Vaporizer System

Abstract

To provide a vaporizer system capable of increasing a temperature of a road surface by causing a heat medium of a vaporizer to flow through an underground pipe in a snowy region, to be used for road heating.SOLUTION: A vaporizer system comprises: first underground pipes R3, R9, R6 partially routed underground; a first switching valve 7 that switches communication between a vaporizer 3 and second normal pipes R3, R5, R6 and communication between the vaporizer 3 and the first underground pipes R3, R9, R6; a first temperature sensor TH1 that measures a second normal pipe temperature T1, which is a temperature of the second normal pipes R3, R5, R6; and a control device 9 that controls the first switching valve 7 according to the second normal pipe temperature T1. When the second normal pipe temperature T1 is equal to or higher than a first predetermined temperature TT1, the control device 9 switches from the communication between the vaporizer 3 and the second normal pipes R3, R5, R6 to the communication between the vaporizer 3 and the first underground pipes R3, R9, R6 by the first switching valve 7.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vaporizer system. [Background technology]

[0002] Conventionally, vaporizers that forcibly vaporize LP gas such as propane gas are known. Such vaporizers are devices that vaporize LP gas more efficiently than natural vaporization by passing the liquid LP gas through a heat medium such as hot water heated by a heat source such as an electric heater or a boiler.

[0003] Such vaporizers are equipped with various sensors and are controlled based on the detection values ​​of the sensors (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-159566 A Summary of the Invention [Problem to be solved by the invention]

[0005] For example, if a vaporizer is installed in a snowy region or other snowy area, if there is snow around the vaporizer during regular inspection, snow removal work will be required before the inspection, which will reduce the efficiency of the inspection work.

[0006] The present invention has been made in consideration of the above, and aims to provide a vaporizer system that allows the heat transfer medium of the vaporizer to be used for road heating to raise the temperature of the road surface by flowing it through underground piping in snowy areas. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems and achieve the object, the present invention provides a gas container for storing liquid fuel gas, a vaporizer for introducing liquid fuel gas from the gas container and vaporizing it by heating, a heat source device for heating the liquid fuel gas, a first normal pipe for directly supplying a medium from the heat source device to the vaporizer, a second normal pipe for returning the medium discharged from the vaporizer directly to the heat source device, a first underground pipe for returning the medium discharged from the vaporizer to the heat source device and having a portion thereof passing underground, and a base The vaporizer includes a first switching valve that switches between communication between the vaporizer and the second normal piping and communication between the vaporizer and the first underground piping, a first temperature sensor that measures a second normal piping temperature, which is the temperature of the second normal piping, and a control device that controls the first switching valve in accordance with the second normal piping temperature, wherein when the second normal piping temperature is equal to or higher than a first predetermined temperature, the control device switches from communication between the vaporizer and the second normal piping to communication between the vaporizer and the first underground piping using the first switching valve.

[0008] In order to solve the above-mentioned problems and achieve the object, the present invention provides a gas container for storing liquid fuel gas, a vaporizer for introducing liquid fuel gas from the gas container and vaporizing it by heating, a heat source device for heating the liquid fuel gas, a first normal pipe for directly supplying a medium from the heat source device to the vaporizer, a second normal pipe for directly returning the medium discharged from the vaporizer to the heat source device, a first underground pipe for returning the medium discharged from the vaporizer to the heat source device and part of which passes underground, a second underground pipe for supplying the medium from the heat source device to the vaporizer and part of which passes underground, a first switching valve for switching communication between the vaporizer and the second normal pipe and communication between the vaporizer and the first underground pipe, a second switching valve for switching communication between the heat source device and the first normal pipe and communication between the heat source device and the second underground pipe, and a second switching valve for switching communication between the heat source device and the first normal pipe and communication between the heat source device and the second underground pipe. The control device is provided with a first temperature sensor that measures a normal piping temperature, and a control device that controls the first and second switching valves according to the second normal piping temperature, and when the second normal piping temperature is equal to or higher than a second predetermined temperature, the control device switches from communication between the vaporizer and the second normal piping to communication between the vaporizer and the first underground piping using the first switching valve, and switches from communication between the heat source unit and the first normal piping to communication between the heat source unit and the second underground piping using the second switching valve, when the second normal piping temperature is equal to or higher than a third predetermined temperature that is lower than the second predetermined temperature, the second switching valve switches from communication between the heat source unit and the first normal piping to communication between the heat source unit and the second underground piping, and when the second normal piping temperature is equal to or higher than a fourth predetermined temperature that is lower than the third predetermined temperature, the control device switches from communication between the vaporizer and the second normal piping to communication between the vaporizer and the first underground piping using the first switching valve. Effect of the Invention

[0009] The vaporizer system according to the present invention has an effect that it can be used for road heating, which increases the temperature of the road surface by flowing the heat medium of the vaporizer through underground piping in snowy areas. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a configuration diagram of a vaporizer system according to the first embodiment. [Diagram 2] FIG. 2 is a diagram showing a control flow of the vaporizer system in the first embodiment. [Diagram 3] FIG. 3 is a diagram showing a control flow of a vaporizer system in a modified example of the first embodiment. [Figure 4] FIG. 4 is a configuration diagram of a vaporizer system according to the second embodiment. [Diagram 5] FIG. 5 is a diagram showing a control flow of the vaporizer system in the second embodiment. [Figure 6] FIG. 6 is a diagram showing a control flow of a vaporizer system in a modified example of the second embodiment. [Figure 7] FIG. 7 is a configuration diagram of a vaporizer system 1 in the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vaporizer system according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiment.

[0012] [First embodiment] FIG. 1 is a configuration diagram of a vaporizer system according to the first embodiment.

[0013] The vaporization system 1 in the first embodiment includes a bulk storage tank 2, a vaporizer 3, a heat source unit 4, a liquid gas supply unit 5, a vaporized gas supply unit 6, a first pressure switch PSW1, a second pressure switch PSW2, a first switching valve 7, a first temperature sensor TH1, a second temperature sensor TH2, a third temperature sensor TH3, a first pipe R1 to a ninth pipe R9, a snowfall sensor (not shown), and a control device 9.

