JP5056355B2 - High pressure liquefied gas storage vaporization apparatus and high pressure liquefied gas storage vaporization method - Google Patents

Description

  The present invention relates to a high-pressure liquefied gas storage vaporization apparatus and a high-pressure liquefied gas storage vaporization method that operate overnight.

  Liquefied natural gas (LNG), a kind of high-pressure liquefied gas, is obtained by cooling natural gas mainly composed of methane generated from the ground to about −162 ° C. into a liquid. When natural gas is liquefied into LNG, pretreatment such as desulfurization and dehydration is performed. For this reason, when LNG is burned, the amount of emission of sulfur oxides and the like is small compared to petroleum and clean energy.

  LNG is transported by sea from LNG tankers from the country of origin and imported to a large-scale storage facility installed in Japan's port. LNG transported to a large-scale storage facility may be filled in a transport container of a lorry vehicle and transported to a satellite base. Here, since LNG must be transported while being kept at an ultra-low temperature, it is necessary to use a lorry vehicle equipped with a special transport container having a heat insulating structure.

  In a satellite base (gas utilization facility), LNG is supplied from a lorry vehicle to a gas storage tank, and supplied to gas utilization facilities such as a boiler for power generation as required by a user (for example, Patent Document 1).

  In a gas utilization facility such as a power generation apparatus using LNG as described in Patent Document 1, in order to supply LNG to the gas utilization facility, the pressure inside the gas storage tank is always kept higher than the supply destination. There is a need.

Therefore, a method is widely used in which a part of the LNG in the gas storage tank is taken out, the extracted LNG is vaporized, returned to the gas storage tank again, and the pressure inside the gas storage tank is kept constant.
JP 2002-168149 A

  In the gas utilization facility as described above, it is necessary to have a qualified person such as a security officer resident during the gas production act. For this reason, even during the nighttime when the demand for gas utilization facilities decreases, security personnel are resident as long as the gas utilization facilities are operating, and if they are not resident, the operation is stopped. Currently. In particular, the act of taking out part of the LNG in the gas storage tank, vaporizing the extracted LNG, returning it to the gas storage tank again, and maintaining the pressure inside the gas storage tank constant is a gas production action.

  However, although the amount of gas used decreases, there is a desire to continue to operate the gas utilization facility even in a predetermined time zone such as at night. For this reason, there has been a problem that it is necessary to increase the burden on security personnel and increase the operating costs such as personnel costs.

  Therefore, in view of the above-mentioned problems of the gas utilization facility, the present invention provides a high-pressure liquefied gas storage capable of safely continuing operation of the gas utilization facility without having personnel such as security personnel resident in a specific time zone. An object of the present invention is to provide a vaporizer and a high-pressure liquefied gas storage vaporization method.

  In order to solve the above-described problems, a typical configuration of a high-pressure liquefied gas storage vaporizer according to the present invention is a gas storage tank that stores high-pressure liquefied gas, and supplies the high-pressure liquefied gas from the gas storage tank to gas utilization equipment. A gas supply path, a pressure holding mechanism for vaporizing the high-pressure liquefied gas, returning it to the gas storage tank again, and maintaining a constant pressure inside the gas storage tank, and a pressure holding mechanism for taking out the high-pressure liquefied gas from the gas storage tank The extraction path opening / closing part that opens and closes the extraction path to be supplied to, the abnormality detection part that detects whether or not the gas storage tank is abnormal, and if the abnormality detection part detects an abnormality, An extraction section opening / closing section that stops returning the vaporized gas to the gas storage tank by closing the extraction path in a predetermined time zone, and the alarm section opens / closes the extraction path Part If the abnormality detection unit detects the abnormality while closing the take-off path is characterized by notifying the alert to at least a remote location.

  With the above configuration, in a predetermined time zone, the extraction path opening / closing unit can stop the gas production act of returning the vaporized gas to the gas storage tank by closing the extraction path of the high-pressure liquefied gas. Therefore, it is not necessary to make personnel such as security personnel resident in a predetermined time zone when the gas production act is not performed. On the other hand, the gas supply from the gas storage tank which is not considered as a gas production act to the gas utilization facility can always be performed without resident personnel such as security personnel. In other words, it is possible to continue to operate the gas utilization facility that is not a gas production act without resident personnel such as security personnel in a predetermined time zone in which the demand for gas decreases.

  You may further provide the pressure control part which controls a pressure holding | maintenance mechanism and makes pressure higher than the pressure at the time of taking out the pressure of a gas storage tank, ie, the pressure of a normal state.

  As a result, the gas supply from the gas storage tank to the gas utilization facility is compared with the normal pressure of the gas storage tank in the predetermined time zone when the extraction path opening / closing section closes the high-pressure liquefied gas extraction path. Long and stable.

