TWI629091B - Vapor recovery device - Google Patents

Abstract

The present invention provides a vapor recovery device which prevents aspiration of fuel and prevents breakage of the vapor recovery device. The vapor recovery device is a condenser having a vapor recovery line disposed at one end of the underground tank and attracting the fuel vapor inside the underground tank, and a condenser connected to the downstream side of the compression pump and condensing the fuel vapor. And recovering the fuel vapor inside the underground tank, and having: a buoy switch disposed on the upstream side of the compression pump and detecting the fuel flowing through the vapor recovery line, and an on-off valve according to the detection result of the buoy switch Interrupting valve. The buoy switch utilizes fuel in the housing to detect the inflow of fuel as the buoy rises to a predetermined position.

Description

Vapor recovery unit Field of invention

The present invention relates to a vapor recovery device that recovers fuel vapor (vaporized fuel) retained in an underground tank when the fuel is discharged from the tanker toward the underground tank.

Background of the invention

In general, the fuel such as gasoline is highly volatile. Therefore, when the fuel is unloaded from the tanker in the underground tank buried in the gas station, the fuel vapor volatilized in the upper space of the underground tank will remain. . In the past, the above-mentioned fuel vapor was released into the atmosphere through a vent pipe connected to the underground tank.

However, when fuel vapor is released into the atmosphere in this state, it is not only a waste of resources, but also environmental pollution caused by fuel vapors released from the atmosphere, and the ignition of fuel vapors released into the atmosphere. There is a problem with the fire.

Therefore, in order to solve the above problems, the applicant has proposed a vapor recovery device that liquefies and reuses fuel vapor in Patent Documents 1 and 2. The oil supply device described in Patent Document 1 is provided with a condensing device for liquefying fuel vapor and recovering liquefied gasoline, and a condensing device for use in the device. The gasoline vapor that is not recovered can absorb and remove the gasoline component, so that the recovery of liquefied gasoline can be effectively carried out.

On the other hand, in the oil supply device described in Patent Document 2, the fuel vapor is recovered through a vapor return pipe provided in the vicinity of the fuel supply nozzle, and the vapor is cooled by using a cooling suction device, and then separated into a vapor by a gas-liquid separation tank. Gas, gasoline, and water made up of air.

Advanced technical literature Patent literature

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2006-198604

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2014-19474

Summary of invention

However, the invention described in the above Patent Documents 1 and 2 has an effective function. However, when the vapor recovery device is additionally provided to the already installed gas station, the fuel vapor is not directly recovered in the oil supply device, but Temporary recovery is carried out in an underground tank buried in the underground of the gas station, and the vapor recovery device is used to attract fuel vapor from the underground tank.

At this time, the vapor recovery device recovers the fuel vapor in the underground tank through the piping and uses the compression pump, but the overflow of the fuel supplied to the underground tank or more in the unloading, or the failure of the sensor in the underground tank, etc. For some reason, when the fuel is over-injected into the underground tank, there is a vapor recovery device that attracts fuel.

Here, the compression pump installed in the device is a steam (gas) Therefore, as described above, when the vapor recovery device attracts fuel, there is a problem that the compression pump is broken.

Accordingly, the present invention has been made in view of the above problems of the prior art, and an object thereof is to provide a vapor recovery device which can prevent fuel from aspiration and protect a compression pump or the like.

In order to achieve the above object, the present invention has a suction mechanism provided in a pipe connected to one end of the underground tank, and sucks fuel vapor inside the underground tank; a condensation mechanism is connected to the downstream side of the suction mechanism, so that The vapor recovery device for recovering the fuel vapor in the underground tank; and the vapor recovery device for recovering the fuel vapor inside the underground tank, further comprising: a liquid detecting mechanism provided on an upstream side of the suction mechanism, detecting inflow through the pipeline The fuel; the valve switching mechanism switches the valve based on the detection result of the liquid detecting mechanism.

