JP2014151274A - Vapor recovery apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vapor recovery apparatus to improve environmental performance and vapor recovery performance further.SOLUTION: In a vapor recovery apparatus 1,: it is determined as needed whether or not it is necessary to perform adsorption treatment succeeding to the completion of depressurization treatment during the execution of desorption or depressurization treatment; and the depressurization treatment in depressurization suppressing the generation of noise or depressurization in which priority is given to the quick completion of the depressurization treatment to the suppression of the generation of noise is selectively performed according to a determination result.

Description

  In the present invention, when the volatile liquid is filled in the liquid storage tank, the vapor of the volatile liquid (vapor) from the gas (gas) released from the liquid storage tank when the volatile liquid is filled. The present invention relates to a vapor recovery device that separates and recovers slag.

  In a fuel supply facility such as a gas station where fuel such as gasoline is replenished to a replenishment target such as a vehicle, fuel composed of a volatile liquid is stored in a liquid storage tank installed in the site. Since the fuel in the liquid storage tank decreases every time fuel supply work is performed on the replenishment target, if the amount of fuel liquid in the liquid storage tank decreases in the fuel supply facility, fuel delivery by the tank truck is appropriately performed from the oil tank station. In response, he receives unloading of fuel from a tank truck.

  The storage tank has a high-pressure gas phase in the tank (in the upper part of the tank) so that the internal pressure of the tank does not become abnormally high due to temperature rise in the tank or unloading of fuel from the tank truck. A vent pipe is provided for releasing a part of the atmosphere of the (space portion) to the outside. Normally, the vent pipe communicates and opens on one side to the gas phase inside the tank, while the other side extends to the site height (for example, 4 meters above the ground) and is opened and opened to the outside as an air vent through an atmospheric valve. It has a structure. The atmospheric valve opens / closes according to the pressure difference (the magnitude of the differential pressure) between the atmospheric pressure and the internal pressure of the vent pipe, that is, the pressure of the atmosphere in the gas phase in the tank where one side of the vent pipe communicates. Supply and exhaust the gas phase inside. Therefore, when the atmosphere of the gas phase portion in the tank rises in pressure and the pressure difference with the outside air exceeds a certain value, the air valve opens based on the pressure difference between the two. As a result, an abnormally high-pressure atmosphere in the gas phase portion in the tank is partly released to the outside through the vent hole of the vent pipe, and the internal pressure of the tank is reduced, resulting in an abnormal pressure in the tank. The rise can be suppressed.

  By the way, when unloading fuel from a tank truck, as the level of fuel in the storage tank rises as unloading of the supplementary fuel proceeds to one storage tank, the volume of the gas phase portion in the upper part of the tank increases. As the pressure in the tank increases, the air valve of the vent pipe opens, and a part of the gas containing fuel vapor in the gas phase part enters the atmosphere from the vent hole of the vent pipe. It may be released as it is. This release of gas containing fuel vapor not only causes environmental pollution, but for fuel supply facilities that have a large amount of fuel to be unloaded from tank trucks to storage tanks, this released gas The amount of fuel vapor contained is also a liquid amount that cannot be ignored, leading to unnecessary loss of fuel that has undergone unloading.

  Therefore, in a fuel supply facility such as a gas station, a vapor recovery device as described in Patent Document 1, for example, is provided, and the fuel that has been discharged from the vent pipe in the past when the fuel is unloaded from the tank truck. The fuel vapor component is separated from the gas containing the vapor, and the fuel vapor component is removed, and then released. The separated fuel vapor component is returned to the liquid storage tank and collected. Therefore, in the vapor recovery apparatus described in Patent Document 1, for example, using an adsorbent such as silica gel, an adsorption process for adsorbing a fuel vapor component from a gas containing fuel vapor released from a liquid storage tank is performed, By releasing the gas after removing the fuel vapor component, the gas containing the fuel vapor is prevented from being released into the atmosphere as it is. In addition, the fuel vapor component adsorbed by the adsorbent at that time is subjected to a desorption process for desorbing the fuel component from the adsorbent, and the desorbed fuel vapor component is returned to the liquid storage tank to be recovered. It is configured to suppress unnecessary loss. This desorption treatment requires an atmosphere in the tank of the adsorption tower filled with the adsorbent that adsorbs the fuel vapor component in a state where the introduction of the gas containing the fuel vapor released from the liquid storage tank is refused. In response to this, it is performed by sucking to a negative pressure state (extremely low pressure state) while using purge gas in combination, and desorbing the fuel vapor component adsorbed on the adsorbent from the adsorbent.

Patent No. 5060159 (Japanese Patent Laid-Open No. 2008-264733)

  By the way, in the vapor recovery device that performs the adsorption process and the desorption process as described above, and separates and recovers the fuel vapor component from the gas containing the fuel vapor released from the liquid storage tank, the desorption process is completed or completed. At that time, the atmosphere in the tank of the adsorption tower filled with the adsorbent is in a negative pressure state (extremely low pressure state).

  Therefore, in the vapor recovery apparatus, when the desorption process is completed, a depressurizing gas such as clean air or inert gas that does not contain fuel vapor is introduced into the adsorption tower tank, In order to continue the depressurization process to return the atmosphere to atmospheric pressure or its vicinity, and newly perform the adsorption process, the pressure state in the tank is returned to the original pressure state (reference pressure state). ing. This depressurization process is provided, for example, in communication with the inside of the tank of the adsorption tower, and during the desorption process, the open / close valve is opened to open the depressurization gas. It introduce | transduces into the tank of an adsorption tower from the outside through.

  This depressurization process can be implemented and terminated as soon as the desorption process is completed so that the process can proceed to the adsorption process. It is desired to be able to respond quickly to the separation and recovery of fuel vapor components.

  However, in the depressurization process, the pressure of the depressurization gas introduced from the outside into the tank of the adsorption tower through the on-off valve is simply increased to increase the magnitude of the gas introduction rate (the amount of gas introduced per unit time). If an attempt is made to shorten the time (time required for the depressurization process), the generation of the supply sound of the depressurization gas increases, resulting in noise during the depressurization process of the vapor recovery device. In addition, in the depressurization process, if the magnitude of the supply speed of the depressurization gas supplied from the outside into the adsorption tower tank is suppressed so as not to generate noise, the depressurization process is terminated immediately and adsorption is performed. Even in the case of fuel unloading and replenishment work that cannot be transferred to a new process, the fuel vapor component cannot be quickly separated or recovered.

  For example, in the vapor recovery device, when the unloading of fuel from the tank truck to the storage tank is newly started during the depressurization process in the tank of the adsorption tower, the gas phase portion in the tank Gas containing fuel vapor whose pressure has increased cannot be introduced into the tank of the adsorption tower because the vapor recovery device has not shifted to the adsorption process, and the fuel vapor component is removed by separation and recovery of the fuel vapor component. Can not be released after. In addition, if the transition to the adsorption process of the vapor recovery device is significantly delayed with respect to the start of unloading of the fuel, the fuel vapor component is removed and the gas cannot be released after that. The pressure in the gas phase part in the inside becomes abnormally high and the air valve in the vent pipe opens, and the gas containing fuel vapor in the gas phase part in the tank remains in the atmosphere through the vent hole in the vent pipe It can also be released.

  The present invention has been made in view of the above-described problems, and suppresses the generation of noise during the depressurization process, and also separates the fuel vapor component contained in the gas discharged from the liquid storage tank. To provide a vapor recovery device that can improve the environmental performance and the vapor recovery performance further by promptly terminating the depressurization process and proceeding to the adsorption process when quick recovery is required. With the goal.

  In order to achieve the above-described problem, the vapor recovery apparatus according to the present invention determines whether or not it is necessary to perform an adsorption process during the desorption process or the depressurization process. Performs decompression processing that suppresses the generation of noise, and if necessary, performs the decompression processing that prioritizes the quick completion of the decompression processing to suppress the generation of noise, and performs the decompression processing. It is characterized by automatically achieving harmony between noise suppression and rapid depressurization.

