US20040089321A1

US20040089321A1 - Supercritical fluid cleaning systems and methods

Info

Publication number: US20040089321A1
Application number: US10/291,234
Authority: US
Inventors: Lyndon Stone
Original assignee: Varco IP Inc
Current assignee: Varco IP Inc
Priority date: 2002-11-08
Filing date: 2002-11-08
Publication date: 2004-05-13
Also published as: GB2410704B; NO20051399L; CA2498964A1; WO2004041400A2; GB2410704A; AU2003264897A8; AU2003264897A1; GB0505153D0; WO2004041400A3

Abstract

A process for cleaning a material with a cleaning system having system apparatus and at least one electronic device associated with the system apparatus, the at least one electronic device having a specified temperature operation range, the system having contacting apparatus, the process including contacting a material with an extracting fluid under conditions of temperature and pressure sufficient to maintain the extracting fluid at, near or above its critical point to produce a clean material, flowing the extracting fluid from the contacting apparatus to pressure reducing apparatus to lower pressure of the extracting fluid, lowering the pressure of the extracting fluid with the pressure reducing apparatus, thereby cooling the extracting fluid producing cooled extracting fluid, and flowing the cooled extracting fluid in heat exchange relation with the at least one electronic device to maintain temperature of the at least one electronic device within the specified temperature operation range; and a system for effecting such temperature maintenance.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is directed to systems and methods for separating constituents of a mixture and thus cleaning materials using supercritical or near-supercritical fluids.

2. Description of Related Art

The prior art discloses a variety of methods and systems for using supercritical fluids to separate and to remove selected constituents of a compound material.

Many prior art extraction processes using supercritical fluids or pressurized liquids consist of using a fluid under adequate pressure and temperature conditions to give the fluid an increased dissolving capability. With supercritical fluids, the pressure and temperature conditions are such that the pressure is above the critical pressure and the temperature is above the critical temperature. An “extraction fluid” is a supercritical fluid or pressurized liquid under such temperature and pressure conditions.

Certain benefits can be obtained by using supercritical fluids as compared with using pressurized liquids. Supercritical fluids have a relatively low viscosity and high diffusivity, which leads to high extraction kinetics.

The prior art discloses a variety of fluids that can be used in supercritical fluid extraction processes. In certain situations carbon dioxide is used because it is non-toxic and causes no particular problems. Its critical temperature and pressure are not very high, corresponding to 31° C. and 7.3 MPa.

In certain prior art processes a substance containing constituents to be extracted is introduced into an extractor vessel and is brought into contact with an extraction fluid at a desired temperature and pressure. The extraction fluid dissolves certain components of the substance. On leaving the extractor vessel, the extraction fluid containing dissolved constituents is collected in a separator vessel, the pressure of the extraction fluid is lowered, allowing it to change to a gaseous state which makes it possible to collect the extraction fluid in gaseous form and to collect the extracted constituents in liquid form. On leaving the separator, the gaseous phase is then re-compressed changing it to a liquid state for recycling to the extractor.

Certain prior art processes use two-stage expansion. First the fluid is expanded to a pressure intermediate between atmospheric pressure and the pressure used in the extractor, followed by the separation of the liquid constituents from the expanded gaseous phase, then the gaseous phase is expanded to atmospheric pressure and the liquid constituents separated from said gaseous phase in a second separator, e.g. a cyclone.

U.S. Pat. No. 4,434,028 discloses method and apparatus for removing oil and other hydrocarbon and/or organic constituents from contaminated drill cuttings. Cuttings to be treated are transferred into a pressure vessel wherein they are contacted with an extractant which is normally a gas but is under conditions of pressure and temperature to provide the extractant in a fluid solvent state (in one aspect, in a supercritical state) for the constituents to be removed, whereby the constituents are transferred to the extractant. The extractant containing the constituents is withdrawn from the pressure vessel and depressurized to render it a nonsolvent for the constituents and to form a two-phase system which is then separated into extractant for repressurizing and recycling with proper handling of the constituents removed. In the case of removing oil from drill cuttings, the essentially oil-free cuttings can be disposed of in any suitable manner including dumping overboard from an offshore drilling rig.

