Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3629551 A
Publication typeGrant
Publication dateDec 21, 1971
Filing dateOct 22, 1969
Priority dateOct 29, 1968
Also published asDE1954458A1, DE1954458B2
Publication numberUS 3629551 A, US 3629551A, US-A-3629551, US3629551 A, US3629551A
InventorsMasao Ando
Original AssigneeChisso Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Controlling heat generation locally in a heat-generating pipe utilizing skin-effect current
US 3629551 A
Abstract  available in
Images(1)
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

United States Patent 1111 3,62

72] Inventor Masao Ando [56) References Cited YoItohIm Jilnn UNITED STATES PATENTS 1211 p 3 1 3 969 1,722,797 7/1929 Jessup 219/300 ux 1 1 1 2,561,249 7/1951 T0mlinson.. 219/300 ux [45] Patented Dec. 21,1971

, 3,293,407 12/1966 Ando 219/301 [73] Asslgnee Chino Corporation 0, FOREIGN PATENTS [32] p i i 0, 29, 1968 1,039,832 8/1966 Great Britain 219/300 1 Primary Examiner-R. F. Staubly 1 43/78735 Attorney-Fred c. Philpitt ALLY [54] CONTROLLING HEAT GENERATlON LOC ABSTRACT: In a heat-generating pipe comprising a fer- IN A HEAT-GENERATING PIPE UTILIZING SK d l d d CURRENT romagnetlc pipe an an insu ate con uctor hne mstalled EFFECT D therethrough wherem an AC flows through concentratediy 1n 6 Chums 3 the inner skin region thereof due to the skin effect of AC heat [52] US. Cl 219/300, quantity generated in the heat generating pipe is low), com 219/307, 338/217 trolled by changing one or more factors of those consisting of [51] InLCI "051) 3/00 cross sectional area of the Conductor line resistivity of the [50] Field of Search 219/300, same inside diameter of the ferromagnetic pipe resistivity of 1"7 I 1 O 1 1 I 1 5 i p the same and permeability of the same.

FIG.

CONTROLLING IIEAT GENERATION LOCALLY IN A HEAT-GENERATING PIPE UTILIZING SKIN-EFFECT CURRENT DESCRIPTION This invention relates to a method for controlling heat generation locally in a heat-generating pipe. More particularly this invention relates to a method for controlling heat generation locally according to the demand of a to-be-heated body, in a heat-generating pipe which utilizes skin-effect current and comprises as a heat-generating body, of a ferromagnetic pipe to which electricity is supplied from one source.

The heat-generating pipes utilizing skin-effect current in which the method of the present invention is applied are those disclosed in U.S. Pat. No. 3,293,407 or U.S. Pat. No. 3,515,837.

The principle of heat-generating pipe utilizing skin-effect current will be more fully described with reference to the attached drawing:

FIG. 1 and FIG. 2 show the constructions and wirings of two heat-generating pipes based upon different principles; and

FIG. 3 is one embodiment of the present invention hereinafter fully explained.

FIG. I shows the construction and wiring of the heatgenerating pipe disclosed in the above-mentioned U.S. Pat. No. 3,293,407. In this figure, l is a ferromagnetic pipe, 2 is an insulated conductor line which enters the ferromagnetic pipe from one end 3 and is connected to the other end 4 after passed therethrough, 5 is a conductor line connected to the above-mentioned one end 3 of the ferromagnetic pipe. The other ends of the above-mentioned conductor lines 2 and 5 are connected to two terminals of an AC source 6. When an AC of a suitable frequency is passed through the circuit thus formed, the AC flowing through the pipe 1 is concentrated in a limited inside surface region (skin region) of the pipe 1 due to skin effect, generating a joules heat corresponding to the electric resistance of the above-mentioned skin region and substantially no electric potential appears on the outside surface of the pipes 1.

FIG. 2 shows a construction of another heat-generating pipe disclosed in U.S. Pat. No. 3,515,837. In this Figure, l and l' are two ferromagnetic pipes. An insulated conductor line 2 is passed through the pipes 1 and l successively as shown in FIG. 2 and both ends of it are connected to different terminals of an AC source 6. The left ends 3 and 3' of the ferromagnetic pipes l and l and the right ends 4 and 4 of the same pipes l and l are connected, respectively, with conductor lines 7 and 7' (e.g., electric wire). When an AC of a suitable frequency is passed through the conductor 2, an AC is induced in the ferromagnetic pipes l and l, and flows through the circuit formed by the ferromagnetic pipes l and 1' and the conductor lines 7 and 7 When the impedances of the conductor lines 7 and 7' are arranged to be substantially zero (which can be realized by shortening the conductor lines 7 and 7 by placing the ends of the pipes 3, 3 and 4, 4' respectively as close as possible, and using the conductor lines 7 and 7 of which the electric resistance is as low as possible), the current flowing through these pipes is concentrated in a limited inside surface region (skin region) of the pipes l and 1' due to skin effect, generating a joules heat corresponding to the electric resistance of the said skin region, and substantially no electric potential appears on the outside surface of the ferromagnetic pipes l and l.

