JP2006266365A - Liquefied gas transferring and filling system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system capable of suppressing cost of facility as much as possible, facilitating maintenance and management, and transferring and filling liquefied gas (liquid) stably. <P>SOLUTION: This liquefied gas transferring and filling system is provided with a storage tank device 1 incorporating a siphone tube as a liquid taking-out tube, liquefied gas heating devices 2, 3, and two machines of heat source corresponding to them. Operation of only the liquefied gas heating device on one side being in a fully filled condition among each heat source is controlled, each gaseous phase line connected with the storage tank device of both of liquefied gas heating devices 2, 3 and each liquid feeding line connected with a transferring and filling destination device are alternately opened, closed, and controlled, and a liquid receiving line connected with each liquefied gas heating device through a taking-out valve from the storage tank device in the interlocking relationship with the opening, closing, and controlling of each line so as to switch is provided. A part of liquefied gas liquid in a pressurized condition of the liquefied gas heating device on one side being in a fully filled condition is applied to the liquid receiving line. A venturi tube 7 for absorbing liquefied gas liquid at lower level than the taking-out valve from the siphone tube by negative pressure generated at this time and supplying it to the liquefied gas heating device on the other side is provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a series of systems for transferring liquefied gas liquid stored in a bulk storage tank to a liquefied gas vehicle using liquefied gas as fuel. A series of systems for transferring and filling liquefied gas liquid from a tank truck to the bulk storage tank is also disclosed.

  Currently, the spread of liquefied gas vehicles is desired for the purpose of saving oil resources and preserving the global environment. It is a well-known fact that in the implementation of this technology, it is important not only to develop a liquefied gas vehicle but also to establish a technology for its fuel supply method, that is, a liquefied gas stand system.

  Therefore, when explaining a conventional example of the system, there are roughly two liquefied gas transfer and filling systems. First, the first is a method of transferring a liquefied gas in a bulk storage tank to a dispenser in a liquid state (liquefied gas liquid) using a liquid feed pump using electricity as a power source. Second, in addition to the bulk storage tank of butane gas (liquid) serving as fuel, a bulk storage tank of propane vaporized gas, nitrogen or natural gas (CNG) (hereinafter simply referred to as propane vaporized gas, etc.) is provided. The bulk tank of butane gas (liquid) is pressurized by the vaporization pressure of propane vaporized gas and the like, and the structure of transferring the butane gas (liquid) to the dispenser is adopted.

  Next, problems of the conventional system will be described. First, in the first system, vapor is generated unless NPSH (Net Positive Suction Head / suction head) is secured between the storage tank and the liquid feed pump, and transfer and filling cannot be performed smoothly. There was a connected problem. In order to avoid this problem, the installation height of the liquefied gas storage tank needs to be considerably high, but if this is the case, it will be necessary to take strong measures against earthquakes. Problems arise. In addition, an electrically driven liquid feed pump requires a high-voltage power supply of 200 V or more, and the pump falls under the High-Pressure Gas Safety Law, and corresponds to a treatment facility. It is no exaggeration to say that various legal obligations, such as resident residence, have caused the spread of the liquefied gas stand system.

  On the other hand, in the second system, a bulk storage tank of propane vaporized gas or the like for obtaining a transfer pressure is required separately from the butane bulk storage tank that serves as fuel, and at least two storage tanks are required. For this reason, it is necessary to secure a large installation area for the installation of the system. In particular, in this system, propane vaporized gas or the like is mixed into the butane side, which may lead to a decrease in the combustion rate of the car engine. Therefore, in order to keep the butane component constant, a butane gas (liquid) storage tank for supplemental filling is used. In this case, the problem that the installation area is further enlarged and the equipment cost is expensive is further promoted. In addition, since this system employs a method of vaporizing propane, etc., depending on the outside temperature, the vaporization pressure of propane, etc., and the amount of butane transferred, which is easily affected by changes in the outside temperature, is stable. There is also a problem that it is difficult to do.