  The pressure holding mechanism includes a first manufacturing path for supplying a gas to hold a pressure in a normal state and a second manufacturing path for supplying a gas to hold a pressure higher than the normal state, and pressure control The unit may control the pressure of the gas storage tank by switching between the first manufacturing path and the second manufacturing path.

  Thereby, the pressure of the gas storage tank can be easily increased from the pressure in the normal state to the pressure higher than the normal state by simply switching the manufacturing route from the first manufacturing route to the second manufacturing route.

  The pressure control unit may control the pressure holding mechanism so that the pressure of the gas storage tank is higher than the normal state for a predetermined time before the extraction path opening / closing unit closes the extraction path.

  Thereby, only for a predetermined time before the take-out path opening / closing section closes the take-out path, the pressure of the gas storage tank is made higher than the normal state, so that the supply from the lorry vehicle is not hindered and the pressure is efficiently increased. be able to.

  The abnormality detection unit is a pressure abnormality detection unit that detects an abnormality in the pressure inside the gas storage tank, a temperature abnormality detection unit that detects an abnormality in the temperature of the high-pressure liquefied gas supplied from the gas storage layer, and a high-pressure liquefaction inside the gas storage tank. One or more of a liquid level abnormality detection unit that detects a decrease in gas level and a leak detection unit that detects leakage of the high-pressure liquefied gas from the gas storage tank may be included.

  When the pressure abnormality detection unit is included, a pressure abnormality in the gas storage tank can be detected, for example, when the gas supply amount increases and the gas in the gas storage tank decreases or when a gas leak occurs. When the temperature abnormality detection unit is included, it is possible to detect whether or not the temperature in the gas storage tank is within the applicable range. When the liquid level abnormality detection unit is included, the gas consumption of the gas utilization equipment increases, the gas supply from the gas storage tank increases, the gas in the gas storage tank decreases, or the gas leaks It can be detected that the liquid level of the liquefied gas in the isogas storage tank is below the applicable range. When the leak detector is included, the leak of gas from the gas storage tank can be detected.

  The high pressure liquefied gas may be liquefied natural gas (LNG). Thereby, it can adapt to LNG utilization facilities, such as a power plant.

  In order to solve the above-described problems, a typical configuration of a high-pressure liquefied gas storage vaporization method according to the present invention includes a gas storage step of storing high-pressure liquefied gas in a gas storage tank, and gas utilization of the high-pressure liquefied gas from the gas storage tank. When the gas supply step to supply the equipment, the extraction path opening / closing step for opening / closing the extraction path for extracting the high-pressure liquefied gas from the gas storage tank, and the extraction path opening / closing step are opened, the extracted high-pressure liquefied gas is vaporized. The pressure storage step for returning to the gas storage tank again to keep the pressure inside the gas storage tank constant, the abnormality detection step for detecting whether or not the gas storage tank is abnormal, and the abnormality detection step An alarm notification step for notifying the facility and / or a remote location of an alarm when an abnormality is detected, and the extraction route opening / closing step is performed at a predetermined time zone. A gas production stop step that stops returning the gas vaporized to the gas storage tank by closing the path, and when an abnormality detection step occurs in the gas production stop step, the alarm notification step includes at least a remote location It is characterized by notifying an alarm.

  You may further include the pressure | voltage rise step which controls a pressure holding step and makes the pressure of a gas storage tank higher pressure than a normal state.

  The pressure increasing step may be performed for a predetermined time before stopping the return of the gas vaporized to the gas storage tank in the extraction path opening / closing step.

  In the abnormality detection step, at least an abnormality in the pressure inside the gas storage tank, an abnormality in the temperature of the high-pressure liquefied gas supplied from the gas storage layer, a decrease in the liquid level of the high-pressure liquefied gas inside the gas storage tank, from the gas storage tank One or more of the leaks of the high-pressure liquefied gas may be detected.

  The high pressure liquefied gas in the high pressure liquefied gas storage vaporization method may be liquefied natural gas (LNG).

  The constituent elements based on the technical idea of the high-pressure liquefied gas storage vaporizer and the description thereof can be applied to the high-pressure liquefied gas storage vaporization method.

  As described above, according to the high-pressure liquefied gas storage vaporization apparatus and high-pressure liquefied gas storage vaporization method of the present invention, it is possible to continue operating the gas utilization facility without resident personnel such as security personnel in a predetermined time zone. Is possible.