In the above-mentioned two types of heat-generating pipe, the depth or thickness S of the inside surface region of the ferromagnetic pipe in which the AC flows, is expressed by following equation:

V P/l -f wherein p is the resistivity of ferromagnetic material constructing the pipe ((1 cm.), 1. is the permeability of the same material and f is the frequency of AC (Hz.

If there are relations expressed by formulas l d among the thickness t (cm.) of the ferromagnetic pipe used, the inside diameter d (cm.) of the pipe, the length I (cm.) of the pipe and the depth or thickness s mentioned above, substantially no electric potential appears on the outside surface of the ferromagnetic pipes. Even if two arbitrary points of the surface of these ferromagnetic pipes are connected by a conductor line 8 as in FIGS. l and 2, no current flows in this conductor. Further a substance can be directly contacted with the surface of such ferromagnetic pipes, without any leakage of current from the ferromagnetic pipes. Accordingly, when the heat-generating pipe of this kind is used to heat a substance, it is possible to contact the substance.

If a depth s of a surface skin in the equation I is to be illustrated by a concrete example, it is only 0.] cm. in the case where a commercial steel pipe is used as a ferromagnetic pipe and the frequency of a current supplied to a heat-generating pipe is 50 or 60 Hz. Accordingly, a steel pipe having a thickness of more than 0.2 cm. can be used as the ferromagnetic pipe of a heat-generating pipe of this kind and there is no need of special precaution to the material of heat-generating pipes and current to be supplied.

Although the heat-generating pipes having constructions shown in FIGS. 1 and 2 are those applied to single-phase circuits, the application of these heat-generating pipes to threephase circuits will be easy for a person having an ordinary skill in the art.

The amount of heat generated (W watt) per cm. of the above-mentioned heat-generating pipe can be calculated as follows: A. The amount of heat generated in the ferromagnetic pipe (W watt); The resistance R, (ohm/cm.) of a ferromagnetic pipe will be approximately expressed from the equation I by the equation of If the amount of current flowing is i ampere, the amount of heat will be expressed by the equation of W,=i R1%i ;J/5,03O1rd (4) B. The amount of heat generated iri the Filafed conductor line W watt); if the resistance per cm. of a conductor line is R (ohm/cm), the amount of heat will be expressed by W FR, (5) The heat generated in the insulated conductor line is con ducted mainly by a medium between the conductor line and the ferromagnetic pipe. Such a medium is usually air but a better heat conductor such as water, oils and other liquid madium may be used. The use of such a liquid medium renders the allowable current of the conductor line about three times as large as that of gaseous medium, e.g., air. Thence the use of liquid medium is economical particularly in case of high-capacity heat-generating pipe.

Thus the amount of heat generated per cm. of this kind of heat-generating pipe (W watt) is the sum of the amounts of heat generation expressed by the above-mentioned equations 4 and 5.

r z (6) and approximately Imp f-5,03o1rd The above-mentioned heat-generating pipe utilizing skin effect current can be made to extend as long as several kilometers by supplying electricity from only one point if the electric potential of an electricity source which supplies electricity to it is elevated. This is one of the notable advantages of the heatgenerating pipe of this kind. When one heat-generating pipe of such a long length is installed with bends in order to use it in the heating of surfaces of constructions such as floors of buildings, wall surfaces or road surfaces, it is possible to some extent to change locally the amount of heat to be supplied to a to-be-heated surface by adjusting the density of heat-generating pipes installed per unit area of to-be-heated surface. On the contrary, it is impossible to adjust locally the amount of heat to be supplied, as it is, in the temperature maintenance and heating of such a linear construction as a pipeline.

In general, when a long pipeline is installed, the environment around the installed pipelines is not uniform. There will be changes in whether sunshine is large or small, whether the pipeline is above or under the ground or whether it is in water or not and heat loss from the pipeline varies depending upon each environment. Further there may be a case where a part of the transporting material is separated into a different streamline or a different streamline is introduced in the course of a pipeline, causing a local change of the amount of flow and hence a local change in the amount of heat to be supplied. When a pipeline is designed based upon the maximum amount of heat to be supplied, the amount of heat generation in a part where lesser amount of heat is required becomes excessive, which is not desirable because the transported fluid is overheated. It is possible to avoid such excessive heat generation by dividing a heat-generating pipe into various sections and supplying respectively, electric potentials suitable to each section. However, such a method is not preferable because it makes the unified control of a heat-generating pipe impossible and diminishes the above-mentioned notable advantage of the heat-generating pipe of this kind.

Accordingly, it is an object of the present invention to provide a method for solving the problem relating to the drawback of the heat-generating pipe of this kind.

Such an object can be attained by the method of the present invention which is characterized by changing one or more factors of those consisting of the cross-sectional area of the conductor line, the resistivity of the same, the resistivity of ferromagnetic pipe, the permeability of the same and inside diameter of the same to locally control heat quantity generated in a heat-generating pipe utilizing skin-effect current and consisting of a ferromagnetic pipe and an insulated conductor line installed therethrough wherein an AC flows through concentratedly only in the inner skin region thereof, and the strength and frequency of electric current flowing through the insulated conductor line and the heat-generating pipe are constant.