U.S. Pat. No. 4,824,570 discloses apparatus for the extraction of constituents present in a substance by means of an extraction fluid constituted by a supercritical fluid or a pressurized liquid. Contacting takes place in an extractor between the substance and the extraction fluid in order to dissolve the constituents in fluid. The fluid leaving the extractor is then treated to separate the extracted constituents. First, the less volatile constituents are separated in a liquid-gas separator, the separated gas is then liquefied in a gas separator-liquefier and the thus liquefied gas is rectified in a column to concentrate the extracted constituents in the liquid phase. The extraction fluid can be carbon dioxide gas.

Many prior art fluid cleaning/extraction systems and methods employ a variety of electronic devices to monitor and control processes. Often such devices are cooled to maintain their temperature within a specified operating range. The present inventor has recognized solutions to the problem of cooling and maintaining such electronic apparatuses at a temperature within a desired operating range.

SUMMARY OF THE PRESENT INVENTION

The present invention, in certain embodiments, discloses methods and systems for using supercritical fluid (or nearly supercritical fluid, or fluid above supercritical levels) to separate components of a material and to selectively clean material to remove undesired constituents. Although the present invention is not limited to cleaning any particular material or to separating the constituents of any specific compound material or mixture, it is, in certain aspects, useful for cleaning drilling cuttings contaminated with hydrocarbons, e.g., but not limited to, hydrocarbon-contaminated drilling mud (e.g. oil-based, water-based and synthetic-oil-based muds).

In certain embodiments a fluid is brought to (or near or above) a supercritical state and fed as an extractant into an extractor. Material to be treated is fed into the extractor. Treated material flows from the extractor. Extractant with one or more constituents of the material flows from the extractor. Extractant is then separated from the one or more constituents for re-use and/or disposal. The separated constituents are re-used, treated further, further separated, and/or disposed of.

In such a system various electronic devices are used to monitor and control the process. For example, and not by way of limitation, a variety of electronic devices can be used, e.g. programmable logic controllers; computers; bus-interface devices; and signal conditioners for receiving, conditioning and retransmitting signals from pressure sensors, temperature sensors, flow sensors, level sensors; and limit switches. According to the present invention, to maintain such electronic devices at a relatively cool operating temperature, fluid exiting the extractor is introduced to a pressure reduction apparatus, e.g., but not limited to a pressure-reducing valve apparatus or a pressure-reducing orifice device. In reducing the pressure of the fluid, there is a cooling effect. A heat sink or a temperature exchange apparatus in fluid communication, physical contact, or heat-exchange relation with the pressure reducing apparatus or device produces a relatively cold temperature (e.g. in a conduit and/or on a surface of a member or part). The heat exchange apparatus or device is positioned with respect to the electronic device(s) to maintain a desired temperature in the environment of the electronic device(s). The supercritical (or near or above supercritical) fluid from the extractor that flows to the pressure reducing apparatus or device is then fed back into the system for further treatment, processing, separation, and/or re-sue.

In one particular aspect the supercritical (or near or above supercritical) fluid is carbon dioxide. In one particular aspect the material to be treated is wellbore drilling cuttings contaminated with hydrocarbons (e.g., but not limited to oil-based drilling mud, petroleum, synthetic oil, and/or hydrocarbon materials). In certain aspects processes according to the present invention are batch processes and in other aspects they are continuous processes.

Alternatively, fluid at sufficient pressure from any point in the system may be fed to a pressure reducer to produce a cooling effect for cooling electronic devices.

