Chemical rejuvenation process to permanently increase the API gravity of crude oil and bitumen

Abstract

The invention relates to a method of increasing the American Petroleum Institute (API) gravity of feedstocks by reacting one or more mono-cyclic ether solvents such as oxolane with the asphaltene resident in bitumen or crude oils, at an ambient or elevated temperature, and at ambient or elevated pressure, to increase the API gravity and the economic value of the bitumen or crude oil, and a method for in situ manufacturing a mono-cyclic ether, oxolane, to rejuvenate bitumen or heavy crude oils into their younger lighter crude oils by blending methyl linoleate and methanol in a ratio; heating to produce oxolane; and contacting the oxolane as a solvent with the asphaltene resident in bitumen and heavy crude oils to release not only aromatic compounds, represented by toluene, but also the paraffinic alkanes, represented by n-heptane, making the feedstocks ready for extraction, separation of sand, pipeline transport and refining.

Claims

1. A method of permanent increase in the American Petroleum Institute Gravity of crude oil and bitumen, that the increase in the American Petroleum Institute Gravity is a permanent change such that remains after the crude oil or bitumen cools, wherein the blending of in situ produced reaction products with crude oil or bitumen occurs either above ground, at an inlet to an pump that moves the crude oil or bitumen into a storage tank, or below ground, at a reservoir or oil bearing stratum before the crude oil or bitumen enters a well casing for transport to ground level, wherein in situ manufacturing a mono-cyclic ether compound occurs to rejuvenate bitumen or heavy crude oil into heavy and intermediate crude where the method comprises: a) esterification of a carboxylic group on a fatty acid, present in a vegetable oil, reacts with an alcohol, in the presence of an acid or metallic catalyst, to produce an ester; b) reaction, where the ester reacts with an alcohol, in the presence of heat, to produce a mono-cyclic ether; and c) location of the occurrence of the reaction, as either above ground, at the inlet to the pump that moves the bitumen or heavy crude into a storage tank or below ground, at an inlet to a steam generator and the reaction products are subsequently contacted with the bitumen or heavy crude content of the reservoir or oil bearing stratum.

2. The method according to claim 1, wherein a mono-cyclic ether compound is oxolane produced from esterification of the fatty acid linoleate, the alcohol is methanol, and the catalyst used in the esterification reaction is hydrochloric acid or divalent zinc metal.

3. The method according to claim 1, wherein the vegetable oil is made from soy or corn or other vegetable oils, that contain a minimum of fifty percent linoleic fatty acid, and the linoleic fatty acid content of the vegetable oil is increased by cooling, followed by separation of the condensed fatty acid, in one or more of the following stages that occur at a temperature of: a) below the melting point for palmitic fatty acid; b) below the melting point for oleic fatty acid.

4. The method according to claim 1, wherein when the reaction occurs above ground, a mono-cyclic ester compound is methyl linoleate that is present in a minimum weight ratio of one and six tenths by weight to methanol present at one by weight, the heat is at a minimum temperature of sixty degrees centigrade and the pressure is at one bar, and the reaction products are subsequently contacted with the bitumen or heavy crude at the inlet to the pump, that moves the bitumen or heavy crude into a storage tank.

5. The method according to claim 1, wherein when the reaction occurs below ground, the mono-cyclic ester compound is methyl linoleate, present in a minimum weight ratio of one and six tenths by weight to methanol present at one by weight, the heat is at minimum of three hundred degrees centigrade and a maximum of four hundred degrees centigrade, and the reaction products are subsequently contacted with the bitumen or heavy crude, located in the reservoir or oil-bearing stratum, achieves the status of a superfluid at the pressure in excess of three hundred bars.

6. A method for in situ manufacturing a mono-cyclic ether compound, oxolane, to rejuvenate bitumen or heavy crude oils into their heavy and intermediate crude oils so that the increase in the American Petroleum Institute Gravity is a permanent change after the bitumen or heavy crude oil cools, the method comprising: using a vegetable oil made from soy, corn or other food crops, as a source material containing a minimum of 50% linoleic fatty acids; reacting the linoleic fatty acid with methanol, in the presence of an acid or metallic catalyst, to convert to methyl linoleate; blending linoleate and methanol in a selected weight, using a ratio of 1.6:1, and heating to produce oxolane; and contacting the oxolane as a solvent, with an asphaltene that resides in an above ground tank by injecting the oxolane into a feed pump, or with the asphaltene that resides in a underground deposit by injecting oxolane into the steam generator.

