JP4820678B2 - Roller molding equipment for gas hydrate powder - Google Patents

Description

  The present invention relates to a molding apparatus in a gas hydrate powder production apparatus, and more particularly to a molding apparatus for compression molding powdery gas hydrate powder.

  In recent years, natural gas mainly composed of methane, propane or the like has attracted attention as a clean energy source. In order to transport and store such natural gas, it is liquefied to form liquefied natural gas (LNG). However, the transport and storage of gas by this LNG requires an extremely low temperature state (−162 ° C. or less), and therefore, the transport device and the storage device are expensive.

  Therefore, a gas hydrate powder is produced by hydration reaction of the raw material gas and water, and transported while maintaining the temperature (for example, about −20 ° C.) at which the gas hydrate powder exhibits self-storability, It has also been proposed to store.

  The gas hydrate powder is produced by bringing natural gas or the like into contact with water under a predetermined pressure and temperature condition (for example, 4 to 6 MPa, 0 to 5 ° C.). It is in the form of shaved ice.

  By the way, since such a powdery gas hydrate powder has a small filling rate (volume of gas hydrate powder / volume of container) in the storage tank, a tank or the like having a large volume is required for transportation or storage. Not only is necessary, but also has a problem that the surface area becomes large because it is in the form of powder, and the decomposition rate of decomposition into natural gas and water is very high. In addition, if a large amount is stored, the lower layer is hardened into a rock shape, which makes it difficult to take out.

  Therefore, the present inventor compresses the powdery gas hydrate powder with a molding device to form a molded product having a substantially spherical shape, and transports or stores the gas hydrate powder molded product. (For example, refer to Patent Document 1).

  As shown in FIG. 3, the molding apparatus F supplies the gas hydrate powder n supplied to the hopper chamber 30 to a pair of molding rollers 33a and 33b having opposing pockets 34 (molding recesses). The gas hydrate powder n filled in the pocket 34 is compressed and molded together with the rotation of 33a and 33b. A screw-type pushing device 31 for filling the pocket 34 with the gas hydrate powder n is disposed in the hopper chamber 30 so as to apply a predetermined pressure in addition to the weight of the gas hydrate powder. Yes.

  By the way, according to the knowledge of the present inventor, according to the molding apparatus F as described above, compression is performed under substantially the production conditions (for example, about 4 to 6 MPa, about 2 to 5 ° C.) of the powder snow-like gas hydrate powder n. It turned out that water exudes from this powder n when it shape | molds. And since this gas hydrate powder n has a specific gravity smaller than that of water, the gas hydrate powder n has the property that the exuded water floats up when it accumulates in the hopper chamber 30, and the amount of exuded water when the molding pressure is increased. It was also found that increases.

  When compression molding is performed with the molding apparatus F using the gas hydrate powder n as a raw material, since the exuded water does not accumulate in the initial stage of operation, the pellet p can be produced smoothly, but in the gap between the rollers 34a and 34b, Since the gas hydrate in the compacted state is filled, the water (squeezed water) squeezed by the rollers 34a and 34b is accumulated in the hopper chamber 30 without being drained from the gap between the rollers 34a and 34b. Go.

  If the operation is continued in such a state, the water level in the hopper chamber 30 will rise, and as a result, buoyancy occurs in the gas hydrate powder, and the gas hydrate powder n pushed by the delivery device 31; The gas hydrate powder n to be levitated stays in the vicinity of the tip of the screw of the device 31 one after another, and this becomes a lump.

  Then, the powder n supplied from the feeding device 31 grows a mass having a substantially wedge-shaped cross section extending in the axial direction of the rollers 6 a and 6 b, and becomes a mass b reaching a certain size, thereby opening the hopper chamber 30. The gas hydrate powder n cannot be supplied to the molding rollers 33a and 33b by acting like a plug in the portion 35 and between the molding rollers 33a and 33b, and the molded product p (pellet) of the gas hydrate powder cannot be manufactured. was there.

  Further, when the molding apparatus F is operated at normal pressure (atmospheric pressure), if the pressing force of the pushing device 31 is increased in order to reliably fill the pocket 34, the powders n adhere to each other in the vicinity of the screw tip. There was a similar problem of creating a lump and acting as a stopcock.