[0014] The bulk storage tank 2 is a large-capacity container that stores liquid LP gas (fuel gas). The first pipe R1 is a pipe that serves as a liquid phase line that connects the bulk storage tank 2 and the vaporizer 3 via the liquid gas supply unit 5. The first pipe R1 is connected to the lower part of the bulk storage tank 2 at one end and to a heat exchanger 32 of the vaporizer 3 (described later) at the other end, and introduces liquid LP gas into the vaporizer 3. The liquid gas supply unit 5 is provided on the first pipe R1 and includes at least a thermo valve TV (not shown). The thermo valve TV opens when the temperature (hot water temperature) of the vaporizer 3 is equal to or higher than a certain temperature, and closes when the temperature is lower than the certain temperature.

[0015] The vaporizer 3 introduces liquid LP gas and forcibly vaporizes it by heating it. The vaporizer 3 is a hot water circulation type that forcibly vaporizes the gas by using hot water as a medium, and includes a hot water tank 31 and a heat exchanger 32.

[0016] The hot water tank 31 is a storage unit that stores hot water, and has a hot water inlet 31a and a hot water outlet 31b. The hot water inlet 31a and the hot water outlet 31b are connected to the second pipe R2 and the third pipe R3, respectively. The hot water tank 31 receives hot water heated by the heat source unit 4 from the hot water inlet 31a, and hot water that has been used for evaporation and has been reduced in temperature is discharged from the hot water outlet 31b, and the hot water is returned to the heat source unit 4.

[0017] The second pipe R2 has one end connected to the heat source unit 4 and the other end connected to the hot water inlet 31a.

[0018] The third pipe R3 has one end connected to the hot water outlet 31b, and the other end connected to the fifth pipe R5 and the ninth pipe R9 at a junction A which is a connection portion.

[0019] The fourth pipe R4 is connected at one end to the heat exchanger 32 of the vaporizer 3 and at the other end to the vaporized gas supply unit 6. The fourth pipe R4 introduces the LP gas forcibly vaporized by the vaporizer 3 into the vaporized gas supply unit 6.

[0020] The fifth pipe R5 has one end connected to the third pipe R3 and the ninth pipe R9 at a junction A which is a connection portion, and the other end connected to the first switching valve .

[0021] The heat exchanger 32 introduces liquid LP gas and heats and vaporizes the introduced liquid LP gas by the hot water in the hot water tank 31. The heat exchanger 32 is provided in a coil shape in the hot water tank 31, with one end connected to the first pipe R1 and the other end connected to the fourth pipe R4. The liquid LP gas is introduced into the heat exchanger 32, and is forcibly vaporized by the surrounding hot water while moving from one end to the other end inside the heat exchanger 32, and is then discharged from the vaporizer 3.

[0022] The heat source unit 4 is a boiler or the like that heats water in order to introduce hot water into the vaporizer 3. The heat source unit 4 introduces hot water into the vaporizer 3 via the second pipe R2. The heat source unit 4 also receives hot water drawn out from the vaporizer 3 via the third pipe R3, the fifth pipe R5, and the sixth pipe R6. The heat source unit 4 further includes a pump (not shown) that serves as the power for sending hot water to the vaporizer 3. The heat source unit 4 is electrically connected to the control device 9, and the operation of the heat source unit 4 is controlled by the control device 9.

[0023] The sixth pipe R6 is connected to the first switching valve 7 at one end and to the heat source unit 4 at the other end.

[0024] The seventh pipe R7 is a gas phase line connected at one end to the bulk storage tank 2 and at the other end to the vaporized gas supply unit 6. In the bulk storage tank 2, the liquid LP gas is vaporized due to the ambient temperature. The seventh pipe R7 is connected to the upper part of the bulk storage tank 2 and introduces the LP gas that has naturally vaporized due to the ambient temperature into the vaporized gas supply unit 6.

[0025] The vaporized gas supply unit 6 includes at least a first regulator PR1 (not shown) and a second regulator PR2 (not shown). The first regulator PR1 (not shown) adjusts the pressure of the LP gas introduced from the bulk storage tank 2 through the seventh pipe R7 to a constant pressure. The second regulator PR2 adjusts the pressure of the LP gas introduced from the vaporizer 3 through the fourth pipe to a constant pressure. The outlet set pressure of the second regulator PR2 is set higher than the outlet set pressure of the first regulator PR1. Therefore, when the thermo valve TV provided in the liquid gas supply unit 5 is open, the LP gas is introduced through the liquid phase line. The vaporized gas supply unit 6 supplies the LP gas to the combustion appliance 100 through the eighth pipe R8.

[0026] The eighth pipe R8 is connected to the vaporized gas supply unit 6 at one end and to the combustion appliance 100 at the other end.

[0027] The first pressure switch PSW1 is provided on the seventh pipe R7, turns on when the pressure in the seventh pipe R7 is less than a first predetermined pressure, and when turned on, transmits an on signal to the control device 9. The control device 9 starts the operation of the heat source unit 4 when it receives an on signal from the first pressure switch PSW1, for example.

[0028] The second pressure switch PSW2 turns on when the pressure of the LP gas supplied from the vaporizer 3 via the fourth pipe is lower than a second predetermined pressure, and when turned on, transmits an on signal to the control device 9. For example, when the control device 9 receives an on signal from the second pressure switch PSW2, it determines that the gas volume in the bulk storage tank 2 has decreased or that the thermo valve TV in the liquid gas supply unit has been activated.

[0029] The first switching valve 7 is connected to the fifth pipe R5, the sixth pipe R6, and the ninth pipe R9. The first switching valve 7 switches between communication between the fifth pipe R5 and the sixth pipe R6 and communication between the ninth pipe R9 and the sixth pipe R6. That is, the first switching valve 7 switches between communication between the vaporizer 3 and a second normal pipe described later and communication between the vaporizer 3 and a first underground pipe described later. The first switching valve 7 is electrically connected to the control device 9, and the control device 9 controls the switching.