  More specifically, the present invention relates to a vapor of a volatile liquid contained in a discharge gas that is contained in an adsorbent that adsorbs a vapor of a volatile liquid and is discharged from a liquid storage tank in which the volatile liquid is stored. Is adsorbed by the adsorbent to remove the vapor of the volatile liquid from the released gas, and the vapor of the volatile liquid adsorbed by the adsorbent is returned to the storage tank. The desorption means for desorbing the vapor of the volatile liquid adsorbed on the adsorbent by sucking the inside of the adsorbing means containing the adsorbent to a negative pressure state with the introduction of the released gas released, and the desorption Decompression means for introducing a depressurizing gas from the outside into the adsorption means and depressurizing the inside of the adsorption means in a negative pressure state by suction by the desorption means at the end of the suction inside the adsorption means by the means A vapor recovery device equipped with Volatilization contained in the discharge gas released from the liquid storage tank by the adsorption means during the suction inside the adsorption means by the desorption means or during the introduction of the depressurization gas into the inside of the adsorption means by the depressurization means A transition determining means for determining whether or not it is necessary to adsorb the vapor of the volatile liquid, and a depressurizing means at a normal time when it is determined by the transition determining means that it is not necessary to adsorb the vapor of the volatile liquid It is necessary to limit the amount of depressurized gas introduced per unit time per unit time so as to suppress the generation of supply air noise, complete the depressurization inside the adsorption means, and adsorb volatile liquid vapor by the transition judgment means In special times when it is determined that there is a problem, the amount of depressurization gas introduced by the depressurization means per unit time is not limited so as to suppress the generation of the supply air sound, and the inside of the adsorption means is shorter than normal. Prolapse Characterized in that it comprises a de-pressure control means to complete the.

  According to the present invention, in the vapor recovery apparatus, during the desorption process or the depressurization process, has it become necessary to adsorb the vapor of the volatile liquid contained in the discharge gas released from the liquid storage tank? Whether or not, and according to the determination result, the depressurization process that suppresses the generation of noise, or the depressurization process that prioritizes the quick completion of the depressurization process with respect to the suppression of the generation of noise, Since it can be automatically selected and performed, it is possible to achieve harmony between noise suppression and speed of depressurization during depressurization processing.

  Further, according to the present invention, even when the unloading of the volatile liquid from the tank lorry vehicle to the liquid storage tank is started during the desorption process or the depressurization process, the desorption process is quickly performed. Since the pressure treatment can be terminated and the adsorption treatment can be performed, the environmental performance and the vapor recovery performance can be further improved.

  Further, problems, configurations, and effects of the present invention other than those described above will be clarified by the following description of embodiments.

It is explanatory drawing about one Example of the gas station where the system configuration | structure of the vapor collection apparatus which concerns on one embodiment of this invention, and the vapor collection apparatus which concerns on this Embodiment were applied. It is a flowchart of the desorption process performed by the vapor collection apparatus which concerns on this Embodiment, and a depressurization process.

  A configuration of a vapor recovery apparatus according to an embodiment of the present invention will be described with reference to the drawings, taking as an example a case where it is applied to a fuel supply facility as a fuel supply facility for supplying fuel such as gasoline to a supply object such as a vehicle. .

  FIG. 1 is an explanatory diagram of a system configuration of a vapor recovery apparatus according to an embodiment of the present invention and an example of a gas filling station to which the vapor recovery apparatus according to the present embodiment is applied.

  First, the configuration of an example of a filling station 10 to which the vapor recovery apparatus 1 according to the present embodiment is applied will be described with reference to FIG.

  In the gas station 10, a plurality (three in the illustrated example) of oil storage tanks (liquid storage tanks) 11-n (11-1, 11-2, 11-3) are buried in the basement of the site. It is configured. Each of the oil storage tanks 11-n stores the same or the same type of oil (for example, fuel liquid types such as high-octane gasoline and regular gasoline).

  Also, refueling machines 12-n (12-1, 12-2, 12-3) for replenishing fuel to replenishment targets such as vehicles are installed corresponding to the refueling areas formed on the site surface. . Each of the oil storage tanks 11-n and each of the refueling machines 12-n that supply the fuel of the oil type stored in each of the oil storage tanks 11-n includes the refueling machine 12-n from the basement surface above the oil storage tank 11-n. It is connected in communication via a liquid supply pipe 13-n extending in the ground toward the lower side of the site where n is installed.

  In addition, in the illustrated gas station 10, one oil machine 12-n is installed for each oil tank 11-n, but a plurality of oil machines 12-n are installed for one oil tank 11-n. However, the configuration of the filling station 10 is not limited to the illustrated configuration, such as sharing the individual oil storage tanks 11-n with the plurality of fueling machines 12-n.

  Each liquid supply pipe 13-n has a tank side end communicating with a liquid phase portion L in the tank of the oil storage tank 11-n, and an oil supply side end communicating with the pump inflow side of the oil dispenser 12-n. The oil stored in the oil storage tank 11-n can be pumped up by a pump (not shown) of the oil feeder 12-n.

  Each of the oil feeders 12-n pumps the oil stored in the oil storage tank 11-n connected in communication via the liquid supply pipe 13-n by a pump, and operates a fuel supply nozzle (not shown) provided at the tip of the oil supply hose. By doing so, the oil liquid is supplied to the replenishment target such as a vehicle. During this refueling operation (fuel supply operation), each refueling machine 12-n measures and outputs a refueling amount (fuel supply amount) for a replenishment target with a flow meter (not shown). Accordingly, the amount of liquid in each of the oil storage tanks 11-n decreases by the amount of oil supplied each time a refueling operation is performed on the replenishment target using the refueling machines 12-n that are connected to each other. It will be.

  Therefore, oil filling ports 14-n for replenishing the oil liquid stored in the respective oil storage tanks 11-n are provided in the appropriate locations on the site that do not interfere with the oil supply work in the gas filling station 10 to the respective oil storage tanks 11-n. It is arranged correspondingly. Each oil supply port 14-n communicates with the inside of the corresponding oil storage tank 11-n through an oil supply pipe 15-n extending underground on the site surface. Each of the oil filling ports 14-n receives unloading of the replenishing oil from the tank truck that has loaded and transferred the replenishing oil from the tank to the hatch (compartment chamber). The oil inlet side connecting end is detachable, and can be closed by a detachable lid (not shown) except during unloading work.

  When unloading the replenishing fluid from the hatch of the tank truck, the lubrication port 14-n is connected to the unloading port of the tank truck connected to the corresponding hatch loaded with the replenishing fluid by an unloading hose. Is done. Then, by opening the hatch bottom valve provided at the liquid discharge port on the bottom surface of the corresponding hatch in the tank truck and the unloading valve provided at the unloading port, the replenishment oil liquid loaded on the corresponding hatch is operated. Is unloaded to the oil storage tank 11-n. Accordingly, the amount of liquid in each oil storage tank 11-n is equal to the amount of unloading every time it receives unloading of the replenishing oil liquid loaded and transferred to the hatch of the tank truck from the oil supply port 14-n connected in communication. It will increase by (replenishment oil amount).

  As described above, the amount of liquid in each oil storage tank 11-n increases or decreases by performing the unloading operation of the replenishing oil solution or the refueling operation to the replenishment target, and the boundary between the liquid phase portion L and the gas phase portion G inside the tank. The liquid level height position of the oil liquid stored in the tank is also displaced according to the amount of stored liquid.

  Therefore, each oil storage tank 11-n is provided with a liquid level sensor (liquid level sensor) 16-n in order to measure the level or amount of the oil stored in the tank. The measurement output of each liquid level sensor 16-n is transmitted to a liquid amount management device 17 disposed in a gas station office or the like, and the liquid amount management device 17 records the amount of liquid stored in each oil storage tank 11-n every moment. And displayed and managed.