  An embodiment of a high-pressure liquefied gas storage vaporizer according to the present invention will be described with reference to the drawings. The dimensions, materials, and other specific numerical values shown in the following embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. Further, in the present specification and drawings, constituent elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  In the following embodiments, a high-pressure liquefied gas storage vaporization apparatus and a high-pressure liquefied gas storage vaporization method that enable a gas utilization facility to continue to be operated without personnel such as security personnel staying at a predetermined time zone will be described. To do. Here, the gas boiler (satellite base) using the high-pressure liquefied gas storage vaporizer will be described using a gas boiler as an example. However, the present invention is not limited to this, and a gas power generation facility or the like may be used. In order to facilitate understanding of the present embodiment, the overall configuration of the gas boiler will be described first, and then the features of the embodiment will be described in detail.

(Gas boiler 100)
FIG. 1 is an explanatory diagram illustrating an overall configuration of a gas boiler 100 as an example of a gas utilization facility that uses a high-pressure liquefied gas storage vaporizer. The gas boiler 100 includes high-pressure liquefied gas storage vaporizers 200 and 400 and a gas utilization facility 110, and includes a boiler 102 that is a gas utilization facility and a condenser 104.

  The high-pressure liquefied gas storage vaporizers 200 and 400 supply LNG to the boiler 102 described later.

  The boiler 102 burns the gas supplied from the high-pressure liquefied gas storage vaporizers 200 and 400 to generate high-temperature and high-pressure steam.

  The condenser 104 is generated in the boiler 102 and collects excess water vapor to be supplied to the production line, cooled, returned to water, and sent to the boiler 102 again. Cooling water is always circulated in the condenser 104, and the water vapor is rapidly cooled and liquefied.

  Hereinafter, the configuration of the high-pressure liquefied gas storage vaporizers 200 and 400 in the gas boiler 100 will be described.

(First embodiment)
In this embodiment, it is possible to continue operating the gas utilization facility without keeping personnel such as security personnel resident in a predetermined time zone, and maintaining the pressure before the predetermined time zone closing the extraction route. A high-pressure liquefied gas storage vaporizer and a high-pressure liquefied gas storage that can increase the gas supply amount in a predetermined time zone by changing the pressure of the gas storage tank from the normal state by switching the components of the mechanism A vaporization method will be described.

(High pressure liquefied gas storage vaporizer 200)
FIG. 2 is an explanatory diagram illustrating the configuration of the high-pressure liquefied gas storage vaporizer 200. The high-pressure liquefied gas storage vaporizer 200 includes a gas storage tank 202, a gas supply path 210, a take-out path opening / closing section 222, a pressure holding mechanism 230, a pressure control section 240, an abnormality detection section 250, and an alarm section 260. It is comprised including.

  The gas storage tank 202 stores LNG as high-pressure liquefied gas supplied from the tank of the lorry vehicle 204. Since LNG is an ultra-low temperature liquid of about −162 ° C., the inside of the gas storage tank 202 has a double structure (so-called thermos structure) with low thermal conductivity. In the present embodiment, the gas storage tank 202 uses an above-ground type, but is not limited to this, and it is sufficient if high-pressure liquefied gas can be stored, and an underground type can also be suitably used.

  The gas supply path 210 includes a gas supply evaporator 212, a pressure adjusting unit 214, a boil-off gas (BOG) heater 216, and a buffer tank 218, and is a gas utilization facility from the gas storage tank 202. The vaporized LNG is supplied to the boiler 102.

  The gas supply evaporator 212 heats LNG and vaporizes it to make it gas.

  The pressure adjusting unit 214 adjusts the gas that has become a gas in the gas supply evaporator 212 to an adaptive pressure of the boiler 102 that is a gas utilization facility, and supplies it to the subsequent buffer tank 218. In this embodiment, the adaptive pressure is about 0.29 MPa to 0.15 MPa.

  The boil-off gas (BOG) heater 216 heats the BOG generated by natural heat input from the outside of the gas storage tank 202 and supplies it to the subsequent buffer tank 218. Since BOG is about −2 ° C., the piping may freeze if it is not heated. For this reason, it is necessary to heat up to an adaptive temperature with the boil-off gas (BOG) heater 216.

  The buffer tank 218 absorbs fluctuations in the amount of gas used in the supplied gas and gas utilization equipment. Thereby, gas can be stably supplied to gas utilization equipment.

  The take-out route opening / closing unit 222 takes out LNG from the gas storage tank 202 and opens and closes a take-out route that is supplied to a pressure holding mechanism 230 described later. In the present embodiment, the extraction path opening / closing unit 222 uses a solenoid valve, but the present invention is not limited to this.

  The take-out route opening / closing unit 222 closes the take-out route for taking out LNG from the gas storage tank 202 in a predetermined time zone. In the present embodiment, the predetermined time zone is, for example, from 17:00 to 9:00 on the next day, but is not limited thereto, and may be a time zone in which the demand for gas decreases.

