US2904485A - Radiochemical treatment of heavy oils - Google Patents

Description

Sept. 15, 1959 Filed June 21, 1956 HEAVY HYDROCARBON OIL IRRADIA'HON WATER SOLVENT l 5 EXTRACTION A WATER 8- WASH AIDS SEPARATION PRODUCT Barry L. Tarmy Robert 8. Long Inventors By 02? Attorney Y United States Patent 2,904,485; D WtEM C L HEAVY S- Barry: L. Tarmy, Cranfond, and. Robert B.. Long, Wanamassa, ,N.J;., assignors, to. Eesojliesearch and Engineera 9 2mm e e ating-9 Del wa e- Application June 21, 195 s e r No, sszpse 4.- Claims, oi. 204-4541 the extent thatthe fraction'rece es.a. osage'in, the-range 2,904,485 Patented Sept. 15, 1959 1 A nuclear reactor such as. an atomic pile. can. be the radiation, source- Generally speaking, a: much higher level ofirradiation is, obtainable and thus. the irradiation times, can. be. reduced. In this embodiment of the. in-. vention,, besides. the above level ofgamma. ray flux, it is preferred. that th neutron flux at, the point. of irradiaa tion be above about 10 neutrons/cm. /sec.. The. total radiation dosage is maintained, in the. rangeof 3.6.. to. 3600 B.t.u.s/.lb. i

. When using, a nuclear reactor, the heavy Oil. is. simply pumped throiughpipes. disposedin. or around the 555mm able material. Heterogeneous or homogeneous reactors. can: be. used. f Conventional moderators such. as carbon, lightv and heavy water; or hydrocarbons can. be used. to control the energy of the neutrons. the hydroearbonreactant. can serve as a; moderator.

The temperature during, irradiation is, generally below.

' thermal conversion temperatures, i.e.,, below 700.? F.,

preferably below 5,0091% While. high pressures can be,

used, the'pressureusuallyis inthe rangeof 0'to.50 p.s.i.g., The. time. of treatmentto receive. the. above. dosages. is

. nonnally, in the range. fo 0.0L to. 5000.. min. Conversion.

of 10 to 10 'rnegaroentgens, and then'washihg are-rm.

tion so treated with water. The temperature oftreatment is preferably under 500 F., and the conditions are such that less than 5 wt. percent of the oil is converted to C materials, including coke.

This invention is concerned with oils that contain an appreciable amount of heavy material such as asphaltenes, naphthenic acids, and the like, that result in the formation of water-oil emulsions. For the purpose of this invention, such heavy oils are defined as oils containing at least 5% of constituents non-vaporizable at atmospheric pressure without cracking, and include whole crudes, residua therefrom, shale oil, coal tars, asphalts, and similar materials.

In many cases it is desirable to treat heavy oils with water or an aqueous medium to remove salts or similar contaminates. With many oils, the heavier portions are responsible for forming stable water-oil emulsions. Severe and repeated treatments may be required to break these emulsions.

It has now been found that when a heavy oil is sufi'iciently irradiated, especially with gamma rays prior to treatment with water, the tendency of the oil to form water-oil emulsions is at least substantially reduced, if not eliminated. An important feature of this invention is that only a relatively small dosage is required to achieve this effect, compared to other types of hydrocarbon radiochemical reactions.

The following description of the drawing attached to and forming a part of this specification will serve to make this invention clear.

As illustrated, a heavy hydrocarbon oil from source 1 is introduced into a radiation reaction zone 2 by line 3. The irradiation, including charged particles and photons, provided in radiation source 2 can be obtained from artificial accelerators, nuclear'waste products, or products especially made radioactive by insertion in nuclear reactors such as cobalt 60, the use of radio-isotopes being preferred. In this preferred form of the invention, the average gamma ray flux in the reaction zone is better than 10 Roentgens/hr. It is also preferred that the conditions be such that the heavy hydrocarbon oil receive a dosage of 10 to 10 megaroentgens. The material is exposed to the radiation source simply by flowing it in pipes past or through the radioactive material.

off the .oil, is maintai iledv below 5. percent: to 'C js, ifs t mthane.,,hvdrog an o After this irradiation treatment, the heavy oil. is. ad-.

mixed, i desired, with, asuitable organie. solvent such 1 as, benzene pyridine, phenols, glycols, resorcinols,,. and,-

mixtures thereof, supplied from source. '4, byfjline S; Then it is treated with water supplied by line 6. from source] toremove salts,; me tals,. andIotherl contaminates, and passed to zone 8. Customary water washing techniques are used in zone 8. The amount of water used varies from 0.5 to 10 lbs/lb. of heavy oil. Conventional pressures and temperatures are used, e.g., 0 to 400 p.s.i.g., and 60 to 400 F. This water washing zone can, of course, consist of several stages or can operate countercurrently in manners well known in the art.