As expressed approximately in the above-mentioned equation 6, the amount of heat generation per unit length of this kind of heat-generating pipe is the sum of the heat generated in the inside skin region of the ferromagnetic pipe,W,: 'i M 50301rd and that generated in the insulated conductor line, W,=i R,. Among the factors having influence on the abovementioned heat generation, current i and frequency f of AC are constant in each part of the heat-generating pipe and cannot be changed, but l resistivity p and (2) permeability p. of a ferromagnetic pipe can be changed by changing the material of the ferromagnetic pipe, (3) diameter of a ferromagnetic pipe can be selected arbitrarily even when the pipe is of the same material and (4) resistivity (R of an insulated conductor line can be varied by arbitrarily selecting a material and/or diameter of the conductor line. In general it is convenient to construct a heat-generating pipe utilizing skin-effect current and having a wide range of variation of heat-generating amount per unit length using a steel pipe and a copper wire most easily available in the market and changing the inside diameter of the steel pipe and/or the cross-sectional area of the insulated conductor line.

One embodiment of the present invention can be explained by referring to FIG. 3. In this drawing, 9 is a fluid-transporting pipe one portion of which is installed above the ground and another portion of which is installed underground. 10 shows soil and sand. The portion installed in .the underground requires a lesser amount of heat compared with the portion exposed to the air in order to maintain the temperature. In some cases, it is possible to minimize the change of the fluid temperature in a transportation pipe even with a constant supply of heat per unit length by using, as a relatively good lagging layer ll for the underground portion, and an insulating material of either reduced efficiency or reduced thickness for the portion above the ground. However, it is desirable in general to minimize the regulation of the fluid temperature by minimizing the heat loss as low as possible. Particularly, in a long distance pipeline, the latter is economical and reasonable.

In FIG. 3, l and l are ferromagnetic pipes installed in a transportation pipe 9. At a junction point 12, they are connected by welding. 2 and 2' are conductor lines passing through the ferromagnetic pipes l, l. The one end of the conductor line 2 is connected to one terminal of AC source 6 as indicated by a broken line, and the other end of which is connected to a conductor line 2' through the junction point 13, and the conductor line 2' is connected to one end of ferromagnetic pipe 4 after passing through the ferromagnetic pipe 1'. On the other hand, one end 3 of the ferromagnetic pipe 1 is connected to the other terminal of AC source 6 by a conductor line 5 as indicated by a broken line and thus a heatgenerating pipe is constructed. 14 is a connection. box attached to the heat-generating pipe. lf kinds of insulated conductor lines are changed in one heat-generating pipe as in this example or if a heat-generating pipe is long or has many bends, the connection box is convenient for the construction and management of the heat-generating pipe.

ln applying the method of the present invention to the case illustrated in FIG. 3, a material having a greater resistivity and/or permeability than that for the pipe 1' lying in the underground may be used for a ferromagnetic pipe I of a heatgenerating pipe lying above the ground, or if the same material is used, the diameter of the pipe 1' may be reduced, or the material or cross-sectional area of each insulated conductor line is selected in such a way that the resistance of the line 2 is greater than that of the line 2'.

Since the heat quantity W,, Le, iR generated in the insulated conductor line is exceedingly small compared with the heat quantity W, generated in the ferromagnetic pipe, among the total heat quantity W of this kind of heat-generating pipe which can be expressed by a formula 6 or 7, it is not so effective to make changes in the insulated conductor line in order to change the heat generation of the heat-generating pipe.

Commercial steel pipes are useful for the ferromagnetic pipes of the heat-generating pipe of this kind, because it is inexpensive and available from market in various sizes. Accordingly, it is most convenient and effective to use steel pipes in the practice of the present invention and change locally their inside diameter according to the demand of local control of heat generation. For example, in FIG. 3, such an arrangement will be sufficient that a steel pipe 1 having a relatively small inside diameter is used in order to increase heat generation based upon the equation 4 in the heating of the portion lying above the ground where the heat loss is relatively large and a steel pipe 1 having a greater inside diameter than that of l is used as a heating pipe for the portion lying underground. The selection of the diameter of ferromagnetic pipe can be made easily by the calculation based upon a required temperature and heat loss using an equation 3.

The foregoing description is oflered to illustrate a preferable embodiment of the present invention and not to limit the material of ferromagnetic pipe constituting a heat-generating pipe only to a steel pipe in the method of the present invention.

Further, the foregoing description is almost exclusively directed to the case of application in pipe lines but the method of the present invention can be also applied widely and effectively to the heating for temperature maintenance, prevention of freezing or melting of snow for walls of constructions, floors, rooves, road surfaces runways for aircraft, surface grounds of rail ways or tracks, bridges and power transmission lines, and to the heating or temperature maintenance of tanks wherein temperature reduction is undesirable.