When the mass b is generated in this way, it is necessary to interrupt the operation of the molding apparatus F and remove the mass b of the gas hydrate powder n, and work such as disassembly, assembly and adjustment of the apparatus F must be performed. As a result, the operation efficiency of the gas hydrate powder production apparatus is significantly impaired. In particular, when the molding apparatus F manufactures a gas hydrate powder molded product p under a high-pressure atmosphere (4 to 6 MPa) under substantially the conditions for generating gas hydrate powder, the entire apparatus has a thickness of 200 mm or more. There is a problem that the operation of removing the mass b of the gas hydrate powder is extremely difficult because it is housed in a robust pressure-resistant container, and a molding apparatus for a long time (for example, 24 hours) until the mass b is dissolved. The operation of B was stopped, and finally there was a problem that the production amount of the production apparatus for the gas hydrate powder n as a raw material was extremely reduced or the production had to be stopped.
JP 2002-220353 A

  The present invention has been made in order to solve the above-mentioned problems, and the object of the present invention is to form a roller mold that quickly melts a blocking plug due to a lump of gas hydrate powder itself generated between compression molding rollers. The machine is provided.

In order to achieve the above object, a roller type compression molding apparatus according to the present invention comprises:
1) a raw material gas and water by hydration to produce a powdered gas hydrate powder in the compression molding apparatus for compression molding the gas hydrate powder in Ryakudama shape, the compression molding apparatus, the gas A hopper chamber containing hydrate powder, a pair of compression rollers disposed below the opening of the hopper chamber, and a pushing device for supplying gas hydrate powder in the hopper chamber to the compression roller , and The hot water or the cold water is supplied to the pair of compression rollers from the lower part of at least one surface of the hopper chamber, and is drained from the lower part of the other surface.
2) A jet nozzle for hot water or cold water is provided at the lower part of at least one surface of the hopper chamber .

  In the molding apparatus according to the present invention, the mass (occlusion plug) of the substantially wedge-shaped gas hydrate powder generated between the compression molding rollers is directly melted with warm water, so that the melting speed is high. Therefore, the production interruption time of pellets due to clogging of the molding equipment is shortened, and the operation for releasing clogging is particularly improved when producing pellets at high pressures under the conditions under which gas hydrate powder is substantially produced. Prevent the amount from decreasing.

  Furthermore, since the hot water is ejected, the hot water collides with the lump intensively at a high pressure, so that the lump can be melted more efficiently.

Hereinafter, an embodiment of a compression molding apparatus A according to the present invention with reference to FIGS.
As shown in FIGS. 1 and 2, a compression molding apparatus A according to the present invention includes a hopper chamber 5 for storing a gas hydrate powder n and a pair of compression rollers disposed below an opening 5a of the hopper chamber 5. 6a, 6b and a pushing device 12 for supplying the gas hydrate powder n in the hopper chamber 5 to the compression rollers 6a, 6b. The hopper chamber 5 faces the side surfaces of the compression rollers 6a, 6b. Side plates 1a and 1b, and feeder bases 10a and 10b which are formed so as to be inclined toward the gap between the compression roller 6a and the compression roller 6b. A screw type pushing device 12 for supplying the gas hydrate powder n to the compression rollers 6a and 6b is arranged.

  The hot water h1 is supplied from the lower part of the side plate 1a of the hopper chamber 5 to the pair of compression rollers 6a and 6b and drained from the lower part of the other side plate 1b. Furthermore, the nozzle 3 which ejects the said warm water is provided in the lower part of the said side plate 1a.

The warm water h1 is a temperature control of the water squeezed h3 of the gas hydrate powder n discharged from the drain pipe 4, unreacted water in the gas hydrate powder production apparatus, or water such as ion exchange water or pure water. device and transfer pump and reservoir tank and a thermostat consisting of the heat exchanger (not shown) at a predetermined temperature (for example, a range of 60-80 ° C.) are adapted to hold the, through the heat medium pipe 2 The hot water supplied to the hopper chamber 5 and the supplied hot water h <b> 3 are returned to the constant temperature bath via the drain pipe 4.

  In some cases, cooling water (for example, pure water of about 1 ° C.) is circulated through the heat medium pipe 2 of the side plate 1a to cool the side plate 1a and the rollers 6a and 6b.

The gas hydrate powder forming apparatus A for gas hydrate powder n configured in this manner is supplied from a gas hydrate powder production apparatus (not shown) under substantially the conditions for producing gas hydrate powder (for example, about 5 MPa, about 3 ° C.). The gas hydrate powder n is temporarily held in the hopper chamber 5 and supplied to a pair of compression rollers 6a and 6b disposed under the opening 5a of the hopper chamber 5 by the action of the screw-type pushing device 12. the compression roller 6a, is the gas hydrate powder n is reliably filled into the pocket 7 formed in 6b, the compression roller 6a, is compressed in a pellet p with rotation of 6b is fabricated.

In the compressed portion by the compression rollers 6a and 6b, moisture (unreacted water) in the gas hydrate powder n is squeezed out and oozed out. The squeezed water h3 is not drained to the outside through the gap between the molding gaps of the rollers 6a and 6b, and is not discharged to the outside, but via the drain pipe 4 provided at the lower part of the side plate 1b of the hopper chamber 5. Always drained.

  By the way, when the pellets p are manufactured using the apparatus A, the opening between the rollers 6a and 6b and the opening of the hopper chamber 5 depending on the pressing force of the pressing device 12 and the properties of the gas hydrate powder n as a raw material. The above-mentioned substantially wedge-shaped lump (blocking plug) may be produced in 5a.

  In such a case, warm water h1 (for example, 60 ° C.) is supplied from the thermostat into the hopper chamber 5 through the heat medium pipe 2 of the side plate 1a.

  The supply amount and temperature of the hot water h1 are preferably adjusted as appropriate depending on the size of the hopper chamber, the axial length of the forming roller, the temperature of the supplied gas hydrate powder, and the like.

Then, the plug b formed by the mass of gas hydrate powder supplied with the hot water h1 receives the heat of the hot water h1 and releases a gas (natural gas such as methane or propane) for a short time (for example, 3 to 3). Melt (decompose) in 6 minutes). And the warm water h1 which gave the heat | fever to the obstruction | occlusion stopper b is drained through the drain pipe 4 as the drainage h2.

  The generated gas is reused as a raw material gas for a gas hydrate powder production apparatus or the like through a gas recovery line.

  With the molding apparatus A according to the present invention, the burden on the operation of removing the substantially wedge-shaped lump (blocking plug) generated in the hopper chamber 5 of the molding apparatus is remarkably reduced, and the time required for the removal is from several hours. Reduced to a few minutes.

  In addition, although this embodiment demonstrated what supplies a hot water in the hopper chamber 5, since the high pressure jet is made to collide with the lump b by the nozzle 3, cold water (for example, about 1-4 degreeC) is used. Also good.

  Also, a plurality of movable nozzles can be provided below the side plates 1a and 1b of the hopper chamber 5 so that a high-pressure jet can collide intensively at a predetermined location. In this case, the lump b can be dissolved more effectively.

Furthermore, in order to prevent the gas hydrate powder n from being clogged in the opening 5a inside the hopper chamber 5 of the drain pipe 4, a pipe for circulating the warm water around the pipe in the side plate 1b provided with this pipe is provided. It is also possible to prevent the powder from clogging in the drain pipe 4.

It is a schematic block diagram of one embodiment of the shaping | molding apparatus which concerns on this invention. (A) is a side view, (b) is a top view. FIG. 2 is a perspective view of FIG. 1. It is a schematic block diagram of the conventional shaping | molding apparatus.

Explanation of symbols

A Forming device h1 Warm water h2 Drainage h3 Squeezed water 1, 1a, 1b Side plate 2 Heat medium pipe 3 Jet nozzle 4 Drain pipe 5 Hopper chamber 6a, 6b Molding roller 7 Pocket 9a, 9b Roller shaft 10a, 10b Feeder base 10c, 10d Inclined surface 12 Pushing device 13 Heat medium piping

Claims (2)

In a compression molding apparatus for producing a powdered gas hydrate powder by hydrating a raw material gas and water, and compressing the gas hydrate powder into a substantially spherical shape, the compression molding apparatus includes the gas hydrate. A hopper chamber containing powder, a pair of compression rollers disposed below the opening of the hopper chamber, and a pushing device for supplying gas hydrate powder in the hopper chamber to the compression roller , and from the bottom of at least one side of the hopper chamber to said pair of compression rollers to supply hot water or cold water, other surface features and be Carlo over La-type compression molding apparatus to be drained from the bottom. Roller-type compression molding apparatus 請 Motomeko 1 wherein you characterized in that a hot or cold water jet nozzle at the bottom of at least one side of the hopper chamber.

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