  The pressure holding mechanism 230 includes a pressurized evaporator 232, a first manufacturing path 234, and a second manufacturing path 236, and the LNG taken out from the take-out path opening / closing unit 222 is transferred by the pressurized evaporator 232. It vaporizes and returns to the gas storage tank 202 again, and the pressure of the gas storage tank 202 is kept constant.

  The pressurized evaporator 232 vaporizes and pressurizes the LNG supplied from the take-out path opening / closing unit 222.

  The first manufacturing path 234 supplies vaporized LNG from the pressurized evaporator 232 to the gas storage tank 202 in order to maintain the pressure of the gas storage tank 202 at a normal pressure. In the present embodiment, the normal pressure is about 0.4 MPa.

  The second manufacturing path 236 supplies vaporized LNG from the pressure evaporator 232 to the gas storage tank 202 in order to maintain the pressure of the gas storage tank 202 at a pressure higher than the normal state. In this embodiment, the pressure higher than the normal state is about 0.6 MPa.

  The pressure control unit 240 controls the pressure of the gas storage tank 202 to a pressure higher than the normal state (for example, 0.6 MPa) by switching from the first manufacturing path 234 to the second manufacturing path 236 of the pressure holding mechanism 230. .

  By simply switching the first manufacturing path 234 to the second manufacturing path 236, the pressure of the gas storage tank 202 can be switched from the pressure (0.4 MPa) in the normal state to the pressure (0.6 MPa) higher than the normal state. Therefore, since the pressure of the gas storage tank can be easily increased to a higher pressure (0.6 MPa) than the normal state, the gas storage tank 202 is in the predetermined time zone in which the extraction path opening / closing unit 222 closes the LNG extraction path. Compared to the normal pressure (0.4 MPa), the gas can be supplied stably for a long time.

  The pressure control unit 240 switches between the first manufacturing path 234 and the second manufacturing path 236 of the pressure holding mechanism 230, but it is not necessary to completely close the first manufacturing path 234, and the first manufacturing path 234 is opened. The second manufacturing path 236 may be opened while the gas storage tank 202 is at a pressure higher than the normal pressure from the normal pressure.

  In order to stop returning the vaporized gas to the gas storage tank 202, which is a gas production activity, by the extraction path opening / closing unit 222 closing the extraction path in a predetermined time zone, it is necessary to make personnel such as security personnel resident. Disappear. On the other hand, the gas supply from the gas storage tank 202, which is not considered as a gas production act, to the boiler 102, which is a gas utilization facility, can always be performed without resident personnel such as security personnel.

  The abnormality detection unit 250 includes a pressure abnormality detection unit 252, a temperature abnormality detection unit 254, a liquid level abnormality detection unit 256, and a leakage detection unit 258, and whether or not the gas storage tank 202 has an abnormality. Is detected.

  The pressure abnormality detection unit 252 uses, for example, a semiconductor pressure sensor. When the gas supply amount from the gas storage tank 202 increases and the gas in the gas storage tank 202 decreases from a predetermined amount, or when a gas leak occurs. A pressure abnormality in the gas storage tank 202 is detected. Furthermore, the pressure abnormality detection unit 252 detects an abnormality even when the gas supply amount from the gas storage tank 202 decreases and the supply gas pressure increases.

  The temperature abnormality detection unit 254 uses, for example, a temperature sensor using a thermocouple, and detects whether or not the temperature in the gas storage tank 202 is within the applicable range. In this embodiment, the application range is -196 ° C to 40 ° C. Further, the temperature abnormality detection unit 254 detects an abnormality even when the temperature of the gas downstream of the gas delivery evaporator 212 is lowered.

  The liquid level abnormality detection unit 256 uses, for example, a differential pressure type, and the gas consumption of the gas utilization facility increases, the gas supply amount from the gas storage tank 202 increases, and the gas in the gas storage tank 202 decreases. It is detected that the liquid level of the LNG in the gas storage tank 202 is not more than the applicable range in the case of gas leakage or gas leakage. The application range of the gas storage tank is determined by the capacity. Since the capacity of the gas storage tank 202 of this embodiment is 100 kl, the application range is 20 kl to 90 kl. In this embodiment, since the height of the gas storage tank 202 is 14.7 m and the diameter is about 2 m, the applicable range is about 4.6 m to 13.0 m. The differential pressure equation is a method of measuring the gas phase and liquid phase pressure in the gas storage tank 202 and calculating the liquid level from the pressure difference ΔP.

  The leak detection unit 258 uses, for example, a diffusion type, measures the methane concentration contained in the LNG, and detects the gas leak from the gas storage tank 202. The leak detection unit 258 can also use, for example, an optical fiber gas detection system.