  The present invention has been made to solve the above-mentioned problems of the prior art, and the object of the present invention is to suppress equipment costs as much as possible, facilitate safety management, and stably transfer liquefied gas (liquid). A system that can be filled is disclosed.

  In order to achieve the above-described object, the present invention stores the liquefied gas in a liquid state and takes out the liquefied gas liquid from the valve through the siphon tube raised from the inner bottom and supplies the liquefied gas liquid with water head pressure or / and dead weight. A predetermined amount of liquefied gas liquid is supplied from the storage apparatus through the take-off valve, and then the supplied liquefied gas liquid can be delivered by pressurizing the gas phase portion in a sealed state. A liquefied gas heater, a heat source for pressurizing the gas phase portion of the liquefied gas heater by heating the liquefied gas liquid in the liquefied gas heater and generating a vapor pressure, and a liquefied gas heater The liquefied gas warmer and two heat sources corresponding to the liquefied gas warmer and the corresponding liquefied gas warming of each heat source Control only the machine side and both Each vapor line connected to the storage tank device of the chemical gas heater and each liquid delivery line connected to the transfer-filling destination device are alternately controlled to open and close, and further, taken out from the storage device in conjunction with the open / close control. A liquid receiving line that is switchably connected to each liquefied gas heater via a valve is provided, and the liquefied gas liquid in the pressurized state of one liquefied gas warmer that is fully filled in the liquid receiving line is provided. It is said that a Venturi tube is interposed through which a part of the liquefied gas liquid is applied to the other liquefied gas warmer by sucking the liquefied gas liquid at a level lower than that of the take-off valve by the negative pressure generated at this time from the siphon pipe. Means were used.

  According to a second aspect of the present invention, the injection pressure of the liquefied gas liquid is applied to the venturi tube from one liquefied gas warmer, and the other liquefied gas warmer is supplied from the storage tank device by its injection amount and negative pressure. A means of supplying a liquefied gas liquid in which the total amount of suction is added is adopted.

  According to a third aspect of the present invention, each liquefied gas warmer is provided with a level gauge for detecting a level signal of the liquefied gas liquid, and the liquid receiving line is switched and controlled when the liquefied gas warmer is fully filled with the level signal. Is used.

  In claim 4, the heat source is warm water, and in claim 5, the storage tank apparatus is a bulk storage tank of liquefied gas liquid, and the transfer and filling destination apparatus is a liquefied gas vehicle via a dispenser.

  As described above, according to the present invention, in a storage tank apparatus incorporating a siphon tube as a liquid discharge tube, a liquefied gas liquid at a level below the liquid discharge valve that could not be extracted by dropping only by water head pressure or its own weight is conventionally used. Can also be supplied to the liquefied gas heater. Further, since no liquid feed pump is used, no vapor is generated and no power source is required, so that the equipment cost for system construction can be greatly reduced. In addition, there is no legal obligation such as resident security personnel due to the structure, which contributes to the spread of this kind of system. In addition, since a bulk storage tank for propane is not required, the storage tank only needs a liquefied gas liquid, and the equipment cost can be reduced as the installation area is reduced. Further, since propane is not required at all, impurities are not mixed in butane which is a liquefied gas liquid fuel, and an inadvertent reduction in the combustion rate is avoided. Furthermore, since the forced heating means by the heater is provided, the liquefied gas liquid can be stably supplied without being influenced by the outside air temperature.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a circuit diagram of a liquefied gas transfer and filling system according to an embodiment of the present invention, which is applied to an auto gas stand that supplies liquefied gas (liquid) to a liquefied gas vehicle. In the figure, 1 is a bulk storage tank that stores liquefied gas (liquid), 2 and 3 are liquefied gas received from the bulk storage tank 1 in a liquid state, and further pressurized to supply the liquefied gas (liquid) to a later-described dispenser 13. A liquefied gas heater 3 is used to fill a liquefied gas vehicle with a liquefied gas (liquid) through a nozzle or the like, and is a liquefied gas (liquid) dispenser having almost the same function as a dispenser in a conventional gas station. . Reference numeral 4 denotes a heat source device, which is configured to generate hot water and to circulate this hot water to the heaters 5 and 6 that are operated exclusively by the three-way switching valves 4a and 4b. The heaters 5 and 6 communicate with the liquefied gas heaters 2 and 3, and the liquefied gas is heated by heating the liquefied gas (liquid) with hot water in the heat exchangers 5 'and 6' provided therein. The gas phase portion in the vessels 2 and 3 is pressurized, and the liquefied gas (liquid) is fed from the liquefied gas heaters 2 and 3 to the dispenser 13.

