JPS59199993A - Electrode apparatus for electrically heating hydrocarbon underground resources - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrode device for electrically heating hydrocarbon underground resources. This invention relates to an electrode device used for.

In the following description, hydrocarbon underground resources refer to oil sands or tar sands deposited bitumen (BLt).
u, men), and hereinafter referred to as oil unless otherwise specified.

In recent years, with the rise in the price of oil resources, serious consideration is being given to extracting oil from oil sand layers buried underground in countries such as Canada and Venezuela. This oil sand layer normally exists in a layer approximately 1000 meters thick underground, but due to its high viscosity, it cannot be extracted by pumping it up at room temperature.
Conventionally, heated steam was injected into the oil sand layer to raise the temperature of the oil, lowering its viscosity, and then pumping it out. However, this method is inefficient and expensive, so a more productive method is to bury a conduit made of steel or stainless steel pipe that supports the electrode at the bottom end so that the electrode is located in the oil sand layer. Then, connect two such conduits to approximately 3θ. A method was proposed in which the oil sand layer was placed in parallel at a distance of 0 m and a voltage of several hundred to several thousand volts was applied between both electrodes to raise the temperature of the oil sand layer using Joule heat, lowering the viscosity of the oil and extracting the oil. . In this case, since the resistivity of the oil sand layer is several times higher than that of the upper stratum, it is necessary to interpose an insulator between the conduit buried in the stratum and the electrode buried in the oil sand layer. If no insulator is used, current will flow through the strata and no current will flow between the electrodes buried in the oil sand layer. Therefore, there is a rapidly increasing demand for developing insulators that can withstand use under such special conditions.

Therefore, the characteristics that the above insulator must have are: (A) withstand voltage characteristics of several hundred to several thousand volts not only at room temperature but also at temperatures of approximately 300°C, which can reduce the viscosity of oil in the oil sand layer; It has a volume resistivity of at least 1()'Ω-F.

(B) The water contained in the oil sand layer is heated to a temperature of about 3θ0°C which lowers the viscosity of the oil sand layer, so it can withstand hot water of about 3θ0°C.

(C) Mechanical strength that allows the electrode to be suspended, and an oil tank (D) that allows the electrode suspended at the tip of the conduit to be passed through the buried hole.
Approximately 70% due to being buried at a depth of 00m underground
to withstand the pressure of ~.

etc. are required.

This invention was made in view of the above circumstances, and aims to provide an electrode device for electric heating of hydrocarbon underground resources, which has an insulator with excellent voltage resistance, hot water resistance, and mechanical strength. It is something.

This invention will be described in detail below.

As a result of extensive research to develop an insulator that has all of the characteristics described above (~~(D)), the present inventors have developed a cylindrical conduit, which has the same inner diameter as the conduit and an outer diameter that is the same as that of the conduit. A coupling having a large diameter cylindrical part larger than the outer diameter of the conduit and having a tapered screw at the lower end for connecting an electrode and having a large diameter cylindrical part larger than the outer diameter of the conduit at the upper end 1, and a conduit inside the large diameter cylindrical part of this coupling. A bonding insulator made of a glass mica plastic body that firmly connects the lower end of the conduit and a creeping insulator made of a composite material of polyetheretherketone resin and glass fiber formed on the outer surface of the conduit and the coupling. , (A) above
It was discovered that an electrode device for electric heating of hydrocarbon underground resources having all of the characteristics of (D) can be obtained, and this invention was completed.

Examples of the polyetheretherketone resin used in the present invention include aromatic polyetheretherketones developed by British Inverial Chemical Industries Ltd., which have the following chemical structural formula.

As the composite material of polyetheretherketone resin and glass fiber, a composite material having a glass content of 30 to 7θ weight % is used. In the case of composite materials with a glass content of less than 30% by weight, due to the difference in expansion coefficient of the creeping insulator and the metal conduit,
A large stress is generated at the interface between the creeping insulator and the metal conduit and inside the creeping insulator, and the mechanical properties of the creeping insulator are deteriorated.

In the case of a composite material with a glass content of more than 7 (2% by weight), there is no water-blocking property and the electrical properties as a creeping insulator are degraded.

As the metal conduit, a steel pipe or a stainless steel pipe, which has excellent corrosion resistance and excellent strength at high temperatures, is suitable.

Glass mica plastic is an insulation product made from a mixture of glass powder and mica powder, heated to a temperature where the glass softens and flows under pressure, and then pressure-molded in the heated state. It is a thing (details are in the patent application 1973-
siist issue).

Next, an embodiment of the invention shown in the drawings will be described.

In the figure, the lower end of a cylindrical conduit made of a metal material such as steel or stainless steel is fixedly connected to a cylindrical coupling 30 with a coupling insulator made of glass mica plastic. . The inner diameter of the coupling 3 is equal to the inner diameter of the conduit l, and an electrode (not shown) is provided at its lower end.
A tapered screw 3b is formed for connecting the two.

It is electrically insulated by a combined insulator.

Furthermore, a creeping insulator made of polyetheretherketone resin and glass fiber is formed on the outer surface of the coupling 3 and the conduit. If there is no creeping insulator, the creeping insulation distance between the coupling 3 and the conduit is short, and the electrical characteristics of the electrode device are degraded.

Next, the manufacturing process of the above insulator will be explained.

First, the coupling 3 and the conduit 1 are manufactured by patent application Sho 5S-2//
They are bonded using a bonding insulator made of a glass mica plastic body by the method described in No. Jt/. Next, a prepreg tube made of polyetheretherketone resin and glass fiber with a glass content of 30 to 70% by weight is wrapped around the outer surface of the coupling 3 and the conduit, and the outer peripheral surface is held down with a mold to form a 3Sθ~yso Heat and pressure molding is performed at a temperature of ℃ and a pressure of /θ~lθO~, and the glass content is 30~70%.
A creeping insulation material made of a composite material of polyetheretherketone resin and glass fiber is formed.

The insulator of the electrode device of the present invention having the above structure has good electrical and mechanical properties not only at room temperature but also after a hot water test in hot water at 3oθ°C for an SOθ time. This is suitable as a heating electrode device used for extracting underground hydrocarbon resources.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view of one embodiment of the invention. /... conduit, co... joint insulator made of glass mica plastic body, 3... coupling, 3a... large diameter cylindrical part, 3b...
Tapered screw, G... A creeping insulator made of a composite material of polyetheretherketone resin and glass fiber. Agent Masuo Oiwa 1 [4, 3, 3b

Claims (1)

[Claims] A cylindrical coupling having a cylindrical conduit, a large-diameter cylindrical portion having an inner diameter equal to the inner diameter of the conduit, and a large diameter cylindrical portion having an upper end larger than the outer diameter of the conduit, and a tapered thread for connecting an electrode to the lower end. a bonding insulator made of glass mica plastic interposed between the inner wall of the large-diameter cylindrical portion and the lower end of the conduit; and a bonding insulator made of a glass-mica plastic material and coated on the outer surfaces of the conduit and the coupling and made of polyetheretherketone resin and glass. An electrode device for electric heating of hydrocarbon underground resources, characterized by comprising a creeping insulator made of a composite material of fibers.