7. The method for manufacturing oxolane according to claim 6, where the concentration of linoleic fatty acid content is increased in one stage of cooling to a minimum of 60% by substantially removing the saturated fatty acid content, composed mainly of palmitic fatty acid and stearic fatty acid from soy oil or another oil, and terminating the process at this point or subsequently employing a second stage of cooling, where the concentration of linoleic fatty acid content is increased to a minimum of 90% by substantially removing the linoleic fatty acid.

8. The method for manufacturing oxolane according to claim 6, wherein prior to injection upstream of the feed pump to above ground storage tanks that contain heavy crude or bitumen, the oxolane is produced by mixing methyl linoleate and methanol, at a volumetric ratio of 1.6 to 1, at a temperature of 60 C. and pressure of 1 bars (15 psi), and is tested to a Kauri-Butanol solvent value of up to 850, and wherein the produced oxolane increases the API gravity of the crude oil by contacting the reaction product with the asphaltene that resides in the tank.

9. The method for manufacturing oxolane according to claim 6, where the method is for the treatment of heavy crude or bitumen deposits with produced oxolane by injecting steam mixed with methyl linoleate and methanol, at a volumetric ratio of 1.6 to 1, that achieves superfluid status at a temperature of 300 to 400 C., and pressure of 300 bars (4,400 psi), to increase the API gravity of the deposit by contacting the reaction mixture with the deposits.

Description

DESCRIPTION OF THE DRAWINGS

(1) The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the office upon request and payment of the necessary fee.

(2) To further clarify the above and other advantages and features of the present invention, a more particular description of the invention will be rendered by references to specific embodiments thereof, which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be limiting of its scope.

(3) The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

(4) FIG. 1 shows the geographic location of Venezuela's heavy crude oil reserves. The government of Venezuela has partitioned the heavy oil belt into six areas and subdivided the areas into blocks which have become the project units. The plan is to start enhanced recovery methods after the cold production phase. Enhanced Oil Recovery primarily uses injected steam. New projects are required to include upgrading facilities, located near the coast. The unit supply cost for the Orinoco extra-heavy oil produced cold with multilateral wells is much lower than Canadian production costs of bitumen because favorable fluid and reservoir conditions result in sustained high production rates per well. Current estimates of the supply costs for the Orinoco extra-heavy crude oil are as little as one-third of Canadian Bitumen supply costs.

(5) FIG. 2 compares and contrasts the chemical composition, based on number of carbons in the compounds, of natural gas and crude oil and further identifies tars and its subset asphaltenes in the crude oil.

(6) FIG. 3 utilizes the graphs of crude oil's viscosity vs. temperature to compare the temporary benefits of viscosity reduction of enhanced oil recovery with conventional steam injection to the permanent viscosity reduction with oxolaned enhanced steam injection.

(7) FIG. 4 compares key parameters of crude oil classified as heavy and intermediate extracted from wells in the same Venezuelan geographical location, and a blend crude oil suitable for refining, produced by blending the heavy crude oil with a light crude oil.

(8) FIG. 5 illustrated is that asphaltene, found in crude oil and bitumen, can be operational defined as composed of the petrochemical soluble toluene and the petrochemical insoluble n-heptane.

(9) FIG. 6 illustrates the degree of dissolution of asphaltene by the solvent xylene as compared to the solvent oxolane.

(10) FIG. 7 is a simulation of the performance of the mono-cyclic ether solvents on the destruction of Merey heavy crude into Puerto La Cruz intermediate crude.

(11) FIG. 8 is a graphical representation of the relationship between the quantity of asphaltene required to be deconstructed from heavy crude oils to achieve an API of 30 Degrees and Example Two.

(12) FIG. 9 is a process diagram for preferred embodiments of the present invention where the oxolane solvent is produced in situ either down well and on the surface.

(13) FIG. 10 illustrates Lake Guanoco Venezuela Crude Oil with API gravity of 4 degree (top graph), and bird's eye view of asphaltene crude being treated (bottom graph).