It is, therefore, an object of at least certain preferred embodiments of the present invention to provide:

New, useful, unique, efficient, non-obvious systems and methods using supercritical (or near or above supercritical) fluids and related apparatuses and equipment used with associated electronic devices that are maintained in an environment at a desired operating temperature;

Such systems and methods wherein fluid in a process fluid stream is depressurized to produce sufficient cooling to maintain the desired temperature;

Such systems and methods wherein the electronic devices include, but are not limited to, programmable logic controllers; computers; bus-interface devices; and signal conditioners for receiving, conditioning and retransmitting signals from pressure sensors, temperature sensors, flow sensors, level sensors; and limit switches; and

Such systems and methods useful in cleaning hydrocarbon-contaminated wellbore drilling cuttings, e.g. contaminated with oil-based drilling fluid, petroleum, synthetic oil, and/or hydrocarbon contaminants; and

Such systems and methods for producing contaminant-free (nearly contaminant-free) drilling cuttings.

The present invention recognizes and addresses the previously-mentioned problems and long-felt needs and provides a solution to those problems and a satisfactory meeting of those needs in its various possible embodiments and equivalents thereof. To one of skill in this art who has the benefits of this invention's realizations, teachings, disclosures, and suggestions, other purposes and advantages will be appreciated from the following description of preferred embodiments, given for the purpose of disclosure, when taken in conjunction with the accompanying drawings. The detail in these descriptions is not intended to thwart this patent's object to claim this invention no matter how others may later disguise it by variations in form or additions of further improvements.

DESCRIPTION OF THE DRAWINGS

A more particular description of certain embodiments of the invention may be had by references to the embodiments which are shown in the drawings which form a part of this specification. [0025]
FIG. 1 is a schematic view of a system according to the present invention. [0026]
FIG. 2 is a schematic view of a system according to the present invention. [0027]
FIG. 3 is a schematic view of a system according to the present invention. [0028]
FIG. 4 is a schematic view of a system according to the present invention.[0029]