According to the invention, the liquid detecting means is provided on the upstream side of the suction means such as the compression pump, and the valve is opened and closed by the valve switching mechanism based on the detection result of the liquid detecting means, so that the fuel mixed with the fuel vapor is Before the compression pump is attracted, the fuel can be detected and mixed, and the compression pump can be prevented from being damaged.

In the above vapor recovery device, the liquid detecting means includes: a buoy that rises and lowers according to a liquid level of the fuel in the casing; and a first pipe that is connected to the casing and introduces the fuel vapor and/or the fuel; and a pipe connected to the casing and disposed above the first pipe and connected to the valve switching mechanism; and, by using the fuel in the casing, the floating When the target rises to a predetermined position, the inflow of the aforementioned fuel can be detected. Thereby, even if the fuel is mixed, the outflow to the downstream side of the fuel can be prevented.

In the vapor recovery device described above, the liquid detecting means may be provided with a drain cock that discharges fuel in the casing from the bottom surface of the casing.

As described above, according to the present invention, it is possible to prevent the fuel from being sucked up and to protect the device such as the compression pump.

1‧‧‧Vapor recovery unit

2‧‧‧ Underground trough

3‧‧‧Measuring machine

3a‧‧‧Blower pump

4‧‧‧ fueling island

5‧‧‧Vapor piping

6‧‧‧Vapor recovery line

7‧‧‧Liquid return line

8‧‧‧ snorkel

9‧‧‧Water return line

10‧‧‧ gas station

11‧‧‧ buoy switch

11a‧‧‧Shell

11b‧‧‧Main trunk

11c‧‧‧ buoy

11d‧‧‧lower brake

11e‧‧‧Upper brake

11f‧‧‧Vapor suction port

11g‧‧‧Vapor discharge

11h‧‧‧ gasoline liquid discharge

11i‧‧‧Draining cock

12‧‧‧Interruption valve

13‧‧‧Switching valve

14‧‧‧Compressed pump

15‧‧‧Condenser

16‧‧‧ gas-liquid separation tank

17‧‧‧Liquid return valve

18‧‧‧Water return valve

19‧‧‧Switching valve

20‧‧‧High concentration device

21‧‧‧vacuum pump

22‧‧‧ Pressure regulating valve

[Fig. 1] is a schematic view showing an example of the overall configuration of a gas station including an embodiment of the vapor recovery device of the present invention, and is a view including an enlarged portion of a schematic important portion of the vapor recovery device.

Fig. 2 is a schematic view showing an example of a configuration of a buoy switch.

FIG. 3 is a flow chart for explaining a flow of a process of a vapor recovery device when a flow pulse can be obtained from a weighing machine.

FIG. 4 is a flow chart for explaining a flow of a process of a vapor recovery device when a flow pulse cannot be obtained from a weighing machine.

Next, the form for carrying out the invention will be described in detail with reference to the drawings.

As shown in Fig. 1, the gas station 10 is provided with a plurality of fueling islands 4, 4, ..., each of which is provided with a measuring machine 3, 3, .... The predetermined fueling island 4 is provided with the vapor recovery device 1 of the present invention. Further, the underground tank 2 is buried in the underground of the gas station 10, and the weighing machine 3 and the vapor recovery device 1 on each of the fueling islands 4 are connected by various pipes. The underground trough 2 is further connected to the ground The vent pipe 8 is extended, and the vent pipe 8 is provided with a vent valve (not shown) that opens when the pressure of the gas layer portion of the underground tank 2 becomes equal to or higher than a predetermined pressure (abnormal pressure).

The measuring machine 3 is connected to the underground tank 2 through a steam pipe 5. In each of the measuring machines 3, the gasoline vapor (gasified gasoline) which is generated as fuel vapor when the gasoline or the like is supplied to the vehicle is recovered by the blower pump 3a provided in each of the measuring machines 3, and is permeable to the steam. The pipe 5 is returned to the gas layer portion of the underground tank 2.