DETAILED DESCRIPTION OF THE INVENTION

(14) Asphaltene deconstruction is achieved with oxolane (CH.sub.2).sub.4O, a moderately bipolar solvent, thus avoiding need to add detergent or micelles present in the sub 100 Kauri-butanol (K-b) value solvents used for down well applications, that first breaks through the shell of resin that incases the asphaltene by the polar portion of the molecule attaching and oxidizing the resin and then by the non-polar portion moving through the asphaltene, to release the aromatic fractions represented by toluene and then releases the paraffinic alkanes fraction represented by n-heptane.

(15) As shown in FIG. 4, to obtain an intermediate crude with API of 36.5, that is suitable for refining, the heavy crude with API of 14.7 is blended in a one to one volumetric ratio with light crude with API gravity of 58.8. Also shown is that the same Venezuelan geographic location produces both heavy crude oil and intermediate crude oil. The analyses of these two oils indicate that the heavy crude oil with API of 14.7 contains 8.68% asphaltene and the light crude oil with API of 24 contains 4.78% asphaltene. The heavy crude oil has been exposed to bacterial action for longer time than the light crude and during this time the asphaltene content has almost doubled. If the asphaltene content in the heavy crude oil can be deconstructed into lighter compounds, then the oil would experience rejuvenation and intermediate crude oil would be resulted in, avoiding the need for light crude oil blending to produce a similar result.

(16) Asphaltene is a carbonaceous material found in crude oil, bitumen, and coal. Asphaltene, with a C:H ratio of approximately 1:1.2 and a distribution of molecular masses in the range of 400 Daltons (33 carbons) to 1500 Daltons (125 Carbons), is extremely complex mixtures containing hundreds or even thousands of individual chemical compounds. As shown in FIG. 5, asphaltene is defined operationally as the n-heptane (C.sub.7H.sub.16), oil insoluble, and toluene (C.sub.6H.sub.5CH.sub.3), oil soluble.

(17) Production of Parrafinic Wells

(18) Solvents are classified as polar that dissolve in water and non-polar that dissolve in oil. The Kauri-butanol value, obtained by ASTM D1133-13 test, is used to rate the power of solvents and is shown in parenthesis for the following solvents. Wells are plagued with loss of production when progressive pressure decrease occurs with accumulation of asphaltene and other material deposits in down well. Chemical treatment with diesel, hydrochloric acid and petroleum distillate solvents, such as xylene (99), are used to restore these wells production. In addition to the petroleum derived above mentioned materials, natural solvents have been used to restore these wells production. Among the natural solvents used are methyl 9-dodecenoate (C.sub.13H.sub.24O.sub.2) (85), D-limonene (C.sub.10H.sub.16) (67), methyl laurate (C.sub.13H.sub.26O.sub.2) (77), and methyl soyate (59).

(19) In the present invention, one or more mono-cyclic ethers serving as a chemical super solvent, are in situ manufactured in underground deposits by enriching injection steam or by pump injection into above ground storage tanks to transform bitumen or heavy crude oil to crude oil with higher API gravity by deconstruction of asphaltene to free not only aromatic compounds but also parafinic alkanes, making the feedstocks ready for transport and refining. The following table contains four mono-cyclic ethers (oxirane, oxetane, oxolane and oxane).

(20) TABLE-US-00005 Epoxides and Mono-Cyclic Ethers Mass Dielectric Dipole Boiling % Oxygen Common Name Formula Daltons Constant Moment Point, C By Weight Oxirane Ethylene Oxide C.sub.2H.sub.4O 44.05 13.9 1.89 10.7 36 Oxetane Trimethylene Oxide C.sub.3H.sub.6O 58.08 1.93 50 28 Oxolane Tetrahydrofuran (THF) C.sub.4H.sub.8O 72.1 7.58 66 22 Oxane Tetrahydropyran (THP) C.sub.5H.sub.10O 86.1 9 88 19

(21) In the present invention, oxolane (CH.sub.2).sub.4O, a mono-cyclic ether with a Kauri-butanol (K-b) value of 850, exceeds the power of previously used solvents for down hole applications by a sufficient multiplier to be used in the present invention to free not only aromatic compounds from the asphaltene, represented by toluene, but also the parafinic alkanes, represented by n-heptane as shown in FIG. 6. Wherein toluene, with K-b value of less than 100, is effective on the toluene in asphaltene to dissolve an estimated 35% by weight, and oxolane, with K-b value of 850, is effective on both the heptane and the toluene in asphaltene to dissolve an estimated 95% by weight.