DESCRIPTION OF EMBODIMENTS PREFERRED AT THE TIME OF FILING FOR THIS PATENT

FIG. 1 shows a [0030] system 10 according to the present invention with an extraction vessel 12 with upper and lower portions 14 and 16, respectively. Material to be treated is introduced into the vessel 12 through a conduit 18. Optionally, fluid in the conduit 18 may be heated to a desired temperature by any suitable known heating apparatus and/or heat exchanger. Such a heat exchanger may be in heat exchange relation with any item, line, or conduit in the system for transferring heat therefrom to the conduit 18. In one particular aspect material in the conduit 18 is heated to a temperature near an extraction temperature within the extraction vessel 12.
Optionally, an inert gas may be introduced into the extraction vessel [0031] 12 as a purge gas, e.g. as described in U.S. Pat. No. 4,341,619 incorporated herein fully for all purposes. A control valve 30 selectively controls material flow in a conduit 26 from the bottom 16 of the extraction vessel 12; e.g. cleaned material exits the vessel 12 in the conduit 26, e.g., but not limited to, cleaned wellbore drilling cuttings previously contaminated with petroleum material and/or hydrocarbons.
Extractant (e.g., in one aspect, carbon dioxide in a supercritical state) is pumped in a [0032] conduit 32 to a conduit 33 by a pump/compressor apparatus 34 which reduces the input pressure of the carbon dioxide, e.g. (in one particular aspect) from about 700 p.s.i. to about 3500 p.s.i. The apparatus 34 is also referred to as an “intensifier.” Reclaimed extractant flows in a conduit 38 to the conduit 33 for re-use in the extraction vessel 12. Optionally, the conduit 33 may be in heat exchange relation via a suitable heat exchange apparatus with the material flowing out in the conduit 26. Also optionally, the material in the conduit 33 is heated by a heater 36 and then introduced into the extraction vessel 12.
An extract stream including extractant and extracted material (and purge gas, if present), flows out from the extraction vessel [0033] 12 in a conduit 58 through a pressure-reducing valve 30.
Extractant in the [0034] conduit 58 is at, near or above a supercritical state and is at a relatively elevated pressure. Upon passing through the pressure reducing valve 30, the temperature of the material in the conduit 58 is significantly reduced (flowing into the conduit 22) and, in certain aspects, is reduced to a temperature sufficient to maintain electronics in an electronic apparatus 60 at a desired operating temperature. A cooling apparatus 62, e.g., but not limited to a cooling jacket, coil, or heat sink is adjacent to, encompasses (as shown in FIG. 1) and/or surrounds the electronic apparatus 60. When the cooling apparatus 62 includes an enclosure housing the electronic apparatus 60, the pressure-reducing valve 30 (or as may be the case in any embodiment of the present invention a pressure-reducing orifice device) may be located within the enclosure, temperature may be maintained simply by passing part of the conduit 22 through the enclosure or by using a heat exchanger or heat sink within the enclosure in fluid communication with or near the conduit 22. Optionally, a pump 64 pumps the extractant from the conduit 22 into a conduit 42 through a valve apparatus 44 (which may be, in one aspect a piloted valve) through a heat exchanger 46 to a separator 48 (or the pressure difference alone in the systems moves the extractant through the system). The separator 48 separates extractant which flows in a conduit 50 through a valve 56 (optionally, to a pump 54) to the line 33 for re-use in the extraction vessel 12. Separated material flows from the separator 48 in a aline 52. Optionally, instead of a separator 48, two flash chambers as shown in U.S. Pat. No. 4,341,619 with their associated apparatuses, conduits, and equipment may be used. Carbon dioxide is supplied from a tank, vessel, or reservoir 80 to the line 33.
According to the present invention, each, some, or every item, conduit, vessel, pump, valve, apparatus, and piece of equipment in the system may have associated with it a temperature sensor t, a pressure sensor p, a qualitative sensor or measurement device or apparatus [0035] 1, and/or an operating mechanism or activator o. Such item or items, etc. are in communication with the electronic apparatus 60 which may be, but is not limited to, one or more controllers, programmable logic controllers, computers, or electronic processing and/or control devices or apparatuses. Such communication is indicated by the dotted lines between the electronic apparatus 60 and one pressure sensor p, one temperature sensor t, one qualitative sensor q, and one operating mechanism o, but it is to be understood that every sensor p, t, q and every mechanism o are similarly connected to and in communication with the electronic apparatus 60. It is within the scope of this invention for each sensor t, p, q and each operating mechanism o to have its own cooling apparatus (like the cooling apparatus 62) in fluid communication with the output of a pressure reducing apparatus [like the pressure reducing valve 30 or the valve 30 and associated conduit(s) may be used]. Thus the system can maintain a desired operating temperature for any electronic apparatus in the system. It is within the scope of the present invention to thus provide such a temperature environment for any item or items, etc. in any supercritical (or near or above supercritical) fluid extraction process.