  In addition, in each oil storage tank 11-n, the pressure in the atmosphere of the gas phase portion G in the tank does not become abnormally high or low due to the temperature change in the tank or the supply / unloading of oil. A vent pipe 18-n is provided. Each vent pipe 18-n opens on one side to the gas phase portion G in the tank, while the other side extends to a site height (for example, 4 meters above the ground). Opened as a ventilation hole. Each atmospheric valve 19-n is a breather valve, and the internal pressure of each ventilation pipe 18-n, that is, the pressure of the atmosphere of the gas phase portion G in the tank of the oil storage tank 11-n is a difference of a predetermined value or more with respect to the atmospheric pressure. When the pressure is generated, the valve is opened, and the pressure of the atmosphere of the gas phase portion G in the tank is adjusted. Specifically, the atmospheric valve 19-n is opened when the pressure in the atmosphere of the gas phase portion G in the tank becomes higher than a predetermined value with respect to the atmospheric pressure due to the temperature rise in the tank or unloading of the replenishing oil liquid. A part of the gas phase G in the tank is discharged to the outside so that the atmosphere does not become abnormally high. The atmospheric valve 19-n is also used when the pressure in the atmosphere of the gas phase portion G in the tank becomes lower than the predetermined value by a predetermined value or less with respect to the atmospheric pressure due to the temperature drop in the tank or the repeated supply of the oil liquid due to the refueling operation. Is opened and air is supplied from the outside so that the pressure in the atmosphere of the gas phase portion G in the tank does not become abnormally low. It should be noted that the magnitude of the differential pressure with respect to the atmospheric pressure when the atmospheric valve 19-n is opened (positive pressure and negative with respect to the atmospheric pressure). The predetermined value as an absolute value not considering the pressure) may be different depending on whether the pressure of the atmosphere of the gas phase portion G in the tank is high or low.

  Next, the system configuration of the vapor recovery apparatus 1 according to the present embodiment applied to the gas station 10 having the above-described configuration will be described with reference to FIG.

  As shown in FIG. 1, the vapor recovery apparatus 1 according to the present embodiment includes a vapor recovery unit 20, an adsorption unit 30, a gas supply / exhaust unit 40, a desorption / reflux unit 50, and a control unit 60.

  The vapor recovery unit 20 introduces the atmosphere of the gas phase portion G including the fuel vapor (fuel vapor) of the oil storage tank 11-n into the adsorption unit 30. The vapor recovery unit 20 has a vapor recovery pipe 21 whose one side communicates with the gas phase portion G inside the tank of the oil storage tank 11-n and whose other side communicates with the adsorption tower 31 of the adsorption unit 30. In the illustrated example, since the vapor recovery apparatus 1 is shared by a plurality of oil storage tanks 11-n, the vapor recovery pipe 21 has a branch pipe on one side communicating with the gas phase portion G of the oil storage tank 11-n. On the other hand, the other side communicating with the adsorption tower 31 of the adsorption part 30 is a common pipe part 23 communicated with each branch pipe part 22-n.

  The tip of each branch pipe part 22-n constituting one side end of the vapor recovery pipe 21 is connected to the vent pipe 18-n of each oil storage tank 11-n, and the air in each tank of the oil storage tank 11-n. It communicates with the phase part G. In addition, the tip of the common pipe part 23 that constitutes the other end of the vapor recovery pipe 21 communicates with the adsorption tower 31 of the adsorption part 30.

  In addition, a tank valve 24-n is provided in each branch pipe portion 22-n of the vapor recovery pipe 21. The tank valve 24-n is connected between the gas phase portion G in the tank of the oil storage tank 11-n that communicates with each branch pipe portion 22-n and the common pipe portion 23 that communicates with the adsorption tower 31 of the adsorption portion 30. The oil storage tanks 11-n are individually communicated / blocked. Each tank valve 24-n is configured by, for example, an electromagnetically operated or pneumatically operated on / off valve, and opens and closes in response to the supply / stop of an operation signal. Each tank valve 24-n opens and closes to individually select and control the introduction / blocking of the atmosphere of the gas phase portion G including the fuel vapor to the common pipe section 23 for each oil storage tank 11-n.

  Further, each branch pipe portion 22-n closer to the vent pipe 18-n than the tank valve 24-n has an internal pressure of the vent pipe 18-n communicating with each branch pipe section 22-n, that is, in the tank of the oil storage tank 11-n. A pressure sensor 25-n for measuring the pressure in the atmosphere of the gas phase portion G is provided. Each pressure sensor 25-n is constituted by, for example, a differential pressure transmitter (differential pressure type pressure gauge), and the internal pressure of the vent pipe 18-n, that is, the pressure of the atmosphere of the gas phase portion G in the tank of the oil storage tank 11-n ( Pressure change) is measured by the differential pressure from atmospheric pressure. Therefore, according to the measurement output of the pressure sensor 25-n, for example, the liquid surface height of the oil liquid stored in the tank is displaced by unloading of the oil liquid, and the atmosphere of the gas phase portion G in the tank is displaced. When the pressure increases to the atmospheric pressure, it appears as a change in the differential pressure output.

  Further, an adsorption tower introduction valve 26 is disposed in the common pipe portion 23 of the vapor recovery pipe 21. The adsorption tower introduction valve 26 communicates / blocks between the common pipe section 23, in other words, all the branch pipe sections 22-n and the introduction / reflux port 33 in the adsorption tower 31 of the adsorption section 30 according to the opening / closing thereof. . The adsorption tower introduction valve 26 is configured by, for example, an electromagnetically operated or pneumatically operated on / off valve, and opens and closes in response to supply / stop of an operation signal. The adsorption tower introduction valve 26 controls the introduction / blocking of the atmosphere of the gas phase portion G containing the fuel vapor as the released gas to the adsorption tower 31 of the adsorption unit 30 according to the opening and closing thereof.

  The adsorbing unit 30 adsorbs, separates and recovers the fuel vapor component from the atmosphere of the gas phase portion G including the fuel vapor introduced through the vapor recovery unit 20. In the illustrated example, the adsorbing unit 30 stores the oil liquid of the same or the same type (for example, high-octane gasoline and regular gasoline) in each oil storage tank 11-n. n is connected to each other. Therefore, the adsorption | suction part 30 is shared with respect to each oil storage tank 11-n, and becomes the structure by which the installation space and equipment cost of the adsorption | suction part 30 were reduced. In addition, when the oil storage tanks 11-n store different types of oil (for example, high-octane gasoline (regular gasoline) and light oil), the adsorbing unit 30 is different in order to prevent contamination of different types of oil. A plurality of vapor collection pipes 21 of the vapor collection unit 20 are provided for each of the adsorption units 30.

  The adsorption unit 30 has an adsorption tower 31 filled with an adsorbent 32 for adsorbing a fuel vapor component in the tank. As the adsorbent 32, various adsorbents such as silica gel, zeolite, activated carbon capable of desorbing adsorbed gas (for example, mesophase activated carbon) can be used.

  In the adsorption tower 31, the atmosphere of the gas phase portion G containing the fuel vapor supplied via the vapor recovery unit 20 is introduced into the tank, or is adsorbed by the adsorbent 32 in the tank and separated and recovered. An introduction / reflux port 33 is formed for desorbing the fuel vapor component and returning it to the oil storage tank 11-n. In addition, the adsorption tower 31 is configured to exhaust the gas from which the fuel vapor component has been removed to the outside of the adsorption tower 31 and to remove the fuel vapor component adsorbed by the adsorbent 32 so as to be in a negative pressure state. When depressurizing and returning the pressure in the tank, for example, an exhaust / air supply port 34 for introducing a depressurizing gas is also formed.

  In addition, in the illustrated example, the adsorption tower 31 is provided with an adsorption state detection sensor 35 for monitoring the adsorption state of the fuel vapor component by the adsorbent 32 filled in the tank. The adsorption state detection sensor 35 includes, for example, a plurality of temperatures provided for each region formed by dividing the inside of the tank from the introduction / reflux port 33 side below the tank to the exhaust / air supply port 34 side above the tank. It consists of sensors. The adsorption state detection sensor 35 detects the adsorption state of the adsorbent 32 in each region by the detection output of each temperature sensor that changes in accordance with the adsorption state, so that the inside of the tank filled with the adsorbent 32 of the adsorption tower 31. The overall fuel vapor component adsorption status can be ascertained. In this case, a thermocouple, a resistance temperature detector, a thermistor, or the like is used as the temperature sensor.

  The introduction / reflux port 33 is connected to the other end of the vapor recovery pipe 21, which is the end of the vapor recovery pipe 21 constituting the vapor recovery section 20, and is connected to the other end of the vapor recovery pipe 21. 50 is also connected to one side of the fuel vapor recirculation pipe 51 composing 50. And the pressure sensor 36 for measuring the pressure of the atmosphere in the tank of the adsorption tower 31 is provided in the introduction / reflux port 33 or a pipe line in the vicinity thereof. The pressure sensor 36 is configured by, for example, a pressure transmitter (absolute pressure gauge). On the other hand, one side of the air supply / exhaust pipe 41 constituting the gas supply / exhaust section 40 is connected to the exhaust / air supply port 34 in communication.