  When the abnormality detection unit 250 detects an abnormality, the alarm unit 260 notifies an alarm in a facility and / or a remote place where the high-pressure liquefied gas storage vaporizer 200 is held.

  In addition, the alarm unit 260 notifies the alarm to at least a remote place in a predetermined time zone in which the extraction path opening / closing unit 222 closes the LNG extraction path from the gas storage tank 202. Thereby, even if personnel such as security personnel are in a remote place, it is possible to notify the abnormality, and it is possible to monitor the high-pressure liquefied gas storage vaporizer 200 more reliably and safely.

(High-pressure liquefied gas storage vaporization method)
Subsequently, the above-described high-pressure liquefied gas storage vaporizer 200 closes the take-out path opening / closing unit 222 in a predetermined time zone, and the high-pressure liquefied gas storage that can be continuously supplied to the gas utilization facility that is not considered to be a gas production act. The vaporization method will be described.

  FIG. 3 is a flowchart showing the flow of the high-pressure liquefied gas storage vaporization method using the high-pressure liquefied gas storage vaporization apparatus 200.

  First, LNG, which is a high-pressure liquefied gas, is stored in the gas storage tank 202 from the lorry vehicle 204 (S300: gas storage step). The extraction path opening / closing unit 222 determines whether or not it is a predetermined time period for closing the extraction path, and opens / closes the extraction path for extracting LNG from the gas storage tank 202 (S302: extraction path opening / closing step).

  When it is determined in the extraction route opening / closing step S302 that it is not the predetermined time zone, an extraction route for extracting LNG from the gas storage tank 202 is opened (S304: extraction step).

  Next, it is determined whether or not the extraction route opening / closing unit 222 is before a predetermined time period for closing the extraction route (S306: pre-stop determination step).

  In the pre-stop determination step S306, when it is determined that it is before the predetermined time period, the LNG taken out from the gas storage tank 202 is included in the pressure holding mechanism 230 by the pressure control unit 240. Switching from 234 to the second production path 236 (S308: production path switching step), the pressure of the gas storage tank 202 is increased to a pressure higher than the normal state (for example, 0.6 MPa) (S310: pressure increase step).

  In the pre-stop determination step S306, if it is determined that it is not before the predetermined time period, the LNG taken out from the gas storage tank 202 is transferred to the gas storage tank in the first manufacturing path 234 included in the pressure holding mechanism 230. In order to maintain the pressure of 202 at the normal pressure, the vaporized LNG from the pressurized evaporator 232 is supplied to the gas storage tank 202 (S312: pressure maintaining step).

  When it is determined in the extraction route opening / closing step S302 that it is the predetermined time zone, the extraction route for extracting the LNG from the gas storage tank 202 is closed (S314: extraction stop step).

  It is detected whether or not the gas storage tank 202 is abnormal in the pressure holding step S312 and the extraction stop step S314 (S316: abnormality detection step). In the abnormality detection step S316, if no abnormality is detected, that is, if it is operating normally, the supply of LNG from the gas storage tank 202 to the boiler 102, which is a gas utilization facility, continues (S318: gas supply step). .

  When an abnormality is detected in the abnormality detection step S316, the alarm unit 260 notifies an alarm in the facility that holds the high-pressure liquefied gas storage vaporizer 200 and / or in a remote place (S320: alarm notification step). In particular, in the alarm notification step S320, the alarm unit 260 notifies the alarm to at least a remote place when an abnormality is detected in the extraction stop step S312. Thereby, even if personnel such as security personnel are in a remote place, it is possible to notify the abnormality, and it is possible to monitor the high-pressure liquefied gas storage vaporizer 200 more reliably and safely.

  Furthermore, when an alarm is notified in alarm notification step S320, it is determined whether or not the abnormality detected in abnormality detection step S316 is a serious failure (S322: abnormality type determination step). When it is determined in the abnormality type determination step S322 that a serious failure has occurred, the gas supply path 210 is blocked (S324: gas supply path blocking step). In the present embodiment, a serious failure is a case where the pressure abnormality detection unit 252 detects an abnormality in which the gas supply amount from the gas storage tank 202 decreases and the supply gas pressure increases, or the temperature abnormality detection unit 254 This is a case where an abnormality relating to a decrease in the temperature of the gas downstream of the gas delivery evaporator 212 is detected.

  If it is determined in the abnormality type determination step S322 that there is no major failure, that is, if it is a minor failure, the gas supply step S318 is continued.