[0030] The ninth pipe R9 is connected to the third pipe R3 and the fifth pipe R5 at one end at a junction A, which is a connection part, and to the first switching valve 7 at the other end. A part of the ninth pipe R9 passes underground. The ninth pipe R9 usually serves to introduce the hot water introduced from the vaporizer 3 to the heat source unit 4 into the ground and transfer the heat of the hot water into the ground. The ninth pipe R9 also shares the third pipe R3 from the vaporizer 3 to the junction A with the fifth pipe R5.

[0031] Here, the first normal piping in the first embodiment is composed of the second piping R2, the second normal piping is composed of the third piping R3, the fifth piping R5, and the sixth piping R6, and the first underground piping is composed of the third piping R3, the ninth piping R9, and the sixth piping R6. Here, the underground piping in the present invention is buried in the ground in correspondence with the road surface near the vaporizer 3. The road surface is, for example, a road along which a worker walks to inspect the vaporizer 3. The road is, for example, a road laid from the outside of the facility where the vaporizer 3 is located to the vaporizer 3.

[0032] The first temperature sensor TH1 is provided in the third pipe R3 and is a temperature sensor that measures the second normal pipe temperature T1. The first temperature sensor TH1 is electrically connected to the control device 9 and outputs a signal corresponding to the second normal pipe temperature T1 to the control device 9.

[0033] The second temperature sensor TH2 is a temperature sensor that measures the outside air temperature T2. The second temperature sensor TH2 is installed, for example, outside the vaporizer 3 in a state exposed to the atmosphere. The second temperature sensor TH2 is electrically connected to the control device 9 and outputs a signal corresponding to the outside air temperature T2 to the control device 9.

[0034] The third temperature sensor TH3 is a temperature sensor that measures the underground temperature T3. The third temperature sensor TH3 is installed, for example, in the ground where the ninth pipe R9 is buried, at a position that is not affected by the heat of the hot water that is transferred to the ground. The third temperature sensor TH3 is electrically connected to the control device 9, and outputs a signal corresponding to the underground temperature T3 to the control device 9.

[0035] The snowfall sensor (not shown) is electrically connected to the control device 9 and informs the control device 9 of the timing to switch from normal control to snow removal control, which removes snow by road heating, when snow accumulates on the road surface. The snowfall sensor (not shown) is a sensor that detects snowfall when, for example, snow starts to fall, the snow adheres to the sensor, and then melts into water. In this embodiment, the snowfall is detected by the snowfall sensor (not shown) and the timing to switch is automatically determined, but the present invention is not limited to this, and the normal control may be switched to the snowfall control manually. For example, the normal control may be switched to the snowfall control by using an operating device such as a manual switch or a smartphone.

[0036] The control device 9 controls the entire vaporizer system 1, and is a device that controls the first switching valve 7 and the heat source unit 4, and includes a communication unit 9a and a determination unit 9b. The communication unit 9a receives signals from at least the temperature sensors TH1 to TH3, and inputs and outputs control signals for the first switching valve 7 and the heat source unit 4. The determination unit 9b performs switching control of the first switching valve 7 according to the second normal piping temperature T1, the outside air temperature T2, and the underground temperature T3, which are the measurement results of the temperature sensors TH1 to TH3, that is, switches between normal control and snowfall control. Specifically, the first switching valve 7 switches between piping pattern A and piping pattern B.

[0037] Here, the piping pattern A in the first embodiment is a route that passes through the second piping R2, which directly supplies hot water from the heat source unit 4 to the vaporizer 3, i.e., the first normal piping, and through the third piping R3, the fifth piping R5, and the sixth piping R6, i.e., the second normal piping, which directly return the hot water discharged from the vaporizer 3 to the heat source unit 4.

[0038] In addition, piping pattern B in the first embodiment is a route that passes through the second piping R2, which directly supplies hot water from the heat source unit 4 to the vaporizer 3, i.e., the first normal piping, and the third piping R3, the ninth piping R9, and the sixth piping R6, i.e., the first underground piping, which return the hot water discharged from the vaporizer 3 to the heat source unit 4 via the ground.

[0039] In the vaporizer system 1 as described above, the heat source unit 4 is first stopped. At this time, the temperature of the hot water in the vaporizer 3 is approximately the outside air temperature T2, and the thermovalve TV in the liquid gas supply unit 5 is closed.

[0040] Here, when a large amount of LP gas is vaporized in the bulk storage tank 2, the pressure is high and the first pressure switch PSW1 is off. In this case, the heat source unit 4 is not operated, and the LP gas is supplied to the combustion equipment 100, i.e., to the consumer, via the seventh pipe R7 and the eighth pipe R8, which are vapor phase lines.

[0041] When a large amount of LP gas is supplied to the combustion equipment 100 via the seventh pipe R7 and the eighth pipe R8, which are gas-phase lines, the pressure in the bulk storage tank 2 drops. At this time, the first pressure switch PSW1 turns on, and the control device 9 operates the heat source unit 4 by operation control. When the heat source unit 4 operates, the temperature of the hot water in the vaporizer 3 rises and the thermo valve TV in the liquid gas supply unit 5 opens. As a result, the liquid LP gas is forcibly vaporized in the vaporizer 3. The forcibly vaporized LP gas is supplied to the combustion equipment 100 via the fourth pipe R4 and the eighth pipe R8.

[0042] Next, a description will be given of the operation of the vaporizer system 1 in the first embodiment. Fig. 2 is a diagram showing a control flow of the vaporizer system 1 in the first embodiment.

[0043] 2, the control device 9 determines whether or not snow removal is necessary (S101). Here, the control device 9 determines whether or not snow removal is necessary based on the detection of snowfall by a snowfall sensor (not shown).

[0044] Next, when the control device 9 determines that snow removal is necessary (S101=YES), it determines whether the vaporizer 3 is operating (S102). Here, the control device 9 determines whether the thermo valve TV in the liquid gas supply unit 5 is open.

[0045] Next, when the control device 9 determines that the vaporizer 3 is operating (S102=YES), it determines whether the second normal pipe temperature T1 is equal to or higher than TT1 (S103). Here, TT1 is a first predetermined temperature, which is, for example, 65° C. in the first embodiment.

