JP2011194310A - Apparatus for recovering vapor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recover vapor discharged from a plurality of tanks using a single adsorption tank, upon supplying the plurality of tanks with liquid fuel.SOLUTION: There is disclosed an apparatus 10 for recovering vapor, which includes a plurality of underground tanks 20A to 20C, an adsorption tank 30 filled with an adsorbent 32, a vapor recovery route 40, and a control device 50. The control device 50 includes a means 60 of identifying a tank unloading liquid fuel, a means 70 of switching the recovery route 40, and a means 80 of controlling the adsorption tank 30. The means 60 of identifying a tank unloading liquid fuel identifies an underground tank unloading liquid fuel, out of the plurality of underground tanks 20A to 20C. The means 70 of switching the recovery route 40 switches the vapor recovery route 40 to allow the same to communicate with the tank identified by the means 60 of identifying a tank unloading liquid fuel and with the adsorption tank 30 by carrying out the opening/closing control of individual solenoid valves. The means 80 of controlling the adsorption tank 30 controls the flow of vapor discharged via the vapor recovery route 40 switched by the means 70 of switching the recovery route 40, from the tank unloading liquid fuel to feed the vapor into the adsorption tank 30 to allow the adsorbent 32 to adsorb a fuel component contained in the vapor.

Description

  The present invention relates to a vapor recovery device, and in particular, supplies vapor to an adsorption tank filled with an adsorbent, adsorbs the fuel component contained in the vapor with the adsorbent, and then desorbs the fuel component adsorbed on the adsorbent. The present invention relates to a vapor recovery device configured to return to a tank.

  In a fuel supply facility such as a gas station, a tank for unloading liquid fuel from each hatch of a tank truck is installed. This type of tank is mainly buried underground, and the liquid fuel loaded on the tank truck is unloaded via the unloading hose using the height difference from the tank truck.

  In addition, the tank of the gas station is connected to a vent pipe that has a vent that communicates with the atmosphere at a high place. When unloading, the vapor in the tank is discharged into the atmosphere as the liquid level rises. It is configured as follows.

  In recent years, environmental pollution in the atmosphere has become a problem. Therefore, even when unloading, the fuel component (hydrocarbon, which is a main component of petroleum: HC component) contained in the vapor in the tank is recovered and the vapor is in the atmosphere. There is a need to prevent contamination.

  As the vapor recovery device, for example, an adsorbent (for example, silica gel) that adsorbs fuel components contained in the vapor is adsorbed (a process of adsorbing vapor on the adsorbent is referred to as an adsorption process), and the vapor is in the atmosphere. Some are configured to prevent release and to desorb the fuel component adsorbed by the adsorbent (the process of removing vapor from the adsorbent is referred to as a desorption process) and return it to the tank (for example, a patent) Reference 1).

JP 2008-264733 A

  However, conventionally, since the vapor is collected by each vapor collection device by providing a dedicated vapor collection device for each tank, a space for installing a plurality of vapor collection devices is provided on the site of the gas station. There is a problem that the equipment cost increases along with restrictions on the installation space.

  In view of the above circumstances, an object of the present invention is to provide a vapor recovery apparatus that solves the above-described problems.

In order to solve the above problems, the present invention has the following means.
(1) The present invention includes a plurality of tanks in which liquid fuel is unloaded,
An adsorption tank filled with an adsorbent for adsorbing vapor evaporated from the liquid fuel;
A vapor recovery path communicating between the upper space of the plurality of tanks and the air inlet of the adsorption tank;
Unloading tank detecting means for detecting one tank for unloading among the plurality of tanks;
A recovery path switching means for switching the vapor recovery path so as to allow communication between the tank detected by the unloading tank detection means and the adsorption tank;
By being switched by the recovery path switching means, the vapor discharged from the tank being unloaded via the vapor recovery path is supplied into the adsorption tank, and the fuel component contained in the vapor is supplied to the adsorbent. Control means for controlling the flow of vapor so as to be adsorbed;
It is provided with.
(2) The unloading tank detection means of the present invention comprises:
A pressure detector for detecting a pressure change in the tank;
Detection signal output means for outputting a detection signal of the tank when the pressure value detected by the pressure detector becomes a predetermined value or more;
It is characterized by having.
(3) The recovery path switching means of the present invention comprises:
A plurality of on-off valves provided at locations where each of the plurality of tanks communicates with the adsorption tank;
Valve control means for opening an opening / closing valve for communicating the tank in the unloading detected by the unloading tank detection means and the adsorption tank among the plurality of opening / closing valves;
It is characterized by having.
(4) The control means of the present invention includes:
Adsorbing means for controlling the fuel component contained in the vapor to be adsorbed by the adsorbent by supplying the vapor discharged from the tank during unloading into the adsorbing tank;
Gas discharge means for controlling the gas from which the fuel component contained in the vapor has been removed in the adsorption tank to be discharged out of the adsorption tank;
Desorption means for controlling the fuel component to desorb from the adsorbent;
Recirculation means for controlling the fuel component desorbed by the desorption means to recirculate to any of the plurality of tanks;
It is characterized by having.
(5) The recirculation means of the present invention recirculates the fuel component desorbed by the desorption means to a tank that stores the same type of fuel as the fuel component contained in the vapor among the plurality of tanks. To do.

  According to the present invention, the unloading tank detection means detects one tank that performs unloading, switches the vapor recovery path so as to communicate the detected tank and the adsorption tank, and In order to supply the vapor discharged from the tank being unloaded via the vapor recovery path into the adsorption tank and to adsorb the fuel component contained in the vapor to the adsorbent, unloading to one of the tanks At this time, it becomes possible to automatically detect the discharge of the vapor from the one tank and supply the vapor to one adsorption tank. The vapor discharged to the outside of the tank by unloading to each tank The fuel component contained in the vapor can be recovered by supplying it to one adsorption tank and recirculated to one tank, so that the vapor is not released into the atmosphere, preventing environmental pollution during unloading. It is possible, it is possible to reduce the installation space and equipment cost of the adsorption vessel.

It is a system configuration figure showing one example of the vapor recovery device by the present invention. It is a flowchart for demonstrating the vapor | steam collection | recovery control processing which a control apparatus performs. 3 is a flowchart for explaining a control process of a standby process 1; It is a flowchart for demonstrating the control process of an adsorption | suction process. It is a flowchart for demonstrating the control process performed following the control process of FIG. 4A. 5 is a flowchart for explaining a control process of a standby process 2.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a system configuration diagram showing an embodiment of a vapor recovery apparatus according to the present invention. As shown in FIG. 1, the vapor recovery device 10 includes a plurality of underground tanks 20 </ b> A to 20 </ b> C, an adsorption tank 30, a vapor recovery path 40, and a control device 50. The control device 50 includes an unloading tank detection unit 60, a collection path switching unit 70, and an adsorption tank control unit 80.

  In the present embodiment, three underground tanks 20 </ b> A to 20 </ b> C are connected in parallel to one adsorption tank 30 through a vapor recovery path 40. In the present embodiment, the configuration in which three underground tanks 20A to 20C are connected in parallel to one adsorption tank 30 via the vapor recovery path 40 is described as an example. Of course, two or three or more underground tanks may be connected to the adsorption tank 30 in parallel.

  Further, in FIG. 1, the illustration of a measuring machine (oil supply device) that pumps up the liquid fuel stored in each of the underground tanks 20 </ b> A to 20 </ b> C and supplies the fuel tank of the vehicle and the management computer that manages the fueling information by the measuring machine is omitted. ing.

  In the present embodiment, the plurality of underground tanks 20A to 20C are tanks having different capacities such as 20KL, 10KL, and 30KL, and store liquid fuel. Examples of the liquid fuel include regular gasoline, high-octane gasoline, light oil, and kerosene. Here, for convenience of explanation, it is assumed that gasoline is stored in each of the underground tanks 20A to 20C. In addition, the underground tanks 20A and 20B are configured to partition the same tank into two chambers with a partition wall, and are substantially two tanks.

  Each underground tank 20A to 20C is connected to an oil supply pipe 90A to 90C for unloading liquid fuel loaded in a tank truck and a vent pipe 100A to 100C for preventing an increase in tank internal pressure during unloading. Has been. The oil supply pipes 90A to 90C are provided with oil supply ports 92A to 92C to which an unloading hose is connected at the upper end. The vent pipes 100A to 100C have upper ends that extend to high places on the ground, and are provided with breather valves 102A to 102C that open when the tank internal pressure rises above a predetermined pressure and reduce the tank internal pressure to atmospheric pressure. Yes.

  The adsorption tank 30 is formed of a cylindrical container, and is filled with a granular adsorbent 32 that adsorbs fuel components contained in the vapor.

  When the adsorption tank 30 is divided into four blocks in the vertical direction, temperature sensors (temperature detection means) T1 to T4 for measuring the temperature of each block are attached. As the temperature sensors T <b> 1 to T <b> 4, a temperature detection unit made of a thermocouple or the like and having an explosion-proof structure is inserted into the adsorption tank 30. Further, the temperature sensors T <b> 1 to T <b> 4 measure the temperature of the adsorbent 32 filled at different positions in the height direction, and output an electrical detection signal corresponding to the detected temperature to the control device 50. In addition, the number and installation location of a temperature sensor are not restricted to the said number and installation location. Further, as the temperature sensors T1 to T4, a resistance temperature detector, a thermistor, or the like may be used.

  The vapor collection path 40 includes vapor collection pipes 120A to 120C branched from the middle of the vent pipes 100A to 100C, and a vapor collection common pipe 130 that communicates between the vapor collection pipes 120A to 120C and the lower end of the adsorption tank 30. Have Further, the vapor collection pipes 120A to 120C include pressure transmitters PT1 to PT3 for detecting the pressure (vapor pressure) in the gas phase region of each of the underground tanks 20A to 20C, and an electromagnetic valve (open / close valve) for tank selection. V1 to V3 are provided.

  Further, in the vicinity of the adsorption tank 30 of the vapor recovery common pipe 130, an air supply solenoid valve (open / close valve) V4 that is opened when the vapor is recovered is provided.

  The adsorption tank 30 has an exhaust pipe 140 communicated with the upper end. At the upper end of the exhaust pipe 140, an atmospheric valve 150 is provided, and in the middle of the exhaust pipe 140, an electromagnetic valve (open / close valve) V5 is provided as an exhaust valve that is opened during adsorption. The exhaust pipe 140 communicates with a purge branch pipe 160 that bypasses the upstream side and the downstream side of the electromagnetic valve V5. The purge branch pipe 150 is provided with an adsorption tank purge solenoid valve (open / close valve) V6 that is opened during the desorption purge, and an orifice 170 that restricts the flow path.

  Furthermore, one end of a desorption tube 180 is connected to the lower end of the adsorption tank 30. The other end of the desorption tube 180 is connected to the suction side of the vacuum pump 190. The desorption tube 180 is provided with a pressure transmitter PT4 for detecting the pressure of the adsorption tank 30 at the time of desorption, a demounting electromagnetic valve (open / close valve) V7, a first filter 182 and a second filter 184. .

  The reflux pipe 200 connected to the discharge side of the vacuum pump 190 is connected to the upper space (gas phase region) of the underground tank 20B. Since one end of the reflux pipe 200 is connected to the discharge side of the vacuum pump 190, when the desorption process of desorbing the fuel component adsorbed on the adsorbent 32 by vacuum is performed, the desorbed fuel component is removed from the underground tank 20B. The fuel component contained in the vapor can be reused.

  The control device 50 reads each control program stored in the memory, and performs each process (adsorption, adsorption) based on the temperature detected by the temperature sensors T1 to T4 and the pressure value detected by the pressure transmitters PT1 to PT4. Control is performed to open or close the solenoid valves V1 to V7 so that exhaust, desorption, purge, and recirculation) are performed.

  The unloading tank detecting means 60 detects one tank that performs unloading among the underground tanks 20A to 20C. In this embodiment, the pressure transmitters PT1 to PT3 (pressure detectors) that detect pressure changes in the underground tanks 20A to 20C and the pressure values detected by the pressure transmitters PT1 to PT3 are equal to or greater than a predetermined value. And a control program (detection signal output means) for outputting the tank detection signal during unloading.

  In the present embodiment, a case will be described in which it is determined that the tank starts unloading and is being unloaded when the pressure values detected by the pressure transmitters PT1 to PT3 become a predetermined value or more. The means is not limited to the pressure transmitters PT1 to PT3. For example, a sensor or a switch for detecting that the unloading hose of the tank truck is connected to the oil filling ports 92A to 92C is provided, and based on these detection signals. The tank may be configured to determine whether the tank is being unloaded or being unloaded. Or the structure which determines that the said tank is unloading start based on the detection signal from the level gauge provided in each of underground tank 20A-20C instead of pressure transmitter PT1-PT3. It is also good.

  The recovery path switching means 70 performs opening / closing control of each electromagnetic valve so as to switch the vapor recovery path 40 so that the tank detected by the unloading tank detection means 60 communicates with the adsorption tank 30. In the present embodiment, a plurality of electromagnetic valves V1 to V3 provided at locations where each of the underground tanks 20A to 20C communicates with the adsorption tank 30, and an unloading tank detection means 60 among the plurality of electromagnetic valves V1 to V3. A control program (valve control means) for selectively opening any one of the electromagnetic valves V1 to V3 for communicating the detected tank in unloading with the adsorption tank 30;

  The adsorption tank control means 80 supplies the vapor discharged from the tank being unloaded via the vapor collection path 40 switched by the collection path switching means 70 into the adsorption tank 30 and supplies the fuel components contained in the vapor. The electromagnetic valves V1 to V7 are controlled to be opened and closed so as to be adsorbed by the adsorbent 32.

  The adsorption tank control means 80 is a control means (adsorption means 80A, gas discharge means 80B, desorption means 80C, etc.) that performs opening / closing control of the electromagnetic valves V1 to V7 according to each step (adsorption, exhaust, desorption, purge, reflux). Refluxing means 80D). The adsorbing means 80A controls the opening and closing of the electromagnetic valves V1 to V7 so that the vapor discharged from the tank being unloaded is supplied into the adsorption tank 30 and the adsorbent 32 adsorbs the fuel component contained in the vapor. Do. The gas discharge means 80 </ b> B performs opening / closing control of each electromagnetic valve V <b> 1 to V <b> 7 so that the gas from which the fuel component contained in the vapor is removed in the adsorption tank 30 is discharged to the outside of the adsorption tank 30. The desorption means 80 </ b> C communicates with the inside of the adsorption tank 30 and performs opening / closing control of the electromagnetic valves V <b> 1 to V <b> 7 so as to desorb the fuel component from the adsorbent 32. The recirculation unit 80D performs opening / closing control of the electromagnetic valves V1 to V7 so that the desorbed fuel component is recirculated to any of the plurality of underground tanks 20A to 20C.

  Here, control processing executed by the control device 50 will be described. FIG. 2 is a flowchart for explaining the vapor collection control process executed by the control device 50.

  In FIG. 2, the control device 50 stops the vacuum pump 190 in S11 and closes the electromagnetic valves V1 to V7 to set an initial state. In next S12, the control state is set to the standby step 1.

  In next S13, it is checked whether or not the standby process 1 is set. In S13, when the standby process 1 is set (in the case of YES), the process proceeds to S14, and the control process N1 waiting for unloading is executed. In next S15, the control state is set to the adsorption process. Then, it progresses to S16. If the standby process 1 is not set in S13 (NO), the process proceeds to S16.

  In S16, it is checked whether or not the adsorption process is set. In S16, when the adsorption process is set (in the case of YES), the process proceeds to S17, and the control process A of the adsorption process is executed. In next S18, the control state is set to the standby step 2. Then, it progresses to S19. In S16, when the adsorption process is not set (in the case of NO), the process proceeds to S19.

  In S19, it is checked whether or not the control state is set to the standby process 2. In S19, when the control state is set to the standby process 2 (in the case of YES), the process proceeds to S20, and the control process N2 waiting for the metering machine oil supply is executed. In the next S21, the vacuum desorption process is set as the control state. Then, it progresses to S22. In S19, when the control state is not set to the standby process 2 (in the case of NO), the process proceeds to S22.

  In S22, it is checked whether or not the control state is set to the vacuum desorption process. In S22, when the control state is set to the vacuum desorption process (in the case of YES), the process proceeds to S23, and the control process B of the vacuum desorption process is executed. In the next S24, the control state is set to the purge desorption process. Then, it progresses to S25. If the control state is not set to the vacuum desorption process in S22 (NO), the process proceeds to S25.

  In S25, it is checked whether or not the control state is set to the purge / desorption process. In S25, when the control state is set to the purge / desorption process (in the case of YES), the process proceeds to S26, and the control process C of the purge / desorption process is executed. In S25, when the control state is not set to the purge / desorption process (in the case of NO), the process returns to S13 and the processes of S13 to S27 are repeated.

  Next, the control process N1 in the standby process 1 of S14 described above will be described. FIG. 3 is a flowchart for explaining the control process N1 of the standby process 1.

  As shown in FIG. 3, in S31, the electromagnetic valve V7 of the exhaust pipe 140 and the electromagnetic valve V5 of the desorption pipe 180 are opened.

  In the next S32, the timer t4 having the set time 4 set in the standby release timer t4 is started. Subsequently, the process proceeds to S33, in which it is checked whether or not the standby release timer t4 has reached the set time 4. In S33, when the standby release timer t4 has reached the set time 4 (in the case of YES), the process proceeds to S34, and the electromagnetic valve V7 of the exhaust pipe 140 and the electromagnetic valve V5 of the desorption pipe 180 are closed.

  In next S35, the pressure value detected by the pressure transmitter PT1 is read, and it is checked whether or not the pressure in the underground tank 20A is equal to or higher than a preset pressure P1. The set pressure P1 is an arbitrary pressure value set for determining the start of unloading of the underground tank. As an initial setting, for example, 4.5 kPa is set.

  In S35, when the pressure of the underground tank 20A is not equal to or higher than the preset pressure P1 (in the case of NO), since the unloading is not performed in the underground tank 20A, the process proceeds to S36 and is detected by the pressure transmitter PT2. The obtained pressure value is read and it is checked whether or not the pressure in the underground tank 20B is equal to or higher than a preset pressure P1.

  In S36, when the pressure in the underground tank 20B is not equal to or higher than the preset pressure P1 (in the case of NO), since the unloading is not performed in the underground tank 20B, the process proceeds to S37 and detected by the pressure transmitter PT3. The obtained pressure value is read to check whether the pressure in the underground tank 20C has become equal to or higher than a preset pressure P1.

  In S37, when the pressure in the underground tank 20C is not equal to or higher than the preset pressure P1 (in the case of NO), since the unloading is not performed in the underground tank 20C, the process returns to S35, and the processes in S35 to S37 are performed. repeat. Therefore, pressure changes in the underground tanks 20A to 20C are monitored until the fuel loaded in the tank truck is unloaded from any of the underground tanks 20A to 20C.

  In S35 to S37, when the pressure transmitters PT1 to PT3 detect a pressure increase in any of the underground tanks 20A to 20C (in the case of YES), the control process N1 of the current standby process 1 is terminated. To do.

  Next, the control process A of the adsorption process of S20 described above will be described. FIG. 4A is a flowchart for explaining the control process A of the adsorption process. FIG. 4B is a flowchart for explaining a control process executed subsequent to the control process of FIG. 4A.

  As shown in FIG. 4A, in S41, whether or not the pressure value detected by the pressure transmitter PT1 is read and the pressure in the underground tank 20A is equal to or higher than a preset pressure P1 (unloading start determination pressure). Check. In S41, when the pressure in the underground tank 20A is equal to or higher than the preset pressure P1 (in the case of YES), since the unloading is performed in the underground tank 20A, the process proceeds to S42, and the vapor recovery in the underground tank 20A is performed. The electromagnetic valve V1 provided in the pipe 120A is opened.

  In S41, when the pressure in the underground tank 20A is not equal to or higher than the preset pressure P1 (in the case of NO), since the unloading is not performed in the underground tank 20A, the process proceeds to S43, and the pressure transmitter The pressure value detected by PT2 is read, and it is checked whether or not the pressure in the underground tank 20B is equal to or higher than a preset pressure P1 (unloading start determination pressure).

  In S43, when the pressure in the underground tank 20B is equal to or higher than the preset pressure P1 (in the case of YES), since the unloading is performed in the underground tank 20B, the process proceeds to S44 and the vapor recovery in the underground tank 20B is performed. The electromagnetic valve V2 provided in the pipe 120B is opened.

  In S43, when the pressure in the underground tank 20B is not equal to or higher than the preset pressure P1 (in the case of NO), since the unloading is not performed in the underground tank 20B, the process proceeds to S45, and the pressure transmitter The pressure value detected by PT3 is read to check whether or not the pressure in the underground tank 20C is equal to or higher than a preset pressure P1 (unloading start determination pressure).

  In S45, when the pressure in the underground tank 20C is equal to or higher than a preset set pressure (in the case of YES), since the unloading is performed in the underground tank 20C, the process proceeds to S46 and the vapor recovery pipe of the underground tank 20C is obtained. The electromagnetic valve V3 provided at 120C is opened.

  In S45, when the pressure in the underground tank 20C is not equal to or higher than the preset pressure P1 (in the case of NO), since the unloading is not performed in the underground tank 20C, the control process of the present adsorption process Exit A.

  Further, when a pressure increase is detected in any of the underground tanks 20A to 20C by the pressure transmitters PT1 to PT3, it is determined that unloading is started in the underground tank in which the pressure increase is detected. Proceed to S47. In S47, the electromagnetic valve V4 communicated with the lower end side (supply side) of the adsorption tank 30 and the electromagnetic valve V5 communicated with the upper end side (exhaust side) of the adsorption tank 30 are opened. The process of S41 to S46 is an underground tank pressure monitoring process 1 for monitoring the unloading state of each of the underground tanks 20A to 20C.

  By this underground tank pressure monitoring process 1, unloading is performed by selecting one of the solenoid valves V1 to V3 based on the pressure change of the underground tanks 20A to 20C detected by the pressure transmitters PT1 to PT3. The tank is identified, and vapor from the gas phase region of the selected underground tank being unloaded is supplied to the adsorption tank 30.

  In next S48, the set time 1 is set in the suction time timer t1, and the suction time timer t1 is started. The set time 1 is an adsorption time in the adsorption tank 30 and is an arbitrary set time required for completing the unloading of the underground tank (for example, 1 hour in the initial setting).

  Subsequently, in S49, it is checked whether or not the adsorption time timer t1 has reached the set time 1. In S49, when the adsorption time timer t1 has not reached the set time 1 (in the case of NO), the process proceeds to S50, and the underground tank pressure monitoring process 2 of S50 to S55 is executed. Since this underground tank pressure monitoring process 2 is the same as the process of said S41-S46, these description is abbreviate | omitted.

  In S49, when the adsorption time timer t1 reaches the set time 1 (in the case of YES), the process proceeds to S56, and the solenoid valves V1 to V3 are closed to stop the vapor collection, and S50 to S55. End the underground tank pressure monitoring process. Subsequently, in S57, the set time 2 is set in the suction end determination timer t2, and the suction end determination timer t2 is started.

  As shown in FIG. 4B, in the next S58, it is checked whether or not the adsorption end determination timer t2 has reached the set time 2. The set time 2 is an adsorption end determination time for determining whether the adsorption process by the adsorption tank 30 is completed, and according to the capacity of the underground tanks 20A to 20C in order to determine whether or not the underground tank is being unloaded. It is an arbitrary set time (for example, 1 minute in the initial setting).

  In S58, when the adsorption end determination timer t2 has not reached the set time 2 (in the case of NO), the process proceeds to S59, and the underground tank pressure monitoring process 3 in S59 to S64 is executed. Since this underground tank pressure monitoring process 3 is the same as the process of said S41-S46, these description is abbreviate | omitted.

  In S58, when the adsorption end determination timer t2 reaches the set time 2 (in the case of YES), the process proceeds to S65, and it is checked whether or not the electromagnetic valve V1 of the underground tank 20A is opened. In S65, when the solenoid valve V1 of the underground tank 20A is not opened (in the case of NO), the process proceeds to S66, and it is checked whether or not the solenoid valve V2 of the underground tank 20B is opened. In S66, when the electromagnetic valve V2 of the underground tank 20B is not opened (in the case of NO), the process proceeds to S67 and it is checked whether or not the electromagnetic valve V3 of the underground tank 20C is opened.

  In S65 to S67, when any of the solenoid valves V1 to V3 is open (in the case of YES), since the unloading to the underground tank is still continued, the process proceeds to S68, and the adsorption extension timer t3 Is set to a set time 3 and the suction end determination timer t3 is started. It is checked whether or not the suction extension timer t3 has reached the set time 3. The set time 3 is an adsorption extension determination time for determining whether the adsorption process is extended after the adsorption process by the adsorption tank 30 is completed, and is an arbitrary value for extending the determination of whether or not the underground tank is being unloaded. Set time (for example, 30 minutes in the initial setting).

  In the next S69, it is checked whether or not the set time t3 has elapsed. In S69, the unloading to the underground tank is extended until the set time t3 elapses, and the adsorption process by the adsorption tank 30 is also extended. In S69, when the set time t3 has elapsed (in the case of YES), the process proceeds to S70, the solenoid valves V1 to V3 are closed, the vapor collection is stopped, and the vapor collection extension process is terminated.

  In S67, when the solenoid valve V3 of the underground tank 20C is not opened (in the case of NO), the solenoid valves V1 to V3 are all closed, so the process proceeds to S71 and the lower end of the adsorption tank 30 is reached. Then, the solenoid valves V4 and V5 communicated with the upper end are closed, and the vapor recovery (vapor adsorption) is completed. This completes the control process of the adsorption process.

  Next, the control process N2 waiting for the metering machine refueling after the above-described adsorption process of S20 will be described. FIG. 5 is a flowchart for explaining the control process N2 of the standby process 2.

  As shown in FIG. 5, in S81, the pressure value detected by the pressure transmitter PT1 is read to check whether or not the pressure in the underground tank 20A is equal to or higher than a preset pressure P3. The set pressure P3 is an arbitrary pressure value set to determine the free capacity of the underground tanks 20A to 20C, and is set to 0 kPa as an initial set value, for example.

  In S81, when the pressure in the underground tank 20A is not equal to or higher than the preset pressure P3 (in the case of NO), since the unloading is not performed in the underground tank 20A, the process proceeds to S82 and is detected by the pressure transmitter PT2. The obtained pressure value is read to check whether or not the pressure in the underground tank 20B has become equal to or higher than a preset pressure P3.

  In S82, when the pressure in the underground tank 20B is not equal to or higher than the preset pressure P3 (in the case of NO), since the unloading is not performed in the underground tank 20B, the process proceeds to S83 and is detected by the pressure transmitter PT3. The obtained pressure value is read to check whether or not the pressure in the underground tank 20C has become equal to or higher than a preset pressure P3.

  In S83, when the pressure in the underground tank 20C is not equal to or higher than the preset set pressure P3 (in the case of NO), since the unloading is not performed in the underground tank 20C, the process returns to S81, and the processes in S81 to S83 are performed. repeat. Therefore, pressure changes in the underground tanks 20A to 20C are monitored until the fuel loaded in the tank truck is unloaded from any of the underground tanks 20A to 20C.

  In S81 to S83, when the pressure transmitters PT1 to PT3 detect a pressure increase in any of the underground tanks 20A to 20C (in the case of YES), the control process N2 of the current standby process 2 is terminated. To do.

  In the above embodiment, the case where the liquid fuel loaded in the tank truck is unloaded to the underground tank has been described as an example. However, the present invention is not limited to this. For example, the liquid fuel is stored on the ground from the tank in which the liquid fuel is stored. Of course, the present invention can also be applied to the case of supplying to another installed tank.

  Moreover, in the said Example, although the structure which provided the solenoid valves V1-V7 as an on-off valve was illustrated and demonstrated, it is not restricted to this, The opening and closing of the air operation system which opens and closes by supply of air pressure instead of an electromagnetic valve A valve may be used. In addition, when an air-operated on-off valve is arranged at a location where the oil liquid comes into contact, an electrical control signal from the control device is provided by providing an electromagnetic valve for controlling the air pressure in a path for supplying air pressure to each on-off valve. Can be converted into an air signal to control each on-off valve.

DESCRIPTION OF SYMBOLS 10 Vapor collection apparatus 20A-20C Underground tank 30 Adsorption tank 32 Adsorbent 40 Vapor collection path 50 Control apparatus 60 Unloading tank detection means 70 Collection path switching means 80 Adsorption tank control means 80A Adsorption means 80B Gas discharge means 80C Desorption means 80D Reflux Means 90A-90C Lubricating pipes 92A-92C Lubricating ports 100A-100C Ventilation pipes 102A-102C Breather valves 120A-120C Vapor recovery pipe 130 Recovery common pipe 140 Exhaust pipe 150 Air valve 160 Purge branch pipe 180 Desorption pipe 190 Vacuum pump 200 Reflux pipes PT1 to PT3 Pressure transmitters T1 to T4 Temperature sensors V1 to V7 Solenoid valve

Claims (5)

A plurality of tanks in which liquid fuel is unloaded;
An adsorption tank filled with an adsorbent for adsorbing vapor evaporated from the liquid fuel;
A vapor recovery path communicating between the upper space of the plurality of tanks and the air inlet of the adsorption tank;
Unloading tank detecting means for detecting one tank for unloading among the plurality of tanks;
A recovery path switching means for switching the vapor recovery path so as to allow communication between the tank detected by the unloading tank detection means and the adsorption tank;
By being switched by the recovery path switching means, the vapor discharged from the tank being unloaded via the vapor recovery path is supplied into the adsorption tank, and the fuel component contained in the vapor is supplied to the adsorbent. Control means for controlling the flow of vapor so as to be adsorbed;
A vapor recovery apparatus comprising: The unloading tank detection means includes
A pressure detector for detecting a pressure change in the tank;
Detection signal output means for outputting a detection signal of the tank when the pressure value detected by the pressure detector becomes a predetermined value or more;
The vapor recovery apparatus according to claim 1, comprising: The collection path switching means is
A plurality of on-off valves provided at locations where each of the plurality of tanks communicates with the adsorption tank;
Valve control means for opening an opening / closing valve for communicating the tank in the unloading detected by the unloading tank detection means and the adsorption tank among the plurality of opening / closing valves;
The vapor recovery apparatus according to claim 1, wherein: The control means includes
Adsorbing means for controlling the fuel component contained in the vapor to be adsorbed by the adsorbent by supplying the vapor discharged from the tank during unloading into the adsorbing tank;
Gas discharge means for controlling the gas from which the fuel component contained in the vapor has been removed in the adsorption tank to be discharged out of the adsorption tank;
Desorption means for controlling the fuel component to desorb from the adsorbent;
Recirculation means for controlling the fuel component desorbed by the desorption means to recirculate to any of the plurality of tanks;
The vapor recovery apparatus according to any one of claims 1 to 3, further comprising:   The recirculation means recirculates the fuel component desorbed by the desorption means to a tank that stores the same type of fuel as the fuel component contained in the vapor among the plurality of tanks. The vapor recovery apparatus according to any one of the above.

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