  As described above, in the high-pressure liquefied gas storage vaporizer 200 of the present embodiment, the gas that has been vaporized into the gas storage tank 202 by the extraction path opening / closing unit 222 stopping the extraction of the high-pressure liquefied gas in a predetermined time zone. The gas production act of returning can be stopped. Therefore, it is not necessary to make a staff member such as a security staff resident in a predetermined time zone. In other words, it is possible to continue operating the gas utilization facility without having personnel such as security personnel stay in the predetermined time zone. Further, the pressure in the gas storage tank 202 can be increased only by switching the manufacturing path constituting the pressure holding mechanism 230, and if the pressure is increased before a predetermined time period, the gas utilization in the predetermined time period is performed. It becomes possible to supply gas to the facility stably for a long time.

(Second embodiment)
In the first embodiment, the high-pressure liquefied gas storage and vaporization apparatus that can increase the gas supply amount in a predetermined time zone by switching to the production path to increase the pressure of the gas storage tank 202 higher than the normal state. The high-pressure liquefied gas storage vaporization method has been described, but by adjusting the pressure holding mechanism, it is possible to make the pressure of the gas storage tank 202 higher than that in the normal state so that it lasts for a predetermined period of time. In the second embodiment, the configuration of the high-pressure liquefied gas storage vaporization apparatus and the high-pressure liquefied gas storage vaporization method will be described.

(High pressure liquefied gas storage vaporizer 400)
FIG. 4 is an explanatory diagram for explaining the configuration of the high-pressure liquefied gas storage vaporizer 400. The high-pressure liquefied gas storage vaporizer 400 includes a gas storage tank 202, a gas supply path 210, a take-out path opening / closing section 222, a pressure holding mechanism 430, a pressure control section 440, an abnormality detection section 250, and an alarm section 260. It is comprised including. Constituent elements having substantially the same functions as those of the above-described high-pressure liquefied gas storage vaporizer 200 are assigned the same reference numerals, and descriptions thereof are omitted.

  The pressure holding mechanism 430 includes a pressurized evaporator 232 and a first manufacturing path 434. The LNG supplied by the take-out path opening / closing unit 222 is vaporized by the pressurized evaporator 232 and stored again. It returns to the tank 202 and the pressure of the gas storage tank 202 is kept constant.

  The first production path 434 includes a variable valve, and in a normal state, the LNG vaporized from the pressure evaporator 232 is stored in the gas storage tank 202 in order to keep the pressure of the gas storage tank 202 at a normal pressure. To supply.

  The pressure control unit 440 controls the first manufacturing path 434 so that the pressure of the gas storage tank 202 becomes higher than the normal state for a predetermined time before the extraction path opening / closing unit 222 closes the extraction path.

  Thereby, it is possible to efficiently increase the pressure by making the pressure of the gas storage tank 202 higher than the normal state only for a predetermined time before the extraction is stopped by the extraction path opening / closing unit 222.

(High-pressure liquefied gas storage vaporization method)
Subsequently, the above-described high-pressure liquefied gas storage vaporizer 400 closes the extraction path at the extraction path opening / closing unit 222 in a predetermined time zone, and can continuously supply gas utilization equipment that is not considered as a gas production act. A high-pressure liquefied gas storage vaporization method will be described.

  FIG. 5 is a flowchart showing a flow of a high-pressure liquefied gas storage vaporization method using the high-pressure liquefied gas storage vaporization apparatus 400.

  First, LNG, which is a high-pressure liquefied gas, is stored in the gas storage tank 202 from the lorry vehicle 204 (S500: gas storage step). The extraction path opening / closing unit 222 determines whether or not it is a predetermined time period for closing the extraction path, and opens / closes the extraction path for extracting LNG from the gas storage tank 202 (S502: extraction path opening / closing step).

  If it is determined in the extraction route opening / closing step S502 that it is not the predetermined time zone, an extraction route for extracting LNG from the gas storage tank 202 is opened (S504: extraction step).

  Next, it is determined whether or not the extraction route opening / closing unit 222 is before a predetermined time period for closing the extraction route (S506: pre-stop determination step).

  In the pre-stop determination step S506, when it is determined that it is before the predetermined time zone, the LNG taken out from the gas storage tank 202 is included in the pressure holding mechanism 230 by the pressure control unit 440. 434 is adjusted (S508: first production path adjustment step), and the pressure of the gas storage tank 202 is increased to a pressure higher than the normal state (for example, 0.6 MPa) (S510: pressure increase step).

  When it is determined in the pre-stop determination step S506 that it is not before the predetermined time period, the LNG taken out from the gas storage tank 202 is set to the normal pressure in the gas storage tank 202 in the first manufacturing path 434. In order to maintain the pressure, vaporized LNG from the pressure evaporator 232 is supplied to the gas storage tank 202 (S512: pressure maintaining step).