  The gas supply / exhaust unit 40 discharges, from the adsorption tower 31, the gas, which has been removed by adsorbing the adsorbent 32 with the fuel vapor component adsorbed by the adsorbing unit 30. Moreover, when the fuel vapor component is desorbed from the adsorbent 32 filled in the tank of the adsorption tower 31, the pressure of the atmosphere in the tank of the adsorption tower 31 that is in a negative pressure state (extremely low pressure state) is set to the atmospheric pressure state. Alternatively, for example, external air is introduced into the tank of the adsorption tower 31 in order to depressurize to a reference state composed of the vicinity thereof.

  The gas supply / exhaust unit 40 has an air supply / exhaust pipe 41 having one side connected to an exhaust / air supply port 34 formed in the adsorption tower 31 of the adsorption unit 30. The other side of the air supply / exhaust pipe 41 extends to a site height (for example, 4 meters above the ground), and is opened to the atmosphere as an air supply / exhaust hole via an air valve 42. The atmospheric valve 42 is for preventing rain and dust from entering the air supply / exhaust pipe 41 from the outside, and a cover for preventing rain and dust from entering is provided in place of the atmospheric valve 42. It may be. An air supply / exhaust valve 43 is provided in the middle of the air supply / exhaust pipe 41 so as to be positioned closer to one side than the atmospheric valve 42 (closer to the adsorption unit 30 side). The supply / exhaust valve 43 is constituted by, for example, an open / close valve having a flow rate adjusting function by an electromagnetic operation type, a pneumatic operation type, a motor drive, etc., and opens / closes according to supply / stop of an operation signal. In addition to performing communication / blocking, the flow rate per unit time can be adjusted by adjusting the valve opening amount in accordance with the operation signal. In the example shown in the drawing, the release of the gas from which the fuel vapor component has been removed from the adsorption tower 31 of the adsorption unit 30 into the atmosphere and the introduction of the external atmosphere into the tank of the adsorption tower 31 are performed by one on-off valve. However, as shown in the figure, a bypass pipe section 46 is provided in the middle of the air supply / exhaust pipe 41, and an exhaust valve 44 and an air supply comprising separate dedicated on-off valves, respectively. It is good also as a structure provided with the valve | bulb 45. FIG.

  The air valve 42 functions as a breather valve in a communication state of the air supply / exhaust pipe 41 in which the air supply / exhaust valve 43 is open, and opens when the internal pressure of the air supply / exhaust pipe 41 exceeds a predetermined value with respect to the atmospheric pressure. The internal pressure of the supply / exhaust pipe 41, that is, the pressure in the tank filled with the adsorbent 32 of the adsorption tower 31 is adjusted. The magnitude of the predetermined value of the differential pressure with respect to the atmospheric pressure when the atmospheric valve 42 is opened (the predetermined value as an absolute value not considering the positive pressure and the negative pressure with respect to the atmospheric pressure) is the internal pressure of the supply / exhaust pipe 41. The value may be different between when exhausting when the pressure is higher than the atmospheric pressure and when supplying air when the pressure is low.

  Further, in relation to the atmospheric valve 19-n provided in each vent pipe 18-n described above, the difference when the internal pressure of the air supply / exhaust pipe 41 becomes higher than the atmospheric pressure and the atmospheric valve 42 opens. The magnitude of the predetermined value of the pressure is the difference when the atmospheric valve 19-n provided in each of the vent pipes 18-n opens when the internal pressure of the vent pipe 18-n becomes higher than the atmospheric pressure. The pressure is set smaller than the predetermined value. Therefore, in the illustrated example, when the internal pressure of the vent pipe 18-n, that is, the pressure of the atmosphere of the gas phase portion G in the tank of the oil storage tank 11-n with which the vent pipe 18-n communicates increases, the vapor recovery is performed. If the corresponding tank valve 24-n and the adsorption tower introduction valve 26 of the unit 20 are in the open normal state, the atmospheric valve 42 is opened prior to the atmospheric valve 19-n. As a result, the atmosphere in which the pressure in the gas phase portion G of the vent pipe 18-n and the oil storage tank 11-n has increased is not usually due to the vent pipe 18-n, but the vapor recovery pipe 21, the adsorption section of the vapor recovery section 20. The pressure is released from the vapor recovery apparatus 1 through 30 adsorption towers 31 and the supply / exhaust pipe 41 of the gas supply / exhaust section 40.

  Therefore, when the fuel is unloaded from the tank truck through the oil filler 14-n and the oil pipe 15-n corresponding to the desired oil storage tank 11-n, the atmosphere of the gas phase portion G in the tank is As the liquid level rises, that is, the pressure increases as the amount of liquid in the tank increases, if the atmosphere of the gas phase portion G is also introduced into the adsorption tower 31 of the adsorption unit 30 via the vapor recovery unit 20, In the atmosphere of the gas phase portion G containing the fuel vapor whose pressure has increased, the fuel vapor component is adsorbed by the adsorbent 32 filled in the tank of the adsorption tower 31, and passes through the supply / exhaust pipe 41 of the gas supply / exhaust section 40. Only the gas from which the fuel vapor component has been removed from the air supply / exhaust hole is released into the atmosphere, and the pressure in the tank is released. As a result, even when unloading the fuel from the tank truck to the oil storage tank 11-n, the fuel vapor whose pressure in the oil storage tank 11-n has increased without significant delay that would cause the tank to become abnormally high in pressure. If the atmosphere of the gas phase portion G that is included can be introduced into the adsorption unit 30, the gas supply / exhaust unit is formed by removing the fuel vapor component from the gas without removing the atmospheric valve 19-n of the vent pipe 18-n. The gas containing fuel vapor can be prevented from being released into the atmosphere as it is from the vent hole of the vent pipe 18-n.

  The desorption reflux unit 50 desorbs the fuel vapor component adsorbed by the adsorbent 32 filled in the tank of the adsorption tower 31 of the adsorption unit 30 and refluxes it to the oil storage tank 11-n. The desorption recirculation part 50 has a fuel vapor recirculation pipe 51 whose one side communicates with the introduction / reflux port 33 of the adsorption tower 31 in the adsorption part 30 and whose other side communicates with the gas phase part G in the tank of the oil storage tank 11-n. . In the illustrated example, the fuel vapor recirculation pipe 51 has a configuration in which the other side is directly connected to one oil storage tank 11-1 among the plurality of oil storage tanks 11-n. In this case, for example, the vent pipe 18-n may be used as long as the other connection point is a part that always communicates with the oil storage tank 11-1 without using a valve or the like. Further, in order to recirculate the desorbed fuel vapor, if the oil storage tank 11-n communicating with the other side is also an oil storage tank 11-n in which the same or the same kind of oil liquid is stored, the atmosphere of the gas phase portion G is changed. It may be different from the introduced oil storage tank 11-n. Moreover, it is not limited to one oil storage tank 11-n, but may be configured to always communicate with each of the plurality of oil storage tanks 11-n.

  In the illustrated example, the desorption / reflux unit 50 is provided with a recirculation valve 52, a vacuum pump (suction pump) 53, and a cooling unit 54 disposed in this fuel vapor recirculation pipe 51 in order from one side to the other side. It is configured.

  The recirculation valve 52 communicates / blocks the fuel vapor recirculation pipe 51 between the introduction / reflux port 33 of the adsorption tower 31 in the adsorption unit 30 and the vacuum pump 53 and the cooling unit 54 in the subsequent stage according to the opening / closing thereof. The recirculation valve 52 is configured by, for example, an electromagnetically operated or pneumatically operated on / off valve, and opens / closes in response to the supply / stop of the operation signal to communicate / block the fuel vapor recirculation pipe 51 on the suction side of the vacuum pump 53. . The recirculation valve 52 opens and closes the oil storage tank 11 in which the introduction / reflux port 33 of the adsorption tower 31 in the adsorption unit 30 is connected to the other side of the desorption / recirculation unit 50 via the vacuum pump 53 and the cooling unit 54. -Communication / blocking to the n side.