(22) FIG. 7 shows a simulation of the performance of the mono-cyclic ether solvents such as oxirane, oxetane, oxolane and oxane on the destruction of Merey heavy crude into Puerto La Cruz intermediate crude, where the Merey heavy crude oil, that has an API gravity of 14.7 b, has contacted with a mono-cyclic ether solvent, resulting formation of Puerto La Cruz crude oil with an API gravity of 24.

(23) Polar solvents, such as methanol with a dielectric constant of 32.7, have large dipole moments: these solvents have bonds between atoms with very different electro negativities such as oxygen and hydrogen. Non-polar solvents, such as heptane with a dielectric constant of 1.92, have small dipole moments: these solvents contain bonds between atoms with similar electronegativity, such as carbon and hydrogen. Oxolane, 72.1 Da, that is representative of the small molecular family of epoxides, with a dielectric constant of 7.58, has a moderate dipole moment with a polar portion of the molecule useful as a solvent for the resin that surround the asphaltene, and the non-polar portion of the molecule useful as a solvent for the asphaltene. Oxirane which is the smallest of the family of mono-cyclic ether with a molecular weight of 44 Da, has a larger dielectric constant of 13.9 than that of oxolane and is therefore a better solvent. The carbons that occupy four of the five ring positions in the oxolane, and the carbon in the oxirane that occupies two out of the three ring positions are in addition to being non-polar are also aprotic, weakly reactive, for only hydrogen is bonded to the carbon. However, the oxygen that occupies one position in the oxolane ring, and one position in the oxirane ring, in addition to being polar is also aprotic, strongly reactive, for hydrogen is bonded to the oxygen. The latter portion of the oxirane and the oxolane that contains oxygen, strongly reactive, is the solvent that removes the polar resins from the asphaltene allowing the non-polar portion of the oxirane and the oxolane to act as a solvent on the asphaltene to liberate the toluene and hexane to reduce the specific gravity and to increase the API gravity.

(24) Quantity of Asphaltene Deconstruction to Achieve API 30 Degrees

(25) The Petrochemical Infrastructure, pipelines and refineries, is designed to accommodate crude oil with a minimum of API 30 based on the historically available light crude oil like West Texas Intermediate (WTI) crude with an API of 40. The present invention is capable of processing heavy crude oils to increase the API Degree sufficiently to obtain pipeline and refinery ready lighter crude oil with an objective of API 30 Degrees. The following table is prepared based on the physical characteristics of Puerto La Cruz and Merey heavy crude shown in FIG. 4.

(26) TABLE-US-00006 Removal to 30 Asphaltene API Degrees API SG Percent, % Lb./Gal. Lb./Gal. 8 1.0140 15.95 1.35 1.07 10 1.0000 12.76 1.06 0.78 15 0.9659 8.86 0.71 0.43 20 0.9340 5.98 0.47 0.19 25 0.9042 4.59 0.35 0.07 30 0.8762 3.82 0.28 0.00 35 0.8498 3.28 0.23 65 0.7206 0 0.00

(27) A graphic presentation of a subset of the above data is shown in FIG. 8. The table shows that the API Degree of a crude oil that has no asphaltene is estimated to be the light crude oil with an estimated value of 65. Based on data presented, to produce an intermediate crude oil with an API degree of 30, an intermediate crude oil with API degree of 25 required twenty nine percent (29%) of dosage of the epoxide solvent that is required for a heavy crude oil with API degree of 8.

(28) Pipeline Transportation

(29) Naphtha, a distillate with API gravity 65 degrees, is blended at a 10% volumetric dosage with Venezuelan crudes, API range of 8 to 60, to allow for pipeline transport. However, because of the inherent insolubility of asphaltene in naphtha there is delayed precipitation of asphaltene and because of the corrosive nature of naphtha the pipeline is subject to corrosion. Additionally, naphtha is a high value product that would be better tasked as an ingredient in jet fuel rather than adding it to crude to enable pipeline transport. The API of the blend of Venezuelan crude is calculated to be 26 by working back from the 10% dose of naphtha and an API gravity of 30 degrees required to allow pipeline (100*(30)=90*X+10*(65)).

