METHOD AND PRODUCT FOR PARAFFIN AND ASPHALTENES INHIBITING

Abstract

Disclosed is method of and product for enhanced oil recovery for a crude oil production well. The method includes the steps of pyrolyzing rubber materials including the steps of heating the rubber materials to form pyro-vapors, condensing the pyro-vapors to form pyro-gas and pyro-oil where the pyro-oil includes an inhibitor solution including non-polar hydrocarbons and polar hydrocarbons. The inhibitor solution is injected as an injection stream into the crude oil production well to facilitate production of crude oil from the crude oil production well.

Claims

1. A method of enhanced oil recovery of crude oil from a production well comprising, pyrolyzing rubber materials including the steps of heating the rubber materials to form pyro-vapors, condensing the pyro-vapors to form pyro-gas and pyro-oil where the pyro-oil includes an inhibitor solution including non-polar hydrocarbons and polar hydrocarbons, mixing the inhibitor solution with crude oil to form an injection stream and injecting the injection stream into the production well to facilitate production of the crude oil from the production well.

2. The method of claim 1 wherein the inhibitor solution is about 0.15% or more of the injection stream to lower the Cloud Point temperature of paraffin in the crude oil of the production well.

3. The method of claim 2 where the properties of the inhibitor solution are approximately Specific Gravity (60 F.): 0.82, Weight (60 F.): 6.8 lbs/US gal, Flash Point (SFCC): 74 F., Pour Point (ASTM D-97): <40 F., Viscosity (ASTM D-455) (60 F.): 32, Solubility: Oil-soluble, Ionic Character: Anionic, pH: 7.5.

4. The method of claim 1 wherein the non-polar hydrocarbons are about 3% to 12% of the pyro-oil.

5. The method of claim 1 wherein the rubber material is scrap tires. (Original) The method of claim 1 wherein the non-polar hydrocarbons include Benzoic acid; 1-Piperidinecarboxaldehyde and Caprolactam.

6. The method of claim 1 wherein the polar hydrocarbons include Acetic acid; Phenol; Aniline; Diphenyl sulfone; Benzoic acid, methyl ester; Propanoic acid, 2-methyl-; Butanoic acid; Pyridine; Decane; 1,2-Benzisothiazole.

7. The method of claim 1 where the pyrolyzing step heats over an INCREASE period to cause the temperature to rise up to Tmax, causes the temperature to be maintained at about Tmax during a STEADY period and allows the temperature to cool during a DECEASE period where Tmax is between approximately 800 C. and 1100 C. and where the INCREASE period, the STEADY period and the DECEASE period together occur over approximately 3 to 5 hours.

8. A method of enhanced oil recovery of crude oil from a production well where the well has production impeded by paraffin comprising, pyrolyzing scrap tires including the steps of heating the scrap tires to greater than 800 C. to form pyro-vapors, condensing the pyro-vapors to form pyro-gas and pyro-oil where the pyro-oil includes an inhibitor solution formed of non-polar hydrocarbons and polar hydrocarbons wherein the non-polar hydrocarbons constitute at least 3% of the pyro-oil, mixing the inhibitor solution with crude oil to form an injection stream and injecting the injection stream into the production well to solubilize the paraffin to increase production of the crude oil from the production well.

9. The method of claim 8 wherein the pyrolyzing is carried out until the non-polar hydrocarbons constitute 3% to 12% of the pyro-oil.

10. The method of claim 8 wherein the scrap tires are whole tires.

11. The method of claim 8 wherein the injection stream includes a first injection with a first injection quantity for establishing an increased flow of the crude oil and includes maintenance injections with maintenance injection quantities substantially less than the first injection quantity.

12. The method of claim 8 wherein the production well includes piping systems and a below ground pump receiving the injection stream.

13. The method of claim 8 wherein the injection stream is applied to the production well at elevated temperatures.

14. The method of claim 8 wherein the injection stream is applied to the production well at elevated pressures.

15. The method of claim 8 wherein the injection stream is applied to the production well in maintenance quantities on multiple applications at maintenance intervals over a period of time.

16. The method of claim 8 wherein the injection stream is applied to storage tanks.

17. The method of claim 8 wherein the injection stream propagates into an oil reservoir.

18. The method of claims 8 wherein the production well includes a pumping and distribution unit having pumps, piping systems and storage units receiving the injection stream.

19. A method of enhanced oil recovery of crude oil from a crude oil production well having an injector, piping, a core including an annulus, a pump and lift tubing where the core extends into a well bore to a crude oil reservoir for pumping crude oil having a viscosity increased by paraffin components comprising, pyrolyzing scrap tires including the steps of heating the scrap tires up to a Tmax temperature greater than 800 C. where the heating occurs over a period from 3 hours to 5 hours to form pyro-vapors, condensing the pyro-vapors to form pyro-gas and pyro-oil where the pyro-oil includes an inhibitor solution formed of non-polar hydrocarbons and polar hydrocarbons, mixing the inhibitor solution with the crude oil of the production well in a percentage greater than 0.15% to form an injection stream for lowering the Cloud Point temperature of paraffin in the crude oil of the production well, injecting the injection stream into a loop including the injector, the piping, the annulus, the pump and the lift tubing, providing a continuous flushing of the injection stream in the loop for solubilizing the paraffin to decrease the viscosity of the crude oil.