What is claimed is:

l. in the known type of heat-generating apparatus comprising a length of ferromagnetic pipe, a first length of an electrical conductor line disposed within said ferromagnetic pipe but insulated therefrom, and electrical and power connections such that upon the passage of alternating voltage through said first length of electrical conductor line there is a concentrated flow of current along the inner skin of the ferromagnetic pipe to thereby generate heat in said ferromagnetic pipe, the improvement which comprises:

a. said ferromagnetic pipe being composed of at least two segments of differing heat-generating capacity,

b. the heat-generating ability of each of said segments of pipe being governed by primary heat-generating factors which include 1. the cross-sectional area of the conductor line,

2. the resistivity of the conductor line,

3. the resistivity of the ferromagnetic pipe,

4. the permeability of the ferromagnetic pipe, and 5. the inside diameter of the ferromagnetic pipe,

c. at least one of the segments of said ferromagnetic pipe being constructed so that it has at least one of the aforesaid heat-generating factors which is different from the corresponding heat-generating factor of another segment of the ferromagnetic pipe.

2. In the known type of heat-generating apparatus comprising a length of ferromagnetic pipe, a first length of an electrical conductor line disposed within said ferromagnetic pipe but insulated therefrom, and electrical and power connections such that upon the passage of alternating voltage through said first length of electrical conductor line there is a concentrated flow of current along the inner skin of the ferromagnetic pipe to thereby generate heat in said ferromagnetic pipe, the improvement which comprises said ferromagnetic pipe having at least one segment wherein the cross-sectional area of the conductor line passing therethrough differs from that of at least one other segment of the ferromagnetic pipe.

3. In the known type of heat-generating apparatus comprising a length offerromagnetic pipe, a first length of an electrical conductor line disposed within said ferromagnetic pipe but insulated therefrom, and electrical and power connections such that upon the passage of alternating voltage through said first length of electrical conductor line there is a concentrated flow of current along the inner skin of the ferromagnetic pipe to thereby generate heat in said ferromagnetic pipe, the improvement which comprises said ferromagnetic pipe having at least one segment wherein the resistivity of the conductor line passing therethrough differs from that of at least one other segment of the ferromagnetic pipe.

4. In the known type of heat-generating apparatus comprising a length of ferromagnetic pip'e, a first length of an electrical conductor line disposed within said ferromagnetic pipe but insulated therefrom, and electrical and power connections such that upon the passage of alternating voltage through said first length of electrical conductor line there is a concentrated flow of current along the inner skin of the ferromagnetic pipe to thereby generate heat in said ferromagnetic pipe, the improvement which comprises said ferromagnetic pipe having at least one segment wherein the resistivity of the ferromagnetic pipe difiers from that of at least one other segment of ferromagnetic pipe.

5. In the known type of heat-generating apparatus comprising a length of ferromagnetic pipe, a first length of an electrical conductor line disposed within said ferromagnetic pipe but insulated therefrom, and electrical and power connections such that upon the passage of alternating voltage through said first length of electrical conductor line there is a concentrated flow of current along the inner skin of the ferromagnetic pipe to thereby generate heat in said ferromagnetic pipe, improvement which comprises said ferromagnetic pipe having at least one segment wherein the permeability of the ferromagnetic pipe differs from that of at least one other segment of the ferromagnetic pipe.

6. In the known type of heat-generating apparatus comprising a length of ferromagnetic pipe, a first length of an electrical conductor line disposed within said ferromagnetic pipe but insulated therefrom, and electrical and power connections such that upon the passage of alternating voltage through said first length of electrical conductor line there is a concentrated flow of current along the i nner skin of the ferromagnetic pipe to thereby generate heat in said ferromagnetic pipe, the improvement which comprises said ferromagnetic pipe having at least one segment wherein the inside diameter of the ferromagnetic pipe differs from that of at least one other segment of the ferromagnetic pipe.

Disclaimer 3,629,551.Mas0a Ando, Yokohamashi, Japan. CONTROLLING HEAT GENERATION LOCALLY IN A HEAT-GENERATING PIPE UTILIZING SKIN-EFFECT CURRENT. Patent dated Dec. 21, 1971. Disclaimer filed June 22, 1971, by the assignee, Chz'sso Gowpomtz'on.

Hereby disclaims the portion of the term of the patent subsequent to Dec. 20, 1983.

[Oyficial Gazette September 12, 1972] Disclaimer 3,629,55L-Masoa Ando, Yokohamashi, Japan. CONTROLLING HEAT GENERATION LOCALLY IN A HEAT-GENERATING PIPE UTILIZING SKIN-EFFECT CURRENT. Patent dated Dec. 21, 1971. Disclaimer filed June 22, 1971, by the assignee, O/zz'sso Corporation.

Hereby disclaims the portion of the term of the patent subsequent to Dec. 20, 1983.