(30) The above table shows that the API degree of a crude oil that has no asphaltene is estimated to be the light crude oil with an estimated value of 65 degrees: the API of naphtha. Based on data presented, to produce an intermediate crude oil with an API gravity of 30 degrees for pipeline transport, an intermediate crude oil with API degree of 25 required twenty nine percent (29%) of dosage of the oxolane, a mono-cyclic ether, that is required for a heavy crude oil with API gravity of 8 degrees. There is an equivalency between the dose of and the quantity of asphaltene that is to be destructed be pipeline ready crude at an API Gravity of 30 degrees. Therefore, only 28% of the asphaltene content in crude with API Gravity of 8 degrees is present in a crude with API Gravity of 25 degrees. The estimated cost of treatment with oxolane, a mono-cyclic ether, at 1 part to 725 parts of crude oil, based on a cost of $75 a gallon, is $5.80 a barrel.

(31) As stated above, the current practice in Venezuela is to allow pipeline transport of Merey-16, API gravity of 16 degrees, is by blending heavy naphtha at a dose of 10% by volume at a cost of $1.50 per gallon ($6.30 per barrel) and deal with the nagging problem of Delayed Asphaltene Precipitation (DAP). DAP is avoided when the Merey-16 crude is treated with the mono-cyclic Ether, oxolane, at one part to 725 parts of crude to allow pipeline transport at a cost of $75.00 per gallon ($5.80 per barrel). Also in Venezuela, required is approximately one third (), by volume, of heavy naphtha, API gravity of 55 degrees, for blending with Merey-16, API Gravity of 16 degrees, to produce refinery ready crude. Heavy naphtha at a dose of 33% by volume at a cost of $1.50 per gallon ($21.00 per barrel) and deal with the nagging problem of delayed asphaltene precipitation (DAP).

(32) Process Diagram

(33) Two of the many embodiments of the present invention are shown in FIG. 9. Numerous other embodiments are possible to practice the present invention. All embodiments of the present invention start with linoleic fatty acid (18:2) obtained from vegetable oils. Typical compositions of some vegetable oils are contained in the following table on a weight percent basis.

(34) TABLE-US-00007 Soy Corn Canola Palm Voila Saturated 12:0 - Lauric 0.25 14:0 - Myristic 0.12 16:0 - Palmitic 10 80 42.5 2 18:0 - Stearic 4 14 4.6 13.6 20:0 - Arachidic 3 0.25 Other 1 0.19 0.85 Unsaturated 16:1 - Palmitoleic 0.2 18:1 - Oleic 23 63 40.8 26.8 18:2 - Linoleic 51 2.9 21 10.6 54.6 18:3 - Linolenic 10 0.1 9 0.3 1.3 Other 1 0.19 0.85 Subtotal 85 3 93 52.09 83.55 Saturated Subtotal 15 97 7 47.91 16.45 Unsaturated Subtotal 85 3 93 52.09 83.55 Total 100 100 100 100 100

(35) The Source material for the present invention is linoleic fatty acid (18:2) from vegetable oil. As shown in the above table linoleic fatty acid is only found at greater than 50% concentration by volume in two oils, soybean oil and Voila oil. These two oils are available in sufficient quantities to be considered for use in processing the world's enormous volumes of bitumen and heavy crude oil. Voila oil, is a byproduct of the manufacture of corn ethanol that is mandated to be 10% of the U.S. gasoline fuel supply. It is almost ironic that the petroleum industry, that regularly lobbies to reduce the corn ethanol content in gasoline, may come to embrace the Voila as a weapon to solve its nagging problem of reducing the viscosity and increasing the API gravity of bitumen and heavy crude oils so that they can be refined.

(36) Dual Cooling

(37) In the present invention it is desirable to increase the concentration of linoleic fatty acid (18:2) in the source material soy oil or Voila as a precursor to obtain a high yield of oxolane in the thermally activated reaction of the linoleic fatty acid (18:2) with methanol.