20. The method of claim 19 wherein the injection stream propagates into the oil reservoir.

21. The method of claim 19 wherein the injection stream is applied to the production well at elevated temperatures.

22. The method of claim 19 wherein the injection stream is applied to the production well at elevated pressures.

23. An inhibitor solution formed of non-polar hydrocarbons and polar hydro-carbons where the non-polar hydrocarbons include Benzoic acid; 1-Piperidinecarboxaldehyde and Caprolactam.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 depicts a block diagram of a pyrolysis system producing an inhibitor.

[0028] FIG. 2 depicts a production well for pumping crude oil from the ground together with an inhibitor apparatus for injecting an inhibitor into the production well, pump systems, fluid piping and storage tank systems.

[0029] FIG. 3 depicts a chart showing the production rate of a well with hot-oil treatment and insertion of an inhibitor solution.

[0030] FIG. 4 depicts a chart showing the production rate of a well with hot-oil treatment and insertion of an inhibitor solution followed by maintenance quantities of the inhibitor solution.

[0031] FIG. 5 depicts the above-ground portion and the below-ground portion of a production well of FIG. 2 for pumping crude oil from the ground together with inhibitor apparatus for injecting an inhibitor into the above-ground portion and the below-ground portion of the production well.

[0032] FIG. 6 depicts further details of the pumping and distribution unit with connection to the below-ground pump.

[0033] FIG. 7 depicts a portion the pump in the up stroke position.

[0034] FIG. 8 depicts a portion the pump in the down stroke position.

[0035] FIG. 9 depicts further details of the pumping and distribution unit connected to the below-ground pump having a bend for horizontal extension.

[0036] FIG. 10 depicts further details of the pyrolysis system of FIG. 1.

DETAILED DESCRIPTION

[0037] In FIG. 1, a pyrolysis system 5 operates to produce an inhibitor 10. The inhibitor 10 includes non-polar components 14 and polar components 15. The pyrolysis system 5 pyrolyizes waste tires to form the inhibitor 10. Tire pyrolysis involves the thermal degradation of the tires in the absence of oxygen. Tire pyrolysis is used to convert tires into pyro-materials including pyrolysis gases (pyro-gases), pyrolysis oils (pyro-oils), and pyrolysis solids (pyro-chars) and steel.

[0038] In pyrolysis system 5, waste tires are loaded for pyrolysis processing and pyro-solids are unloaded after pyrolysis processing. The pyro-gases and pyro-oils are extracted during the pyrolysis processing.

[0039] The pyrolysis processing occurs as follows. Typically, the waste tires are bailed and loaded into a furnace during a LOAD period. After the tires are loaded, a furnace door is closed and the furnace chamber becomes a sealed retort. Next, nitrogen gas is injected into the furnace to purge the chamber and force oxygen out. A heat unit provides heat to the chamber and the temperature begins to rise during an INCREASE period. Initially, the temperature is at room temperature. Heating over the INCREASE period causes the temperature to rise up to Tmax. The temperature is maintained at about Tmax during the STEADY period. Thereafter the heat is turned off. A DECEASE period allows cooling to occur. The cooling can be accelerated by introducing cooling nitrogen into the furnace until the furnace approaches Tmin. The pyro-solids are unloaded during the UNLOAD period. Air is not introduced into the furnace while the temperature of any of the pyro-solids are over approximately 300 degrees F., otherwise the carbon can catch fire/oxidize when contact with oxygen is made.

[0040] The pyrolysis processing is effective to drive off the pyro-gases and pyro-oils. The pyro-gases and pyro-oils are extracted from the furnace during the INCREASE, STEADY and DECREASE periods.

[0041] The products of the pyrolysis process include carbon, liquid hydrocarbons (including inhibitor components), and other compounds gases and steel. The gases can be burned to generate electrical power. The inhibitor components are used in inhibitor solutions for inhibiting the adverse effects of paraffin and asphaltenes in production wells and petroleum processing and transporting equipment. The hydrocarbon products are created by condensing the pyro-vapor that is generated during the pyrolysis heating cycle (INCREASE, STEADY, DECREASE). The gas created in the sealed furnace is changed through differing applications of heat temperatures and durations to drive off more light or heavy ends of carbon string compounds, thus providing an ability to create variations of paraffin inhibitor strengths. The condensing system consists of multi-staged cooling chambers that produce, among other things, the hydrocarbon components. The condensing process breaks out three groups of carbon string compounds. First, the C1-C2 non-condensables gas at room temperature is produced. Next, the C3-C9 light condensables are produced. Following, the medium condensables C10 to C17 are produced. Finally, the heavies that include C18-C26 are produced. The heavies condense out first with the lights condensing at the end of the condensing process.