  If it is determined in the extraction route opening / closing step S502 that it is the predetermined time zone, the extraction route for extracting LNG from the gas storage tank 202 is closed (S514: extraction stop step).

  It is detected whether or not the gas storage tank 202 is abnormal in the pressure holding step S512 and the extraction stop step S514 (S516: abnormality detection step). When abnormality is not detected in abnormality detection step S516, that is, when it is operating normally, the supply of LNG from gas storage tank 202 to boiler 102, which is a gas utilization facility, continues (S518: gas supply step). .

  When an abnormality is detected in the abnormality detection step S516, the alarm unit 260 notifies an alarm in the facility that holds the high-pressure liquefied gas storage vaporizer 200 and / or in a remote place (S520: alarm notification step). In particular, in the alarm notification step S520, the alarm unit 260 notifies the alarm to at least a remote place when an abnormality is detected in the extraction stop step S512.

  Furthermore, when an alarm is notified in alarm notification step S520, it is determined whether or not the abnormality detected in abnormality detection step S516 is a serious failure (S522: abnormality type determination step). When it is determined in the abnormality type determination step S522 that there is a serious failure, the gas supply path 210 is blocked (S524: gas supply path blocking step). In the present embodiment, a serious failure is a case where the pressure abnormality detection unit 252 detects an abnormality in which the gas supply amount from the gas storage tank 202 decreases and the supply gas pressure increases, or the temperature abnormality detection unit 254 This is a case where an abnormality relating to a decrease in the temperature of the gas downstream of the gas delivery evaporator 212 is detected.

  If it is determined in the abnormality type determination step S522 that there is no major failure, that is, if it is a minor failure, the gas supply step S518 is continued.

  As described above, in the high-pressure liquefied gas storage and vaporization apparatus 400 of the present embodiment, as in the first embodiment, in the predetermined time zone in which the demand for gas decreases, it is possible to operate the gas without resident personnel such as security personnel. It is possible to keep the gas utilization facility that is not a manufacturing activity in operation. Furthermore, the pressure of the gas storage tank can be increased by adjusting the manufacturing path that constitutes the pressure holding mechanism 230 before the predetermined time period, and the gas supply in the predetermined time period can be stably extended for a long time. Can be done.

(Other embodiments)
In the first embodiment and the second embodiment described above, the pressure in the gas storage tank 202 is normally set by the pressure control unit before a predetermined time period when the extraction path opening / closing unit 222 closes the extraction path (stops the extraction). The pressure was higher than the state.

  However, the present invention is not limited to this, and it is sufficient that the gas storage tank 202 has a pressure suitable for the gas utilization facility in a predetermined time period in which the extraction path is closed by the extraction path opening / closing unit 222. The extraction by the extraction path opening / closing unit 222 may be stopped while the pressure of the tank 202 is kept in a normal state.

  Although the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, in the above embodiment, LNG is used as the high-pressure liquefied gas. However, the present invention is not limited to this, and any high-pressure liquefied gas may be used, and argon, nitrogen, or the like can be suitably used.

  In addition, each process in the high pressure liquefied gas storage vaporization method of this specification does not necessarily need to process in time series along the order described as a flowchart, and is a process (for example, parallel processing) performed in parallel or individually. Alternatively, processing by an object) may be included.

  The present invention can be used for a high-pressure liquefied gas storage vaporization apparatus and a high-pressure liquefied gas storage vaporization method.

It is explanatory drawing explaining the whole structure of the gas boiler as an example of the gas utilization plant | facility using a high pressure liquefied gas storage vaporizer. It is explanatory drawing explaining the structure of the high pressure liquefied gas storage vaporization apparatus concerning 1st embodiment. It is the flowchart which showed the flow of the high pressure liquefied gas storage vaporization method using the high pressure liquefied gas storage vaporization apparatus concerning 1st embodiment. It is explanatory drawing explaining the structure of the high pressure liquefied gas storage vaporization apparatus concerning 2nd embodiment. It is the flowchart which showed the flow of the high pressure liquefied gas storage vaporization method using the high pressure liquefied gas storage vaporization apparatus concerning 1st embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Gas boiler, 102 ... Boiler, 104 ... Condenser, 200, 400 ... High-pressure liquefied gas storage vaporizer, 202 ... Gas storage tank, 204 ... Raleigh vehicle, 210 ... Gas supply path, 212 ... Gas feed evaporator, 214 ... pressure adjusting part, 216 ... boil-off gas (BOG) heater, 218 ... buffer tank, 222 ... take-out path opening / closing part, 230, 430 ... pressure holding mechanism, 232 ... pressure evaporator, 234, 434 ... first production Path, 236 ... second manufacturing path, 240, 440 ... pressure control section, 250 ... abnormality detection section, 252 ... pressure abnormality detection section, 254 ... temperature abnormality detection section, 256 ... liquid level abnormality detection section, 258 ... leakage detection section , 260 ... Alarm section