(38) TABLE-US-00008 Weight, % Weight, % Component VOILA Soy Melting Point, C. Saturated Palmitic 2 10 63 Stearic 13.5 4 70 Other 1 1 Total 16.5 15 Unsaturated Oleic 27 23 13.4 Linoleic 55 51 5 Linolenic 1 10 10 Other 0.5 1 Total 83.5 85 Grand Total 100 100

(39) The higher melting point of both saturated fatty acids than unsaturated fatty acids and higher melting point of oleic fatty acid (18:1) than that of linoleic fatty acid (18:2), can be employed in a two-stage cooling process to increase the linoleic fatty acid (18:2) content in the soy or Voila oil source material.

(40) TABLE-US-00009 Cold Treatment VOILA Percent by Weight One - 25 C. Two - 0 C. Saturated 16.5 0 0 Unsaturated 27 32 0 Linolenic 56.5 68 100 Other Total 83.5 100 100 Grand Total 100 100 100 Percent by Weight Cold Treatment Soy Oil One - 25 C. Two - 0 C. Saturated 15 0 0 Unsaturated 23 27 0 Linolenic 61 72 98 Other 1 1 2 Total 85 100 100 Grand Total 100 100 100

(41) First, the oil is cooled to a temperature below the melting point of palmitic fatty acid (16:0), 63 C., and above the melting point oleic fatty acid, 13.4 C. In one embodiment of the present invention, the first stage cooling temperature is 25 C. At this temperature, if 100% of the saturated fatty acids were removed from the oil, the linoleic/linolenic fatty acids (18:2/18:3) content would increase to 72% for soy oil and 68% for VOILA. Second, the oil is further cooled to a temperature below the melting point of oleic fatty acid (18:1), 13.4 C., and above the melting point of linoleic fatty acid (18:2), 5 C. In one embodiment of the present invention the second stage cooling temperature is 0 C. At this temperature, if 100% of the oleic fatty acids were removed from the oil, the linoleic/linolenic fatty acids (18:2/18:3) would increase to 98% for both soy oil and for VOILA. VOILA is preferred to soy oil as a source material because before cooling process, the ratio of linoleic/linolenic fatty acids (18:2/18:3) is 55:1 versus 5.1:1 making more linoleic fatty acids available to produce oxolane.

(42) Soy based saturated fatty acids are a feedstock used to meet the twenty five percent (25%) minimum bio content requirement for biodegradable motor oil that has been mandated for use in U. S. Government vehicles. The first stage cooling produces saturated fatty acids that after conversion to esters and removal of glycerine, are suitable for this biodegradable motor oil. If VOILA is the source material, rather than soy, the bio based for motor oil contains seven times the content of stearic fatty acid (18:0) as compared to the palmitic fatty acid (16:0) content, rather than soy with 0.4 times the content of stearic fatty acid as compared to the palmitic fatty acid (16:0) content. Stearic fatty acids rich feedstocks are preferred to palmitic fatty acids rich feedstocks for biodegradable motor oil because steric fatty acid is more like the petroleum base mineral stocks that are blended with to produce the motor oil. First, stearic fatty acid has an 18-carbon chain length which is the mean length of the 16 to 18 carbon chain length of the petroleum base mineral stock. Second, the specific gravity of stearic fatty acid of 0.94 is in range of that of the petroleum based mineral stock rather than the incompatible specific gravity of palmitic fatty acid of 1.61.

(43) The oleic fatty acid produced in the second stage cooling process will be processed to technical grade purity of 90% to find use in oil and gas exploration and production.

(44) Esterification

(45) The production of the ester methyl linoleate (C.sub.19H.sub.34O.sub.2) from the fatty acid linolenic (18:2) is shown in FIG. 9, wherein the carboxylic group on the fatty acid reacts with an alcohol, typically methanol (CH.sub.3OH), in the presence of an acid catalyst, typically hydrochloric acid, to produce the ester. The use of an acid catalyst is selected, rather than a basic catalyst, is to preserve the unsaturated bonds in the linolenic fatty acids that are vital to the production of oxolane in the subsequent reaction. The use of acid catalyst is not only more costly than basic catalysts but the reaction progresses more slowly. The process of acid esterification is Fischer esterification. Zinc (II) as a solid catalyst has been used in various compounds to reduce reaction time and may have application in embodiments of the present invention.

(46) Reaction

(47) The reaction to produce oxolane is shown as follows using two parts, methyl linoleate as part A and methanol is part B, when the requisite amount of heat is applied, the reaction proceeds to form oxolane.