[0046] Next, when the control device 9 determines that the second normal piping temperature T1 is equal to or higher than TT1 (S103=YES), it selects piping pattern B (S104). Here, when the second normal piping temperature T1 is equal to or higher than the first predetermined temperature TT1, the control device 9 uses the first switching valve 7 to connect the vaporizer 3 to the first underground piping, and circulates hot water in the order of the heat source device 4, the vaporizer 3, the underground, and the heat source device 4.

[0047] Next, the control device 9 judges whether the second normal piping temperature T1 is equal to or higher than TT2 (S105). Here, TT2 is a temperature lower than TT1, and is, for example, 55° C. in the first embodiment.

[0048] Next, when the control device 9 determines that the second normal piping temperature T1 is equal to or higher than TT2 (S105=YES), it maintains the piping pattern B (S104).

[0049] Furthermore, when the control device 9 determines that snow removal is not necessary (S101=NO), determines that the second normal piping temperature T1 is not equal to or higher than TT1 (S103=NO), or determines that the second normal piping temperature is not equal to or higher than TT2 (S105=NO), it selects piping pattern A (S106). Here, when the control device 9 determines that snow removal is not necessary, that the second normal piping temperature T1 is less than the first predetermined temperature TT1, or that the second normal piping temperature T1 is less than TT2, it uses the first switching valve 7 to connect the vaporizer 3 to the second normal piping, and circulates hot water in the order of the heat source unit 4, the vaporizer 3, and the heat source unit 4.

[0050] Moreover, when the control device 9 determines that the vaporizer 3 is not operating (S102=NO), it selects the piping pattern B (S104).

[0051] According to this embodiment, the hot water returning from the vaporizer 3 to the heat source unit 4, i.e., hot water at a higher temperature than the temperature around the underground piping, is circulated through underground piping buried underground corresponding to the road surface that requires snow removal, thereby raising the temperature of the road surface and making it possible to use the temperature for road heating.

[0052] [Modification of the first embodiment] Next, another operation of the vaporizer system 1 in the first embodiment will be described. Fig. 3 is a diagram showing a control flow of the vaporizer system 1 in a modified example of the first embodiment. Note that this modified example is premised on the fact that it is executed when there is no snowfall, such as in summer, i.e., when no snowfall is detected by a snowfall sensor (not shown).

[0053] First, the control device 9 judges whether the outside air temperature T2 is equal to or higher than TT3 (S110), where TT3 is, for example, 5° C. in this modified example.

[0054] Next, when the controller 9 determines that the outside air temperature T2 is equal to or higher than TT3 (S110=YES), the controller 9 determines whether or not the vaporizer 3 is operating (S111).

[0055] Next, when the control device 9 determines that the vaporizer 3 is operating (S111=YES), it determines whether the outside air underground temperature difference ΔT1 (=T3-T2), which is the temperature difference between the underground temperature T3 and the outside air temperature T2, is equal to or greater than ΔTT1 (S112). Here, ΔTT1 is a first predetermined temperature difference, which is, for example, 2°C in this modified example.

[0056] Next, when the control device 9 determines that the outside air underground temperature difference ΔT1 is equal to or greater than ΔTT1 (S112=YES), it selects piping pattern B (S113). Here, when the outside air underground temperature difference ΔT1 is equal to or greater than the first predetermined temperature difference ΔTT1, the control device 9 uses the first switching valve 7 to connect the vaporizer 3 to the first underground piping, and circulates hot water in the order of the heat source device 4, the vaporizer 3, the underground, and the heat source device 4.

[0057] Next, the control device 9 determines whether the outside air underground temperature difference ΔT1 is equal to or greater than ΔTT2 (S114), where ΔTT2 is a temperature lower than ΔTT1, and is, for example, 0.5° C. in this modified example.

[0058] Next, when the controller 9 determines that the outside air / ground temperature difference ΔT1 is equal to or greater than ΔTT2 (S112=YES), it maintains the piping pattern B (S113).

[0059] In addition, the control device 9 selects piping pattern A (S115) when it determines that the outside air temperature T2 is not equal to or higher than TT3 (S110=NO), determines that the vaporizer is not operating (S111=NO), determines that the outside air underground temperature difference ΔT1 is not equal to or higher than ΔTT1 (S112=NO), or determines that the outside air underground temperature difference ΔT1 is not equal to or higher than ΔTT2 (S114=NO). Here, when any of the following conditions are met, the control device 9 connects the vaporizer 3 to the second normal piping using the first switching valve 7, and circulates the hot water in the order of the heat source unit 4, the vaporizer 3, and the heat source unit 4: the outside air temperature T2 is less than TT3, the heat source unit 4 is not operating, i.e., the hot water returned to the heat source unit 4 is not being heated, the outside air underground temperature difference ΔT1 is not equal to or greater than ΔTT1, i.e., the underground temperature T3 is not high enough to heat the hot water relative to the outside air temperature T2, or the outside air underground temperature difference ΔT1 is not ΔTT2, i.e., the underground temperature T3 cannot heat the hot water relative to the outside air temperature T2.

[0060] According to this modification, the temperature of the hot water returning to the heat source unit 4 can be increased by geothermal heat, so that the amount of heat applied to the hot water by the heat source unit 4 can be reduced. Therefore, it becomes possible to use geothermal heat as a heat source for heating the vaporizer.

[0061] In this modification, hot water may be supplied from the heat source unit 4 to the vaporizer 3 by the piping pattern B if the outside air underground temperature difference ΔT1 is equal to or smaller than ΔTT1 and the vaporizer 3 is in an operating state.

[0062] [Second embodiment] Next, a second embodiment of the present invention will be described. Fig. 4 is a configuration diagram of a vaporizer system 1 in the second embodiment. In the configuration described in the first embodiment, the description of the same reference numerals will be omitted.

[0063] The vaporizer system 1 in the second embodiment includes a bulk storage tank 2, a vaporizer 3, a heat source unit 4, a liquid gas supply unit 5, a vaporized gas supply unit 6, a first pressure switch PSW1, a second pressure switch PSW2, a first switching valve 7, a second switching valve 8, a first temperature sensor TH1, a second temperature sensor TH2, a third temperature sensor TH3, a first pipe R1 to an eleventh pipe R11, a snowfall sensor (not shown), and a control device 9.

[0064] The second pipe R2 is connected to the second switching valve 8 at one end and to the hot water inlet 31a at the other end.