As shown in FIG. 1 the electronic apparatus [0036] 60 may, according to the present invention, be in communication with transmitting equipment 70 which provides communication between the electronic apparatus 60 and offsite apparatus 72. Thus an offsite location may constantly monitor in real time any item, etc., of the system 10 and/or control any such item, etc. The offsite apparatus 72 may include, but is not limited to, one or more computers, data receivers, data processors, servers and/or networks. In one aspect the transmitter 70 places the electronic apparatus 60 and the offsite apparatus 72 in communication via the Internet. Any system according to the present invention may have such a monitoring and/or control function and associated apparatus, etc.
In one particular embodiment, the material being treated is wellbore drilling cuttings contaminated with hydrocarbons, e.g., but not limited to, with oil-based drilling fluid, petroleum material, and/or hydrocarbons, and the electronic apparatus [0037] 60 and/or the offsite apparatus 72 constantly monitors the level of contaminants, if any, in the material flowing from the extractor in the conduit 26 as indicated by a qualitative sensor q on the conduit 26 (and such monitoring and associated sensor and conduit may be used in any system described herein).
FIG. 2 shows a system and [0038] method 100 according to the present invention in which drilled mud containing cuttings is fed to a first separator 102, “Separator I,” which produces mud free of cuttings (which can be re-used) and oil-contaminated cuttings. Optionally, the oil contaminated cuttings are processed through a crushing apparatus 104, “CRUSHER,” or other suitable mill or apparatus for reducing them in size and/or rendering them more easily treated and capable of being made into a slurry. The cuttings are introduced to a slurry forming apparatus 106, “SLURRY FORMER,” into which a slurry-forming liquid is fed. A pumpable slurry and an extractant are pumped to an extraction vessel 108, “EXTRACTOR,” which produces clean cuttings and an effluent that includes extractant. The effluent is pumped (and/or flows simply by pressure differential) to and through a pressure reducing apparatus 110 which provides cooled fluid to a cooling apparatus 112 around or near an electronic apparatus 114. The cooling apparatus 112 maintains a desired operating temperature in the environment of the electronic apparatus 114. The extractant flows from the cooling apparatus 112 to a separator 116, “SEPARATOR 11,” which produces re-usable extractant which is pumped back to the extraction vessel 108 and oil (and/or other contaminants) which is pumped to storage, disposal, and/or further treatment apparatus. The extractant is, preferably, a supercritical fluid and appropriate apparatuses and equipment are used to produce and maintain supercritical fluid conditions for both the input and recycled extractant (as may be done for any system according to the present invention).
In a manner similar to that of the [0039] system 10 described above every (and any) item, conduit, apparatus and piece of equipment in the system 100 may have associated sensor(s) t, p, q and/or operator(s) o which are in communication with the electronic apparatus 114 (like the electronic apparatus of the system 10). Any or all of the teachings of the present invention may be incorporated into systems and methods as disclosed in U.S. Pat. No. 4,434,028 incorporated fully herein for all purposes.
FIG. 3 shows a [0040] system 200 with four extraction vessels 208, 210, 212, 214 in parallel, each receiving supercritical extractant via lines E1, E2, E3, E4, respectively from a main line ML from a source 202.
An [0041] intensifier 226 treats fluid, e.g. carbon dioxide, from the source 202, to raise it to or near a supercritical state. Heat from this fluid is taken off by a heat exchanger 204 to provide heat to reactor heat exchangers HE in each vessel 208, 210, 212, 214. Extractant fluid is, optionally, maintained in a vessel 206. A valve VL selectively controls pressure in the line ML.
Cleaned drilled cuttings exit from the reactors and flow via conduits DC[0042] 1, DC2, DC3, DC4, respectively, to a solids receptacle 216 which, optionally, has a filter 217 for filtering the cuttings. Cuttings may be evacuated from the bottom of the receptacle 216 via a conduit DC5 in which flow is selectively controlled by a valve VC.
Drilled cuttings with contaminants are fed to the extraction vessels from a [0043] tank 218 and pumped with a pump 219 in conduits C1-C5. Extractant fluid exits from the tops of the extraction vessels and flows to a separator 220 which produces extractant that flows in a conduit 221 back to the intensifier 226 for re-use and contaminants that exit via a line 223. Pressure reducing valves Vp and heat exchangers HX reduce the pressure and temperature, respectively, of the extractant before it flows to the separator 220.
Various items in the [0044] system 200 have temperature sensors 1, pressure sensors 2, and/or qualitative sensors 3, each of which is in communication with an electronic apparatus 222 (connections shown by dotted lines in FIG. 3). Any, some, or all electronic devices and/or apparatuses in the system 200 can be cooled as items are cooled in the systems of FIGS. 1 and 2. As shown in FIG. 3, extractant fluid from the extraction vessels is introduced to a pressure reducing apparatus 230 which produces a flow of cooled fluid and provides cooled fluid to a cooling apparatus 225 around or near one of the temperature sensors 1 and/or to a cooling apparatus 224 (via lines 231, 232) around or near the electronic apparatus 222 (via lines 223, 234).