(48) ##STR00003##

(49) The reactant methyl linoleate is 71.7% by weight and 61.6% by volume of the total reactants. The product oxolane is 90.7% by weight of the total products of the reaction.

(50) In Situ Production

(51) The point at which the above reaction occurs is the point at which heat is added to the mixture containing 1.6 parts by weight of methyl linoleate to 1 part by weight of methanol. This mixture can be transported as part A and part B and then added in the above referenced proportions at the site for production of the oxolane (see FIG. 9).

(52) The reaction occurs above ground at the inlet to the pump that moves the bitumen of heavy crude, after heating, into a storage tank. The temperature in this embodiment is 60 C. (140 F.). At this temperature the reaction proceeds as liquid because the 60 C. (140 F.) temperature is below the boiling point of the reactant methanol, 64.7 C. (148.5 F.), and the product oxolane, 66 C. (150.8 F.). The pressure in the pump, where the reaction occurs is 1 bar (14.7 psi).

(53) The reaction occurs below ground at the inlet to the steam generator used for enhanced oil recovery of bitumen or heavy crude. The temperature in this embodiment is 300 C. to 400 C. The pressure underground at the point that the oxolane contacts the deposits is approximately 300 bar (4,400 psi).

(54) These temperatures and pressure conditions transform solvents, oxolane and carbon dioxide, into supercritical fluids because these conditions are above the critical point for these materials. This allows the solvents to effuse through the solids, deposits of bitumen or heavy crude like a gas and to dissolve materials in the asphaltene/tar like a liquid. The extraction of the aromatic and alkane materials occurs at an accelerated rate due to the low viscosity and high diffusivity associated with supercritical fluids. A secondary effect is that particles of asphaltene are reduced in size by the supercritical fluids to the nanoscale so that there is no possibility of precipitation of asphaltene, a condition that commonly occurs when heavy crude oil is blended with light crude oil or distillates, after oxolaned enriched steam.

Experiment OneNatural Solvent Methyl 9-Dodecenoate

(55) Methyl 9-dodecenoate (C.sub.13H.sub.24O.sub.2) is a natural solvent with a Kauri-butanol value of 85. A commercially available product containing this solvent at 50% by volume was used to treat Venezuelan heavy crude oil for Block C North and it was determined that a 10% by weight of this product was required to produce a crude oil that was suitable for transportation. The Kauri-butanol value for the mono-cyclic ether solvent oxolane of 850 is ten times that of the natural solvent. The dose and Kauri-butanol value of the natural solvent is used to forecast the dose of the oxolane required to be treat the Venezuelan heavy crude oil with 1 part of the oxolane solvent to 200 parts of crude is equivalent to 27 ounces oxolane solvent per barrel of crude.

(56) At a cost of the mono-cyclic ether solvent oxolane of one hundred dollars ($75) per gallon the cost of treatment of the Venezuelan heavy crude oil, with API Gravity of 8 degrees is $21 a barrel. Shown in FIG. 8 is that the asphaltene content, that is to be removed to achieve an API Gravity of 30 degrees, for crude with API gravity of 8 degrees is 1.07 pounds per gallon and the asphaltene content, that is to be removed to achieve an API Gravity of 30 degrees, of crude with API gravity of 25 degrees is 0.07 pounds per gallon. There is an equivalency between the dose of the mono-cyclic ether solvent oxolane and the quantity of asphaltene that is to be destructed to produce refinery ready crude at an API gravity of 30 degrees. Therefore, only 28% of the asphaltene present in crude with API gravity of 8 degrees is present in a crude with API of 25 Degrees. So, at a cost of the solvent oxolane was seventy five dollars ($75) per gallon, the cost of treatment of the Venezuelan heavy crude oil with API of gravity of 25 degrees is $5.88 a barrel.