[0065] The tenth pipe R10 is connected to the heat source unit 4 at one end and to the second switching valve 8 at the other end.

[0066] The eleventh pipe R11 is connected to the second switching valve 8 at one end and to the second pipe R2 at the other end. A part of the eleventh pipe R11 passes underground. The eleventh pipe R11 usually serves to introduce the hot water introduced from the heat source unit 4 to the vaporizer 3 into the ground and transfer the heat of the hot water into the ground.

[0067] Here, in the second embodiment, the first normal piping is composed of the tenth pipe R10 and the second pipe R2, the second normal piping is composed of the third pipe R3, the fifth pipe R5 and the sixth pipe R6, the first underground piping is composed of the third pipe R3, the ninth pipe R9 and the sixth pipe R6, and the second underground piping is composed of the tenth pipe R10, the eleventh pipe R11 and the second pipe R2.

[0068] The second switching valve 8 is connected to the second pipe R2, the tenth pipe R10, and the eleventh pipe R11. The second switching valve 8 switches between communication between the tenth pipe R10 and the second pipe R2 and communication between the tenth pipe R10 and the eleventh pipe R11. That is, the second switching valve 8 switches between communication between the heat source unit 4 and the first normal pipe and communication between the heat source unit 4 and the second underground pipe. The second switching valve 8 is electrically connected to the control device 9, and the control device 9 controls the switching.

[0069] The control device 9 controls the switching of the first switching valve 7 and the second switching valve 8 according to the second normal piping temperature T1, the outside air temperature T2, and the underground temperature T3, which are the measurement results of the temperature sensors TH1 to TH3, i.e., switches between normal control and snowfall control. Specifically, the first switching valve 7 and the second switching valve 8 switch between piping pattern A, piping pattern B, piping pattern C, and piping pattern D.

[0070] Here, the piping pattern A in the second embodiment is a route that passes through the tenth pipe R10 and the second pipe R2, i.e., the first normal pipe, which directly supply hot water from the heat source unit 4 to the vaporizer 3, and the third pipe R3, the fifth pipe R5 and the sixth pipe R6, i.e., the second normal pipe, which directly return the hot water discharged from the vaporizer 3 to the heat source unit 4.

[0071] In addition, piping pattern B in the second embodiment is a route that passes through the tenth pipe R10 and the second pipe R2, which directly supply hot water from the heat source unit 4 to the vaporizer 3, and the third pipe R3, the ninth pipe R9 and the sixth pipe R6, i.e., the first underground pipe, which returns the hot water discharged from the vaporizer 3 to the heat source unit 4 via the ground.

[0072] In addition, the piping pattern C in the second embodiment is a route that passes through the tenth pipe R10, the eleventh pipe R11, and the second pipe R2, i.e., the second underground pipe, which supplies hot water supplied from the heat source unit 4 to the vaporizer 3 via the ground, and through the third pipe R3, the fifth pipe R5, and the sixth pipe R6, i.e., the second normal pipe, which returns the hot water discharged from the vaporizer 3 directly to the heat source unit 4.

[0073] In addition, piping pattern D in the second embodiment is a route that passes through the tenth pipe R10, the eleventh pipe R11, and the second pipe R2, i.e., the second underground pipe, which supplies hot water supplied from the heat source unit 4 to the vaporizer 3 via the ground, and the third pipe R3, the ninth pipe R9, and the sixth pipe R6, i.e., the first underground pipe, which returns hot water discharged from the vaporizer 3 to the heat source unit 4 via the ground.

[0074] Next, a description will be given of the operation of the vaporizer system 1 in the second embodiment. Fig. 5 is a diagram showing a control flow of the vaporizer system 1 in the second embodiment.

[0075] First, as shown in FIG. 5, the control device 9 determines whether or not snow removal is necessary (S201).

[0076] Next, when the control device 9 determines that snow removal is necessary (S201=YES), it determines whether or not the vaporizer 3 is operating (S202).

[0077] Next, when the control device 9 determines that the vaporizer 3 is operating (S202=YES), it determines whether the second normal pipe temperature T1 is equal to or higher than TT4 (S203). Here, TT4 is a second predetermined temperature, which is, for example, 65° C. in the second embodiment.

[0078] Next, when the control device 9 determines that the second normal piping temperature T1 is equal to or higher than TT4 (S203=YES), it selects piping pattern D (S204). Here, when the second normal piping temperature T1 is equal to or higher than the second predetermined temperature TT4, the control device 9 uses the first switching valve 7 to connect the vaporizer 3 to the first underground piping, and uses the second switching valve 8 to connect the heat source unit 4 to the second underground piping, and circulates hot water in the order of the heat source unit 4, underground, the vaporizer 3, underground, and the heat source unit 4.

[0079] Next, when the control device 9 determines that the second normal piping temperature T1 is not equal to or higher than TT4 (S203=NO), it determines whether the second normal piping temperature T1 is equal to or higher than TT5 (S205). Here, TT5 is a third predetermined temperature, which is lower than TT4, and is, for example, 60° C. in the second embodiment.

[0080] Next, when the control device 9 determines that the second normal piping temperature T1 is equal to or higher than TT5 (S205=YES), it selects piping pattern C (S206). Here, when the second normal piping temperature T1 is equal to or higher than the third predetermined temperature TT5, the control device 9 uses the first switching valve 7 to connect the vaporizer 3 to the second normal piping, and uses the second switching valve 8 to connect the heat source unit 4 to the second underground piping, and circulates hot water in the order of the heat source unit 4, underground, vaporizer 3, and heat source unit 4.

[0081] Next, when the control device 9 determines that the second normal piping temperature T1 is not equal to or higher than TT5 (S205=NO), it determines whether the second normal piping temperature T1 is equal to or higher than TT6 (S207). Here, TT6 is a fourth predetermined temperature, which is lower than TT5, and is, for example, 55° C. in the second embodiment.