[Oyfioz'al Gazette September 12,1972]

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1722797 *Nov 10, 1925Jul 30, 1929Western Electric CoMethod of and apparatus for applying and baking an insulating enamel coating
US2561249 *Feb 7, 1949Jul 17, 1951Edward R TomlinsonHeater for oil well tubing
US3293407 *Nov 7, 1963Dec 20, 1966Chisso CorpApparatus for maintaining liquid being transported in a pipe line at an elevated temperature
GB1039832A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3983360 *Nov 27, 1974Sep 28, 1976Chevron Research CompanyMeans for sectionally increasing the heat output in a heat-generating pipe
US4110599 *Feb 5, 1976Aug 29, 1978Chevron Research CompanyMethod and means for decreasing the heat output of a segment of a heat generating pipe
US4132884 *Feb 14, 1978Jan 2, 1979Chevron Research CompanyMethod and means for segmentally reducing heat output in a heat-tracing pipe
US4142093 *Feb 14, 1978Feb 27, 1979Chevron Research CompanyMethod and means for segmentally reducing heat output in a heat-tracing pipe
US4408117 *May 28, 1980Oct 4, 1983Yurkanin Robert MImpedance heating system with skin effect particularly for railroad tank cars
US4456186 *Mar 9, 1981Jun 26, 1984Chisso Engineering Co. Ltd.Electrically heated reactor for high temperature and pressure chemical reactions
US5182792 *Aug 28, 1991Jan 26, 1993Petroleo Brasileiro S.A. - PetrobrasProcess of electric pipeline heating utilizing heating elements inserted in pipelines
US6592288Oct 18, 2001Jul 15, 2003Joong H. ChunHigh-traction anti-icing roadway cover system
US7644765Oct 19, 2007Jan 12, 2010Shell Oil CompanyHeating tar sands formations while controlling pressure
US7673681Oct 19, 2007Mar 9, 2010Shell Oil CompanyTreating tar sands formations with karsted zones
US7673786Apr 20, 2007Mar 9, 2010Shell Oil CompanyWelding shield for coupling heaters
US7677310Oct 19, 2007Mar 16, 2010Shell Oil CompanyCreating and maintaining a gas cap in tar sands formations
US7677314Oct 19, 2007Mar 16, 2010Shell Oil CompanyMethod of condensing vaporized water in situ to treat tar sands formations
US7681647Mar 23, 2010Shell Oil CompanyMethod of producing drive fluid in situ in tar sands formations
US7683296Mar 23, 2010Shell Oil CompanyAdjusting alloy compositions for selected properties in temperature limited heaters
US7703513Oct 19, 2007Apr 27, 2010Shell Oil CompanyWax barrier for use with in situ processes for treating formations
US7717171Oct 19, 2007May 18, 2010Shell Oil CompanyMoving hydrocarbons through portions of tar sands formations with a fluid
US7730945Oct 19, 2007Jun 8, 2010Shell Oil CompanyUsing geothermal energy to heat a portion of a formation for an in situ heat treatment process
US7730946Oct 19, 2007Jun 8, 2010Shell Oil CompanyTreating tar sands formations with dolomite
US7730947Oct 19, 2007Jun 8, 2010Shell Oil CompanyCreating fluid injectivity in tar sands formations
US7735935Jun 1, 2007Jun 15, 2010Shell Oil CompanyIn situ thermal processing of an oil shale formation containing carbonate minerals
US7785427Apr 20, 2007Aug 31, 2010Shell Oil CompanyHigh strength alloys
US7793722Apr 20, 2007Sep 14, 2010Shell Oil CompanyNon-ferromagnetic overburden casing
US7798220Apr 18, 2008Sep 21, 2010Shell Oil CompanyIn situ heat treatment of a tar sands formation after drive process treatment
US7798221Sep 21, 2010Shell Oil CompanyIn situ recovery from a hydrocarbon containing formation
US7831133Apr 21, 2006Nov 9, 2010Shell Oil CompanyInsulated conductor temperature limited heater for subsurface heating coupled in a three-phase WYE configuration
US7831134Apr 21, 2006Nov 9, 2010Shell Oil CompanyGrouped exposed metal heaters
US7832484Apr 18, 2008Nov 16, 2010Shell Oil CompanyMolten salt as a heat transfer fluid for heating a subsurface formation
US7841401Oct 19, 2007Nov 30, 2010Shell Oil CompanyGas injection to inhibit migration during an in situ heat treatment process
US7841408Apr 18, 2008Nov 30, 2010Shell Oil CompanyIn situ heat treatment from multiple layers of a tar sands formation
US7841425Nov 30, 2010Shell Oil CompanyDrilling subsurface wellbores with cutting structures
US7845411Dec 7, 2010Shell Oil CompanyIn situ heat treatment process utilizing a closed loop heating system
US7849922Dec 14, 2010Shell Oil CompanyIn situ recovery from residually heated sections in a hydrocarbon containing formation