  In the illustrated example, the reflux valve 52 is configured separately from the adsorption tower introduction valve 26 of the vapor recovery unit 20, but is integrated with the adsorption tower introduction valve 26 of the vapor recovery unit 20 to perform adsorption / desorption. It is also possible to use a switching valve. In this case, the adsorption / desorption switching valve is constituted by, for example, an electromagnetically actuated or pneumatically actuated three-way valve, and the introduction / reflux port 33 of the adsorption tower 31 in the adsorption unit 30 is changed to the vapor recovery unit 20 in accordance with the operation signal. Can be selectively switched to the common pipe section 23 of the vapor recovery pipe 21 or the fuel vapor reflux pipe 51 of the reflux section 50.

  As a suction pump, the vacuum pump 53 is driven to drive the adsorbent of the adsorption tower 31 in a state where the reflux valve 52 is opened and the suction side of the vacuum pump 53 communicates with the introduction / reflux port 33 of the adsorption tower 31. The atmosphere in the tank filled with 32 is sucked. Therefore, in a state where the fuel vapor component is adsorbed on the adsorbent 32, the vacuum pump 53 is driven to desorb the fuel vapor component from the adsorbent 32, and the suction is performed together with the fuel vapor component from which the atmosphere in the tank is desorbed. Will be. The suction in the tank of the adsorption tower 31 by the vacuum pump 53 for desorbing the fuel vapor component from the adsorbent 32 is a shut-off state of the supply / exhaust pipe 41 in which the supply / discharge valve 43 of the gas supply / discharge section 40 is closed. Done in Along with this, the atmosphere in the tank is depressurized to a negative pressure state (extremely low pressure state).

  The cooling unit 54 cools and liquefies the atmosphere sucked by the vacuum pump 53 and containing the desorbed fuel vapor component desorbed from the adsorbent 32. As the cooling configuration of the cooling unit 54, for example, a configuration in which a refrigerant is compressed by a compressor and cooled, a configuration using cooling with cooling water, or the like can be used. The atmosphere containing the desorbed fuel vapor component liquefied by the cooling unit 54 and the desorbed fuel vapor component that has not been liquefied is returned to the oil storage tank 11-n from the other side of the fuel vapor recirculation pipe 51.

  The controller 60 uses the tank valve 24-n and the adsorption tower introduction valve 26 based on the outputs of various sensors such as the pressure sensors 25-n and 36 and the adsorption status detection sensor 35 described above and the output of the liquid amount management device 17. The operation of each part such as the supply / exhaust valve 43, the reflux valve 52, the vacuum pump 53, the cooling unit 54, etc. is controlled, and the execution control of the adsorption process, the desorption process, and the depressurization process of the vapor recovery apparatus 1 is performed. The control unit 60 is configured by a microcomputer including a storage unit such as a memory, for example.

  For example, in the execution control of the adsorption process, the controller 60 controls the detection output of the pressure sensor 25-n, the liquid amount output of the liquid amount management device 17 based on the detection output of the liquid level sensor 16, or the lubrication port 14-n. Based on the detection of the connection of the unloading hose to the oil storage tank 11-n, when it is detected that the unloading operation of the oil liquid from the tank truck is started, the tank of the adsorption tower 31 is filled. When the desorption of the fuel vapor component adsorbed by the adsorbent 32 and the subsequent depressurization in the tank are not performed, the adsorption process is started immediately.

  In the adsorption process, the control unit 60 performs the unloading and replenishment work while the adsorption tower introduction valve 26 is open, the reflux valve 52 is closed, and the supply / discharge valve 43 is open. By opening the tank valve 24-n related to the oil storage tank 11-n and introducing the atmosphere of the gas phase portion G including the fuel vapor, in which the pressure of the oil storage tank 11-n is increased, to the adsorption unit 30, The fuel vapor component is adsorbed by the adsorbent 32 filled in the tank to make the gas from which the fuel vapor component has been removed, and then released from the air supply / exhaust hole of the air supply / exhaust pipe 41.

  As a result, even when the pressure inside the oil storage tank 11-n rises as the fuel is unloaded from the tank truck to the oil storage tank 11-n, the adsorbent 32 filled in the tank of the adsorption tower 31. When the desorption of the tank and the subsequent depressurization in the tank have already been completed, the control unit 60 immediately opens the tank valve 24-n related to the oil storage tank 11-n and removes the oil from the oil storage tank 11-n. Since the adsorption process of the fuel vapor component contained in the released gas (atmosphere of the gas phase portion G) can be started, the gas containing the fuel vapor is directly released into the atmosphere from the vent hole of the vent pipe 18-n. Can be suppressed.

  At that time, the control unit 60 controls the tank valve 24-n ′ related to the oil storage tank 11-n ′, which is not subjected to the unloading replenishment operation, to close the oil storage tank 11− by the unloading replenishment operation. It is possible to control so that the atmosphere released from the gas phase portion G of n does not flow into the vent pipe 18-n ′ or the tank of the oil storage tank 11-n ′ where unloading and replenishment work is not performed.

  On the other hand, even if the control unit 60 detects that the oil liquid unloading work from the tank truck is started, the fuel vapor adsorbed by the adsorbent 32 filled in the tank of the adsorption tower 31 is detected. When the component desorption process or the subsequent depressurization process in the tank is performed, the desorption process and the depressurization process are quickly completed, and then the above-described adsorption process is executed.

  In contrast to the execution control of the adsorption process, in the vapor recovery apparatus 1 according to the present embodiment, the control unit 60 performs the desorption process and the execution process as shown in FIG. Execution control of the decompression process is performed.

  FIG. 2 is a flowchart of the desorption / decompression process executed by the vapor recovery apparatus according to the present embodiment.

  In the vapor recovery apparatus 1 according to the present embodiment, the desorption / decompression process shown in FIG. 2 is performed when the control unit 60 has completed unloading of fuel from the tank truck to the oil storage tank 11-n, for example. Performed when detected. The detection of completion of unloading may be detected based on the removal of the unloading hose connected to the lubrication port 14-n and the output of the liquid amount management device 17, or from a tank truck. You may make it detect when predetermined time (for example, 30 minutes) has passed since the unloading of the fuel with respect to the oil storage tank 11-n was started. Furthermore, an unloading completion button is provided near the filling port 14-n or an appropriate place such as a gas station, and by detecting that the operator has operated the unloading completion button when the unloading work is completed. The completion of unloading may be detected. As described above, the method of detecting completion of unloading and replenishment has various detection methods depending on the unloading and replenishment work, and is not limited to the above-described configuration.

  When the control unit 60 detects the completion of unloading of fuel to the oil storage tank 11-n as described above, the control unit 60 controls each part of the apparatus to execute the following desorption process and depressurization process.

  First, in order to start the desorption process, the controller 60 activates the vacuum pump 53 provided in the fuel vapor recirculation pipe 51 of the desorption recirculation section 50 in step S010 (hereinafter, description of the steps is omitted). If the cooling unit 54 is not in the cooling configuration at any time, the cooling unit 54 is also activated.

  In S020, in order to measure the desorption time tc in the tank of the adsorption tower 31, the control unit 60 resets and starts the desorption timer Tc provided as an internal timer, and starts measuring the desorption time tc.

  In S030, the control unit 60 is in an open state in order to introduce the gas containing fuel vapor during the previous execution of the adsorption process or during the execution of the adsorption process, and the adsorption tower of the vapor recovery unit 20 While the introduction valve 26 is closed, the reflux valve 52 of the desorption reflux unit 50 which is in the closed state in the adsorption process is opened, and the communication in the tank of the adsorption tower 31 is desorbed and refluxed from the vapor recovery unit 20 side. The communication is switched to the part 50 side. Thereby, the inside of the tank of the adsorption tower 31 is in a state of being communicated with the suction side of the vacuum pump 53.

  In S040, the control unit 60 is in a valve open state to release the gas from which the fuel vapor component has been removed during the previous execution of the adsorption process or during the execution of the adsorption process. The supply / discharge valve 43 is closed. Thereby, the inside of the tank of the adsorption tower 31 is shut off from the outside.