[0082] Next, when the control device 9 determines that the second normal piping temperature T1 is equal to or higher than TT6 (S207=YES), it selects piping pattern B (S208). Here, when the second normal piping temperature T1 is equal to or higher than the fourth predetermined temperature TT6, the control device 9 uses the first switching valve 7 to connect the vaporizer 3 to the first underground piping, and uses the second switching valve 8 to connect the heat source unit 4 to the first normal piping, and circulates hot water in the order of the heat source unit 4, the vaporizer 3, the ground, and the heat source unit 4.

[0083] Furthermore, when the control device 9 determines that snow removal is not necessary (S201=NO), determines that the vaporizer is not operating (S202=NO), or determines that the second normal piping temperature T1 is not equal to or higher than TT6 (S207=NO), it selects piping pattern A (S209). Here, when the control device 9 determines that snow removal is not necessary, that the heat source device 4 is not operating, i.e., the hot water returned to the heat source device 4 is not being heated, or the second normal piping temperature T1 is not equal to or higher than the first predetermined temperature TT6, it uses the first switching valve 7 to connect the vaporizer 3 to the second normal piping, and the second switching valve 8 to connect the heat source device 4 to the first normal piping, and circulates the hot water in the order of the heat source device 4, the vaporizer 3, and the heat source device 4.

[0084] According to this embodiment, the hot water returning from the vaporizer 3 to the heat source unit 4, i.e., hot water at a higher temperature than the temperature around the underground pipes, is passed through underground pipes buried underground corresponding to the road surface that needs snow removal, thereby raising the temperature of the road surface and making it possible to use it for road heating. Furthermore, by switching the pipes through which the hot water flows according to changes in the hot water temperature, the road heating capacity can be switched in stages.

[0085] [Modification of the second embodiment] Next, another operation of the vaporizer system 1 in the second embodiment will be described. Fig. 6 is a diagram showing a control flow of the vaporizer system in a modified example of the second embodiment. Note that this modified example is premised on the fact that it is executed when there is no snowfall, such as in summer, i.e., when no snowfall is detected by a snowfall sensor (not shown).

[0086] First, the control device 9 judges whether the outside air temperature T2 is equal to or higher than TT7 (S210). Here, TT7 is, for example, 5° C. in this modified example.

[0087] Next, when the controller 9 determines that the outside air temperature T2 is equal to or higher than TT7 (S210=YES), the controller 9 determines whether or not the vaporizer 3 is operating (S211).

[0088] Next, when the control device 9 determines that the vaporizer 3 is operating (S211=YES), it determines whether the outside air underground temperature difference ΔT1 (=T3-T2), which is the temperature difference between the underground temperature T3 and the outside air temperature T2, is equal to or greater than ΔTT3 (S212). Here, ΔTT3 is a second predetermined temperature difference, which is, for example, 2°C in this modified example.

[0089] Next, when the control device 9 determines that the outside air underground temperature difference ΔT1 is equal to or greater than ΔTT3 (S212=YES), it selects piping pattern B (S213). Here, when the outside air underground temperature difference ΔT1 is equal to or greater than the second predetermined temperature difference ΔTT3, the control device 9 uses the first switching valve 7 to connect the vaporizer 3 to the first underground piping, and circulates hot water in the order of the heat source device 4, the vaporizer 3, the underground, and the heat source device 4.

[0090] Next, the control device 9 judges whether the outside air underground temperature difference ΔT1 is equal to or greater than ΔTT4 (S214). Here, ΔTT4 is a temperature lower than ΔTT3, and in this modified example, is, for example, 0.5°C.

[0091] Next, when the controller 9 determines that the outside air underground temperature difference ΔT1 is equal to or greater than ΔTT4 (S214=YES), it maintains the piping pattern B (S213).

[0092] In addition, the control device 9 selects piping pattern A (S215) when it determines that the outside air temperature T2 is not equal to or greater than TT3 (S210=NO), determines that the vaporizer is not operating (S211=NO), determines that the outside air underground temperature difference ΔT1 is not equal to or greater than ΔTT3 (S212=NO), or determines that the outside air underground temperature difference ΔT1 is not equal to or greater than ΔTT4 (S214=NO). Here, when any of the following conditions are met, the control device 9 connects the vaporizer 3 to the second normal piping using the first switching valve 7, and circulates the hot water in the order of the heat source unit 4, the vaporizer 3, and the heat source unit 4: the outside air temperature T2 is less than TT3, the heat source unit 4 is not operating, i.e., the hot water returned to the heat source unit 4 is not being heated, the outside air underground temperature difference ΔT1 is not equal to or greater than ΔTT3, i.e., the underground temperature T3 is not high enough to heat the hot water relative to the outside air temperature T2, or the outside air underground temperature difference ΔT1 is not ΔTT4, i.e., the underground temperature T3 is not high enough to heat the hot water relative to the outside air temperature T2.

[0093] According to this modification, the temperature of the hot water returning to the heat source unit 4 can be increased by geothermal heat, so that the amount of heat applied to the hot water by the heat source unit 4 can be reduced. Therefore, it becomes possible to use geothermal heat as a heat source for heating the vaporizer.

[0094] [Third embodiment] Next, a third embodiment of the present invention will be described. Fig. 7 is a configuration diagram of a vaporizer system 1 in the third embodiment. In the configurations described in the first and second embodiments, the explanation of the same reference numerals will be omitted.

[0095] The vaporizer system 1 in the third embodiment includes a bulk storage tank 2, a vaporizer 3, a heat source unit 4, a liquid gas supply unit 5, a vaporized gas supply unit 6, a first pressure switch PSW1, a second pressure switch PSW2, a first switching valve 7, a second switching valve 8, a third switching valve 10, a first opening / closing valve 11, a second opening / closing valve 12, a first temperature sensor TH1, a second temperature sensor TH2, a third temperature sensor TH3, a first pipe R1 to a thirteenth pipe R13, a snowfall sensor (not shown), and a control device 9.

[0096] The ninth pipe R9 has one end connected to the third pipe R3 and the fifth pipe R5 at a junction A which is a connection portion, and the other end connected to the third switching valve 10.

[0097] The twelfth pipe R12 is a first bypass pipe, one end of which is connected to the third switching valve 10, and the other end of which is connected to the section of the eleventh pipe R11 between the ground and the second pipe R2.