[0042] The dispersant product, inhibitor solution, selected from the condensing includes a blend of aromatic, aliphatic and naphthenic liquid organic hydrocarbons. The inhibitor solution is used for increasing crude oil production rates, decreasing lift costs and otherwise reducing the adverse effects of paraffin and asphaltenes in oil wells and related equipment. This inhibitor solution solubilizes paraffin and asphaltenes, lowers the cloud point in the oil bearing zone and reduces paraffin build-up in the oil bearing zone, in down-hole components and in other equipment. The inhibitor solution is added to hot oiling to increase the speed and efficiency of the hot oiling. Continued use of the inhibitor solution after hot oiling processing stabilizes production flow. The inhibitor solution is used for initial clearing and then on a continuous basis in a maintenance mode.

[0043] Typical properties of the inhibitor solution are Specific Gravity (60 F.): 0.82, Weight (60 F.): 6.8 lbs/US gal, Flash Point (SFCC): 74 F., Pour Point (ASTM D-97): <40 F., Viscosity (ASTM D-455) (60 F.): 32, Solubility: Oil-soluble, Ionic Character: Anionic, pH: 7.5.

[0044] It has been found that pyrolysis processing produces an inhibitor solution with non-polar components and polar components that are effective for paraffin and asphaltenes control.

[0045] The composition of the inhibitor solution is determined with laboratory gas chromatography-mass spectrometry (GC-MS) testing. The non-polar components in the inhibitor 10 are potent for paraffin control. Polar components in the inhibitor 10 are potent for asphaltenes control.

[0046] An inhibitor solution included 1.31% Polar, 5.30% Non-Polar, 2.58% Mostly Non-polar, 4.03% Both Polar and Non-Polar. The analysis is done using a Sample Size equal to 5,325,000 ng/ml as described in TABLE 1 and TABLE 2.

[0047] In general, to achieve a solution effective in controlling paraffin and asphaltenes, the solution is formed by a pyrolysis process including the steps of heating tires to a temperature of greater than 800 C. to form pyro-gas, condensing the pyro-gas to form pyro-oil where the pyro oil includes the solution with non-polar hydrocarbons that are a small percentage of the pyro-oil and with polar hydrocarbons that are a small percentage of the pyro-oil.

[0048] Pyrolysis processes in general for pyrolysis of tires are of a continuous nature or of a batch nature. The continuous pyrolysis processes for tires general operate at low temperatures of 300 C. or 400 C. The batch pyrolysis of tires is effective for temperatures from 800 C. to 1100 C. or higher. The higher temperatures of batch processing are important for controlling the formation of the particular polar and non-polar hydrocarbons that are effective as inhibitor components. Also, the higher temperatures of batch processing are import for removing pyro-oil from the carbon product. The higher the temperature and the longer the processing time, the greater the purity of the carbon product, that is, the lower the pyro-oil remaining in the carbon product. The greater the purity of the carbon product, the greater the commercial value of the carbon product. The more pure carbon product sells for a higher price and can be used in more industrial applications.

[0049] Using batch pyrolysis Tmax was about 1000 C. and the INCREASE, STEADY and DECREASE periods occurred over about 4 hours to produce the pyro-oil.

[0050] A Non-Polar analysis of the pyro-oil (including Non-Polar, Mostly Non-polar and Both categories) appears in the following Non-Polar TABLE 1.

TABLE-US-00001 TABLE 1 Compounds RT#1 Resp#1 Conc#1 % Polarity Benzoic acid 14.429 70652643 208139.9616 3.91 Non-polar.sup.B 1-Piperidinecarboxaldehyde 15.681 46039135 135629.5147 2.55 Non-polar Caprolactam 15.681 45890151 135190.6131 2.54 Non-polar.sup.M Benzoic acid, 4-methyl- 15.816 12668384 37320.5693 0.70 Non-polar 3,5-Dithiahexanol 5,5-dioxide 04.142 11874626 34982.1914 0.66 Non-polar 3,3-Bithiophene 22.133 4719804 13904.3601 0.26 Non-polar Benzoic acid, 4-cyano- 18.528 3966857 11686.2074 0.22 Non-polar Quinoline, 2-methyl- 16.378 2967618 8742.4888 0.16 Non-polar Benzonitrile 10.791 1698480 5003.6552 0.09 Non-polar Propinoic acid 04.737 1503912 4430.4664 0.08 Non-polar.sup.B Pentanoic acid 08.803 1526156 4495.9960 0.08 Non-polar Benzene, 2,4-diisocyanato-1-methyl- 16.990 1341867 3953.0876 0.07 Non-polar Benzoic acid, 4-cyano-, methyl ester 17.074 1231125 3626.8476 0.07 Non-polar Quinoline, 2,4-dimethyl- 18.332 1192934 3514.3368 0.07 Non-polar 2-Cyclopenten-1-one, 2,3-dimethyl- 11.588 850251 2504.8055 0.05 Non-polar 4-Ethylbenzoic acid 17.040 921629 2715.0836 0.05 Non-polar Phenol, 2-methyl- 12.093 705684 2078.9165 0.04 Non-polar.sup.B p-Cresol 12.447 745904 2197.4036 0.04 Non-polar Benzamide 16.748 705244 2077.6204 0.04 Non-polar.sup.M Cyclopentanone 06.545 565885 1667.0749 0.03 Non-polar 2-Piperidinone 14.665 482334 1420.9364 0.03 Non-polar 1,2-Benzenedicarbonitrile 15.625 560339 1650.7363 0.03 Non-polar Isopropyl phenyl ketone 18.006 455830 1342.8575 0.03 Non-polar Butylated Hydroxytoluene 19.202 492259 1450.1753 0.03 Non-polar Benzamide, N-methyl- 17.372 325493 958.8911 0.02 Non-polar Pyridine, 2,5-dimethyl- 09.813 113145 333.3202 0.01 Non-polar Acetophenone 12.335 190973 562.5988 0.01 Non-polar Benzonitrile, 4-ethenyl- 15.300 119235 351.2620 0.01 Non-polar Cyclohexasiloxane, dodecamethyl- 16.484 145295 428.0331 0.01 Non-polar 1-Hexen, 2(p-anisyl)-5-methyl- 17.220 157931 465.2575 0.01 Non-polar Cycloheptasiloxane, tetradecamethyl- 18.893 110013 324.0937 0.01 Non-polar Cyclooctasiloxane, hexadecamethyl- 21.033 160154 471.8064 0.01 Non-polar Diphenylacetylene 22.656 174116 512.9393 0.01 Non-polar Cyclononasiloxane, octadecamethyl- 22.886 92565 272.6920 0.01 Non-polar TOTAL 11.94 Non-polar.sup.B = Also Polar Non-polar.sup.M = Mostly Non-Polar