PCT Application PCT/US02/02817 (Int'l Publication No. WO 02/064233 A1, published Aug. 22, 2002, incorporated fully herein for all purposes) discloses processes for cleaning of hydrocarbon-containing materials with critical and supercritical solvents. The disclosed systems are amenable to computer control using standard computer control systems. It is within the scope of the present invention to provide cooling of these standard computer control systems and to provide cooling of electronic devices used in these processes. For example, and not by way of limitation, FIG. 4 shows a [0045] process 800 according to the present invention (which is like a process in FIG. 8B of PCT/US02/02817) which provides for cooling of electronic device(s) E (shown schematically in FIG. 4) which can be any electronic device disclosed herein for monitoring and/or controlling any function, device, equipment or apparatus in the process 800. A pressure-reducing apparatus P (any disclosed herein) receives fluid in a line L from a line 820 and produces a cooling effect. The electronic device (or devices) E are in heat exchange relation with heat exchanger apparatus H which maintains the temperature around the device(s) E (optionally with an enclosure N) within a preferred temperature operation range. Fluid returns back to the line 820 from the heat exchanger apparatus H. A dotted line D indicates connection of the device(s) E to a control system S of a compressor 816, but it is within the scope of this invention for there to be device(s) E associated with any device or apparatus of the system 802 and for such device(s) to be cooled as described herein. Similar cooling apparatus may be used with any process, equipment, apparatus, etc. of PCT/US02/02817.
The [0046] system 800 may be used to clean and/or desulfurize liquids with solids therein, such as used motor oils or fuels. A system such as the system 802 may be used to clean any fluid or material contaminated as described herein. The system 802 includes a reservoir 804 containing the material-to-be-treated 806, a pump 808 (or any suitable material transfer device), and a feed line 810. The system 800 also includes an extracting fluid supply system 812 which includes a reservoir 814 containing extraction fluid 815, the compressor 816, an feed line 818 and a recycle line 820. The system 802 is a multi-staged system having four extractors 822 a-d in series and a separator 824. Each extractor 822 includes a membrane 826 separating each extractor 822 into an upper section 828 and a lower section 830. The membranes 826 allow water and polar compounds to migrate from the upper sections 828 into the lower sections of each extractor. The first extractor 822 a is connected to the feed line 810, while the other three extractors 822 b-d include a forwarding line 832, which feeds the extractors 822 b-d with the contents of the upper section 828 of the preceding extractor 822 a-c, i.e., the contents of the upper section 828 of the extractor 822 a is the feed for the extractor 822 b via forwarding line 832 and so on. Finally, the contents of the upper section 828 of the extractor 822 d are forwarded to the separator 824 via a separator feed line 832. Each extractor 822 also includes an extractor feed line 836 connected to the feed line 818. Each feed line 836 may include a separate flow controlling valve 838, where the valves 838 allow the amount of extraction fluid 815 entering each extractor 822 a-d to be separately controlled so that the amount of extraction fluid 815 being supplied to each extractor 822 a-d can be different. Each extractor 822 a-d also includes an aqueous phase outlet 840 connected to a waste aqueous storage system 842 via waste lines 844. The storage system 842 includes a pressure reduction valve 846 and a heat exchanger 848 to reduce the pressure to ambient pressure and allow the temperature to warm to room temperature and a waste water storage container 850. The waste water can be forwarded to a water treatment facility for further processing. The separator 824 includes a finished product outlet 852 and an extraction fluid outlet 854. The finished product outlet 852 is connected to a finished product storage system 856 via finished product line 858. The finished product storage system 856 includes a pressure reduction valve 860 and a heat exchanger 862 to reduce the pressure to ambient pressure and allow the temperature to warm to room temperature and a finished product storage container 864. The extraction fluid outlet 854 is connected to the recycle line 820 passing through a pressure reduction valve 866 and a heat exchanger 868 to reduce the pressure to ambient pressure and allow the temperature to warm to room temperature prior to mixing with the fresh extraction fluid going into the compressor 816. The extraction fluid may be any extraction fluid disclosed herein.