[0098] The 13th pipe R13 is a second bypass pipe, one end of which is connected to the 11th pipe R11 between the second switching valve 8 and the ground, and the other end of which is connected to the 9th pipe R9 between the third switching valve 10 and the second opening / closing valve 12, with the entire pipe being installed above ground.

[0099] The third switching valve 10 is provided in the middle of the ninth pipe R9 and connected to the twelfth pipe R12. The third switching valve 10 switches between the communication between the ninth pipe R9 connected to the contact A and the twelfth pipe R12, and between the ninth pipe R9 connected to the contact A and the ninth pipe R9 connected to the first switching valve 7. That is, the tenth switching valve 10 switches between the communication between the first underground pipe and the heat source unit 4, and the communication between the first underground pipe 4 and the vaporizer 3. The third switching valve 10 is electrically connected to the control device 9, and the control device 9 performs switching control.

[0100] The first on-off valve 11 is provided in the thirteenth pipe R13 and is electrically connected to the control device 9, and its opening and closing is controlled by the control device 9. The first on-off valve 11 is closed in normal control.

[0101] The second on-off valve 12 is provided in the eleventh pipe R11 and is electrically connected to the control device 9, and its opening and closing is controlled by the control device 9. The second on-off valve 12 is kept open in normal control.

[0102] The control device 9 controls the switching of the first switching valve 7, the second switching valve 8, and the third switching valve 10 according to the second normal piping temperature T1, the outside air temperature T2, and the underground temperature T3, which are the measurement results of the temperature sensors TH1 to TH3, i.e., switches between normal control and snowfall control. Specifically, the first switching valve 7, the second switching valve 8, and the third switching valve 10 switch between piping pattern A, piping pattern B, piping pattern C, piping pattern D, piping pattern E, and piping pattern F.

[0103] Here, the piping pattern A in the third embodiment is a route that passes through the tenth pipe R10 and the second pipe R2, i.e., the first normal pipe, which directly supply hot water from the heat source unit 4 to the vaporizer 3, and the third pipe R3, the fifth pipe R5 and the sixth pipe R6, i.e., the second normal pipe, which directly return the hot water discharged from the vaporizer 3 to the heat source unit 4.

[0104] In addition, piping pattern B in the third embodiment is a route that passes through the tenth pipe R10 and the second pipe R2, which directly supply hot water from the heat source unit 4 to the vaporizer 3, and the third pipe R3, the ninth pipe R9 and the sixth pipe R6, i.e., the first underground pipe, which returns the hot water discharged from the vaporizer 3 to the heat source unit 4 via the ground.

[0105] In addition, piping pattern C in the third embodiment is a route that passes through the third pipe R3, the ninth pipe R9, the twelfth pipe R12, the eleventh pipe R11, the thirteenth pipe R13, the ninth pipe R9, and the sixth pipe R6, i.e., the first underground pipe and the second underground pipe, by opening the first on-off valve 11 and closing the second on-off valve 12, and returning the hot water discharged from the vaporizer 3 to the heat source unit 4 twice through the ground.

[0106] In addition, the piping pattern D in the third embodiment is a route that passes through the tenth pipe R10, the eleventh pipe R11, and the second pipe R2, i.e., the second underground pipe, which supplies hot water supplied from the heat source unit 4 to the vaporizer 3 via the ground, and through the third pipe R3, the fifth pipe R5, and the sixth pipe R6, i.e., the second normal pipe, which returns the hot water discharged from the vaporizer 3 directly to the heat source unit 4.

[0107] In addition, the piping pattern E in the third embodiment is a route that passes through the tenth pipe R10, the eleventh pipe R11, and the second pipe R2 to supply hot water from the heat source unit 4 to the vaporizer 3 via the ground, and passes through the third pipe R3, the ninth pipe R9, and the sixth pipe R6 to return the hot water discharged from the vaporizer 3 to the heat source unit 4 via the ground.

[0108] In addition, the piping pattern F in the third embodiment is a route that passes through the tenth pipe R10, the eleventh pipe R11, the twelfth pipe R12, the ninth pipe R9, the fifth pipe R5 and the sixth pipe R6, i.e., the second underground pipe and the first underground pipe, in which the hot water supplied from the heat source unit 4 is returned to the heat source unit 4 by passing underground twice by opening the first opening / closing valve 11 and closing the second opening / closing valve.

[0109] Next, the operation of the vaporizer system 1 in the third embodiment will be described. The control device 9 determines that snow removal is necessary, determines that the vaporizer 3 is operating, and determines that the second normal pipe temperature T1 is TT8 or higher, and selects piping pattern F. When the control device 9 determines that the second normal pipe temperature T1 is TT9 or higher, which is a temperature lower than TT8, the control device selects piping pattern E. When the control device 9 determines that the second normal pipe temperature T1 is TT10 or higher, which is a temperature lower than TT9, the control device selects piping pattern D. When the control device 9 determines that the second normal pipe temperature T1 is TT11 or higher, which is a temperature lower than TT10, the control device selects piping pattern C. When the control device 9 determines that the second normal pipe temperature T1 is TT12 or higher, which is a temperature lower than TT11, the control device selects piping pattern B.

[0110] Moreover, the control device 9 selects the piping pattern A when it determines that snow removal is not necessary, that the vaporizer is not operating, or that the second normal piping temperature T1 is not equal to or higher than TT12.

[0111] According to this embodiment, hot water returning from the vaporizer 3 to the heat source unit 4, i.e., hot water at a higher temperature than the temperature around the underground pipe, is passed through underground pipes buried in the ground corresponding to the road surface that needs snow removal, thereby raising the temperature of the road surface and making it possible to use it for road heating. Furthermore, by switching the pipes through which the hot water flows according to changes in the hot water temperature, the road heating capacity can be switched in stages. Also, by using the piping pattern F, there is no heat dissipation from the vaporizer 3 to the hot water from the heat source unit 4, making it possible to increase the snow removal capacity.

[0112] In the third embodiment, similarly to the first and second embodiments, control may be performed to increase the temperature of the hot water returning to the heat source unit 4 using geothermal heat.

[0113] In the first and second embodiments, the first and second normal pipes do not necessarily need to pass through the vaporizer 3. For example, a bypass pipe may be provided between the first and second normal pipes. This prevents heat from being dissipated to the vaporizer, and improves snow removal performance.