[0051] The Benzoic acid, 1-Piperidinecarboxaldehyde and Caprolactam components accounted for about 75% of the Non-Polar components. Over the temperature range from 800 C. to 1100 C., the Benzoic acid, 1-Piperidinecarboxaldehyde and Caprolactam components percentage may vary somewhat but still will be the preponderant portion of the Non-Polar components.

[0052] A Polar analysis appears in the following TABLE 2.

TABLE-US-00002 TABLE 2 Compounds RT#1 Resp#1 Conc#1 % Polarity Acetic acid 3.227 5089161 14992.4722 0.28 Polar Phenol 10.723 4417230 13012.9891 0.24 Polar Aniline 10.656 2402357 7077.2499 0.13 Polar Diphenyl sulfone 24.205 2228537 6565.1833 0.12 Polar Benzoic acid, methyl ester 12.851 1442987 4250.9838 0.08 Polar Propanoic acid, 2-methyl- 5.630 1007643 2968.4788 0.06 Polar Butanoic acid 6.674 1153406 3397.8898 0.06 Polar Pyridine 5.574 795184 2342.5815 0.04 Polar Decane 11.032 663244 1953.8903 0.04 Polar 1,2-Benzisothiazole 15.081 808685 2382.3559 0.04 Polar Pyridine, 2-methyl- 7.264 556197 1638.5340 0.03 Polar Butanoic acid, 3-methyl- 7.882 588330 1733.1969 0.03 Polar Benzyl alcohol, TBDMS derivative 8.741 294378 867.2268 0.02 Polar 2,5-Pyrrolidinedione, 1-methyl- 12.733 344595 1015.1630 0.02 Polar 2H-Benzimidazol-2-one, 1,3- 17.725 278915 821.6716 0.02 Polar dihydro-5-methyl- Butanoic acid, 2-methyl- 8.078 240862 709.5688 0.01 Polar benzoic acid, 4-(dimethoxymethyl)-, 8.370 257146 757.5435 0.01 Polar methyl ester Cyclohexanone 8.898 127497 375.6008 0.01 Polar 2-Cyclopenten-1-one, 2-methyl- 9.190 206981 609.7573 0.01 Polar 2-Cyclopenten-1-one, 3-methyl- 10.426 170331 501.7880 0.01 Polar N-Formylmorpholine 13.368 217272 640.0746 0.01 Polar Morpholine, 4-acetyl- 14.530 111425 328.2545 0.01 Polar 1,3-Benzenedicarboxylic acid, 19.023 265721 782.8038 0.01 Polar dimethyl ester 1,4-Benzenedicarboxylic acid, ethyl 20.011 74117 218.3462 0.00 Polar methyl ester TOTAL 1.29%

[0053] Precipitation of paraffin occurs over a range of 10-15 degrees C. for typical heavy oils until solidification occurs. The Cloud Point is the temperature at which crystals first appear in the oil. This temperature depends on the concentration, molecular weight of the paraffin and the chemical nature of the heavy oil. The Exotherm Area is the energy released at the time of crystallization.

[0054] To test the solution, 15.9 microliters of paraffin inhibitor 10 was added to an oil sample size of 10 milliliters, producing a 0.159% mixture. As a baseline, a straight crude oil sample was processed without additives to act as a comparison baseline.

