JP2000309548A - Gas hydrate production system and production of gas hydrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system for continuously producing methane hydrate on an industrial scale from water and gas containing methane as the major component, e.g. natural gas. SOLUTION: This system for continuously producing methane hydrate has a cylindrical vessel 1, containing water or an antifreezing fluid 5, and equipped with a nozzle 24 to eject a stock gas mixture of steam and gas containing methane as the major component in a given ratio into the water or antifreezing fluid 5, and means 14 to discharge the methane hydrate product 9 out of the vessel 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for producing gas hydrate, and more particularly to an industrial method for producing methane hydrate (or gas hydrate) from a gas mainly containing methane such as natural gas and water. The present invention relates to an apparatus and a method for producing a gas hydrate to be produced in the following manner.

[0002]

2. Description of the Related Art In recent years, natural gas and other gases mainly containing methane have attracted attention as a clean energy source and various constituent materials, and research has been conducted to convert natural gas into a gas hydrate for the purpose of storage or transportation. Has been done. Methane hydrate is composed of water and methane, and its production requires a high pressure of, for example, about 80 MPa or more at a temperature of 303 ° K. And methane hydrate
It is a structurally unstable substance. For example, the water / methane ratio (hydration number) of methane hydrate is determined by the occupancy rate of gas molecules with respect to the structure at the molecular level (theoretically, the hydration number is 1 On the other hand, the water molecule has an apparent hydration number of 5.75) and a water / methane ratio including macro unbound water. Conventionally, methane hydrate is a method in which methane and water are reacted under high pressure and low temperature using a pressure vessel, but this method is only a laboratory method and is manufactured continuously in an industrial manner. There was no known way to do it.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus and a method for industrially and continuously producing methane hydrate from methane-based gas such as water and natural gas. Is to do.

[0004]

Means for Solving the Problems To solve the above problems, the invention claimed in the present application is as follows. (1) A cylindrical container having cooling means, water or antifreeze supplied to the cylindrical container, and
A gas hydrate production apparatus comprising: a nozzle for injecting a raw material gas obtained by mixing a gas containing methane as a main component and steam at a predetermined ratio; and means for discharging methane hydrate generated in the cylindrical container to the outside. . (2) The gas according to (1), wherein the injection nozzle is connected to a pipe to which a mixed gas of a gas containing methane as a main component and steam at a predetermined ratio is supplied, and the pipe has an in-line mixer. Hydrate manufacturing equipment.

(3) The means for discharging produced methane hydrate is a discharge port for water or antifreeze provided on the side of the cylindrical container, and means for drawing the produced methane hydrate to the discharge port ( An apparatus for producing a gas hydrate according to 1) or 2). (4) (1) The apparatus according to any one of (1) to (3), wherein the temperature and pressure of the raw material gas are 200 ° C. or more and 50 atm or more, The mixing ratio is about 1: 4 to 10 by weight, and the reaction temperature and pressure in the cylindrical vessel are 1 to 4 ° C and 20 to 100
A method for producing gas hydrate, comprising synthesizing methane hydrate as an atmospheric pressure.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is an explanatory view showing one embodiment of the methane hydrate production apparatus of the present invention. In FIG. 1, the apparatus includes a cylindrical container 1 having a cooling jacket 3 as a cooling means, water or antifreeze 5 contained in the cylindrical container 1, and water or antifreeze 5 in the cylindrical container. Line 2
3, a nozzle 24 for injecting a raw material gas obtained by mixing a gas containing methane as a main component and steam at a predetermined ratio, and discharging water or antifreeze containing methane hydrate 9 provided on the side of the cylindrical container 1. An outlet 7 and a scraper 14 serving as a means for moving the produced methane hydrate 9 to the outlet 7
Consists of A supply line 4 for water or antifreeze is provided at the bottom of the cylindrical container 1.

[0007] The raw material supply line 23 has a natural gas supply line 25 and a steam supply line 21 as branch pipes.
It has a mixer 22 for further mixing the raw materials mixed at a predetermined ratio supplied from the branch pipe. In addition,
In the figure, 6 is a refrigerant supply line, and 2 is a refrigerant outlet line.