  When the desorption process is started by the processes shown in S010 to S040, the atmosphere in the tank filled with the adsorbent 32 of the adsorption tower 31 is sucked into the negative pressure state (very low pressure state) by the vacuum pump 53, Desorption of the fuel vapor component adsorbed by the adsorbent 32 is performed. At that time, the atmosphere in the tank of the adsorption tower 31 containing the sucked desorbed fuel vapor component is supplied to the cooling unit 54, and the desorbed fuel vapor component is liquefied. The atmosphere including the desorbed fuel vapor component liquefied by the cooling unit 54 and the desorbed fuel vapor component that has not been liquefied is returned to the oil storage tank 11-n from the other side of the fuel vapor recirculation pipe 51.

  While performing the desorption process in this manner, the control unit 60 determines in S050 whether or not the unloading work of the oil liquid from the tank truck is started on the oil storage tank 11-n, and in S060, It is repeatedly monitored whether a predetermined detachment time T0 that has been set in advance has elapsed.

  At that time, the control unit 60 determines whether or not the unloading operation of the oil liquid has started, for example, a predetermined change in the pressure detected by the pressure sensor 25-n provided in the vapor recovery unit 20 or a liquid amount management. Detection is based on a predetermined increase in the amount of liquid in the oil storage tank 11-n measured by the device 17, or the like. The specified desorption time T0 is filled in the tank of the adsorption tower 31 set in advance according to the size in the tank of the adsorption tower 31, the filling amount of the adsorbent 32, the suction capacity of the vacuum pump 53, and the like. This corresponds to the drive time of the vacuum pump 53 required to desorb the fuel vapor component from the adsorbent 32. In the example shown in the figure, the specified detachment time T0 is set and registered in the control unit 60 as control data in advance.

  If the start of unloading work from the tank truck is not detected (S050, NO), and the control unit 60 detects the passage of the specified detachment time T0 (S060, YES), the control unit 60 performs vacuum in S080. The drive of the pump 53 is stopped and the desorption process is normally terminated. In this case, the necessity of early transition to the adsorption process by accelerating the end of the subsequent depressurization process in the tank of the adsorption tower 31 corresponds to the normal time that has not yet been determined at the end of the desorption process. Then, at the normal time when the desorption process of the specified desorption time T0 is completed, the control unit 60 then calculates the introduction amount (air supply amount) per unit time of the depressurization gas below S090. The depressurization process limited to suppress the occurrence is started.

  On the other hand, if the start of the unloading work from the tank truck is detected (S050, YES), the control unit 60 detects S070 before the specified detachment time T0 has elapsed (S060, NO). Thus, the driving of the vacuum pump 53 is quickly stopped, and the desorption process is terminated halfway. In the illustrated example, the desorption process is terminated in S070 regardless of the length of the actual desorption time within the specified desorption time T0. However, although it is shorter than the predetermined desorption time T0, the minimum necessary amount is shown. It is confirmed whether or not the desorption has been performed by the time tc of the desorption timer Tc, waits for the completion of this minimum desorption, stops the driving of the vacuum pump 53, and terminates the desorption process halfway. It is also possible to do. In these cases, it is necessary to make an early transition to the adsorption process, which corresponds to a special time that has already been determined during or at the end of the desorption process. Then, in a special time when the desorption process of the specified desorption time T0 is terminated halfway, the control unit 60 thereafter suppresses the generation of the supply air sound by introducing the depressurization gas per unit time at S135 or lower. Without being limited to the above, a special-time depressurization process that is completed in a shorter time than the normal time is started.

  Here, in the situation where the control unit 60 has completed the desorption process regardless of whether the desorption process at the specified desorption time T0 has been completed or completed, the adsorption tower introduction valve 26 of the vapor recovery unit 20 is still closed. On the other hand, the recirculation valve 52 of the desorption recirculation part 50 is in an open state, and the oil storage tank 11-n is in an open state regardless of whether the tank valve 24-n of the vapor recovery part 20 is open or closed. The atmosphere of the gas phase portion G containing fuel vapor is not introduced into the adsorption tower 31 of the adsorption unit 30.

  In view of this, the control unit 60 performs the normal depressurization process in which the introduction amount per unit time of the depressurization gas is limited so as to suppress the generation of the supply air sound as described below. .

  First, the control unit 60 supplies the introduction amount per unit time of the depressurization gas introduced into the tank filled with the adsorbent 32 of the adsorption tower 31 in S090 in order to start the normal depressurization process. In order to limit the generation of aerial noise, in the illustrated example, the valve opening degree of the supply / exhaust valve 43 provided in the supply / exhaust pipe 41 of the gas supply / exhaust section 40 is limited to a half-open state and opened.

  In S100, the control unit 60 uses the first depressurization provided as an internal timer to measure the first depressurization time T1 in which the introduction amount of the depressurization gas into the tank of the adsorption tower 31 is limited. The timer Ta1 is reset and started, and the time of the depressurization execution time ta1 for counting the first depressurization time T1 is started. The first depressurization time T1 is set and registered in advance in the control unit 60 as control data, similarly to the specified desorption time T0.

  When the first depressurization process in the normal state in which the introduction amount per unit time of the depressurization gas is limited by the processes shown in S090 to S100 so as to suppress the generation of the supply air noise is started, The atmosphere that does not contain fuel vapor is introduced from the outside as a depressurizing gas into the tank 31 through the supply / exhaust pipe 41 of the gas supply / exhaust section 40. At that time, the atmospheric valve 42 of the gas supply / exhaust unit 40 is operated in a negative pressure state (extremely low pressure state) at the end of the desorption process in the tank of the adsorption tower 31 by opening the supply / exhaust valve 43 in a half-open state. Thus, the valve is opened by the pressure difference between the atmospheric pressure and the internal pressure of the supply / exhaust pipe 41, that is, the pressure in the desorbed adsorption tower 31. At that time, the amount of air (decompression gas) introduced into the tank of the adsorption tower 31 through the supply / exhaust pipe 41 is the half-open state controlled in S090 at the beginning of the normal depressurization process. The supply / exhaust valve 43 limits the amount of introduction per unit time that suppresses the generation of supply air noise, so that no noise is generated during decompression.

  In this way, when the first depressurization process at the beginning of the normal depressurization process is performed with the introduction amount per unit time that suppresses the generation of the supply air sound, the time of the first depressurization timer Ta1 is counted. With the passage of the depressurization execution time ta1 based on the above, the pressure in the tank of the adsorption tower 31 gradually increases from the negative pressure state (extremely low pressure state).

  Therefore, during the first depressurization process in this way, the control unit 60 determines whether or not a predetermined first depressurization time T1 has elapsed in S110, and in S120, Similarly to S050, it is repeatedly monitored at any time whether or not the unloading operation of the oil liquid from the tank truck has been started on the oil storage tank 11-n.

  Here, with the progress of the first depressurization process, the pressure in the tank of the adsorption tower 31 that was initially in a negative pressure state (extremely low pressure state) increases with time, and a pressure difference from the atmospheric pressure. Decrease. As a result, the introduction amount per unit time of the depressurizing gas restricted by the supply / discharge valve 43 in the half-open state is substantially reduced compared to the initial amount by the amount that the pressure difference between the two decreases with time. . In the illustrated example, the first depressurization time T1 is in a differential pressure state that does not exceed the introduction amount per unit time for suppressing the generation of the supply air sound even when the opening degree of the supply / discharge valve 43 is fully opened. Even if the valve opening of the supply / exhaust valve 43 is fully opened, the first pressure release state does not exceed the introduction amount per unit time that suppresses the generation of the supply air sound. This corresponds to the time required for the pressure in the tank of the adsorption tower 31 to increase with the pressure treatment.

  The controller 60 does not detect the start of unloading work from the tank lorry vehicle (S120, NO), and detects the elapse of the prescribed first depressurization time T1 (S110, YES), It is not yet determined at the end of the first depressurization process at the normal time that it is necessary to make an early transition to the adsorption process. Assuming that the normal time continues, the first depressurization process at the beginning of the normal time is started. From the above depressurization process, the normal second depressurization process of S130 and below is executed.