US7860377Apr 21, 2006Dec 28, 2010Shell Oil CompanySubsurface connection methods for subsurface heaters
US7866385Apr 20, 2007Jan 11, 2011Shell Oil CompanyPower systems utilizing the heat of produced formation fluid
US7866386Oct 13, 2008Jan 11, 2011Shell Oil CompanyIn situ oxidation of subsurface formations
US7866388Jan 11, 2011Shell Oil CompanyHigh temperature methods for forming oxidizer fuel
US7912358Apr 20, 2007Mar 22, 2011Shell Oil CompanyAlternate energy source usage for in situ heat treatment processes
US7931086Apr 18, 2008Apr 26, 2011Shell Oil CompanyHeating systems for heating subsurface formations
US7942197Apr 21, 2006May 17, 2011Shell Oil CompanyMethods and systems for producing fluid from an in situ conversion process
US7942203May 17, 2011Shell Oil CompanyThermal processes for subsurface formations
US7950453Apr 18, 2008May 31, 2011Shell Oil CompanyDownhole burner systems and methods for heating subsurface formations
US7986869Apr 21, 2006Jul 26, 2011Shell Oil CompanyVarying properties along lengths of temperature limited heaters
US8011451Sep 6, 2011Shell Oil CompanyRanging methods for developing wellbores in subsurface formations
US8027571Sep 27, 2011Shell Oil CompanyIn situ conversion process systems utilizing wellbores in at least two regions of a formation
US8042610Oct 25, 2011Shell Oil CompanyParallel heater system for subsurface formations
US8070840Apr 21, 2006Dec 6, 2011Shell Oil CompanyTreatment of gas from an in situ conversion process
US8083813Dec 27, 2011Shell Oil CompanyMethods of producing transportation fuel
US8113272Oct 13, 2008Feb 14, 2012Shell Oil CompanyThree-phase heaters with common overburden sections for heating subsurface formations
US8146661Oct 13, 2008Apr 3, 2012Shell Oil CompanyCryogenic treatment of gas
US8146669Oct 13, 2008Apr 3, 2012Shell Oil CompanyMulti-step heater deployment in a subsurface formation
US8151880Dec 9, 2010Apr 10, 2012Shell Oil CompanyMethods of making transportation fuel
US8151907Apr 10, 2009Apr 10, 2012Shell Oil CompanyDual motor systems and non-rotating sensors for use in developing wellbores in subsurface formations
US8162059Apr 24, 2012Shell Oil CompanyInduction heaters used to heat subsurface formations
US8162405Apr 24, 2012Shell Oil CompanyUsing tunnels for treating subsurface hydrocarbon containing formations
US8172335May 8, 2012Shell Oil CompanyElectrical current flow between tunnels for use in heating subsurface hydrocarbon containing formations
US8177305Apr 10, 2009May 15, 2012Shell Oil CompanyHeater connections in mines and tunnels for use in treating subsurface hydrocarbon containing formations
US8191630Apr 28, 2010Jun 5, 2012Shell Oil CompanyCreating fluid injectivity in tar sands formations
US8192682Apr 26, 2010Jun 5, 2012Shell Oil CompanyHigh strength alloys
US8196658Jun 12, 2012Shell Oil CompanyIrregular spacing of heat sources for treating hydrocarbon containing formations
US8200072Oct 24, 2003Jun 12, 2012Shell Oil CompanyTemperature limited heaters for heating subsurface formations or wellbores
US8220539Jul 17, 2012Shell Oil CompanyControlling hydrogen pressure in self-regulating nuclear reactors used to treat a subsurface formation
US8224163Oct 24, 2003Jul 17, 2012Shell Oil CompanyVariable frequency temperature limited heaters
US8224164 *Oct 24, 2003Jul 17, 2012Shell Oil CompanyInsulated conductor temperature limited heaters
US8224165Jul 17, 2012Shell Oil CompanyTemperature limited heater utilizing non-ferromagnetic conductor
US8225866Jul 21, 2010Jul 24, 2012Shell Oil CompanyIn situ recovery from a hydrocarbon containing formation
US8230927May 16, 2011Jul 31, 2012Shell Oil CompanyMethods and systems for producing fluid from an in situ conversion process
US8233782Jul 31, 2012Shell Oil CompanyGrouped exposed metal heaters
US8238730Aug 7, 2012Shell Oil CompanyHigh voltage temperature limited heaters
US8240774Aug 14, 2012Shell Oil CompanySolution mining and in situ treatment of nahcolite beds
US8256512Oct 9, 2009Sep 4, 2012Shell Oil CompanyMovable heaters for treating subsurface hydrocarbon containing formations
US8257112Sep 4, 2012Shell Oil CompanyPress-fit coupling joint for joining insulated conductors
US8261832Sep 11, 2012Shell Oil CompanyHeating subsurface formations with fluids
US8267170Sep 18, 2012Shell Oil CompanyOffset barrier wells in subsurface formations
US8267185Sep 18, 2012Shell Oil CompanyCirculated heated transfer fluid systems used to treat a subsurface formation