[0055] Two oils from two different oil wells, Well A and Well B , were sampled and used for a test. The inhibitor solution lowered the cloud point. This testing used a 0.159% mixture. An increased mixture improves the performance. The oil samples showed differing cloud points reinforcing the need for concentration levels of the inhibitor solution high enough to treat varying conditions without having to match the inhibitor percentage to the paraffin content exactly. The results of tests are shown in TABLE 3.

TABLE-US-00003 TABLE 3 Well Additive Cloud Point C. Exo Area J/g A NoAdd 45.94 11.92 A P5 (0.159%) 40.73 15.46 B NoAdd 37.13 14.47 B P5 (0.159%) 35.05 12.17

[0056] In FIG. 2, enhanced oil recovery (EOR) is done in an oil field ground 12. The oil field ground 12 includes a production well 1 including core 21 extending in a well bore 121 down into the crude oil reservoir 122. An inhibitor injector 11 connects to and supplies an injection stream in piping 13 to transport an inhibitor down the core 21. A hot-oil injector 9 connects to and supplies an injection stream in piping 13 to transport hot oil down the core 21. The injection stream in piping 13, from either the hot-oil injector 9 or the inhibitor injector 11, or from both, is forced down the core 21 under substantial pressure.

[0057] In FIG. 2, the production well 1 includes a pump 20 connected through the well core 21 to the down-hole pump 22. Oil and gas is pumped from the down-hole pump 22 through the well core 21 for processing and storage in the oil unit 23 and the gas unit 24. An inhibitor injector 11 injects, through piping 13, an inhibitor 10 into the production well 11 or into the oil unit 23 or gas unit 24. The inhibitor increases the flow of ground oil from the ground and through all extraction system components including storage and transport components to help withdraw the oil from the ground and improve the flow of the oil throughout the extraction system components. When oil is transported to refineries or other locations using trucks, rail cars, pipelines or other equipment, inhibitors are useful particularly in cold areas.

[0058] When the production oil well 1 of FIG. 2 type is impeded by paraffin, an inhibitor solution is mixed with extracted oil for injection into the well 1 for treatment of paraffin. A few percent mix, for example 1%, of the inhibitor solution is mixed with extracted oil for injection into well 1. The inhibitor of TABLE 1 and TABLE 2 is mixed with extracted oil from well 1. A live well test included a hot oil application followed by a maintenance application using the inhibitor 10.

[0059] In FIG. 3, the chart reflects the production rate prior to the 56.sup.th day. On the 56.sup.th day, the well 1 was hot-oiled treated using 100 gallons of inhibitor 10. The production rate immediately increased as shown in AREA 1 when the paraffin restrictions were removed. When the paraffin restrictions were first removed, the pooled oil surrounding the pump was lifted out of well 1 at the high rate shown in AREA 1. When the oil quantity in the pool was decreased, the rate decreased to a continuous elevated flow, as represented by Area 2. After about day 136, the effect of the hot oiling application began to wear off as shown in AREA 3 until about day 190 when the flow returned back to the original rate. The chart of FIG. 3 shows that utilizing a well treatment procedure using inhibitor 10 succeeded in increasing the lift of the well 1.

[0060] While hot-oiling provides a remedy for a paraffin impeded well, it is desirable keep a well at higher production rates eliminating or reducing the need for hot-oil treatments. To achieve that goal, a maintenance procedure is employed. As shown in FIG. 4, positive results of higher flow rates occurred after hot-oil treatment of 50 gallons, smaller than the 100 gallon treatment of FIG. 3. The maintenance procedure involved injecting five gallons of inhibitor 10 twice per week. After the hot-oil treatment of day 50, the well 1 was allowed to settle out until the maintenance treatment began on day 140. The spikes in the chart of FIG. 4 showed some days production at an elevated rate with fluctuations of reservoir content causing the up and downs in the graph. Finally, on day 150, the maintenance treatment schedule was stopped to see the effects. There were some increased days of production that settled down by day 185 when the effects of the injected inhibitor 10 wore off. The chart of FIG. 4 shows successful production increases using a hot-oil treatment followed by maintenance treatments to establish a steady-state continuously higher flow rate of extraction for a well using the inhibitor 10. The production is typically measured in barrels per day (bbl/day).

[0061] The test of inhibitor 10 in hot oiling of a well were done to see how long the single blast of paraffin inhibitor 10 holds its ability to increase production. The initial production rate of 6.3 barrels per day for 50 days average with a spike as a result of the hot oil treatment using inhibitor 10. This spike is typical of most hot oil treatments, however, what resulted afterwards is of major interest. Most all hot oil treatments will have an immediate effect, however, how long the treatment lasts is more important. The initial treatment wore off in the matter of three weeks and settled in at a new high of 9.6 barrels per day average for almost two months. This well's history has included previous hot-oil treatments utilizing production oil and lasting less than 30 days. The trend line that is most important is that the output after the hot oil treatment wore off continued at a 3.3 barrel per day, or 52.4%, rate higher level with a trend line that was showing a slight increase. Equally as important, was the change in operation that took place. The pumping equipment experienced reduced start-stop activity that contributed to the increased production by reducing the opportunity for the crude oil to remain stationary and adhere to the pipe and equipment surfaces. The reduced electrical power needed for electrical motor start up is also significant. In summary, the whole system ran more efficiently.