  The connection between the respective parts will be described in detail. First, in this embodiment, the bulk storage tank 1 stores about 1 t of liquefied gas (liquid), and inside thereof, as shown in FIG. A siphon tube 1a rising to the vicinity of the center is provided, and the liquefied gas liquid is supplied to the liquefied gas heaters 2 and 3 from the liquid take-off valve 1b via the siphon tube 1a. The liquefied gas (liquid) in the bulk storage tank 1 is supplied to the liquefied gas heaters 2 and 3 by the head pressure and its own weight, and also liquefied by negative pressure suction generated in a Venturi tube 7 provided in the liquid receiving line described later. It supplies to gas heater 2 * 3.

  In FIG. 1, 8 is a gas phase line, 9 is a liquid delivery line, 10 is a liquid receiving line, and the liquid receiving line 10 is a first line 10a connecting the liquefied gas heaters 2 and 3, and A second line 10b connecting the bulk storage tank 1 and the first line 10a, and a second line 10b for applying the injection pressures of the liquefied gas heaters 2 and 3 to the venturi tube 7 provided in the middle of the second line 10b. It consists of three lines 10c. The first and second lines 10a and 10c of the gas phase line 8, the liquid delivery line 9 and the liquid receiving line 10 have automatic valves VA1 to VA4 and automatic valves for determining the flow of the gas phase and the liquid in one direction. VB1 to VB4 are provided. That is, with this circuit configuration, the liquefied gas liquid can be sent from one liquefied gas warmer to the dispenser 13 and filled in the other liquefied gas warmer in parallel with this, as will be described later. is there. The liquefied gas heaters 2 and 3 are provided with liquid level gauges 11 and 12 to detect the liquid level of the liquefied gas heaters 2 and 3.

The operation of the auto gas stand type liquefied gas transfer and filling system having the above configuration will be described. Now, one of the two liquefied gas heaters 2 and 3 has the liquefied gas liquid at the Hi level, It is assumed that the other heater 3 is at the Lo level. This state is manually realized during the initial operation. In this embodiment, the storage amount display of each of the liquefied gas heaters 2 and 3 is Hi level when l ₁ + l ₂ + l ₃ , and l ₁ is Lo level. For example, the efficiency of the venturi tube 7 is set such that the ratio of the injection amount from the heaters 2 and 3 to the supply amount from the bulk storage tank 1 is 2: 1, for example.