Experiment TwoMono-Cyclic Ether Solvent Oxolane

(57) As previously mentioned, the specific gravity of a crude oil with API gravity of 8 degrees, such as the Venezuelan heavy crude oil for Block C North, @ 60 F., is 1.0140. The crude sample is placed by spoon into two vials containing 1.35 ounces (40.5 gm) that are labeled 1, and 2. Sample 2 is the reference sample to be untreated. The samples are placed into a crock pot fill with water and the temperature is measured and the electrical heater control is adjusted to bring and maintain the water bath to 82 C. (180 F.). This is the temperature to which Venezuelan heavy crude oil is heated to allow transport. A crude oil with API of 8 degrees with a viscosity of 5,000 cP measured at the standard temperature of 100 F., thins to achieves a viscosity of 400 cP when heated to 82 C. (180 F.). A dose of 1.0 milliliters of reagent grade of the mono-cyclic ether solvent, oxolane, is added to Sample 1 at, weight/weight, of solvent to crude of 1:45. The API gravity of the sample before/after treatment is measured to determine API gravity conforming to ASTM D-1250 and reported below.

(58) TABLE-US-00010 Sample Dose API 1 1/45 13.0 2 None 8.0

(59) Venezuela exports two grades of crude oils. One is refinery ready crude oil with API gravity of 30 degrees and the other is Merey-16 heavy crude with a typical API gravity of 16.3 degrees. The above tests results are extrapolated to estimate the performance of the mono-cyclic ether solvent, oxolane to convert Merey-16 heavy crude into refinery ready crude oil with API gravity of 30 degrees. These results are shown in FIG. 8 where in the change in API gravity from 8.0 to 13.0 degrees results from a decrease in the asphaltene content of 6.13% is used to predict that a 4.33% reduction in asphaltene content of the Merey-16 heavy crude with API of 16.3 degrees can be upgraded to refinery ready crude oil with API gravity of 30 degrees from a decrease in asphaltene content of 4.33%.

Experiment ThreeLake Guanoco Crude's Deconstruction of Asphaltene

(60) Lake Guanoco is one of the world's five natural tar lakes. It has an API gravity of 4 degrees. The crude is shown in the upper photo of FIG. 10. The crude undergoing treatment is shown in the bottom photo of the figure. Note the two rings formed around the central glob of Guanco crude oil. This is a visual of the process of deconstruction of the crude with the reaction progressing as the blob is undergoing decomposition by the relatively clear liquid that contains two milliliters of the mono-cyclic ether solvent (oxolane). The crude is transformed into the lighter crude, in the outer ring, as heavier crude, in the central ring, is deconstructed by the relatively clear liquid contained in the intermediate ring. The small volume of the oxolane dose is augmented by the volume of the n-heptane and toluene: these are the fractional building blocks of the asphaltene that are liberated when the oxolane oxidizes the resin compounds that form a shell surrounding the asphaltene and liberate the n-heptane and the toluene. The outer ring contains the new general population of compounds, the lighter crude oil, that tests to a higher API gravity than the heavy crude oil in the inner ring and this new crude has the added benefit on improved pipeline transport as a direct result of the spontaneous blending of the crude with the internally generated n-heptane and toluene.

Experiment FourLake Guanoco Crude's Visual Proof

(61) A dollop of the Lake Guanco natural tar, with API gravity of 4 degrees, was placed in a drinking glass containing water, at a temperature of 100 F., the dollop was observed to sink to the bottom of the glass. The dollop sank because the API gravity was less than an API gravity of 10, that is the point on the API gravity scale where materials with this value are neutral buoyant.

(62) One hundred grams of the Lake Guanco natural tar was first heated to 150 F. and then blended, over two minutes, as twelve millimeters of oxolane was added. After the treated tar cooled to 100 F., a quantity of the treated tar was spooned into a second drinking glass containing water, at a temperature of 100 F. The tar was observed to float on top of the water because the API gravity was greater than an API gravity of 10, that is the point on the API gravity scale where materials with this value are buoyant.

(63) This relatively simple experiment demonstrates that blending the tar with oxolane increase the API gravity of the tar.

(64) Ultra Sound and Sulfur Removal

(65) In a preferred embodiment of the present invention, ultrasound is used to reduce the requisite dose of the mono-cyclic ether solvent to increase the API of the crude oil being reacted with the solvent. When augmented by ultrasound the solvent's oxidation of the resin shell that surrounds the asphaltene occurs in combination with the oxidation of the sulfur content of the crude oil. The sulfur is present in the crude as mercaptans, sulfides, disulfides and thiophenes. The conditions for operation of the ultrasound are frequency in the range of 20 to 50 KHz and power in the range of 5 to 100 watts per square centimeter.