In the apparatus shown in FIG. 1, the cylindrical vessel 1 is composed of a pressure vessel, and the pressure and temperature in the vessel are maintained at the reaction temperature and pressure at which methane hydrate is generated. These temperatures and pressures are usually 1 ° C. to 4 ° C., 2
A range from 0 to 100 atmospheres is preferred. The nozzle 24 may be any nozzle that can uniformly inject high-temperature and high-pressure raw material gas into water or antifreeze. As a specification of the normal nozzle 24, for example, when the pipe diameter for supplying the raw material is 10 mm, a nozzle having a diameter of 0.2 to 2 mm is used. Natural gas and water vapor are mixed in line 25 at a weight ratio of about 1: 4 to 10
And from line 21 and mixed by in-line mixer 22 in line 23 (temperature about 200 ° C.)
From 4, it is injected into the water or antifreeze 5 in the cylindrical container 1. The raw material gas injected from the ejector 24 reacts in water or antifreeze to generate methane hydrate 9, floats on the surface of water or antifreeze, and is sequentially drawn by the scraper 14 in the direction of the discharge port. It is discharged from the outlet 7.

The temperature and pressure in the cylindrical container 1 are controlled to the above-mentioned predetermined values, but these control means are omitted in the figure. The antifreeze may be any antifreeze containing water, such as an antifreeze such as ethylene glycol. The water or antifreeze 5 reduced in the cylindrical container is supplied into the system from the supply line 4 and the liquid level at the outlet 7 is maintained. Hereinafter, specific examples of the present invention will be described.

[0010]

EXAMPLE 1 A natural gas supply line 25 of the apparatus shown in FIG. 1 (capacity of a cylindrical container of 15 liters) was connected to a natural gas cylinder (not shown), and the supply ratio of natural gas and steam was 1: 4. , And supplied from the lines 25 and 21, mixed by the in-line mixer 22, and passed through a pipe 23 to an inner diameter of 1 mm.
These were reacted by spraying into the vessel 1 from the nozzle 24 of, and methane hydrate was continuously produced. Table 1 shows an outline of the production conditions and the results.

[0011]

[Table 1] As shown in Table 1, methane hydrate could be continuously produced in high yield.

[0012]

According to the present invention, methane hydrate can be industrially produced by continuously reacting a gas containing methane as a main component with water or an antifreeze.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a methane hydrate production apparatus of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cylindrical container, 2 ... Refrigerant outlet, 3 ... Cooling jacket, 4
... water or antifreeze supply or discharge line, 5 ... water or antifreeze, 6 ... refrigerant inlet, 7 ... methane hydrate outlet, 9 ... methane hydrate crystal, 14 ... scraper,
21: steam supply line, 22: mixer, 24: nozzle, 25: natural gas supply line.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kenichi Nagata 5-6-4 Tsukiji, Chuo-ku, Tokyo Mitsui Engineering & Shipbuilding Co., Ltd. F-term (reference) 4H006 AA02 AA04 AC93 BC10 BC11 BD81 BD84 BE60

Claims (4)

[Claims] 1. A cylindrical container having a cooling means, water or an antifreeze supplied to the cylindrical container, and a gas mainly composed of methane and steam mixed in the water or the antifreeze at a predetermined ratio. A gas hydrate producing apparatus, comprising: a nozzle for injecting the formed raw material gas; and means for discharging methane hydrate generated in the cylindrical container to the outside. 2. The injection nozzle is connected to a pipe to which a mixed gas of a gas containing methane as a main component and steam at a predetermined ratio is supplied, and the pipe has an in-line mixer. Gas hydrate production equipment. 3. The discharge means for discharging the generated methane hydrate is a discharge port for water or antifreeze provided on a side portion of the cylindrical container, and a means for scraping the generated methane hydrate to the discharge port. 3. The apparatus for producing a gas hydrate according to 1 or 2. 4. The method according to claim 1, wherein the temperature and pressure of the raw material gas are 200 ° C. or more and 50 atm or more, and the mixture of the gas mainly composed of methane and the water vapor in the raw material gas. The ratio is about 1: 4 to 10 by weight,
The reaction temperature and pressure in the cylindrical container are set at 1 to 4 ° C and 20 to 1
A method for producing gas hydrate, comprising synthesizing methane hydrate at 00 atm.