[0062] In FIG. 5, the above-ground portion and the below-ground portion of the extraction system components 2 of a production well 1 are shown for pumping crude oil from the ground 12. An inhibitor injector 11 is shown for injecting an inhibitor 10 into the extraction system components 2 of production well 1. The extraction system components 2 of production well 1 include a pump 20 connected through the well core 21 to the down-hole pump 22. Oil and gas comes from the down-hole pump 22 through the extraction system components 2 of well core 21 for processing and storage in the oil unit 23 and the gas unit 24 which are part of the extraction system components 2. The inhibitor injector 11 injects, through piping 13, an inhibitor 10 into the extraction system components 2 of production well 1 or into the oil unit 23 or gas unit 24 and pipes 16 and 18 as controlled by valves 17 and 19. The inhibitor 10 pumped down the well core 21 to the down-hole pump 22 extends into the ground region 30-14 and the crude oil reservoir 122 surrounding the well bore pump 22. The inhibitor 10 increases the flow of ground oil from the crude oil reservoir 122 through the extraction system components.

[0063] The oil field ground 12 includes a ground formation including a number of layers 30-1, 30-2, . . . , 30-15. These layers, and specifically layers 30-9, 30-12 and 30-14, include ground oil and hence are variously called oil bearing formations or crude oil reservoirs. After primary and secondary recovery has occurred, often the ground oil can no longer be efficiently recovered using those methods owing to changes in temperature, pressure, crystallization or other conditions. To proceed with tertiary recovery, the injection stream of inhibitor 10 from the inhibitor injector 11 is forced into the core 21 and into the down hole-pump 22. The inhibitor 10 typically is forced into layer 30-14 and crude oil reservoir 122 in the region around pump 22. An exit stream of crude oil is withdrawn from the crude oil reservoir 122 of oil-bearing formation 30-14 through core 21 under the force of pump 20.

[0064] In FIG. 6, further details of the production well 1 and the injector 119 are shown. The injector 119 combines the inhibitor injector 11 and the hot-oil injector 9 of FIG. 5 which can be separate as shown in FIG. 5 or combined as shown in FIG. 6. The above-ground portion, designated as the pumping and distribution unit 100, and the below-ground portion of a production well 1 are shown for pumping crude oil from the oil field ground 12 and particularly from layer 30-14 holding the crude oil reservoir 122. An injector 119 is shown for injecting an inhibitor 10 into the production well 1. The production well 1 includes a pump 20 connected through the well core 21 to the down-hole pump 22. Oil and gas comes from the down-hole pump 22 through the well core 21 for processing and storage in the oil unit 23 and the gas unit 24. The injector 119 injects, through piping 13, an inhibitor 10 into the production well 1 or into the oil unit 23 or gas unit 24 and pipes 16 and 18 as controlled by valves 17 and 19. The inhibitor 10 pumped down the well core 21 by the injector 119 to the down-hole pump 22 extends into the surrounding ground in the pump region 101 including parts of the layer 30-14 and the crude oil reservoir 122. The inhibitor 10 increases the flow of ground oil from the ground through the extraction system components.

[0065] In FIG. 6, the pump 20 includes a prime mover 140 rotating a crank 47 connected to a Pitman arm 45 driving the walking beam 41. The walking beam 41 rotates and drives the horse head 42 up and down. The horse head 42 translates the bridle 63 up and down into the stuffing box 64 and translates the down-hole pump 22 up and down. Oil is pumped up the tube center 52 through the tee 65 into the pipe 28.

[0066] In FIG. 6, the core 21 typically includes a cement region 48, a casing 49, an annulus 50, lift tubing 51 and tube center 52. In the embodiment described, the inhibitor 10 is an inhibitor solution in an injection stream and is pumped by the injector 11 into the piping 25, through the valve 19, through the piping 26 to the annulus 50. The inhibitor 10 in the injection stream goes down piping 26 and annulus 50 to the region of the down-hole pump 22. The inhibitor 10 in the injection stream is forced through the openings (perforations) 62 into the pump region 101 within the layer 30-14 around the down-hole pump 22.

[0067] The injector 119, the piping 25, the tee 19, the piping 26, annulus 50, the pump 22, the tube center 52 of the lift tubing 51, T-valve 65, the piping 28, the valve 17 and the piping 27 connecting back to the injector 119 form a loop 120 for circulating the injection stream (including the inhibitor 10). The injector 119 through the loop 120 provides a continuous flushing of the injection stream through the loop 120 for solubilizing the paraffin. The continuous flushing acts to clear paraffin from any of the components in the loop and to decrease the viscosity of the crude oil. The continuous flushing functions to increase the production of crude oil in the production well.