The vapor recovery device 1 is connected to the underground tank through the vapor recovery line 6 and the liquid return line 7, and is passed through the vapor recovery line 6, and the gasoline vapor present in the gas layer portion of the underground tank 2 is sucked and recovered and separated into liquefied gasoline and the atmosphere ( Air), and the liquefied gasoline is returned to the liquid layer portion of the underground tank 2 through the liquid return line 7.

In detail, the vapor recovery device 1 has a buoyant switch 11, a shutoff valve (solenoid valve) 12, a compression pump 14, a condenser 15, a gas-liquid separation tank 16, a high concentration device 20, and a vacuum pump. twenty one.

The vapor recovery line 6 is connected to the underground tank 2 at one end thereof, and is connected to the buoy switch 11 at the other end. The buoy switch 11 is connected to the vapor recovery line 6 on the upstream side, and the shutoff valve 12 is connected to the downstream side. The buoy switch 11 passes through the vapor recovery line 6 to detect the gasoline liquid mixed into the gasoline vapor that has been collected and recovered.

The shutoff valve 12 is connected to the buoy switch 11 on the upstream side, and the switching valve 13 is connected to the downstream side. The shutoff valve 12 is, for example, a solenoid valve, and switches the valve based on the detection result of the gasoline liquid of the buoy switch 11. Interrupting valve 12 It is normally turned on when the device is in operation, and is turned off when the buoy switch 11 has a predetermined amount of gasoline liquid mixed in.

As shown in FIG. 2, the buoy switch 11 has a buoy 11c provided in the trunk 11b in the casing 11a, and a lower limit brake 11d for detecting the lower limit amount of the gasoline liquid in the casing 11a, for detecting the casing 11a. The upper limit brake 11e of the upper limit of the amount of the gasoline liquid, the vapor suction port 11f provided on the side surface of the casing 11a and sucking the gasoline vapor, and the side surface of the casing 11a are located above the vapor suction port 11f to discharge the gasoline vapor and guide The vapor discharge port 11g to the shutoff valve 12, the gasoline liquid discharge port 11h which is provided on the bottom surface of the casing 11a and which is mixed with the gasoline vapor and which is discharged to the outside in the casing 11a, and the discharge of the gasoline liquid discharge port 11h of the discharge of the gasoline liquid draining cock 11i.

The gasoline liquid is mixed in from the vapor suction port 11f, and as the level of the gasoline liquid in the casing 11a rises, the buoy 11c rises. Further, when the buoy 11c comes into contact with the upper limit brake 11e, the incorporation of the gasoline liquid is detected. Thereby, the buoy switch 11 is turned on, and the shutoff valve 12 is closed.

The buoy 11c is lowered to the position of the lower limit stopper 11d by opening the drain cock 11i and discharging the gasoline liquid in the casing 11a to the outside. Thereby, the shutoff valve 12 can be opened by releasing the ON state of the buoy switch 11 and turning it off. Further, in order to open the shutoff valve 12, for example, the vapor recovery device 1 must be reset.

Referring back to FIG. 1, the switching valve 13 is connected to the upstream side of the shutoff valve 12, the other upstream side to which the vacuum pump 21 is connected, and the downstream side to which the compression pump 14 is connected.

The compression pump 14 draws the gasoline vapor back through the vapor recovery line 6. The gasoline vapor that has been collected and recovered is discharged to the condenser 15 which will be described later. The condenser 15 draws out the liquefied gasoline and water by cooling and condensing the gasoline vapor discharged from the compression pump 14.

When the gasoline vapor is liquefied, it can be carried out, for example, by using a cooling mechanism from the outside or by circulating the gasoline itself internally. Also, part of the gasoline vapor is not liquefied to become residual vapor. The liquefied gasoline, water, air, and residual vapor extracted by the condenser 15 are guided to the gas-liquid separation tank 16.

The gas-liquid separation tank 16 separates the gas composed of the liquefied gasoline, the water, the air, and the residual vapor guided by the condenser 15 and retains the liquefied gasoline and the water in a different specific gravity, and the air and the air are separated. The residual vapor is guided to a high concentration device 20 to be described later.