US8272455Sep 25, 2012Shell Oil CompanyMethods for forming wellbores in heated formations
US8276661Oct 2, 2012Shell Oil CompanyHeating subsurface formations by oxidizing fuel on a fuel carrier
US8281861Oct 9, 2012Shell Oil CompanyCirculated heated transfer fluid heating of subsurface hydrocarbon formations
US8327681Dec 11, 2012Shell Oil CompanyWellbore manufacturing processes for in situ heat treatment processes
US8327932Apr 9, 2010Dec 11, 2012Shell Oil CompanyRecovering energy from a subsurface formation
US8353347Oct 9, 2009Jan 15, 2013Shell Oil CompanyDeployment of insulated conductors for treating subsurface formations
US8355623Jan 15, 2013Shell Oil CompanyTemperature limited heaters with high power factors
US8356935Oct 8, 2010Jan 22, 2013Shell Oil CompanyMethods for assessing a temperature in a subsurface formation
US8381815Apr 18, 2008Feb 26, 2013Shell Oil CompanyProduction from multiple zones of a tar sands formation
US8434555Apr 9, 2010May 7, 2013Shell Oil CompanyIrregular pattern treatment of a subsurface formation
US8448707May 28, 2013Shell Oil CompanyNon-conducting heater casings
US8459359Apr 18, 2008Jun 11, 2013Shell Oil CompanyTreating nahcolite containing formations and saline zones
US8485252Jul 11, 2012Jul 16, 2013Shell Oil CompanyIn situ recovery from a hydrocarbon containing formation
US8485256Apr 8, 2011Jul 16, 2013Shell Oil CompanyVariable thickness insulated conductors
US8485847Aug 30, 2012Jul 16, 2013Shell Oil CompanyPress-fit coupling joint for joining insulated conductors
US8502120Apr 8, 2011Aug 6, 2013Shell Oil CompanyInsulating blocks and methods for installation in insulated conductor heaters
US8536497Oct 13, 2008Sep 17, 2013Shell Oil CompanyMethods for forming long subsurface heaters
US8555971May 31, 2012Oct 15, 2013Shell Oil CompanyTreating tar sands formations with dolomite
US8562078Nov 25, 2009Oct 22, 2013Shell Oil CompanyHydrocarbon production from mines and tunnels used in treating subsurface hydrocarbon containing formations
US8579031May 17, 2011Nov 12, 2013Shell Oil CompanyThermal processes for subsurface formations
US8586866Oct 7, 2011Nov 19, 2013Shell Oil CompanyHydroformed splice for insulated conductors
US8586867Oct 7, 2011Nov 19, 2013Shell Oil CompanyEnd termination for three-phase insulated conductors
US8606091Oct 20, 2006Dec 10, 2013Shell Oil CompanySubsurface heaters with low sulfidation rates
US8608249Apr 26, 2010Dec 17, 2013Shell Oil CompanyIn situ thermal processing of an oil shale formation
US8627887Dec 8, 2008Jan 14, 2014Shell Oil CompanyIn situ recovery from a hydrocarbon containing formation
US8631866Apr 8, 2011Jan 21, 2014Shell Oil CompanyLeak detection in circulated fluid systems for heating subsurface formations
US8636323Nov 25, 2009Jan 28, 2014Shell Oil CompanyMines and tunnels for use in treating subsurface hydrocarbon containing formations
US8662175Apr 18, 2008Mar 4, 2014Shell Oil CompanyVarying properties of in situ heat treatment of a tar sands formation based on assessed viscosities
US8701768Apr 8, 2011Apr 22, 2014Shell Oil CompanyMethods for treating hydrocarbon formations
US8701769Apr 8, 2011Apr 22, 2014Shell Oil CompanyMethods for treating hydrocarbon formations based on geology
US8732946Oct 7, 2011May 27, 2014Shell Oil CompanyMechanical compaction of insulator for insulated conductor splices
US8739874Apr 8, 2011Jun 3, 2014Shell Oil CompanyMethods for heating with slots in hydrocarbon formations
US8752904Apr 10, 2009Jun 17, 2014Shell Oil CompanyHeated fluid flow in mines and tunnels used in heating subsurface hydrocarbon containing formations
US8789586Jul 12, 2013Jul 29, 2014Shell Oil CompanyIn situ recovery from a hydrocarbon containing formation
US8791396Apr 18, 2008Jul 29, 2014Shell Oil CompanyFloating insulated conductors for heating subsurface formations
US8816203Oct 8, 2010Aug 26, 2014Shell Oil CompanyCompacted coupling joint for coupling insulated conductors
US8820406Apr 8, 2011Sep 2, 2014Shell Oil CompanyElectrodes for electrical current flow heating of subsurface formations with conductive material in wellbore
US8833453Apr 8, 2011Sep 16, 2014Shell Oil CompanyElectrodes for electrical current flow heating of subsurface formations with tapered copper thickness
US8851170Apr 9, 2010Oct 7, 2014Shell Oil CompanyHeater assisted fluid treatment of a subsurface formation