[0114] In all embodiments of the present invention, the vaporizer 3 introduces LP gas that has naturally vaporized due to the ambient temperature into the vaporized gas supply unit 6 via the seventh piping R7, but this is not limited to this, and the vaporizer may be one that does not use the seventh piping R7 and does not introduce naturally vaporized LP gas into the vaporized gas supply unit 6.

[0115] In all the embodiments of the present invention, the heat exchanger 32 of the vaporizer 3 is provided in a coil shape, but this is not limited thereto, and it may be a plate type heat exchanger. [Explanation of symbols]

[0116] 1 Vaporizer System 3 Vaporizer 4 Heat source machine 7 First switching valve 8. Second switching valve 9. Control Device 10. Third switching valve TH1 First temperature sensor TH2 Second temperature sensor TH3 3rd temperature sensor T1 2nd normal pipe temperature T2 Outside temperature T3 underground temperature ΔT1 Outside air underground temperature difference TT1 1st predetermined temperature TT4 2nd predetermined temperature TT5 3rd predetermined temperature TT6 4th predetermined temperature ΔTT1 First predetermined temperature difference ΔTT3 Second predetermined temperature difference

Claims

1. A gas container for storing liquid fuel gas; a vaporizer that introduces the liquid fuel gas from the gas container and vaporizes it by heating; A heat source device that heats liquid fuel gas; A first normal pipe that directly supplies a medium from the heat source unit to the vaporizer; A second normal pipe that directly returns the medium discharged from the vaporizer to the heat source unit; A first underground pipe that returns the medium discharged from the vaporizer to the heat source device and has a portion thereof passing underground; a first switching valve that switches communication between the vaporizer and the second normal pipe and communication between the vaporizer and the first underground pipe; A first temperature sensor that measures a second normal pipe temperature, which is the temperature of the second normal pipe; a control device that controls the first switching valve in response to the second normal piping temperature; Equipped with The control device includes: A vaporizer system characterized in that, when the second normal piping temperature is equal to or higher than a first predetermined temperature, the first switching valve switches from communication between the vaporizer and the second normal piping to communication between the vaporizer and the first underground piping.

2. A gas container for storing liquid fuel gas; a vaporizer that introduces the liquid fuel gas from the gas container and vaporizes it by heating; A heat source device that heats liquid fuel gas; A first normal pipe that directly supplies a medium from the heat source unit to the vaporizer; A second normal pipe that directly returns the medium discharged from the vaporizer to the heat source unit; A first underground pipe that returns the medium discharged from the vaporizer to the heat source device and has a portion thereof passing underground; a first switching valve that switches communication between the vaporizer and the second normal pipe and communication between the vaporizer and the first underground pipe; A second temperature sensor for measuring an outside air temperature; A third temperature sensor for measuring a ground temperature; a control device that controls the first switching valve in response to an outside air / ground temperature difference between the outside air temperature and the ground temperature; Equipped with The control device includes: A vaporizer system characterized in that, when the outside air underground temperature difference is equal to or greater than a first predetermined temperature difference, the first switching valve switches from communication between the vaporizer and the second normal piping to communication between the vaporizer and the first underground piping.

3. A gas container for storing liquid fuel gas; a vaporizer that introduces the liquid fuel gas from the gas container and vaporizes it by heating; A heat source device that heats liquid fuel gas; A first normal pipe that directly supplies a medium from the heat source unit to the vaporizer; A second normal pipe that directly returns the medium discharged from the vaporizer to the heat source unit; A first underground pipe that returns the medium discharged from the vaporizer to the heat source device and has a portion thereof passing underground; A second underground pipe that supplies a medium from the heat source device to the vaporizer and has a portion thereof passing underground; a first switching valve that switches communication between the vaporizer and the second normal pipe and communication between the vaporizer and the first underground pipe; A second switching valve that switches communication between the heat source unit and the first normal piping and communication between the heat source unit and the second underground piping; A first temperature sensor that measures a second normal pipe temperature, which is the temperature of the second normal pipe; a control device that controls the first switching valve and the second switching valve in response to the second normal piping temperature; Equipped with The control device includes: When the second normal piping temperature is equal to or higher than a second predetermined temperature, The first switching valve switches from communication between the vaporizer and the second normal piping to communication between the vaporizer and the first underground piping, and the second switching valve switches from communication between the heat source unit and the first normal piping to communication between the heat source unit and the second underground piping, When the second normal piping temperature is equal to or higher than a third predetermined temperature which is lower than the second predetermined temperature, The second switching valve switches from communication between the heat source unit and the first normal piping to communication between the heat source unit and the second underground piping, When the second normal piping temperature is equal to or higher than a fourth predetermined temperature which is lower than the third predetermined temperature, The first switching valve switches from communication between the vaporizer and the second normal pipe to communication between the vaporizer and the first underground pipe. A vaporizer system comprising:

4. A gas container for storing liquid fuel gas; a vaporizer that introduces the liquid fuel gas from the gas container and vaporizes it by heating; A heat source device that heats liquid fuel gas; A first normal pipe that directly supplies a medium from the heat source unit to the vaporizer; A second normal pipe that directly returns the medium discharged from the vaporizer to the heat source unit; A first underground pipe that returns the medium discharged from the vaporizer to the heat source device and has a portion thereof passing underground; A second underground pipe that supplies a medium from the heat source device to the vaporizer and has a portion thereof passing underground; a first switching valve that switches communication between the vaporizer and the second normal pipe and communication between the vaporizer and the first underground pipe; A second switching valve that switches communication between the heat source unit and the first normal piping and communication between the heat source unit and the second underground piping; A second temperature sensor for measuring an outside air temperature; A third temperature sensor for measuring a ground temperature; a control device that controls the first changeover valve and the second changeover valve in response to an outside air / ground temperature difference between the outside air temperature and the ground temperature; Equipped with The control device includes: When the outside air underground temperature difference is equal to or greater than a second predetermined temperature difference, A vaporizer system, characterized in that the first switching valve switches communication between the vaporizer and the second normal piping to communication between the vaporizer and the first underground piping.

Images