Claims (11)

A gas storage tank for storing high-pressure liquefied gas;
A gas supply path for supplying the high-pressure liquefied gas from the gas storage tank to a gas utilization facility;
A pressure holding mechanism for vaporizing the high-pressure liquefied gas, returning it to the gas storage tank again, and maintaining a constant pressure inside the gas storage tank;
An extraction path opening / closing portion that opens and closes an extraction path that takes out the high-pressure liquefied gas from the gas storage tank and supplies it to the pressure holding mechanism;
An anomaly detector that detects whether the gas storage tank has an anomaly;
When the abnormality detection unit detects an abnormality, an alarm unit for notifying the facility and / or a remote place,
With
The extraction path opening / closing unit stops returning the gas vaporized to the gas storage tank by closing the extraction path at a predetermined time zone, and the alarm unit has the extraction path opening / closing unit closing the extraction path. A high-pressure liquefied gas storage vaporizer characterized by alerting at least a remote location when the abnormality detection unit detects an abnormality in the meantime.   The high-pressure liquefied gas storage vaporizer according to claim 1, further comprising a pressure control unit that controls the pressure holding mechanism to make the pressure of the gas storage tank higher than a normal state. The pressure holding mechanism is
A first manufacturing path for supplying gas to maintain the normal pressure;
A second manufacturing path for supplying gas in order to maintain a pressure higher than the normal state;
With
The high-pressure liquefied gas storage vaporizer according to claim 2, wherein the pressure control unit controls the pressure of the gas storage tank by switching between the first manufacturing path and the second manufacturing path.   The said pressure control part controls the said pressure holding mechanism so that the pressure of the said gas storage tank may become a pressure higher than a normal state for the predetermined time before the said extraction path | route opening / closing part closes an extraction path | route. Item 4. The high-pressure liquefied gas storage vaporizer according to Item 2 or Item 3. The abnormality detection unit
A pressure abnormality detection unit that detects an abnormality in pressure inside the gas storage tank, a temperature abnormality detection unit that detects an abnormality in temperature of the high-pressure liquefied gas supplied from the gas storage layer, and the high-pressure liquefied gas inside the gas storage tank The liquid level abnormality detection part which detects the liquid level fall of this, and the leak detection part which detects the leak of the said high voltage | pressure liquefied gas from the said gas storage tank are included, One or more is included. High pressure liquefied gas storage vaporizer.   6. The high-pressure liquefied gas storage vaporizer according to claim 1, wherein the high-pressure liquefied gas is liquefied natural gas (LNG). A gas storage step for storing the high-pressure liquefied gas in the gas storage tank;
A gas supply step of supplying the high-pressure liquefied gas from the gas storage tank to a gas utilization facility;
An extraction path opening and closing step for opening and closing an extraction path for extracting the high-pressure liquefied gas from the gas storage tank;
When the extraction path opening / closing step is open, the extracted high-pressure liquefied gas is vaporized, returned to the gas storage tank again, and a pressure holding step for keeping the pressure inside the gas storage tank constant;
An abnormality detection step for detecting whether or not the gas storage tank has an abnormality, and
When an abnormality is detected in the abnormality detection step, an alarm notification step for notifying an alarm in a facility and / or a remote place;
Including
The extraction path opening / closing step further includes a gas production stop step of stopping returning the vaporized gas to the gas storage tank by closing the extraction path at a predetermined time zone,
When the abnormality detection step occurs in the gas production stop step, the alarm notification step notifies the alarm to at least a remote place.   The high-pressure liquefied gas storage vaporization method according to claim 7, further comprising a step of controlling the pressure holding step so as to make the pressure of the gas storage tank higher than a normal state.   9. The high-pressure liquefied gas storage vaporization method according to claim 8, wherein the pressurization step is performed for a predetermined time before stopping the return of the gas vaporized to the gas storage tank in the extraction path opening / closing step.   In the abnormality detection step, at least an abnormality in the pressure inside the gas storage tank, an abnormality in the temperature of the high-pressure liquefied gas supplied from the gas storage layer, a decrease in the liquid level of the high-pressure liquefied gas inside the gas storage tank, 8. The high-pressure liquefied gas storage vaporization method according to claim 7, wherein one or a plurality of leakages of the high-pressure liquefied gas from the gas storage tank are detected.   The high-pressure liquefied gas storage vaporization method according to any one of claims 7 to 10, wherein the high-pressure liquefied gas is liquefied natural gas (LNG).

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