US8857051Oct 7, 2011Oct 14, 2014Shell Oil CompanySystem and method for coupling lead-in conductor to insulated conductor
US8857506May 24, 2013Oct 14, 2014Shell Oil CompanyAlternate energy source usage methods for in situ heat treatment processes
US8859942Aug 6, 2013Oct 14, 2014Shell Oil CompanyInsulating blocks and methods for installation in insulated conductor heaters
US8881806Oct 9, 2009Nov 11, 2014Shell Oil CompanySystems and methods for treating a subsurface formation with electrical conductors
US8939207Apr 8, 2011Jan 27, 2015Shell Oil CompanyInsulated conductor heaters with semiconductor layers
US8943686Oct 7, 2011Feb 3, 2015Shell Oil CompanyCompaction of electrical insulation for joining insulated conductors
US8967259Apr 8, 2011Mar 3, 2015Shell Oil CompanyHelical winding of insulated conductor heaters for installation
US9016370Apr 6, 2012Apr 28, 2015Shell Oil CompanyPartial solution mining of hydrocarbon containing layers prior to in situ heat treatment
US9022109Jan 21, 2014May 5, 2015Shell Oil CompanyLeak detection in circulated fluid systems for heating subsurface formations
US9022118Oct 9, 2009May 5, 2015Shell Oil CompanyDouble insulated heaters for treating subsurface formations
US9033042Apr 8, 2011May 19, 2015Shell Oil CompanyForming bitumen barriers in subsurface hydrocarbon formations
US9048653Apr 6, 2012Jun 2, 2015Shell Oil CompanySystems for joining insulated conductors
US9051829Oct 9, 2009Jun 9, 2015Shell Oil CompanyPerforated electrical conductors for treating subsurface formations
US9080409Oct 4, 2012Jul 14, 2015Shell Oil CompanyIntegral splice for insulated conductors
US9080917Oct 4, 2012Jul 14, 2015Shell Oil CompanySystem and methods for using dielectric properties of an insulated conductor in a subsurface formation to assess properties of the insulated conductor
US9127523Apr 8, 2011Sep 8, 2015Shell Oil CompanyBarrier methods for use in subsurface hydrocarbon formations
US9127538Apr 8, 2011Sep 8, 2015Shell Oil CompanyMethodologies for treatment of hydrocarbon formations using staged pyrolyzation
US9129728Oct 9, 2009Sep 8, 2015Shell Oil CompanySystems and methods of forming subsurface wellbores
US9181780Apr 18, 2008Nov 10, 2015Shell Oil CompanyControlling and assessing pressure conditions during treatment of tar sands formations
US9226341Oct 4, 2012Dec 29, 2015Shell Oil CompanyForming insulated conductors using a final reduction step after heat treating
US9309755Oct 4, 2012Apr 12, 2016Shell Oil CompanyThermal expansion accommodation for circulated fluid systems used to heat subsurface formations
US9337550Nov 18, 2013May 10, 2016Shell Oil CompanyEnd termination for three-phase insulated conductors
US9399905May 4, 2015Jul 26, 2016Shell Oil CompanyLeak detection in circulated fluid systems for heating subsurface formations
US20040140096 *Oct 24, 2003Jul 22, 2004Sandberg Chester LedlieInsulated conductor temperature limited heaters
US20040177966 *Oct 24, 2003Sep 16, 2004Vinegar Harold J.Conductor-in-conduit temperature limited heaters
US20060137864 *Sep 23, 2003Jun 29, 2006Schmidt + Clemens Gmbh & Co. KgPipe section for a pipe coil
US20070137857 *Apr 21, 2006Jun 21, 2007Vinegar Harold JLow temperature monitoring system for subsurface barriers
US20070209799 *Jan 23, 2007Sep 13, 2007Shell Oil CompanyIn situ recovery from a hydrocarbon containing formation
US20090214196 *Jan 26, 2009Aug 27, 2009Jarle Jansen BremnesHigh efficiency direct electric heating system
US20100147521 *Oct 9, 2009Jun 17, 2010Xueying XiePerforated electrical conductors for treating subsurface formations
US20110124223 *May 26, 2011David Jon TilleyPress-fit coupling joint for joining insulated conductors
US20110124228 *Oct 8, 2010May 26, 2011John Matthew ColesCompacted coupling joint for coupling insulated conductors
US20110132661 *Oct 8, 2010Jun 9, 2011Patrick Silas HarmasonParallelogram coupling joint for coupling insulated conductors
US20110134958 *Oct 8, 2010Jun 9, 2011Dhruv AroraMethods for assessing a temperature in a subsurface formation
WO1984004698A1 *May 25, 1984Dec 6, 1984Metcal IncSelf-regulating porous heater device
WO2003040474A1 *Oct 15, 2002May 15, 2003Chun Joong HHigh-traction anti-icing roadway cover system
Classifications
U.S. Classification392/469, 392/488, 338/217
International ClassificationH05B6/10, F24D13/02
Cooperative ClassificationH05B6/108, F24D13/02, F24D13/024
European ClassificationH05B6/10S6, F24D13/02B2, F24D13/02