Subsequently, among the automatic valves, VA1, VA3, VB2, and VB4 are closed, and VA2, VA4, VB1, and VB3 are opened, and one heater 2 on the left side of the drawing is used for filling and the other is heated. The gas phase and liquid phase line are secured for receiving the vessel 3. Next, the heat source device 4 is operated, and the three-way switching valves 4a and 4b are operated to circulate the hot water from the heat source device 4 to the heater 5 corresponding to the heating heater 2 for filling. By these operations, the liquefied gas liquid in the heater 2 is heated by the heat exchanger 5 ′ in the heater 5, and the liquefied gas liquid is heated by the vapor pressure of the liquefied gas liquid through the valve-opened VA 2. The liquid is delivered from the liquid delivery line 9 to the dispenser 13 through the lines 10c and VA4. At this time, l _{3 of the} liquefied gas liquid supplied from the heater 2 is distributed to the liquid delivery line 9 side, and l ₁ + l ₂ is distributed to the third line 10c by the differential pressure effect generated in the venturi tube 7. That is, in this configuration, while the liquefied gas liquid is sent from one of the heaters 2 to the dispenser 13, at the same time, an injection amount of l ₁ + l ₂ is applied to the venturi pipe 7. A negative pressure is generated, and by this negative pressure, the liquefied gas liquid for 13 minutes from the bulk storage tank 1 is sucked through the siphon tube 1a, and merged with the injection l ₁ + l ₂ in the second line 10b. The total amount of the liquefied gas liquid can be filled in the other heater 3. After that, the automatic valve and the three-way switching are detected by detecting that the empty warmer 3 that has been used for receiving until the sum of l ₁ + l ₂ + l ₃ is filled with the liquid level gauge 12. Each valve is actuated to the proper state and the next standby is completed. That is, when the vehicle is completely filled with the liquefied gas liquid and the switch of the dispenser 13 is turned off, the automatic valve VA4 is closed and the hot water three-way valves 4a and 4b are also operated to circulate the hot water to the heaters 5 and 6. stop. Then, when filling the next vehicle, the dispenser 13 is turned on, and the supply and reception modes of the heaters 2 and 3 are switched by switching to the open / closed state of the automatic valve and the hot water three-way valve contrary to the above. .

  In the above-described embodiment, the liquefied gas heaters 2 and 3 are vertical. However, the liquefied gas heaters 2 and 3 may be horizontally placed at a low position or obliquely placed at a low position.

Circuit diagram of the system of the present invention according to an embodiment Sectional view of the storage tank device of the same embodiment

Explanation of symbols

1 Bulk storage tank 2/3 Liquefied gas heater 4 Heating dedicated heat source 5/6 Heater 7 Venturi tube

Claims (5)

A storage tank device for storing the liquefied gas in a liquid state and capable of supplying the liquefied gas liquid through a siphon tube raised from the inner bottom by a head pressure or / and its own weight from the take-off valve, and the take-out from the storage device A liquefied gas liquid is supplied through a valve, and then the gas phase portion is pressurized in a sealed state, whereby the supplied liquefied gas liquid can be delivered, and the liquefied gas heater is supplied. A heat source that pressurizes the gas phase part of the liquefied gas warmer by heating the liquefied gas liquid in the warmer and generating vapor pressure, and transfer filling in which the liquefied gas liquid is sent from the liquefied gas warmer The liquefied gas warmer and two heat sources corresponding to the liquefied gas warmer are provided, and the operation of only one liquefied gas warmer side of each heat source that is fully charged is controlled. Connected with the storage device of the warmer Each liquid delivery line connected to the gas phase line and the transfer / filling destination device is alternately opened and closed, and can be switched to each liquefied gas heater via the take-off valve in conjunction with the opening and closing control. A liquid receiving line to be connected is provided, and a part of the liquefied gas liquid in a pressurized state of one liquefied gas warmer in a fully filled state is applied to the liquid receiving line, and the negative pressure generated at this time causes the aforementioned A liquefied gas transfer and filling system characterized in that a liquefied gas liquid that is at a level lower than that of the take-off valve is provided via a venturi pipe that can be sucked from the siphon pipe and supplied to the other liquefied gas warmer. By applying the liquefied gas liquid injection pressure from one liquefied gas warmer to the Venturi tube, the other liquefied gas warmer is liquefied by summing the injection amount and the suction amount from the storage tank due to negative pressure. The liquefied gas transfer and filling system according to claim 1 which supplies gas liquid. 3. A liquid level gauge for detecting a level signal of a liquefied gas liquid is provided in each liquefied gas warmer, and the liquid receiving line is switched and controlled when the liquefied gas warmer is fully filled by the level signal. Liquefied gas transfer and filling system. The liquefied gas transfer and filling system according to claim 1, 2 or 3, wherein the heat source is hot water. The liquefied gas transfer and filling system according to any one of claims 1 to 4, wherein the storage tank device is a bulk storage tank of liquefied gas liquid, and the transfer and filling destination device is a liquefied gas wheel via a dispenser.

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