[0068] Typically, the injector 119 will include a hot-oil truck that is driven to the location of the production well. The hot-oil truck includes pumps, storage tanks and heaters for processing the injection stream. The pumps can apply increased pressure and temperature to the processing of the injection stream. The injection stream is heated in a range from ambient temperature up to 300 C. or more. The pressure of the injection stream is increased sufficient to force the injection stream including inhibitor 10 down to the pump region 101. For example, a normally pressured reservoir, assuming a given area's water gradient of 0.43 psi/ft and a depth of 4000 feet, could be about 1,700 psi. Therefore, the pressure of the injection fluid would need to be increased to greater than 1700 psi to reach the target reservoir. However, the required pressure can differ as a function of the particular production well being treated.

[0069] The mixing of the inhibitor solution with the crude oil from the production well is typically done in the inhibitor 110. The mixing in one embodiment has the inhibitor solution 0.15% or greater of the crude oil of the production well and is effective to raise the Cloud Point temperature of the crude oil. In FIG. 7, the up stroke of the bore pump 22 is shown. The traveling valve 53 travels up from the position 53 to the position of traveling valve 53 and causes the ball 55 to seat into the opening 58 preventing any crude oil from passing through the opening 58 while pushing crude oil up the core 21 and particularly up the tubing center 52. The standing valve 54 has the ball 56 open allowing crude oil to enter chamber 61 from the oil-bearing formation 30-14 as the up stroke of the bore pump 22 occurs.

[0070] In FIG. 8, the down stroke of the bore pump 22 is shown. The traveling valve 53 travels down from the position 53 to the position of traveling valve 53 and causes the ball 55 to unseat from the opening 58 allowing crude oil upward into the chamber 61 passing through the opening 58 while preventing crude oil from exiting the chamber 61 because the standing valve 54 has the ball 56 closed as the down stroke of the bore pump 22 occurs.

[0071] When the conditions for wax formation exist for the oil-bearing formation 30-14, a wax formation may occur anywhere in the crude oil path from openings 62, in the bore pump 22, in the tubing 51, and the tubing 16. In the embodiment of FIG. 6, the inhibitor injector valve 19 is open to permit inhibitor 10 to flow down piping 25 and piping 26 to the annulus 50, through the openings (perforations) 62 and into the oil-bearing formation 30-14 and the bore pump 22. The operation of the bore pump 22 tends to push the crude oil mixed with inhibitor 10 up the tubing center 52. In the embodiment shown in FIG. 6, the valve 17 is open to the oil unit 23 through line 16 and is closed to the 119. In an alternate connection, the valve 17 is open to allow inhibitor 10 to be forced down the piping 27, the piping 28, the tubing center 52 toward the bore pump 22. The valves 17 and 19 are controlled to allow the fluid of inhibitor 10 to be forced down either the annulus 50, the tubing center 52 or both.

[0072] At times, crude oil from the oil unit 23 of production well 1 of FIG. 6 is pumped over long-distance pipe lines 29 to a remote oil unit 123. The pipe line 29 can be adversely affected by wax build up, particularly when the pipe lines 29 is in a cold environment. The valve 117 is opened to permit pumping of an inhibitor 10 through pipe 117 into the pipe line 29 and to remote oil unit 123 to help prevention of wax and asphaltenes formation.

[0073] A primary parameter for recovery of hydrocarbons from the oil-bearing formation 30-14 is the critical temperature referred to as the Wax Appearance Temperature (WAT). The WAT for the oil-bearing formation 30-14 can vary with oil composition, cooling rate, pressure, paraffin concentration, molecular mass of paraffin molecules, occurrence of nucleating materials such as asphaltenes, formation fines, and corrosion products and water/oil ratio. Since the temperature cools as the depth below-ground level decreases, the WAT can be reached anywhere from the region of the bore pump 22 and upward in the tubing 51 or any piping upstream therefrom. For example, cold water in strata surrounding the tubing causes cooling.

[0074] The prevention of wax formation using inhibitors enhances oil flow by improving flow rates. A high flow rate tends to minimize wax adherence to metal surfaces because of the shearing action of the flowing fluid. The metal surfaces in FIG. 6 where wax adherence can occur include the bore pump 22, the tubing 51, the T-valve 65, the piping 28, the valve 17, the piping 16. Additional metal surfaces appear in the oil unit 23, the remote piping 29 and the remote oil unit 123. If the remote piping 29 is in cold climates, the need for inhibitors is increased.

[0075] The inhibitor 10 inserted into the oil flow conduits of FIG. 6 includes the non-polar components 14 of FIG. 1 and TABLE 1 and the polar components 15 of FIG. 1 and TABLE 2. The insertion of the inhibitor 10 occurs anywhere over the flow stream of the crude oil.

[0076] In FIG. 9, further details of another production well 1 similar to the well of FIG. 6 is shown. The well includes the above-ground portion, designated as the pumping and distribution unit 100, and the below-ground portion of a production well 1 including the pump region 101. The core 48 connects between the pumping and distribution unit 100 to the down-hole pump in the pump region 101 around the pump 22. The core 48 has a bend allowing the pumping region to be offset a substantial lateral amount from directly below the pumping and distribution unit 100. In the example of FIG. 9, the bend is approximately 90 with a typical radius of about 900 feet.