  On the other hand, the controller 60 detects the start of the unloading work from the tank truck before detecting the passage of the prescribed first depressurization time T1 (S110, NO) (S120, YES), it is necessary to make an early transition to the adsorption process, which corresponds to a special time that has already been determined during the normal depressurization process. Then, in this case, the control unit 60 terminates the first depressurization process at the beginning of the normal depressurization process halfway, and when it is necessary to perform early transition to the adsorption process, Perform pressure treatment. In the example shown in the drawing, the control unit 60 performs the first depressurization time T1 and the first depressurization time at the normal time based on the timing of the first depressurization timer Ta1 at the time of detecting the start of the unloading work in S120. Depending on the relationship with the depressurization execution time ta1 due to the process, either the depressurization process at the special time shown in S135 or less or the same depressurization process as the second depressurization process in the normal time shown in S130 or less In this case as well, the process starts as a special-time decompression process regardless of the passage of the first decompression time T1. Further, in any case of the depressurization process at S135 or less or S130 or less, the first depressurization time T1 has not elapsed, so the amount of introduction of the depressurization gas per unit time is calculated as the supply sound. Priority is given to completing the depressurization in the tank of the adsorption tower 31 in a shorter time than the normal time without actively restricting the introduction amount per unit time so as to suppress the generation.

  Here, the control unit 60 does not detect the start of the unloading work from the tank truck (S120, NO), and detects the passage of the prescribed first depressurization time T1 (S110, YES). When the first depressurization process at the beginning of the normal depressurization process is completed, the normal second depressurization process is performed as follows.

  In this case, due to the completion of the first depressurization process (S110, YES), the pressure in the tank of the adsorption tower 31 suppresses the generation of an air supply sound even when the valve opening degree of the supply / discharge valve 43 is fully opened. Since the differential pressure with respect to the atmospheric pressure does not exceed the introduction amount of the depressurizing gas per unit time, the control unit 60 fully opens the valve opening degree of the supply / discharge valve 43 in S130.

  In S140, the control unit 60 resets the second depressurization timer Ta2 provided as an internal timer in order to measure the second depressurization time T2 by the second depressurization process at the normal time. Start, and start timing of the depressurization execution time ta2 for measuring the second depressurization time T2.

  When the second depressurization process at the normal time is started by the processes shown in S130 to S140, the depressurization gas enters the tank of the adsorption tower 31 through the supply / exhaust pipe 41 of the gas supply / exhaust section 40. As mentioned above, the atmosphere containing no fuel vapor is supplied. In this case, the processing shown in S130 to S140 corresponds to the normal second depressurization processing after the first depressurization processing at the beginning of the normal depressurization processing is completed. In the normal second depressurization process, even if the valve opening of the supply / discharge valve 43 is fully opened, the introduction amount of the depressurization gas per unit time is the first at the beginning of the normal depressurization process. The amount of introduction per unit time that has substantially decreased when the depressurization processing of the first is completed is made closer to the amount of introduction per unit time that suppresses the generation of the supply air sound at the beginning of the first depressurization processing. Therefore, no noise is generated during decompression.

  Then, while the control unit 60 performs the normal second depressurization process in this manner, in S150, it is determined whether or not a predetermined second depressurization time T2 has elapsed. The monitoring is repeated from time to time. This second depressurization time T2 is set in advance, after the start of the normal second depressurization process, the original reference in which the pressure in the tank of the adsorption tower 31 is in the atmospheric pressure state or in the vicinity thereof The depressurization time is sufficient to return to the pressure state.

  Then, the control unit 60 detects the elapse of the second depressurization time T2 (S150, YES), and when the second depressurization process at the normal time is completed, the depressurization process is terminated, In order to prepare for the subsequent adsorption process, in S160, the reflux valve 52 of the desorption reflux unit 50 opened in the desorption process S030 is closed, and in S170, the vapor valve closed in the desorption process S030. The adsorption tower introduction valve 26 of the recovery unit 20 is opened, and the communication in the tank of the adsorption tower 31 is switched from the desorption reflux unit 50 side to the vapor recovery unit 20 side. The normal depressurization process consisting of the depressurization process 2 is completed. As a result, the inside of the tank of the adsorption tower 31 is in communication with each of the branch pipe parts 22-n via the common pipe part 23 of the vapor recovery pipe 21.

  As a result, during the desorption process or during the first depressurization process (normal depressurization process), the fuel vapor component contained in the atmosphere of the gas phase portion G discharged from the oil storage tank 11-n. During normal times when the first depressurization process and the second depressurization process can be completed without the need for the adsorption process, the generation of the supply sound of the depressurization gas is suppressed. By performing the depressurization process, the generation of noise during the depressurization process can be suppressed. Furthermore, even in that case, in the present embodiment, depending on the depressurization situation in the tank of the adsorption tower 31, the depressurization process is in the middle of the first depressurization process and the second depressurization process, Since the introduction amount per unit time for suppressing the generation of the supply pressure sound of the depressurization gas can be increased and changed, it is possible to achieve harmony between noise suppression in the depressurization process and rapidness of the depressurization time.

  On the other hand, if the start of unloading work from the tank truck is detected (S050, YES) before the specified desorption time T0 has elapsed (S060, NO), and the desorption process is terminated halfway (S050, YES) S070), or before detecting the passage of the prescribed first depressurization time T1 during the normal first depressurization process (S110, NO), start of unloading work from the tank truck Is detected (S120, YES), and when the first depressurization process at the beginning of the normal depressurization process is terminated halfway and the depressurization execution time ta1 of the first depressurization process is short, As a special time when it is determined that it is necessary to perform an adsorption process before the end of the depressurization process, the amount of introduction of the depressurization gas per unit time below S135 is limited to suppress the generation of the supply air sound. Without normal operation ("first decompression time T1" + "second decompression time T2 ") Start the depressurization process to complete in a short time not exceeding.

  In this case, the controller 60 fully opens the valve opening degree of the supply / discharge valve 43 in S135. In S145, the control unit 60 resets the first depressurization timer Ta3 provided as an internal timer in order to measure the third depressurization time T3 by the third depressurization process at the special time. The time for starting the depressurization execution time ta3 for measuring the third depressurization time T3 is started. When the control unit 60 detects the elapse of the third depressurization time T3 (S155, YES), the control unit 60 closes the recirculation valve 52 of the desorption recirculation unit 50 opened in S030 of the desorption process ( (S160), the adsorption tower introduction valve 26 of the vapor recovery section 20 that has been closed in S030 of the desorption process is opened (S170), and the depressurization process at the special time is completed. As a result, when it is determined that it is necessary to perform the adsorption process before the end of the depressurization process, the introduction amount of the depressurization gas per unit time is limited to suppress the generation of the supply air sound. Without a normal time, a time shorter than the completion of each of the series of the first depressurization process and the second depressurization process (“third depressurization time T3” <“first depressurization time T1”) + "Second depressurization time T2"), the depressurization process can be completed. Therefore, the delay time in which the transition to the adsorption process of the vapor recovery apparatus 1 is delayed with respect to the start of unloading of fuel can be suppressed as much as possible. As a result, the pressure in the gas phase portion G in the tank where the fuel unloading has been started becomes abnormally high, and a part of the gas containing the fuel vapor in the gas phase portion G in the tank is It is possible to surely prevent the 19-n vent holes from being released into the atmosphere as they are. In other words, by giving priority to the quick completion of the depressurization process over the suppression of noise generation, the depressurization process is completed and the adsorbing process is immediately completed at the special time when the adsorbing process is performed at the end of the depressurization process. Since the process can be shifted to the process, the environmental performance and the vapor recovery performance can be further improved.

  Similarly, before detecting the elapse of the prescribed first depressurization time T1 during the normal first depressurization process (S110, NO), the start of unloading work from the tank truck is started. Is detected (S120, YES), and when the first depressurization process at the beginning of the normal depressurization process is terminated halfway and the processing time of the first depressurization process is long, the depressurization process As a special time when it is determined that it is necessary to perform the adsorption process before the end of the process, the depressurization process at the same special time as the second depressurization process at the normal time shown in S <b> 130 and below is performed. Performance and vapor recovery performance can be further improved. It goes without saying that the “second depressurization time T2” in this case may be shorter than the “third depressurization time T3”.

  As described above, according to the vapor recovery apparatus 1 according to the present embodiment, the vapor of the volatile liquid adsorbed by the adsorption unit 30 is being desorbed by the desorption / reflux unit 50 or adsorbed by the desorption / reflux unit 50. During the depressurization by the gas supply / exhaust unit 40 of the unit 30, the adsorption unit 30 newly adsorbs the vapor of the volatile liquid from the released gas composed of the atmosphere of the gas phase portion G released from the oil storage tank 11-n. It is determined at any time whether or not the necessity has arisen, and according to the determination result, the above-described depressurization by the gas supply / exhaust unit 40 is controlled against the depressurization process by suppressing the generation of noise or the generation of noise. Since it is possible to automatically select and perform the depressurization process in which priority is given to the rapid completion of the depressurization process, it is possible to achieve harmony between noise suppression in the depressurization process and rapidness of the depressurization time.