The present invention, therefore, provides a process for cleaning a material with a cleaning system having system apparatus and at least one electronic device associated with the system apparatus, the at least one electronic device having a specified temperature operation range, the system having contacting apparatus, the process including contacting a material with an extracting fluid under conditions of temperature and pressure sufficient to maintain the extracting fluid at, near or above its critical point to produce a clean material, flowing the extracting fluid from the contacting apparatus to pressure reducing apparatus to lower pressure of the extracting fluid, lowering the pressure of the extracting fluid with the pressure reducing apparatus, thereby cooling the extracting fluid producing cooled extracting fluid, and flowing the cooled extracting fluid in heat exchange relation with the at least one electronic device to maintain temperature of the at least one electronic device within the specified temperature operation range. Such a process may include one or some (in any possible combination) of the following: wherein the extracting fluid is selected from the group consisting of Xe, HN[0047] ₃, lower aromatics, nitrous oxide, water, CO, CO₂, H₂O, lower alcohols, lower alkanes, lower alkenes and mixtures or combinations thereof; wherein the extracting fluid is CO₂; wherein the material is a drill fluid and the clean material comprises a hydrocarbon product substantially free of contaminants, a solids product substantially free of hydrocarbons and other contaminants, and an aqueous product; wherein the material is a used oil and the clean material comprises a cleaned oil substantially free of water and water soluble contaminants; wherein the material is a hydrocarbon fuel and the clean material comprises a cleaned fuel having a lower sulfur content than the hydrocarbon fuel prior to cleaning; wherein the material is a hydrocarbon contaminated soil and the clean material comprises a hydrocarbon product substantially free of solids, water and water soluble contaminants, a cleaned soil substantially free of hydrocarbon and other contaminants, and an aqueous product substantially free of hydrocarbon; and/or contacting a drill fluid with an extracting fluid under conditions of temperature and pressure sufficient to maintain the extracting fluid at, near or above its critical point to produce a hydrocarbon product substantially free of contaminants, a solids product substantially free of hydrocarbons and other contaminants, and an aqueous product.
The present invention, therefore, provides a cleaned drilling fluid solid which is solid material obtained from a process according to the present invention. [0048]
The present invention, therefore, provides a hydrocarbon composition that is hydrocarbon material and/or drilling additives obtained from a process according to the present invention. [0049]
The present invention, therefore, provides a system for cleaning a material, the system including system apparatus with at least one electronic device associated with the system apparatus, the at least one electronic device having a specified temperature operation range, the system apparatus including contacting apparatus for contacting the material with an extracting fluid to clean the material under conditions of temperature and pressure sufficient to maintain the extracting fluid at, near, or above its critical point, pressure reducing apparatus for receiving extracting fluid from the contacting apparatus and for lowering pressure of the extracting fluid thereby producing cooled extracting fluid, heat exchange apparatus for receiving the cooled extracting fluid, the heat exchange apparatus in heat exchange relation with the at least one electronic device for maintaining temperature of the at least one electronic device within the specified temperature operation range. Such a process may include one or some (in any possible combination) of the following: wherein the pressure reducing apparatus is a pressure reducing valve; wherein the pressure reducing apparatus is a pressure reducing orifice device; wherein the at least one electronic device is within an enclosure; and/or wherein the pressure reducing apparatus is within the same enclosure. [0050]
In conclusion, therefore, it is seen that the present invention and the embodiments disclosed herein and those covered by the appended claims are well adapted to carry out the objectives and obtain the ends set forth. Certain changes can be made in the subject matter without departing from the spirit and the scope of this invention. It is realized that changes are possible within the scope of this invention and it is further intended that each element or step recited in any of the following claims is to be understood as referring to all equivalent elements or steps. The following claims are intended to cover the invention as broadly as legally possible in whatever form it may be utilized. Any patent or patent application referred to herein is incorporated fully herein for all purposes. The invention claimed herein is new and novel in accordance with 35 U.S.C. § 102 and satisfies the conditions for patentability in § 102. The invention claimed herein is not obvious in accordance with 35 U.S.C. § 103 and satisfies the conditions for patentability in § 103. This specification and the claims that follow are in accordance with all of the requirements of 35 U.S.C. § 112. The inventors may rely on the Doctrine of Equivalents to determine and assess the scope of their invention and of the claims that follow as they may pertain to apparatus not materially departing from, but outside of, the literal scope of the invention as set forth in the following claims. All patents referred to herein are incorporated fully herein for all purposes.[0051]

