</td><td> -</td>

<td> Temp</td><td> 78</td><td> 90</td><td> 140</td><td> 78</td><td> 195</td><td> 90</td><td> -</td>

<td> Stream No.</td><td> 22</td><td> 23</td><td> 24</td><td> 26</td><td> 27</td><td> 28</td><td> 30</td><td> 31</td>

<td> Bitumen</td><td> 2</td><td> 238</td><td> 3</td><td> 0.00</td><td> 0.00</td><td> 0</td><td> 3</td><td> 3</td>

<td> Water</td><td> 1138</td><td> 1853</td><td> 1744</td><td> 0.00</td><td> 0.00</td><td> 1</td><td> 1744</td><td> 2023</td>

<td> Solids</td><td> 117</td><td> 291</td><td> 207</td><td> 0.00</td><td> 0.00</td><td> 0</td><td> 207</td><td> 207</td>

<td> Total</td><td> 1256</td><td> 2382</td><td> 1954</td><td> 0</td><td> 0</td><td> 10</td><td> 1954</td><td> 2234</td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td> Bitumen</td><td> 0.4</td><td> 10.0</td><td> .02</td><td> 0.0</td><td></td><td> 0.0</td><td> 0.2</td><td> .01</td>

<td> Water</td><td> 84.4</td><td> 77.8</td><td> 89.2</td><td> 100.0</td><td></td><td> 100.0</td><td> 89.2</td><td> 90.6</td>

<td> Solids</td><td> 15.2</td><td> 12.2</td><td> 10.5</td><td> 0.0</td><td></td><td> 0.0</td><td> 10.5</td><td> 10.5</td>

<td> Heat capacity</td><td> 0.924</td><td> 0.835</td><td> 0.914</td><td> 0.245</td><td> 1</td><td></td><td> 0.914</td><td> 0.924</td>

<td> Specific gravity</td><td> 1.06</td><td> 1.09</td><td> 1.07</td><td> 0.96</td><td> 0.96</td><td> 0.96</td><td> 1.07</td><td> 1.06</td>

<td> Total Volume</td><td> 4746</td><td> 8724</td><td> 7294</td><td> 373</td><td></td><td></td><td> 7294</td><td> 8440</td>

<td> Temp</td><td> 94</td><td> 78</td><td> 78</td><td> 90</td><td> 165</td><td> 160</td><td> 78</td><td> 94</td>

As can be appreciated, the process allows a very efficient recovery of bitumen from tar sand.

As can also be appreciated, the use of a mobile facility that is capable of mining oil bearing materials, processing them, and depositing the resulting tailings in the mined out area in the immediate vicinity, dramatically reduces the material

CA 02332207 2001-10-02 handling undertaking. The advantages of this mobile facility and the corresponding process over conventional recovery technologies are major. These advantages include:

• much higher energy efficiency and consequent lower carbon dioxide generation;

• much smaller disturbed land footprint;

• no tailings ponds with their attendant need for eventual remediation;

• possible land reclamation and reforestation on a short term;

• no ore sterilization by tailings ponds because there are none;

• reduced air pollution from equipment because much less equipment is required;

• reduced draw of fresh water resources due to the recycling of process water when used as a solvent;

• reduced consumption of granular resources;

• increased thermal efficiency due to the recycle of process solvent;

• increased value of the oil shale and tar sand reserve because of overall cost efficiency; and • much reduced possibility of environmental impact that could trigger significant concerns to the public.

Although a preferred and other possible embodiments of the invention have been described in detail herein and illustrated in the accompanying figures, it is to be understood that the invention is not limited to these embodiments since various changes and modifications may be effected therein without departing from the scope or spirit of the present invention.