[0077] In FIG. 10, a pyrolysis apparatus 70 is shown for producing an inhibitor 10. The pyrolytic system 70 has a load station 71, a pyrolysis station 72, an unload station 73 and a control unit 83. The pyrolysis apparatus 70 includes a transportable cart 75 for moving along a transport track 84 or along other transport paths. The transport track 84 extends to each of the load station 71, the pyrolysis station 72 and the unload station 73. In the load station 71 scrap tires 74 or other materials for pyrolysis are loaded onto transportable cart 75 for transport along the track 84 to the pyrolysis station 72.

[0078] The pyrolysis station 72 has a pyrolysis furnace 90 for receiving the transportable cart 75 and the scrap tires 74. The furnace 90 includes a heat unit 78 for heating the furnace 90 to pyrolysis temperatures. The heat unit 78 connects to heaters 76-1 and 76-2 within the furnace 90 where they operate to heat the pyrolysis chamber 92 to the batch pyrolysis temperatures greater than 780 C. and up to 1100 C. or more.

[0079] Before the pyrolysis operation, the scrap tires 74 or other materials are on the transportable cart 75. After pyrolysis, the pyro-solids 77 remain on the transportable cart 75 and are transported to the unload station 73. The entry and exit of the transportable cart 75 into and from the chamber 92 of furnace 90 is through a door 93 in the wall of the furnace 93. The door 93 is opened to receive the transportable cart 75 from the load station 71, is closed and sealed during the pyrolysis operation and thereafter is opened to allow transport of the cart 75 and pyro-solids 77 to the unload station 73.

[0080] The pyrolysis station 72 includes a vapor unit 79 that connects via the piping 82 (vapor transfer line) to the furnace 90 to convey the vapors resulting from the pyrolysis operation. The vapor unit 79 connects by piping 83 to the oil unit 80. The oil unit 80 connects by piping 82 to the inhibitor storage 81 which stores the inhibitor 10 produced by the pyrolysis operation.

[0081] The pyrolytic system 70 receives scrap tires 74 or other material as inputs and performs batch pyrolysis processing to produce pyro-products as outputs. The pyro-products produced include pyro-vapors on piping 82 (vapor transfer line) that are condensed into pyro-oil in the condenser of the vapor unit 79 and pyro-gas that survives the condenser and includes pyro-solids 77 that are principally pyro-carbon.

[0082] One important example of carbon based polymeric materials for pyrolysis are used tires, typically from automobiles, trucks and other vehicles. The pyrolysis of tires results in, among other things, a carbon residue of pyro-solids (char), pyro-oils and pyro-gases. The composition of pyro-solids, pyro-liquids and pyro-gases is determined by the materials that are used to manufacture tires. The principal tire materials used to manufacture tires include rubber (natural and synthetic), carbon black (to give strength and abrasion resistance), sulfur (to cross-link the rubber molecules in a heating process known as vulcanization), accelerator metal oxides (to speed up vulcanization), activation inorganic oxides (principally zinc oxide, to assist in the manufacture of tires. The tire materials are mixed forming a homogenous green tire including carbons and oxides. The green tire is transformed into a finished tire by a curing process (vulcanization) where heat and pressure are applied to the green tire for a prescribed cure time.

[0083] When tires are discarded, they are collected for pyrolysis processing to reclaim useful components of the tires where the useful components are the tire materials used to form the green tires. In general, tire pyrolysis involves the thermal degradation of the tires in the absence of oxygen. Tire pyrolysis is used to convert tires into pyro-materials including pyrolysis gases (pyro-gases), pyrolysis oils (pyro-oils), and pyrolysis solids (pyro-chars) including ash and steel. A by-product of the pyrolysis process is the generation of a substantial amount of heat that can be used for cogeneration or other purposes. To enhance value, pyro-materials can undergo additional processes after the pyrolysis is complete.

[0084] The chemical and physical composition of the pyro-gases, pyro-oils, and pyro-chars after pyrolysis differ from the composition of the tires before pyrolysis. Also, the form of the pyro-gases, pyro-oils, and pyro-chars after pyrolysis differ from the solid form of the tires before pyrolysis.

[0085] The pyro-gases include processed pyro-gas, combustion gases (such as CO, C0.sub.2), helium, nitrogen, and hydrocarbon gasses, sulfur containing hydrocarbon gases, other by-products derived from the pyrolysis process including gases such as vapor-phase metals. The pyro-solids are materials including char that contain a number of inorganic materials, including materials such as metal sulfides and metal oxides (often referred to as ash) and carbon. Solids can be introduced into the injection stream in piping 85 and the solids can include post-processed char that has been externally milled or modified. The liquids include pyro-oil, a number of hydrocarbons and other liquids such as liquids that contain dissolved inorganic metals. The liquids can also include solubilizing agents such as sulfur containing hydrocarbons and other by-products derived from the pyrolysis process.

[0086] One of the important products of the pyrolysis process is an inhibitor 10. The inhibitor 10 includes both polar and non-polar compounds which are useful as dissolving agents to help reduce the adverse effects of paraffin.

[0087] While the invention has been particularly shown and described with reference to preferred embodiments thereof it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention.