Melting device, melting method, and double pipe

Abstract

Provided is a melting device for discharging a melt of a substance to the inside of a tank to melt the substance stored in the tank, the melting device being capable of discharging a desired amount of the melt into the tank, while reducing the diameter of a discharge pipe that discharges the melt of the substance. The melting device (1) of the present invention comprises a suction pipe (2) and a discharge pipe (3) that are attached to the wall of a tank (T); and a circulation flow path (4) that is disposed outside the tank (T). The inside of the tank (T) and the inside of one end (4a) of the circulation flow path (4) communicate with each other through the inside of the suction pipe (2). The inside of the tank (T) and the inside of the other end (4b) of the circulation flow path (4) communicate with each other through the inside of the discharge pipe (3). A pump (5) is provided at a midway position of the circulation flow path (4). By driving the pump (5), a melt (Ma) of substance (M) that is present inside the tank (T) can be suctioned into the suction pipe (2), circulated through the circulation flow path (4), and discharged from the inside of the discharge pipe (3) to the inside of the tank (T); and the entirety of the inside of the discharge pipe (3) is used as a flow path for the melt (Ma).

Description

Melting equipment, melting method, double pipe

[0001] The present invention relates to a melting device and a double pipe that discharge a melting liquid of a substance into the inside of a tank in order to melt the substance stored inside the tank, and a method for melting a substance using the melting device.

[0002] Conventionally, in international trade, oils and fats that are solid at room temperature are transported by ship. During this transportation, liquid oils and fats are poured into tanks at the point of departure (the country where the oils and fats are produced) and the tanks are loaded onto the ship. Then, at the destination (the country where the oils and fats are imported), the oils that have solidified in the tanks during transportation are melted.

[0003] Flexible vinyl tanks are used as tanks for transporting the above-mentioned oils and fats, and Patent Document 1 discloses a technology for melting substances that have solidified inside the flexible tank during transportation using a heat exchanger (the heat exchanger 200 shown in Figures 14 to 16 is a schematic representation of the heat exchanger disclosed in Patent Document 1).

[0004] The heat exchanger of Patent Document 1 (heat exchanger 200 shown in FIGS. 14 to 16 ) has a second pipe 203 disposed inside a first pipe 202, a third pipe 206 disposed inside the second pipe 203, and a fourth pipe 207 disposed inside the third pipe 206, and a suction port 201 for sucking in a substance M in a tank T ( FIGS. 15 and 16 ) is formed by the gap between the first pipe 202 and the second pipe 203. A plurality of discharge ports 205 for discharging a heated substance Ma into the tank T are formed in the peripheral wall of the second pipe 203. Hot water P flows inside the third pipe 206 and the fourth pipe 207 (specifically, hot water P flows from the space outside the fourth pipe 207 inside the third pipe 206 to the inside of the fourth pipe 207).

[0005] When transportation is performed, a heat exchanger 200 is placed in the flexible tank T at the departure point, and then the flexible tank T is filled with a liquid substance M. When the tank T arrives at the destination, in order to melt the substance M in the tank T that has solidified during transportation, the substance M in the tank T is sucked into the heat exchanger 200 from the suction port 201 by driving a centrifugal pump, where heat exchange occurs between the substance M and hot water P in the heat exchanger 200, and the substance Ma heated by this heat exchange is discharged into the tank T from the discharge port 205 (FIG. 15). In this way, the heated substance Ma circulates within the tank T and exchanges heat with the unmelted substance M, thereby melting the substance M in the tank T.

[0006] Patent No. 4639228

[0007] Incidentally, a typical flexible tank T is fitted with a valve whose dimensions are determined by standards (Figures 10 and 11 described below show a valve 50 fitted to a typical flexible tank T), and any pipe that can be inserted into the hole of this valve can be easily fitted to the flexible tank (in other words, the pipe can be fitted to the tank by the simple process of inserting the pipe into the hole of the valve and fixing the pipe to the valve, etc.).

[0008] In this regard, the heat exchanger of Patent Document 1 (heat exchanger 200 shown in FIGS. 14 to 16 ) requires a third pipe 206 and a fourth pipe 20 to be disposed inside a second pipe 203 having a discharge port 205 formed therein in order to exchange heat between the substance M and the hot water P. Therefore, the diameter of the second pipe 203 must be increased in order to allow a desired amount of melt to flow inside the second pipe 203 and be discharged from the discharge port 205. As a result, a situation may arise in which the heat exchanger 200 cannot be inserted into the hole of a valve attached to the flexible tank T. In this case, in order to attach the heat exchanger 200 to the tank T, for example, it is necessary to remove the existing valve from the tank T, attach a custom-made valve with a larger hole to the tank T instead, and then insert the heat exchanger 200 into the hole of the valve. This work may require considerable effort and cost.

[0009] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide a melting device that discharges a melt of a substance into the interior of a tank to melt the substance stored therein, the melting device being capable of discharging a desired amount of melt into the tank while keeping the diameter of the discharge pipe for discharging the melt of the substance small, and a method for melting a substance stored therein using the melting device. Another object of the present invention is to provide a double-pipe that discharges a melt of a substance into the interior of a tank to melt the substance stored therein, the double-pipe being capable of discharging a desired amount of melt into the tank while keeping the diameter of the pipe for discharging the melt small.

[0010] To achieve the above object, the present invention includes the following subject matter.

[0011] Item 1. A melting device that discharges a melt of a substance into the interior of a tank in order to melt the substance stored inside the tank, comprising: a suction pipe attached to the wall of the tank; a discharge pipe attached to the wall of the tank; a circulation flow path located outside the tank; and a hopper capable of storing the melt of the substance and connected to the circulation flow path via an on-off valve, wherein the interior of the tank communicates with the interior of one end of the circulation flow path via the interior of the suction pipe, and the interior of the tank communicates with the interior of the other end of the circulation flow path via the interior of the discharge pipe, a pump is provided midway along the circulation flow path, and by driving the pump, the melt of the substance present inside the tank can be sucked into the interior of the suction pipe, circulated through the circulation flow path, and discharged from the interior of the discharge pipe into the interior of the tank, the entire interior of the discharge pipe being used as a flow path for the melt, and wherein a primary hopper and a secondary hopper are provided as the hoppers, and the primary hopper is connected to the primary side of the pump in the circulation flow path via a primary on-off valve, The melting device, wherein the secondary hopper is connected to the secondary side of a pump in the circulation flow path via a secondary on-off valve, and the pump is a pump capable of reversing the direction of pressure-feeding of the fluid.

[0012] Item 2. The melting device according to Item 1, wherein a metal tube is wrapped around the outer peripheral surface of the hopper, and when the substance is placed in the hopper, steam or hot water is caused to flow inside the metal tube, thereby melting the substance placed in the hopper and storing the molten liquid in the hopper.

[0013] Item 3. A melting device that discharges a melt of a substance into the interior of a tank in order to melt the substance stored inside the tank, comprising: a suction pipe attached to a wall of the tank; a discharge pipe attached to the wall of the tank; and a circulation flow path located outside the tank, wherein the interior of the tank communicates with the interior of one end of the circulation flow path through the interior of the suction pipe; and the interior of the tank communicates with the interior of the other end of the circulation flow path through the interior of the discharge pipe, a pump is provided midway along the circulation flow path, and by driving the pump, the melt of the substance present inside the tank can be sucked into the interior of the suction pipe, circulated through the circulation flow path, and discharged from the interior of the discharge pipe into the interior of the tank, the entire interior of the discharge pipe being used as a flow path for the melt, the discharge pipe being composed of a mixing ejector equipped with a nozzle section and a diffuser section, and the nozzle section injects the melt sent through the circulation flow path into the interior of the diffuser section, The diffuser section sucks in the molten liquid present in the tank by reducing the pressure caused by the molten liquid being sprayed from the nozzle section, and sprays the sucked-in molten liquid into the inside of the tank together with the molten liquid sprayed from the nozzle section.

[0014] Item 4. A method for melting a substance stored inside a tank using a melting device, the melting device discharging a melt of a substance into the inside of the tank in order to melt the substance stored inside the tank, the method comprising: a suction pipe attached to a wall of the tank; a discharge pipe attached to the wall of the tank; a circulation flow path located outside the tank; and a hopper capable of storing the melt of the substance and connected to the circulation flow path via an on-off valve, the inside of the tank communicating with the inside of one end of the circulation flow path through the inside of the suction pipe, and the inside of the tank communicating with the inside of the other end of the circulation flow path through the inside of the discharge pipe, a pump is provided at a midpoint of the circulation flow path, and by driving the pump, the melt of the substance present inside the tank can be sucked into the inside of the suction pipe, circulated through the circulation flow path, and discharged from the inside of the discharge pipe into the inside of the tank, the entire inside of the discharge pipe being used as a flow path for the melt, the method comprising the steps of: removing a portion of the substance solidified inside the tank; a step of storing in the hopper a molten liquid obtained by melting the substance removed from the tank; a step of driving the pump with the on-off valve open to supply the molten liquid stored in the hopper into the inside of the discharge pipe through the circulation flow path and discharge the molten liquid from the opening at the tip of the discharge pipe into the inside of the tank, thereby melting the substance present in the tank and present near the discharge pipe to form the molten liquid; and a step of driving the pump with the on-off valve closed to suck the molten liquid present in the tank into the inside of the suction pipe, supply it into the inside of the discharge pipe through the circulation flow path, and discharge it from the opening at the tip of the discharge pipe into the inside of the tank, thereby melting the substance present in an unmelted state inside the tank.

[0015] Item 5. A double pipe that discharges a melt of a substance into the interior of a tank in order to melt the substance stored inside the tank, comprising: an outer pipe; an inner pipe that passes through the inside of the outer pipe; and a coupling; the interior of the tank and the interior of one end of a circulation flow path communicate through the space outside the inner pipe inside the outer pipe, and the interior of the tank and the interior of the other end of the circulation flow path communicate through the inside of the inner pipe; by driving a pump provided at a midpoint of the circulation flow path, the melt of the substance present inside the tank can be sucked into the space outside the inner pipe inside the outer pipe, circulated through the circulation flow path, and discharged from the inside of the inner pipe into the interior of the tank, the entire inside of the inner pipe being used as a flow path for the melt; the coupling comprises a cylindrical coupling body and a lever that can be tiltably attached to the coupling body; the base end side of the coupling body is fitted over the tip side of the outer pipe; By tilting the lever, the range of the lever that protrudes into the inside of the coupling body can be reduced, and by tilting the lever in the opposite direction, the range of the lever that protrudes into the inside of the coupling body can be increased; the inner tube passes through the inside of the outer tube and the inside of the coupling body; the base end side of the inner tube extends from a position on the base end side of the outer tube, and at the position on the base end side of the outer tube, the gap between the outer tube and the inner tube is blocked by an annular member; and the tip side of the inner tube is a double tube that extends from the tip of the coupling body.

[0016] Item 6. The double pipe according to Item 5, wherein the double pipe is a combination of a first member and a second member, wherein the first member comprises a base end side of the outer pipe, the annular member, and the inner pipe, wherein the second member comprises a tip side of the outer pipe and the coupling, wherein a first flange is provided on the base end side of the outer pipe and a second flange is provided on the tip side of the outer pipe, wherein the first flange and the second flange each protrude radially outward of the outer pipe and extend in the circumferential direction of the outer pipe, wherein the first member and the second member are combined to form the double pipe by abutting the first flange and the second flange and fastening them with bolts, and wherein the double pipe can be disassembled into the first member and the second member by releasing the fastening of the bolts.

[0017] Item 7. A melting device that discharges a melt of a substance into the inside of a tank in order to melt the substance stored inside the tank, comprising: a suction pipe attached to a wall of the tank; a discharge pipe attached to the wall of the tank; and a circulation flow path located outside the tank, wherein the inside of the tank communicates with the inside of one end of the circulation flow path through the inside of the suction pipe, and the inside of the tank communicates with the inside of the other end of the circulation flow path through the inside of the discharge pipe, a pump is provided midway along the circulation flow path, and by driving the pump, the melt of the substance present inside the tank can be sucked into the inside of the suction pipe, circulated through the circulation flow path, and discharged from the inside of the discharge pipe into the inside of the tank, the entire inside of the discharge pipe being used as a flow path for the melt, the substance is wax or oil, the tank is made of vinyl or metal, and the melting device does not have a cooling means for cooling the substance stored inside.

[0018] Item 8. The melting device according to Item 7, wherein the discharge pipe having a small diameter is disposed inside the suction pipe having a large diameter, and the inside of the tank communicates with the inside of one end of the circulation flow path through a space inside the suction pipe and outside the discharge pipe.

[0019] Item 9. The melting device according to Item 7, further comprising a hopper capable of storing a melt of the substance, the hopper being connected to the circulation flow path via an on-off valve.

[0020] Item 10. The melting apparatus according to Item 9, wherein a metal tube is wound around the outer peripheral surface of the hopper, and when the substance is placed in the hopper, steam or hot water is caused to flow inside the metal tube, thereby melting the substance placed in the hopper and storing the molten liquid in the hopper.

[0021] Item 11. The melting apparatus according to Item 7, further comprising a heating means embedded in the wall of the tank.

[0022] Item 12. The melting device according to Item 7, further comprising a heating means disposed outside the tank and in contact with the wall of the tank.

[0023] Item 13. The melting device according to Item 7, further comprising a heating means disposed inside the tank.

[0024] Item 14. The melting apparatus according to any one of Items 11 to 13, wherein the heating means is a pipe through which hot water or steam flows.

[0025] Item 15. The melting device according to any one of Items 11 to 13, wherein the heating means is a pad provided with a conductor that generates heat by electrical resistance.

[0026] Item 16. The melting device according to any one of Items 11 to 13, wherein the direction of the discharge pipe is adjusted so that the melted liquid discharged from inside the discharge pipe into the tank is directed toward the position of the heating means.

[0027] Item 17. The melting device according to Item 7, further comprising a melt heating means provided midway along the circulation flow path for heating the melt flowing through the circulation flow path.

[0028] Item 18. The melting device according to Item 7, wherein a spray nozzle for spraying the melting liquid in a spray form is attached to the tip of the discharge pipe.

[0029] Item 19. The melting device according to Item 7, further comprising a gas supply means capable of supplying heated gas to the circulation channel.

[0030] Item 20. A double pipe that discharges a melt of a substance into the interior of a tank to melt the substance stored inside the tank, comprising: an outer pipe; and an inner pipe that passes through the inside of the outer pipe; the interior of the tank and the interior of one end of a circulation flow path communicate through the space outside the inner pipe inside the outer pipe, and the interior of the tank and the interior of the other end of the circulation flow path communicate through the inside of the inner pipe; by driving a pump provided at a midpoint of the circulation flow path, the melt of the substance present inside the tank can be sucked into the space outside the inner pipe inside the outer pipe, circulated through the circulation flow path, and discharged from the inside of the inner pipe into the interior of the tank, the entire inside of the inner pipe being used as a flow path for the melt; the substance is wax or oil; the tank is made of vinyl or metal, and is a double pipe that does not have a cooling means for cooling the substance stored inside.

[0031] According to the melting device and melting method of the present invention, the entire interior of the discharge pipe is used as a flow path for the molten liquid, making it possible to discharge the desired amount of molten liquid from the discharge pipe while keeping the diameter of the discharge pipe small.

[0032] Furthermore, with the double pipe of the present invention, the entire interior of the inner pipe is used as a flow path for the molten liquid of the substance, making it possible to discharge the desired amount of molten liquid into the inside of the tank while keeping the diameter of the inner pipe that discharges the molten liquid small.

[0033] 3( a ) is a schematic diagram showing a melting device according to an embodiment of the present invention; FIG. 3( b ) is a schematic diagram showing the internal state of a tank to which the melting device according to an embodiment of the present invention is applied; FIG. 3( a ) is a schematic diagram showing a suction pipe and a discharge pipe, with FIG. 3( a ) being a perspective view and FIG. 3( b ) being a cross-sectional view; FIG. 3( b ) is an image showing a double pipe constituting the suction pipe and the discharge pipe; FIG. 3( b ) is an image showing a double pipe constituting the suction pipe and the discharge pipe; FIG. 3( b ) is an image showing a double pipe constituting the suction pipe and the discharge pipe; FIG. 3( b ) is an image showing a coupling provided in the double pipe; FIG. 3( b ) is an image showing a coupling provided in the double pipe;

[0034] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described with reference to the accompanying drawings. Fig. 1 is a schematic diagram showing a melting device 1 according to an embodiment of the present invention. Fig. 2 is a schematic diagram showing the interior of a tank T to which the melting device 1 of this embodiment is applied.

[0035] The melting device 1 of this embodiment discharges a molten liquid Ma of a substance M into the tank T in order to melt the substance M stored inside the tank T. The tank T is a flexible tank made of vinyl, and is filled with a substance M that is solid at room temperature. The substance M is, for example, wax or fats and oils (esters of glycerin and fatty acids).

[0036] 1, the melting device 1 includes a suction pipe 2 and a discharge pipe 3 attached to the wall of the tank T, a circulation flow path 4 disposed outside the tank T, and a pump 5 provided midway along the circulation flow path 4. In the melting device 1, the interior of the tank T communicates with the interior of one end 4a of the circulation flow path 4 via the interior of the suction pipe 2, and the interior of the tank T communicates with the interior of the other end 4b of the circulation flow path 4 via the interior of the discharge pipe 3. By driving the pump 5, a melt Ma of a substance M present in the tank T can be sucked into the suction pipe 2, circulated through the circulation flow path 4, supplied to the inside of the discharge pipe 3, and discharged into the inside of the tank T from an opening 3s at the tip of the discharge pipe 3. The heat of the molten liquid Ma discharged into the tank T melts the unmelted substance M present in the tank T into molten liquid Ma, which is then sucked into the suction pipe 2 and discharged into the tank T, melting the unmelted substance M remaining in the tank T into molten liquid Ma. The configuration of the melting device 1 will now be described in detail.

[0037] 3A and 3B are schematic diagrams showing a double pipe 6 according to this embodiment, with Fig. 3A being a perspective view and Fig. 3B being a cross-sectional view. The melting device 1 of this embodiment is provided with a double pipe 6 including an outer pipe constituting the suction pipe 2 and an inner pipe constituting the discharge pipe 3 (hereinafter, the reference numeral "2" for the suction pipe will be used to refer to the outer pipe, and the reference numeral "3" for the discharge pipe will be used to refer to the inner pipe).

[0038] The double pipe 6 has the inner pipe 3 (discharge pipe) passing through the inside of the outer pipe 2, and connects the inside of the tank T to the inside of one end 4a of the circulation flow path 4 through a space K outside the inner pipe 3 (discharge pipe) inside the outer pipe 2 (suction pipe), and also connects the inside of the tank T to the inside of the other end 4b of the circulation flow path 4 through the inside of the inner pipe 3 (discharge pipe) (FIG. 1). With the melting device 1 equipped with the double pipe 6, by driving the pump 5 provided in the circulation flow path 2, it is possible to suck in a melt Ma of the substance M present inside the tank T into the space K, circulate it through the circulation flow path 4, and discharge it from inside the inner pipe 3 (discharge pipe) into the inside of the tank T, and the space K and the entire inside of the inner pipe 3 (discharge pipe) are used as a flow path for the melt Ma.

[0039] 4 to 6 are images showing an example of the double pipe 6. The double pipe 6 shown in Figures 4 to 6 includes an outer pipe 2 which is a suction pipe, an inner pipe 3 which is a discharge pipe, and a coupling 7. The outer pipe 2 and the inner pipe 3 are made of metal such as stainless steel, or resin (in the illustrated example, the outer pipe 2 and the inner pipe 3 are made of stainless steel (SUS304 JIS5K)).

[0040] 4 to 6, the outer tube 2 (suction tube) has an outer tube main body 8 and a base end tube 9. The base end tube 9 extends from the base end side 8b of the outer tube main body 8, and the extending direction of the base end tube 9 is inclined with respect to the extending direction of the outer tube main body 8. Note that in the example shown in FIGS. 4 to 6, the extending direction of the base end tube 9 is perpendicular to the extending direction of the outer tube main body 8, but it does not have to be perpendicular.

[0041] 7 and 8 are enlarged images of the coupling 7. The coupling 7 includes a cylindrical coupling body 10 and two levers 11A and 11B attached to the coupling body 10 so as to be tiltable. The coupling body 10 is cylindrical with open ends and made of resin. The base end of the coupling body 10 is fitted over the tip end of the outer tube 2 (the tip end 8c of the outer tube body 8) (FIGS. 4 to 6). More specifically, the tip end 8b of the outer tube body 8 is inserted into the base end of the coupling body 10, and a screw formed on the inner surface of the coupling body 10 is threadedly engaged with a screw formed on the outer surface of the outer tube body 8, thereby fixing the base end of the coupling body 10 to the tip end 8b of the outer tube body 8. The coupling body 10 may be fixed to the outer tube body 8 by known means other than screws. The coupling body 10 may also be made of rubber or metal.

[0042] Two pairs of protrusions 12, 12 are provided on the outer surface of the coupling body 10 (FIG. 8). The two pairs of protrusions 12, 12 are provided at relative positions in the radial direction, and a shaft member 13 is attached to each pair of protrusions 12, 12. The shaft member 13 extends from one protrusion 12 to the other protrusion 12.

[0043] One end 11a of a lever 11 is inserted between each pair of projections 12, 12, and a shaft member 13 passes through the one end 11a of the lever 11. A through hole 10b (FIG. 8) is formed in the coupling body 10 between the projections 12, 12. This through hole 10b extends radially inward from the outer surface of the coupling body 10 and opens to the inner surface of the coupling body 10, and the one end 11a of the lever is inserted into this through hole 10b. As shown in the lower lever 11A of FIG. 8, by gripping the other end of the lever 11 and tilting the lever 11, the extent to which the one end 11a of the lever 11 protrudes from the through hole 10b into the coupling body 10 can be reduced. Then, by tilting the lever 11 in the opposite direction, the extent to which the one end 11a of the lever 11 protrudes from the through hole 10b into the coupling body 10 can be increased, as shown in the upper lever 11B of FIG. 8.

[0044] The inner pipe 3 (discharge pipe) passes through the inside of the outer pipe body 8 and the inside of the coupling body 10. The inside of the base end pipe 9 communicates with the space outside the inner pipe 3 in the outer pipe body 8 and the coupling body 10 (corresponding to space K shown in Figure 3).

[0045] 4 to 6, the base end side 3a of the inner pipe 3 extends from a position on the base end side of the outer pipe 2 (specifically, the position of the base end 8a of the outer pipe main body 8). As shown in Fig. 6, at the position on the base end side of the outer pipe 2 (the position of the base end 8a of the outer pipe main body 8), the gap between the outer pipe main body 8 and the inner pipe 3 is closed by the annular member 14 (the outer peripheral edge of the annular member 14 is welded to the outer pipe main body 8, and the inner peripheral edge of the annular member 14 is welded to the inner pipe 3). The tip side 3b (Figs. 4 to 6) of the inner pipe 3 extends from the tip of the coupling body 10.

[0046] The double pipe 6 described above is formed by combining two members (a first member and a second member). The first member includes the base end side of the outer pipe 2 (specifically, the base end side 8b of the outer pipe main body 8 and the base end pipe 9), the annular member 14 ( FIG. 6 ), and the inner pipe 3. The second member includes the tip end side of the outer pipe 2 (specifically, the tip end side 8c of the outer pipe main body 8) and the coupling 7. A first flange 22 is provided on the base end side 8b of the outer pipe main body 8, and a second flange 23 is provided on the tip end side 8c of the outer pipe main body 8. These flanges 22, 23 protrude radially outward from the outer pipe main body 8 and extend in the circumferential direction of the outer pipe main body 8. The first flange 22 and the second flange 23 are butted against each other and fastened together with bolts 24 to combine the first and second members to form the double pipe 6. The double pipe 6 can be disassembled into the first and second members by releasing the fastening of the bolts 24.

[0047] The circulation flow path 4 (FIG. 1) is formed by connecting flexible metal hoses (diameter 32A) made of, for example, SUS304, and a connector specified in JIS 10K can be used to connect the flexible metal hoses together.

[0048] When the double pipe 6 shown in Figures 4 to 6 is used, the pipe constituting one end 4a (Figures 1, 5, and 6) of the circulation flow path 4 is connected to the base end side (more specifically, base end pipe 9) of the outer pipe 2 (suction pipe), so that the "interior of the tank T" and the "interior of one end 4a of the circulation flow path 4" communicate with each other via the "interior of the outer pipe 2" (the "interior of the outer pipe 2" above corresponds to the "interior of the base end pipe 9" and the "space outside the inner pipe 3 within the outer pipe main body 8 and the coupling main body 10"). Furthermore, the pipe constituting the other end 4b (Figures 1, 5, and 6) of the circulation flow path 4 is connected to the base end of the inner pipe 3 (discharge pipe), so that the "interior of the tank T" and the "interior of the other end 4b of the circulation flow path 4" communicate with each other via the "interior of the inner pipe 3 (discharge pipe)." 1, 5, and 6, a first on-off valve 30 is provided in the pipe forming one end 4a of the circulation flow path 4, and a second on-off valve 31 is provided in the pipe forming the other end 4b of the circulation flow path 4. In the example shown in FIGS. 5 and 6, the other end 4b of the circulation flow path 4 is composed of an L-shaped joint pipe 4b-1 and a straight pipe 4b-2, and the straight pipe 4b-2 is provided with the second on-off valve 31. The base end of the inner pipe 3 is connected to one end of the joint pipe 4b-1 with a screw, and the other end of the joint pipe 4b-1 is connected to one end of the straight pipe 4b-2 with a screw. Note that the joint pipe 4b-1 may be omitted, and the base end of the inner pipe 3 may be connected to the straight pipe 4b-2, on which the second on-off valve 31 is provided, with a screw or the like.

[0049] The base end pipe 9 may be omitted from the outer pipe 2, and a pipe constituting one end 4a of the circulation flow path 4 may be connected to the base end side 8b of the outer pipe main body 8. In this case, the "interior of the tank T" and the "interior of one end 4a of the circulation flow path 4" are communicated via the "space outside the inner pipe 3 inside the outer pipe main body 8 or the coupling main body 10." The first member is also said to include the base end side 8b of the outer pipe main body 8 (the base end side of the outer pipe 2), the annular member 14 (FIG. 6), and the inner pipe 3.

[0050] In this embodiment, a pump capable of reversing the direction of fluid pressure is provided as the pump 5 (FIG. 1) provided midway along the circulation flow path 4. For example, a rotary pump can be used as this pump.

[0051] Furthermore, in addition to the pump 5, the circulation flow path 4 (FIG. 1) is provided with a thermometer 40, a pressure gauge 41, a sight glass 42, a primary hopper 43A, and a secondary hopper 43B. The pressure gauge 41 measures the pressure of the melt Ma of the substance M being pumped through the circulation flow path 4 by the pump 5. The thermometer 40 measures the temperature of the melt Ma flowing through the circulation flow path 4. The sight glass 42 is a tube with a glass window, and the state of the melt Ma flowing through the circulation flow path 4 can be observed through the window.

[0052] The primary hopper 43A and the secondary hopper 43B are capable of storing a melt Ma of the substance M. The primary hopper 43A is connected to the primary side of the pump 5 in the circulation flow path 4 via a primary third on-off valve 44A. The secondary hopper 43B is connected to the secondary side of the pump 5 in the circulation flow path 4 via a secondary third on-off valve 44B.

[0053] According to the configuration of the melting apparatus 1 described above, by driving the rotary pump 5 in the forward direction with the first on-off valve 30 closed and the second on-off valve 31 and the primary-side third on-off valve 44A open, the molten liquid Ma stored in the primary-side hopper 43A can be circulated through the circulation flow path 4 and supplied to the inside of the inner pipe 3 (discharge port), and then discharged from the opening 3s at the tip of the inner pipe 3 into the inside of the tank T. Furthermore, by opening the secondary-side third on-off valve 44B, a portion of the molten liquid Ma flowing through the circulation flow path 4 can be caused to flow into the secondary-side hopper 43B, allowing the state of the molten liquid Ma to be observed.

[0054] Furthermore, by driving the rotary pump 5 in the forward direction with the first on-off valve 30 and the second on-off valve 31 open, the molten liquid Ma present in the tank T can be sucked into the outer pipe 2 (suction pipe), circulated through the circulation flow path 4, supplied to the inner pipe 3 (discharge pipe), and discharged from the opening 3s of the inner pipe 3 into the inside of the tank T. Furthermore, by opening the third on-off valves 44A and 44B, a portion of the molten liquid Ma flowing through the circulation flow path 4 can be caused to flow into the hoppers 43A and 43B, allowing the state of the molten liquid Ma to be observed.

[0055] Furthermore, by driving the rotary pump 5 in the reverse direction with the first on-off valve 30 and the second on-off valve 31 open, it is possible to reverse the flow of the molten liquid Ma in the circulation flow path 4. In other words, the molten liquid Ma present in the tank T can be sucked into the inner pipe 3, circulated in the circulation flow path 4, and discharged from the space K outside the inner pipe 3 inside the outer pipe 2 into the inside of the tank T.

[0056] Next, a method for melting the solidified substance M in the tank T using the melting device 1 of this embodiment will be described.

[0057] First, a step of removing a portion of the solidified substance M from the tank T is carried out (step S101 in FIG. 9).

[0058] 10 and 11 is attached to the wall of the tank T, a portion of the solidified substance M inside the tank T is removed through a hole 51 in the valve 50. The structure of the valve 50 will be described below.

[0059] The valve 50 includes a cylindrical body 52 and an annular member (not shown). An annular flange 53 is provided at the base end of the cylindrical body 52. ​​The flange 53 protrudes radially outward from the cylindrical body 52 and extends in the circumferential direction of the cylindrical body 52.

[0060] The annular member (not shown) has an outer diameter that matches the outer diameter of the flange 53 and an inner diameter that matches the inner diameter of the cylindrical body 52. ​​A through-hole (not shown) is formed in the wall of the tank T at the position where the valve 50 is attached, and the diameter of the through-hole approximately matches the inner diameter of the cylindrical body 52 and the annular member.

[0061] When attaching the valve 50 to the tank T, the internal space of the cylindrical body 52, the through-hole formed in the wall of the tank T, and the internal space of the annular member are connected, and the wall of the tank T is sandwiched between the flange 53 and the annular member, and then the flange 53 and the annular member are fastened together with bolts 54 (the bolts 54 penetrate the wall of the tank T). The "valve hole 51" is formed by the connection between the "internal space of the cylindrical body 52," the "through-hole formed in the wall of the tank T," and the "internal space of the annular member."

[0062] As shown in Figures 10 and 11, the cylindrical body 52 is provided with a ball 56 and a lever 57 fastened to the ball 56. The ball 56 is a hollow sphere and is disposed inside the cylindrical body 52. ​​Two through holes 58, 58 are formed in the wall of the ball 56 (one of the through holes 58 is shown in Figure 10). The two through holes 58, 58 are opposed to each other in the radial direction of the ball 56, and the diameters of these through holes 58, 58 are approximately the same as the inner diameter of the cylindrical body 52. ​​The lever 57 extends from the ball 56 radially outward of the cylindrical body 52 and penetrates the cylindrical body 52, and a handle 59 is provided at the tip of the lever 57 that extends from the cylindrical body 52.

[0063] With the valve 50 described above, by gripping the handle 59 and rotating the lever 57, it is possible to rotate the ball 56 within the cylindrical body 52 and position the two through-holes 58, 58 on the axis of the cylindrical body 52. ​​By performing this operation, it is possible to open the hole 51 of the valve 50 as shown in Figure 10. Furthermore, by rotating the ball 56 by rotating the lever 57, it is possible to change the position of the through-holes 58, 58 and close the hole 51 of the valve 50 by the wall of the ball 56 as shown in Figure 11.

[0064] If the above-described valve 50 is provided in the tank T, in step S101, first, the hole 51 of the valve 50 is opened by rotating the lever 57 (the valve 50 is set to the state shown in FIG. 10 ). Next, a hand drill (not shown) is inserted into the tank T through the hole 51 of the valve 50 and rotated to scrape off a portion of the substance M that has solidified inside the tank T. Thereafter, the hand drill is withdrawn from the hole 51 of the valve 50, and the substance M scraped off by the hand drill is removed to the outside of the tank T. Note that the method for removing the substance M from the tank T in step S101 is not limited to the above method. For example, if the tank T is provided with a removable lid, the lid may be removed to remove the substance M from the tank T.

[0065] After step S101, the material M removed from the tank T is melted to obtain a molten liquid Ma, which is then stored in the primary hopper 43A (step S102 in FIG. 9).

[0066] In step S102, for example, the substance M removed from the tank T is melted using a heater (such as a stove), and the molten liquid Ma obtained by this melting is poured into the primary hopper 43A. Alternatively, a metal tube may be wrapped around the outer periphery of the primary hopper 43A in order to melt the substance M in the primary hopper 43A. In this case, in step S102, steam or hot water is flowed through the metal tube while the substance M removed from the tank T is poured into the primary hopper 43A. As a result, the substance M poured into the primary hopper 43A is melted by the heat of the steam or hot water, and the molten liquid Ma is stored in the hopper 43A.

[0067] After step S102, the suction pipe 2 and the discharge pipe 3 are connected to the tank T, the second on-off valve 31 and the primary-side third on-off valve 44A (FIG. 1) are opened, and the first on-off valve 30 is closed, and the pump 5 is driven in the forward direction (step S103). As a result, the molten liquid Ma stored in the primary-side hopper 43A is circulated through the circulation flow path 4 and supplied to the inside of the discharge pipe 3, and is discharged from the opening 3s of the discharge pipe 3 into the inside of the tank T. Then, as shown in FIG. 1, the heat of the discharged molten liquid Ma melts the substance M present in the tank T, which is present near the discharge pipe 3, to become the molten liquid Ma.

[0068] 4 to 6, and when the valve 50 shown in Figures 10 and 11 is attached to the wall of the tank T, in step S103, the double pipe 6 is attached to the valve 50, thereby attaching the suction pipe 2 and the discharge pipe 3 to the wall of the tank T. The work of attaching the double pipe 6 to the valve 50 will be described below.

[0069] First, as shown by the lower lever 11A in FIG. 8, the range in which one end 11a of the lever 11 projects into the coupling body 10 is reduced by tilting the lever 11.

[0070] Next, the lever 57 is rotated to open the hole 51 of the valve 50 (the state shown in FIG. 10). The inner pipe 3 (FIGS. 4 to 8) is inserted into the hole 51 of the valve 50, causing the tip of the inner pipe 3 to protrude into the interior of the tank T (FIGS. 1 and 2), and the tip side 10a (FIGS. 4 to 6) of the coupling body 10 is fitted onto the cylindrical body 52 (FIG. 10) of the valve 50. This places the interior of the outer pipe 2 (suction pipe) and the interior of the inner pipe 3 (discharge pipe) in communication with the interior of the tank T. Note that if the material M inside the tank T is scraped off in step S101, the tip of the inner pipe 3 is inserted into the hole in the material M that was created by the scraping.

[0071] Next, by tilting the lever 11, the "extent by which the one end 11a of the lever 11 protrudes into the coupling body 10" is increased, as shown by the upper lever 11B in Figure 8. As a result, the one end 11a of the lever 11 is pressed firmly against the cylindrical body 52, and the double pipe 6 is attached to the valve 50.

[0072] In order to attach the double pipe 6 to the valve 50 in the above-described procedure, the outer diameter of the inner pipe 3 must be smaller than the inner diameter of the cylindrical body 52 so that the inner pipe 3 can be inserted into the cylindrical body 52. ​​Furthermore, the inner diameter of the coupling body 10 must be approximately the same as the outer diameter of the cylindrical body 52 so that the cylindrical body 52 can be inserted into the coupling body 10 and the double pipe 6 can be fixed by the lever 11 abutting against the cylindrical body 52. ​​Furthermore, the procedure for attaching the double pipe 6 to the valve 50 (the procedure for connecting the suction pipe 2 and the discharge pipe 3 to the tank T) may be performed before step S102.

[0073] 8, by tilting the lever 11, the "extent by which the one end 11a of the lever 11 protrudes into the coupling body 10" can be reduced, as in the case of the lower lever 11A in Figure 8, thereby weakening the pressure of the one end 11a of the lever 11 against the cylindrical body 52. ​​This allows the double pipe 6 to be removed from the valve 50 (i.e., the double pipe 6 (suction pipe 2 and discharge pipe 3) can be removed from the tank T).

[0074] 9 , the first on-off valve 30 and the second on-off valve 31 are opened, and the pump 5 is driven in the normal direction to suck the molten liquid Ma present in the tank T into the suction pipe 2, circulate the molten liquid Ma through the circulation flow path 4, and supply it to the inside of the discharge pipe 3, where it is discharged from the opening 3s of the discharge pipe 3 into the tank T (step S104). While step S104 is being performed, the heat of the molten liquid Ma discharged into the tank T melts the substance M present in the tank T in an unmelted state. More specifically, in step S104, the molten liquid Ma previously discharged from the discharge pipe 3 and the molten liquid Ma melted by the heat of the molten liquid Ma are repeatedly sucked into the suction pipe 2 and discharged from the discharge pipe 3. As a result, the amount of molten liquid Ma discharged from the discharge pipe 3 (i.e., the amount of molten liquid Ma sucked from the suction pipe 2) increases over time, and the area in which the substance M is melted within the tank T gradually expands from the vicinity of the discharge pipe 3 (Figure 2).

[0075] If the temperature of the molten liquid Ma in the tank T drops and the substance M no longer melts, the operation of the pump 5 is temporarily stopped, and the high-temperature molten liquid Ma is stored, for example, in the primary hopper 43A. Thereafter, the pump 5 is driven in the normal direction with the first on-off valve 30 closed and the second on-off valve 31 and the primary-side third on-off valve 44A open. In this manner, the high-temperature molten liquid Ma is supplied to the inside of the tank T, allowing the melting of the substance M to be resumed (i.e., the molten liquid Ma stored in the hopper 43A can be used as prime oil for resuming melting).

[0076] According to the melting apparatus 1 and double pipe 6 of the present embodiment described above, the entire interior of the discharge pipe 3 (inner pipe) that discharges the melt Ma of the substance M is used as a flow path for the melt Ma. Therefore, it is possible to discharge a desired amount of melt from the discharge pipe 3 (inner pipe) while keeping the diameter of the discharge pipe 3 (inner pipe) small. Furthermore, because the diameter of the discharge pipe 3 (inner pipe) can be kept small, the hole of an existing valve in the tank T can be used as the hole for inserting the discharge pipe 3 (inner pipe). This eliminates the need to remove the existing valve from the tank T, replace it with a custom-made valve with a larger hole, and then insert the discharge pipe into the valve hole, as in the prior art. In the present invention, the discharge pipe refers to a pipe that is inserted into a hole in the wall of the tank T and attached directly or indirectly to the wall of the tank T, and is connected by screws, welding, or the like to a pipe (such as a joint pipe or a pipe equipped with a valve) that constitutes the end of the circulation flow path 4, and is used to discharge the melt Ma flowing through the circulation flow path 4 into the interior of the tank T. In the examples shown in Figures 4 to 8, the discharge pipe 3 (inner pipe) is integrated with the suction pipe 2 (outer pipe), and the discharge pipe 3 (inner pipe) is inserted into a hole in a valve 50 provided in the wall of the tank T, and the suction pipe 2 (outer pipe) is attached to the valve 50, so that the suction pipe 2 (outer pipe) is directly attached to the wall of the tank T, and the discharge pipe 3 (inner pipe) is indirectly attached to the wall of the tank T via the suction pipe 2 (outer pipe).

[0077] Furthermore, according to the melting apparatus 1 of this embodiment, if the length of the discharge pipe 3 (inner pipe 3) extending into the tank T is shortened, it is not necessary to lengthen the hole for the material M into which the tip of the discharge pipe 3 (inner pipe 3) is inserted. This reduces the effort required to drill a hole in step S101 of FIG. 9 . Furthermore, according to this embodiment, the material M obtained by drilling the hole is melted to obtain molten liquid Ma to be stored in the primary hopper 43A, and this molten liquid Ma is supplied into the tank T and serves as the starting oil for melting. As a result, the material M obtained by drilling the hole is effectively utilized and not wasted.

[0078] Furthermore, according to the melting apparatus 1 of this embodiment, if a blockage occurs in the circulation flow path 4, the suction pipe 2, or the discharge pipe 3, the blockage can be cleared by driving the rotary pump 5 in the reverse direction to reverse the pumping direction of the molten liquid Ma. Furthermore, since hoppers are connected to the primary and secondary sides of the pump 5, one of these hoppers can be used to store the molten liquid Ma that will serve as prime oil, and the other hopper can be used to sample the molten liquid Ma flowing through the circulation flow path 4.

[0079] Furthermore, according to the melting apparatus 1 of this embodiment, the rotary pump 5 capable of reverse rotation is used, so that the high-temperature molten liquid Ma stored in the secondary hopper 43B can be discharged from the inner pipe 3 (suction pipe 2), and the heat of the discharged molten liquid Ma can melt the material M in the tank T. Since this is possible, a metal pipe may be wrapped around the outer circumferential surface of not only the primary hopper 43A but also the secondary hopper 43B. In this way, by flowing steam or hot water inside the metal pipe, the material M introduced into the secondary hopper 43B can be melted, and the molten liquid Ma can be stored in the secondary hopper 43B.

[0080] Furthermore, if a metal pipe is wrapped around the hopper 43A or hopper 43B, when the melting device 1 is placed in a low-temperature environment (such as a cold region), steam or hot water can be flowed through the metal pipe, and the heat of the steam or hot water can heat the circulation flow path 4. Therefore, the molten liquid Ma flowing through the circulation flow path 4 can be prevented from freezing.

[0081] Furthermore, with the double pipe 6 of this embodiment, when a valve 50 (FIGS. 10 and 11) is attached to the flexible tank T, the inner pipe 3 (FIGS. 4 to 8) can be attached to the valve 50 by making the outer diameter of the inner pipe 3 smaller than the inner diameter of the cylindrical body 52 (FIGS. 10 and 11) and by making the inner diameter of the coupling body 10 (FIGS. 4 to 8) approximately equal to the outer diameter of the cylindrical body 52 (FIGS. 10 and 11).

[0082] Furthermore, according to the double pipe 6 of this embodiment, it can be disassembled into two members (a first member and a second member), so that if a problem such as clogging occurs in the double pipe 6, the problem can be easily resolved.

[0083] The present invention is not limited to the above-described embodiments, and various modifications can be made.

[0084] For example, the melting apparatus 1 of the present invention may include a heating means 70 disposed inside the tank T, as shown in FIG. 12( a). In this case, the heating means 70 is a pipe through which hot water or steam flows, preferably a Benri pipe. An example of such a Benri pipe is a rolled flexible water pipe (RFL25) manufactured by Libilac Co., Ltd. Alternatively, the heating means 70 may be a heater pad provided with a conductor that generates heat through electrical resistance. By providing the heating means 70 (pipe or heater pad), the heat generated by the heating means 70 heats and melts the substance M in the tank T. Furthermore, the molten, high-temperature liquid is sucked through the suction pipe 2 and discharged into the tank T through the discharge pipe 3, thereby quickly melting the solidified substance M in the tank T.

[0085] When the heating means 70 is a pipe through which hot water flows, the hot water in the hot water tank T is supplied to the pipe (heating means 70) via the first flow path by the pressure of the pump 5, and the hot water supplied to the pipe is returned to the hot water tank via the second flow path. When the heating means 70 is a pipe through which steam flows, the steam generated by the steam mixer is supplied to the pipe (heating means 70) via the first flow path, and the steam supplied to the pipe is discharged via the second flow path.

[0086] 12(b), the heating means 70 (tube or heater pad) may be embedded in the wall of the tank T. Alternatively, as shown in FIG. 12(c), the heating means 70 may be disposed outside the tank T and abut against the wall of the tank T. In this way, it is not necessary to dispose the heating means 70 inside the tank T, and therefore it is possible to prevent the tank T from cracking due to contact with the heating means 70.

[0087] Furthermore, when the above-described heating means 70 is provided in the melting apparatus 1, the direction of the discharge pipe 3 is adjusted so that the molten liquid Ma discharged from the inside of the discharge pipe 3 into the inside of the tank T heads toward the position of the heating means 70, as shown in Figures 12(a), (b), and (c). In this way, the molten liquid Ma discharged from the discharge pipe 3 can be heated by the heating means 70, allowing the high-temperature molten liquid Ma to circulate within the tank T. This allows the substance M in the tank T to melt more quickly. When the double pipe 6 shown in Figures 4 to 8 is used, the tip 3c of the discharge pipe 3 can be bent as shown in the illustrated example to direct the molten liquid Ma discharged from the opening 3s of the discharge pipe 3 into the inside of the tank T toward the position of the heating means 70.

[0088] Since the present invention aims to melt the substance M stored inside the tank T, the tank T does not have a cooling means for cooling the substance M stored inside.

[0089] Furthermore, the melting apparatus 1 of the present invention does not necessarily need to include two hoppers 43A, 43B; only one of the hoppers 43A, 43B may be provided. Furthermore, the hopper 43 may be omitted. Even in this case, if the melting apparatus 1 is provided with the heating means 70, the heat generated by the heating means 70 can be used to melt the solidified substance M in the tank T. The resulting molten liquid Ma can be sucked through the suction pipe 2 and discharged through the discharge pipe 3, thereby melting the substance M in the tank T. Alternatively, the substance M removed from the tank T can be melted using a heater (such as a stove), and the resulting molten liquid Ma can be poured into the tank T. In this case, the molten liquid Ma poured into the tank T can be sucked through the suction pipe 2 and discharged through the discharge pipe 3 to serve as a starting oil for melting the substance. Furthermore, when the tank T is used to transport the substance M, a molten liquid of the substance prepared at the destination (i.e., a molten liquid of the substance that was not stored in the tank T during transportation) can be poured into the tank T. Even in this case, the melt of the substance introduced into the tank T can be sucked through the suction pipe 2 and discharged through the discharge pipe 3, so that the melt of the substance introduced into the tank T, Ma, can be used as a priming oil to trigger the melting of the substance. The melt of the substance introduced into the tank T may be a melt of the same type of substance as the substance stored in the tank T during transportation, or it may be a melt of a different type of substance from the substance stored in the tank T.

[0090] The melting device 1 may also be provided with a molten liquid heating means for heating the molten liquid Ma flowing through the circulation flow path 4. The molten liquid heating means is a heat exchanger that exchanges heat between steam or hot water and the molten liquid Ma. Alternatively, the molten liquid heating means is a heater equipped with a conductor that generates heat through electrical resistance. In this case, for example, the molten liquid heating means (heater) is disposed so that the conductor is in contact with a pipe that constitutes the circulation flow path 4, and the heat of the conductor is transferred to the molten liquid Ma flowing through the circulation flow path 4.

[0091] Furthermore, in the melting apparatus 1 of the present invention, the discharge pipe 3 and the suction pipe 2 do not necessarily need to be configured using the double pipe 6; the discharge pipe 3 and the suction pipe 2 may be attached separately and independently to the wall of the tank T. If the double pipe 6 is used, the discharge pipe 3 and the suction pipe 2 are both attached by attaching the double pipe 6 to the tank T, thereby reducing the effort required for attachment. Furthermore, if the double pipe 6 is used, the discharge pipe 3 and the suction pipe 2 can be arranged coaxially, so that the molten liquid Ma discharged from the discharge pipe 3 can be reliably sucked into the suction pipe 2. This allows the molten liquid Ma to be continuously discharged from the discharge pipe 3, allowing the substance M to be continuously melted.

[0092] Furthermore, in the melting apparatus 1 of the present invention, instead of the pump 5 capable of reversing the fluid pumping direction, a pump whose pumping direction is limited to one direction may be provided in the circulation flow path 4. Even in this case, by driving the pump, the molten liquid Ma present in the tank T can be sucked into the suction pipe 2, supplied to the inside of the discharge pipe 3 via the circulation flow path 4, and discharged into the tank T from the opening 3s of the discharge pipe 3, thereby melting the substance M in the tank T. Note that a rotary pump or a centrifugal pump can be used as the "pump whose pumping direction is limited to one direction," and an LDP type line pump (50LPD62.2A) manufactured by Ebara Corporation can be used as the centrifugal pump, for example.

[0093] The discharge pipe 3 may also be composed of a mixing ejector including a nozzle and a diffuser. The nozzle injects the melted liquid Ma delivered through the circulation flow path 4 into the diffuser. The diffuser sucks the melted liquid Ma present in the tank T by reducing the pressure caused by the melted liquid Ma being ejected from the nozzle, and then injects the sucked melted liquid Ma into the tank T together with the melted liquid Ma ejected from the nozzle. Using the above-described mixing ejector as the discharge pipe 3 allows a large amount of melted liquid Ma present around the discharge pipe 3 to be sucked through the suction pipe 2 without requiring power (electricity, etc.), thereby increasing the amount of melted liquid Ma circulating in the circulation flow path 4. This improves the energy efficiency of the melting apparatus 1 (i.e., the amount of material melted per unit time can be increased while minimizing the energy required to drive the melting apparatus 1). The above-described mixing ejector can be, for example, the Mixing Eductor 3MP manufactured by Yamamoto Sangyo Co., Ltd.

[0094] A spray nozzle for spraying the molten liquid Ma in a spray form may be attached to the tip of the discharge pipe 3. Use of the spray nozzle described above can promote the agitation of the molten liquid Ma in the tank T, thereby accelerating the melting of the substance M. Note that, for example, a TURBO DISC manufactured by Japan Howard Co., Ltd. can be used as the spray nozzle described above.

[0095] The melting apparatus 1 of the present invention may also be provided with a gas supply means capable of supplying gas to the circulation flow path 4. When the gas supply means is used, gas bubbles are ejected into the tank T together with the melt Ma from the discharge pipe 3, thereby promoting the agitation of the melt Ma in the tank T. As the gas supply means, for example, a gas-liquid shear type microbubble generator (BL12AA-12-D4 direct operation type) manufactured by Nitta Moore Corporation can be used. When a flexible tank T is used as the tank T, the gas ejected into the tank T can be discharged from a safety valve provided on the flexible tank T.

[0096] Furthermore, the substance M that can be melted by the melting device 1 of the present invention is not limited to wax and fats. The object to be melted by the melting device 1 of the present invention can be any of various substances that can be melted by the heat of the melting liquid Ma.

[0097] The tank T for storing the substance M to be melted is not limited to a flexible vinyl tank, and a tank T made of a material other than vinyl may be used. For example, the tank T may be a metal ISO (International Organization for Standardization) tank. In this case, the suction pipe 2 and the discharge pipe 3 are attached to the wall of the ISO tank by known means.

[0098] 13 , in the melting apparatus 1 of the present invention, a discharge flow path 80 for discharging the melt Ma flowing through the circulation flow path 4 may be connected to the circulation flow path 4. In this case, a fourth on-off valve 81 may be provided in the discharge flow path 80, and by opening the on-off valve 81, a portion of the melt Ma flowing through the circulation flow path 4 can be directed to the discharge flow path 80. Furthermore, a fifth on-off valve 82 may be provided in the circulation flow path 4 at a position downstream of the connection point of the discharge flow path 80. In this case, by opening the fourth on-off valve 81 and closing the fifth on-off valve 82, all of the melt Ma flowing through the circulation flow path 4 can be directed to the discharge flow path 80. Furthermore, when the discharge flow path 80 is provided as described above, for example, the melt Ma flowing through the discharge flow path 80 may be introduced into a tank 84 of a truck 83, and the melt Ma may be transported by the truck 83.

[0099] The inventors conducted an experiment to compare the performance of the melting device of the embodiment of the present invention with the performance of the melting device of the comparative example. This experiment will be described below.

[0100] The following operations were carried out to confirm the performance of the melting device according to the embodiment of the present invention.

[0101] After inserting a Benri pipe (heating means 70) into the flexible tank T, 110 kg of palm mid-fraction (PMF) was filled into the tank T. The tank T was then left in a room at 20°C for three days to solidify the oil in the tank T. A hand drill was then inserted into the tank T through a hole in the tank T, and some of the solidified oil was scraped off by rotating the hand drill, creating a hole in the oil. Next, a double pipe 6 was attached to the tank T so that the tip of the discharge pipe 3 could fit into the hole, and the circulation flow path 4 was connected to the double pipe 6. The scraped oil was then poured into the primary hopper 43A and melted. After that, 0.7 m of hot water at 70°C to 80°C was poured into the tank T. ３ Water was started to be passed through the Benley pipe (heating means 70) at a flow rate of 1 / h, and with the first on-off valve 30 closed and the second on-off valve 31 and the third on-off valve 44A open, the pump 5 was driven to discharge the molten liquid Ma in the hopper 43A into the tank T. Thereafter, the first on-off valve 30 was opened to suck in the molten liquid Ma present in the tank T and discharge it into the tank T. The temperature of the molten liquid Ma and the state inside the tank T were then checked 4 hours and 5 hours after the time when water began to be passed through the Benley pipe (hereinafter referred to as the water passage start time).

[0102] The melting device of the comparative example was the melting device of the example, except that the double pipe 6 and the circulation flow path 4 were omitted. The following procedure was carried out to confirm the performance of the melting device of the comparative example.

[0103] After inserting the Benri pipe into the flexible tank T, 110 kg of palm mid-fraction (PMF) was filled into the tank T. After that, the tank T was left in a room at 20°C for 3 days to solidify the oil in the tank T. Then, 0.7 m of hot water at 70°C to 80°C was poured into the tank T. ３ Water was then started to flow through the Benly pipe at a flow rate of 1000 / h. The temperature of the molten liquid Ma and the state inside the tank T were checked 4 hours and 5 hours after the start of water flow through the Benly pipe (hereinafter referred to as the water flow start time).

[0104] The results confirmed through the above work are shown in Table 1 below.

[0105]

[0106] As shown in Table 1, in the melting device of the example using the double pipe 6 and the circulation flow path 4, the temperature of the molten liquid Ma was higher 4 hours and 5 hours after the start of water flow compared to the melting device of the comparative example not using the double pipe 6 and the circulation flow path 4. Furthermore, in the melting device of the example, all of the oil in the tank T was melted after 4 hours, whereas in the melting device of the comparative example, solid oil (unmelted oil) remained in the tank even after 5 hours. From the above, it was confirmed that the melting device of the present invention using the double pipe 6 and the circulation flow path 4 can quickly melt the oils and fats in the tank T (in other words, it was confirmed that the oils and fats in the tank T can be quickly melted by sucking the molten liquid in the tank T and discharging the molten liquid into the tank T).

[0107] REFERENCE SIGNS LIST 1 Melting device 2 Suction pipe (outer pipe) 3 Discharge pipe (inner pipe) 3a Base end side of inner pipe 4 Circulation flow path 4a One end of circulation flow path 4b Other end of circulation flow path 5 Pump 6 Double pipe 7 Coupling 8c Tip side of outer pipe main body (tip side of outer pipe) 10 Coupling main body 10a Tip side of coupling main body 11A, 11B Lever 22 First flange 23 Second flange 43 Hopper 43A Primary side hopper 43B Secondary side hopper 44 Third on-off valve (on-off valve) 44A Primary side third on-off valve (primary side on-off valve) 44B Secondary side third on-off valve (secondary side on-off valve) 70 Heating means M Substance Ma Melted liquid of substance, T Tank

Claims

1. A melting device that discharges a melt of a substance into the interior of a tank in order to melt the substance stored inside the tank, comprising: a suction pipe attached to the wall of the tank; a discharge pipe attached to the wall of the tank; a circulation flow path located outside the tank; and a hopper capable of storing the melt of the substance and connected to the circulation flow path via an on-off valve, wherein the interior of the tank communicates with the interior of one end of the circulation flow path via the interior of the suction pipe, and the interior of the tank communicates with the interior of the other end of the circulation flow path via the interior of the discharge pipe, a pump is provided midway along the circulation flow path, and by driving the pump, the melt of the substance present inside the tank can be sucked into the interior of the suction pipe, circulated through the circulation flow path, and discharged from the interior of the discharge pipe into the interior of the tank, the entire interior of the discharge pipe being used as a flow path for the melt, and wherein a primary hopper and a secondary hopper are provided as the hoppers, and the primary hopper is connected to the primary side of the pump in the circulation flow path via a primary on-off valve, The melting device, wherein the secondary hopper is connected to the secondary side of a pump in the circulation flow path via a secondary on-off valve, and the pump is capable of reversing the direction of pressure-feeding of the fluid.

2. A melting device as described in claim 1, wherein a metal tube is wrapped around the outer periphery of the hopper, and when the substance is placed in the hopper, steam or hot water is passed through the inside of the metal tube, thereby melting the substance placed in the hopper and storing the molten liquid in the hopper.

3. A melting device that discharges a melt of a substance into the interior of a tank in order to melt the substance stored inside the tank, comprising: a suction pipe attached to the wall of the tank; a discharge pipe attached to the wall of the tank; and a circulation flow path located outside the tank, the interior of the tank communicates with the interior of one end of the circulation flow path through the interior of the suction pipe, and the interior of the tank communicates with the interior of the other end of the circulation flow path through the interior of the discharge pipe, a pump is provided midway along the circulation flow path, and by driving the pump, the melt of the substance present inside the tank can be sucked into the interior of the suction pipe, circulated through the circulation flow path, and discharged from the interior of the discharge pipe into the interior of the tank, the entire interior of the discharge pipe being used as a flow path for the melt, the discharge pipe being composed of a mixing ejector equipped with a nozzle section and a diffuser section, the nozzle section injects the melt sent through the circulation flow path into the interior of the diffuser section, The diffuser section sucks in the molten liquid present in the tank by reducing the pressure caused by the molten liquid being sprayed from the nozzle section, and sprays the sucked-in molten liquid into the inside of the tank together with the molten liquid sprayed from the nozzle section.

4. A method for melting a substance stored inside a tank using a melting device, the melting device discharging a melt of a substance into the tank in order to melt the substance stored inside the tank, the melting device comprising: a suction pipe attached to a wall of the tank; a discharge pipe attached to the wall of the tank; a circulation flow path arranged outside the tank; and a hopper capable of storing the melt of the substance and connected to the circulation flow path via an on-off valve, the inside of the tank communicating with the inside of one end of the circulation flow path through the inside of the suction pipe, and the inside of the tank communicating with the inside of the other end of the circulation flow path through the inside of the discharge pipe, a pump is provided at a position midway along the circulation flow path, and by driving the pump, the melt of the substance present inside the tank can be sucked into the inside of the suction pipe, circulated through the circulation flow path, and discharged from the inside of the discharge pipe into the inside of the tank, the entire inside of the discharge pipe being used as a flow path for the melt, the method comprising the steps of: removing a portion of the substance solidified inside the tank; a step of storing in the hopper a molten liquid obtained by melting the substance removed from the tank; a step of driving the pump with the on-off valve open to supply the molten liquid stored in the hopper into the inside of the discharge pipe through the circulation flow path and discharge the molten liquid from the opening at the tip of the discharge pipe into the inside of the tank, thereby melting the substance present in the tank and present near the discharge pipe to form the molten liquid; and a step of driving the pump with the on-off valve closed to suck the molten liquid present in the tank into the inside of the suction pipe, supply it into the inside of the discharge pipe through the circulation flow path, and discharge it from the opening at the tip of the discharge pipe into the inside of the tank, thereby melting the substance present in an unmelted state inside the tank.

5. A double pipe for discharging a melt of a substance into the interior of a tank in order to melt the substance stored therein, comprising an outer pipe, an inner pipe passing through the interior of the outer pipe, and a coupling, wherein the interior of the tank communicates with the interior of one end of a circulation flow path through the space outside the inner pipe inside the outer pipe, and the interior of the tank communicates with the interior of the other end of the circulation flow path through the interior of the inner pipe, and by driving a pump provided at a midpoint of the circulation flow path, the melt of the substance present inside the tank can be sucked into the space outside the inner pipe inside the outer pipe, circulated through the circulation flow path, and discharged from the inside of the inner pipe into the interior of the tank, and the entire interior of the inner pipe is used as a flow path for the melt, and the coupling comprises a cylindrical coupling body and a lever attached to the coupling body so as to be able to tilt freely, and the base end side of the coupling body is fitted over the tip side of the outer pipe, By tilting the lever, the range of the lever that protrudes into the inside of the coupling body can be reduced, and by tilting the lever in the opposite direction, the range of the lever that protrudes into the inside of the coupling body can be increased; the inner tube passes through the inside of the outer tube and the inside of the coupling body; the base end side of the inner tube extends from a position on the base end side of the outer tube, and at the position on the base end side of the outer tube, the gap between the outer tube and the inner tube is blocked by an annular member; and the tip side of the inner tube is a double tube that extends from the tip of the coupling body.

6. The double pipe according to claim 5, wherein the double pipe is a combination of a first member and a second member, wherein the first member comprises the base end side of the outer pipe, the annular member, and the inner pipe, wherein the second member comprises the tip end side of the outer pipe and the coupling, wherein a first flange is provided on the base end side of the outer pipe and a second flange is provided on the tip end side of the outer pipe, wherein the first flange and the second flange each protrude radially outward of the outer pipe and extend in the circumferential direction of the outer pipe, and wherein the first member and the second member are combined to form the double pipe by butting the first flange and the second flange together and fastening them with bolts, and wherein the double pipe can be disassembled into the first member and the second member by releasing the fastening of the bolts.

7. A melting device that discharges a melt of a substance into the inside of a tank in order to melt the substance stored inside the tank, comprising: a suction pipe attached to the wall of the tank; a discharge pipe attached to the wall of the tank; and a circulation flow path arranged outside the tank, the inside of the tank and the inside of one end of the circulation flow path are connected through the inside of the suction pipe, and the inside of the tank and the inside of the other end of the circulation flow path are connected through the inside of the discharge pipe, a pump is provided at a position midway through the circulation flow path, and by driving the pump, the melt of the substance present inside the tank can be sucked into the inside of the suction pipe, circulated through the circulation flow path, and discharged from the inside of the discharge pipe into the inside of the tank, the entire inside of the discharge pipe being used as a flow path for the melt, the substance is wax or oil, the tank is made of vinyl or metal, and the melting device does not have a cooling means for cooling the substance stored inside.

8. The melting device according to claim 7, wherein the small-diameter discharge pipe is disposed inside the large-diameter suction pipe, and the interior of the tank communicates with the interior of one end of the circulation flow path through the space outside the discharge pipe inside the suction pipe.

9. The melting device according to claim 7, further comprising a hopper capable of storing a melt of the substance, said hopper being connected to said circulation flow path via an on-off valve.

10. A melting apparatus as described in claim 9, wherein a metal tube is wrapped around the outer periphery of the hopper, and when the substance is placed in the hopper, steam or hot water is passed through the inside of the metal tube, thereby melting the substance placed in the hopper and storing the molten liquid in the hopper.

11. The melting apparatus of claim 7, further comprising heating means embedded in the wall of said tank.

12. The melting apparatus of claim 7, further comprising heating means disposed outside the tank and abutting the wall of the tank.

13. The melting apparatus of claim 7, further comprising a heating means disposed within said tank.

14. A melting apparatus according to any one of claims 11 to 13, wherein the heating means is a pipe through which hot water or steam flows.

15. A melting apparatus according to any one of claims 11 to 13, wherein the heating means is a pad provided with a conductor that generates heat by electrical resistance.

16. A melting device according to any one of claims 11 to 13, wherein the direction of the discharge pipe is adjusted so that the melted liquid discharged from inside the discharge pipe into the inside of the tank is directed toward the position of the heating means.

17. The melting apparatus according to claim 7, further comprising a melt heating means provided midway along the circulation flow path for heating the melt flowing through the circulation flow path.

18. The melting device according to claim 7, wherein a spray nozzle for spraying the melting liquid in a spray form is attached to the tip of the discharge pipe.

19. The melting apparatus according to claim 7, further comprising a gas supply means capable of supplying heated gas to the circulation channel.

20. A double pipe that discharges a molten liquid of a substance into the interior of a tank to melt the substance stored inside the tank, comprising: an outer pipe; and an inner pipe that passes through the inside of the outer pipe; the interior of the tank communicates with the interior of one end of a circulation flow path through the space outside the inner pipe inside the outer pipe, and the interior of the tank communicates with the interior of the other end of the circulation flow path through the inside of the inner pipe; by driving a pump provided at a position midway along the circulation flow path, the molten liquid of the substance present inside the tank can be sucked into the space outside the inner pipe inside the outer pipe, circulated through the circulation flow path, and discharged from the inside of the inner pipe into the interior of the tank; the entire inside of the inner pipe is used as a flow path for the molten liquid; the substance is wax or oil; the tank is made of vinyl or metal; and the double pipe does not have a cooling means for cooling the substance stored inside.