  And the embodiment of such a vapor collection | recovery apparatus 1 is not limited to the specific embodiment demonstrated above.

  For example, in the vapor recovery apparatus 1 according to the above-described embodiment, when the desorption / decompression process shown in FIG. 2 detects that the unloading of fuel from the tank truck to the oil storage tank 11-n is completed. However, it is automatic regardless of the completion of unloading of the fuel to the oil storage tank 11-n on a regular basis or according to the detection output of the adsorption state detection sensor 35 of the adsorption tower 31. Can be applied regardless of the trigger of the process start.

  Further, in the desorption / depressurization process shown in FIG. 2, the liquid storage tank is used by the adsorption unit 30 that is performed during the desorption of the adsorption unit 30 by the desorption reflux unit 50 or during the depressurization of the adsorption unit 30 by the gas supply / discharge unit 40. As shown in S050 and S120, the determination of whether or not it is necessary to adsorb the vapor of the volatile liquid contained in the gas released from the 11-n is short. The construction is based on whether or not the unloading work of the oil liquid from the tank truck has started, which is remarkable in time. Regarding S050 and S120, the pressure state of the atmosphere containing the vapor of the volatile liquid in the gas phase portion G in the liquid storage tank 11-n is quickly volatile liquid by the adsorbing unit 30 during desorption or depressurization. For detecting the start of unloading work where the pressure rise in the tank is noticeable in a short time if it is detected that the state requiring the adsorption of vapor is in the middle of desorption or depressurization. It is not limited. For example, when the pressure of the gas phase portion G is increased due to the temperature change in the tank from before, during the desorption or depressurization, the pressure of the gas phase portion G is increased by the volatile liquid vapor promptly by the adsorption unit 30. It may be a case where it is detected that a set value that requires adsorption is exceeded.

  As for the end of the depressurization process, in the desorption / decompression process shown in FIG. 2, the depressurization execution time ta1 by the first depressurization process timed by the first depressurization timer Ta1 in S110 is a predetermined value. By detecting that the first depressurization time T1 has been reached, it is possible to indirectly detect that the pressure in the tank of the adsorption tower 31 has increased to a pressure at which the generation of the supply air sound can be suppressed. Yes. Regarding the end of the first depressurization process at the normal time, a pressure sensor for detecting the pressure in the tank of the adsorption tower 31 is provided in the adsorption unit 30, and the pressure value detected by the pressure sensor is set in advance. It is also possible to detect directly by detecting that the pressure has risen to a pressure that can suppress the generation of noise.

  In S150, by detecting that the depressurization execution time ta2 due to the second depressurization process timed by the second depressurization timer Ta2 is equal to or longer than the predetermined second depressurization time T2, the adsorption tower It is possible to indirectly detect that the pressure in the tank 31 has returned to the atmospheric pressure state or the vicinity thereof. Similarly, regarding the end of the second depressurization process at the normal time, the pressure value detected by the pressure sensor for detecting the pressure in the tank of the adsorption tower 31 is also the pressure in the atmospheric pressure state or the vicinity thereof. It is also possible to detect directly by directly detecting.

  In addition, regarding the completion of the special-time depressurization process shown in S155, the pressure value detected by the pressure sensor that similarly detects the pressure in the tank of the adsorption tower 31 becomes the pressure in the atmospheric pressure state or the vicinity thereof. It is also possible to detect directly by detecting this directly.

  As described above, the embodiment of the vapor recovery apparatus according to the present invention has a specific configuration within a range that does not depart from the gist of achieving harmony between noise suppression and speed of depressurization during depressurization processing. Various modifications can be applied, and the present invention is not limited to the embodiment described above.

1 Vapor recovery device, 10 Gas station, 11 Oil storage tank (storage tank),
L liquid phase part, G gas phase part, 12 oil supply machine, 13 liquid supply pipe, 14 oil filling port,
15 oil supply pipe, 16 liquid level sensor, 17 liquid volume control device, 18 vent pipe,
19 atmospheric valve, 20 vapor recovery section, 21 vapor recovery pipe, 22 branch pipe section,
23 common pipe, 24 tank valve, 25 pressure sensor,
26 adsorption tower introduction valve, 30 adsorption section, 31 adsorption tower, 32 adsorbent,
33 Inlet / return port, 34 Exhaust / air supply port, 35 Adsorption status detection sensor,
36 pressure sensor, 40 gas supply / exhaust section, 41 supply / exhaust pipe, 42 atmospheric valve,
43 Supply / discharge valve, 44 Exhaust valve, 45 Supply valve,
46 Bypass line part, 50 Desorption recirculation part, 51 Fuel vapor recirculation pipe,
52 reflux valve, 53 vacuum pump, 54 cooling unit,
60 control unit,

Claims (5)

By adsorbing an adsorbent that adsorbs the vapor of the volatile liquid and adsorbing the adsorbent with the vapor of the volatile liquid contained in the gas released from the liquid storage tank in which the volatile liquid is stored. Adsorption means for removing volatile liquid vapor from the released gas;
In order to recirculate the vapor of the volatile liquid adsorbed by the adsorbent to the liquid storage tank, the adsorbing means in which the adsorbent is accommodated in a state where the introduction of the released gas from the liquid storage tank is refused Desorption means for sucking the inside to a negative pressure state and desorbing the vapor of the volatile liquid adsorbed on the adsorbent;
At the end of suction inside the adsorption means by the desorption means, a depressurizing gas is introduced from the outside into the adsorption means, and the inside of the adsorption means that is in a negative pressure state by suction by the desorption means is released. A vapor recovery device comprising a depressurization means for performing pressure,
During the suction inside the adsorption means by the desorption means or the introduction of the depressurization gas into the adsorption means by the depressurization means, the release gas released from the liquid storage tank by the adsorption means Transition judging means for judging whether or not it is necessary to perform adsorption of vapor of contained volatile liquid; and
In a normal time when it is determined that the volatile liquid vapor does not need to be adsorbed by the transition determining means, the amount of the depressurizing gas introduced by the depressurizing means per unit time is suppressed from being generated. In the special case where it is determined that it is necessary to complete the depressurization of the inside of the adsorbing means and the transition judging means needs to adsorb the vapor of the volatile liquid, the depressurizing means A depressurization control means for completing the depressurization inside the adsorption means in a shorter time than the normal time without limiting the amount of gas introduced per unit time so as to suppress the generation of the supply air sound; Vapor collection device characterized by this. The transition determination means includes
By detecting that the replenishment operation of the volatile liquid to the liquid storage tank is started, the adsorption of the vapor of the volatile liquid contained in the released gas discharged from the liquid storage tank by the adsorption means is performed. 2. The vapor recovery apparatus according to claim 1, wherein it is determined that it is necessary to perform the operation. The depressurization control means includes
When the special time is determined by the transition determining means during the suction inside the adsorption means by the desorption means, the suction inside the adsorption means by the desorption means is terminated halfway, and the unit of degassing gas The vapor recovery apparatus according to claim 1 or 2, wherein the depressurization means performs the depressurization at the special time without limiting the introduction amount per hour so as to suppress the generation of the supply air sound. The depressurization control means causes the depressurization means to perform when the special time is determined by the transition determination means, and does not limit the introduction amount per unit time so as to suppress the generation of the supply air sound. The depressurization means that when the special time is determined by the transfer determining means during the introduction of the depressurizing gas by the depressurizing means, the introduction time of the depressurizing gas is determined by the transfer determining means during the suction by the desorbing means. The vapor recovery apparatus according to any one of claims 1 to 3, wherein an introduction time of the depressurization gas when the special time is determined does not exceed. The amount of introduction per unit time that the depressurization control unit causes the depressurization unit to perform when the normal time is determined by the transition determination unit is limited so as to suppress the generation of the supply air sound. The vapor according to any one of claims 1 to 4, wherein the depressurization increases the amount of depressurization gas introduced per unit time in accordance with the depressurization progress state inside the adsorption means. Recovery device.

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