Claims

What is claimed is:

1. A process for cleaning a material with a cleaning system having system apparatus and at least one electronic device associated with the system apparatus, the at least one electronic device having a specified temperature operation range, the system having contacting apparatus, the process comprising

contacting a material with an extracting fluid under conditions of temperature and pressure sufficient to maintain the extracting fluid at, near or above its critical point to produce a clean material,

flowing the extracting fluid from the contacting apparatus to pressure reducing apparatus to lower pressure of the extracting fluid,

lowering the pressure of the extracting fluid with the pressure reducing apparatus, thereby cooling the extracting fluid producing cooled extracting fluid, and

flowing the cooled extracting fluid in heat exchange relation with the at least one electronic device to maintain temperature of the at least one electronic device within the specified temperature operation range.

2. The process of claim 1 wherein the extracting fluid is selected from the group consisting of Xe, HN₃, lower aromatics, nitrous oxide, water, CO, CO₂, H₂O, lower alcohols, lower alkanes, lower alkenes and mixtures or combinations thereof.

3. The process of claim 1 wherein the extracting fluid is CO₂.

4. The process of claim 1 wherein the material is a drill fluid and the clean material comprises a hydrocarbon product substantially free of contaminants, a solids product substantially free of hydrocarbons and other contaminants, and an aqueous product.

5. The process of claim 1 wherein the material is a used oil and the clean material comprises a cleaned oil substantially free of water and water soluble contaminants.

6. The process of claim 1 wherein the material is a hydrocarbon fuel and the clean material comprises a cleaned fuel having a lower sulfur content than the hydrocarbon fuel prior to cleaning.

7. The process of claim 1 wherein the material is a hydrocarbon contaminated soil and the clean material comprises a hydrocarbon product substantially free of solids, water and water soluble contaminants, a cleaned soil substantially free of hydrocarbon and other contaminants, and an aqueous product substantially free of hydrocarbon.

8. The process of claim 1 further comprising

contacting a drill fluid with an extracting fluid under conditions of temperature and pressure sufficient to maintain the extracting fluid at, near or above its critical point to produce a hydrocarbon product substantially free of contaminants, a solids product substantially free of hydrocarbons and other contaminants, and an aqueous product.

9. The process of claim 10 wherein the extracting fluid is CO₂.

10. The process of claim 1 wherein the at least one electronic device is in an enclosure.

11. The process of claim 10 wherein the pressure reducing apparatus is within the enclosure.

12. A cleaned drilling fluid solid comprising a solid material obtained from a process of claim 8.

13. A hydrocarbon composition comprising a hydrocarbon material and drilling additives obtained from a process of claim 8.

14. A system for cleaning a material, the system comprising

system apparatus with at least one electronic device associated with the system apparatus,

the at least one electronic device having a specified temperature operation range,

the system apparatus including contacting apparatus for contacting the material with an extracting fluid to clean the material under conditions of temperature and pressure sufficient to maintain the extracting fluid at, near, or above its critical point,

pressure reducing apparatus for receiving extracting fluid from the contacting apparatus and for lowering pressure of the extracting fluid thereby producing cooled extracting fluid,

heat exchange apparatus for receiving the cooled extracting fluid, the heat exchange apparatus in heat exchange relation with the at least one electronic device for maintaining temperature of the at least one electronic device within the specified temperature operation range.

15. The system of claim 14 wherein the pressure reducing apparatus is a pressure reducing valve.

16. The system of claim 14 wherein the pressure reducing apparatus is a pressure reducing orifice device.

17. The system of claim 14 further comprising

an enclosure, the at least one electronic device within the enclosure.

18. The system of claim 17 further comprising

the pressure reducing apparatus within the enclosure.

19. The system of claim 14 wherein the heat exchange apparatus if from the group consisting of heat sink and tube heat exchangers.

20. Any invention disclosed herein of the inventor named herein.