During the water washing, well known materials, here called extraction aids, supplied by line 9 from source 10, can be used to facilitate the removal of the contaminates and other materials. These extraction aids include, for example, strong inorganic acids such as HCl, H H PO H 8, and hypochlorites.

After the water treatment, the treated heavy oil is passed by line 11 to separation zone 12, here shown as being separate from zone 8, but separation can, of course, occur in zone 8. If a separate separation stage is used, this can include well known separating means such as settling, stripping, distillation, adsorption and absorption. The recovered aqueous medium, solvent and/ or extraction aid is rmoved by line 13 and can be recycled if desired. The treated heavy oil is removed by line 14.

Example A 900+ F. Bachaquero residua was subjected to 120 megaroentgens of gamma irradiation at F., and 16.7 megaroentgens at temperatures of 450 and 650 F. The samples were then dissolved in benzene and treated with water, aqueous pyridine and dilute HCl. The samples were easily washed with the aqueous medium without any water emulsions being formed. In contrast, the original feed and the feed that was subjected to elevated temperatures for the same length of time without radiation, formed stable emulsions which required hydrochloric acid and repeated heat shock treatment to be broken. Even with these treatments, it was not possible to completely remove all the water in the non-irradiated samples.

More particularly, the Bachaquero residua had the following inspections: boiling point 900 F.|-, sulfur 3.26 wt. percent, modified naphtha insolubles 18.2 wt. percent, and specific gravity 1.022.

In some. cases The samples were irradiated by exposure to a cobalt 60 source having a strength of about 3100 curies. Two 500 ml. bombs, one containing 403 gr. and the other 396 gr. ofBachaquero residuum, were placed at a distance of about 4 inches from the cobalt 60 source and heated to 450 F. and 650 F. respectively for 116 hours at a gamma dose rate of about 144,000 Roentgens/hr. Simultaneously a 143 gr. sample was placed in the high intensity center of the cobalt 60 source, absorbing gamma radiation at a rate of about 103x10 Roentgens/hr. at an ambient temperature of about 120 F. A line led from each bomb to a knockout trap to catch any liquid that might come over, and then to a gas meter and sample bomb. Duplicate runs were also made without radiation. All radiation runs produced some gas, while substantially no gas was obtained without radiation. During the 650 F. run, some liquid was obtained in the knockout trap.

The irradiated samples were first dissolved in benzene (2 parts benzene1 part residuum) to obtain a liquid that would flow easily. The samples were then washed with water parts total water to 1 part residuum solution). The irradiated samples did not emulsify while the non-irradiated samples did. The samples were further treated .with HCl and pyridine, and filtered. The emulsions from the non-irradiated samples were almost completely, but not quite, broken with a repeated heatshock and HCl treatment.

Having described the invention, what is sought to be protected by Letters Patent is succinctly set forth in the following claims.

' What is claimed is:

l. A process for pretreating a heavy petroleum oil containing a substantial proportion of constituents nonvaporizable at atmospheric pressure without cracking, whereby the propensity of the heavy petroleum oil to form stable emulsions when subsequently treated with an aqueous medium is substantially reduced, which comprises irradiating said heavy petroleum oil with gamma radiation to a total dose in the range of 10 to 10 megaroentgens, and under conditions such that less than 5 weight percent of said heavy petroleum oil is converted to C s, C s, methane, hydrogen and coke, and then contacting the heavy oil so treated with an aqueous medium.

2. The process of claim 1 wherein said radiation is obtained from a radio-isotope.

3. The process of claim 1 wherein the temperature during irradiation is maintained below 500 F.

4. The process of claim 1 wherein said oil after irradiation is first admixed with an organic solvent.

References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES Mincher: A.E.C. Document KAPL-73l, pages 3-8. Apr. 2, 1952. Declassified Feb. 15, 1955.

Riegel: Industrial Chemistry, 2d edition, pages 362- 383 (1933).

Claims (1)

1. A PROCESS FOR PRETREATING A HEAVY PETROLEUM OIL CONTAINING A SUBSTANTIAL PROPORTION OF CONSITITENTS NONVAPORIZABLE AT ATMOSPHERIC PRESSURE WITHOUT CRACKING, WHEREBY THE PROPENSITY OF THE HEAVY PETROLEUM OIL TO FORM STABL EMULSIONS WHEN SUBSEQUENTLY TREATED WITH AN AQUEOUS MEDIUM IS SUBSTANTIALLY REDUCED, WHICH COMPRISES IRRADIATING SAID HEAVY PETROLEUM OIL WITH GAMMA RADIATION TO A TOTAL DOSE IN THE RANGE OF 10 TO 103 MEGA-

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