The liquefied gasoline remaining in the gas-liquid separation tank 16 is guided to the liquid return line 7 through the liquid return valve 17 as long as it remains in a predetermined amount, and is discharged toward the underground tank 2. When the water remaining in the gas-liquid separation tank 16 is stored for a predetermined amount, it is guided to the water return line 9 through the water return valve 18 and discharged to the outside.

The switching valve 19 is connected to the gas-liquid separation tank 16 on the first upstream side, and the high-concentration device 20 is connected to the first downstream side on the second upstream side, and the vacuum pump 21 is connected to the second downstream side. The switching valve 19 guides the air and the residual vapor which are guided from the gas-liquid separation tank 16 to the first upstream side to the first downstream side to be guided to the high-concentration device 20.

The high concentration device 20 increases the concentration of residual vapor and discharges it. The residual vapor discharged from the high concentration device 20 passes through the second of the switching valve 19 The upstream side and the second downstream side are guided to the vacuum pump 21. Further, the high-concentration device 20 passes through the pressure regulating valve 22 to adjust the pressure of the air and discharges the air to the atmosphere.

The vacuum pump 21 is connected to the switching valve 19 at one end thereof and the switching valve 13 to the other end. The vacuum pump 21 attracts the residual vapor which has been highly concentrated, and discharges it toward the switching valve 13 side.

Next, the operation of detecting the buoy switch 11 in which the gasoline liquid is mixed with the gasoline vapor will be described with reference to FIG. 2 . First, in normal times, the buoy switch 11 is in an OFF state, and the shutoff valve 12 is in an open state. In this state, when the gasoline vapor mixed with the gasoline liquid is sucked and injected into the casing 11a through the vapor suction port 11f, the gasoline vapor is discharged through the steam discharge port 11g, and on the other hand, the gasoline liquid that has been mixed therein It will remain in the casing 11a.

The buoy 11c rises according to the level of the gasoline liquid in the casing 11a. When the buoy 11c rises to the position of the upper limit brake 11e and comes into contact with the upper limit brake 11e, the buoy switch 11 is turned to the ON state, whereby the shutoff valve 12 is instantaneously closed, and the operation of the vapor recovery device 1 is stopped.

Here, in the buoy switch 11, the vapor discharge port 11g from which the gasoline vapor is discharged is located above the vapor suction port 11f. Therefore, even when the gasoline vapor is mixed with the gasoline vapor, the gasoline liquid is not discharged through the vapor discharge port 11g. Therefore, the gasoline liquid can be prevented from flowing into the subsequent stage of the buoy switch 11, and the damage of the compression pump 14 can be prevented.

When the vapor recovery device 1 is stopped, the drain cock 11i is operated to discharge the gasoline liquid in the casing 11a through the gasoline liquid discharge port 11h, and the buoy 11c is lowered from the position of the upper limit brake 11e to release the buoy switch 11 In the ON state, the vapor recovery device 1 is further reset, whereby the vapor recovery device 1 can be restored.

Next, the operation of mixing the gasoline vapor in the vapor recovery device 1 when the gasoline vapor is recovered and liquefied will be described with reference to FIGS. 3 and 4 .

First, the flow of the process of the vapor recovery device 1 when the flow pulse can be obtained from the weighing machine 3 will be described with reference to FIG. 3. In the vapor recovery device 1, when the gasoline vapor is sucked and recovered, the fuel supply state of the weighing machine 3 can be determined. However, in this example, the fuel supply state is determined based on the flow rate pulse obtained from the weighing machine 3.

In step S1, it is possible to determine the presence or absence of a flow pulse. When the flow pulse has been generated (step S1; Yes), the compression pump 14 and the vacuum pump 21 are turned ON to perform suction recovery of the gasoline vapor (step S2). On the other hand, when the flow pulse is not generated (step S1; No), the series of processes ends.

In step S3, it can be judged whether or not the buoy switch 11 is ON. When it is judged that the gasoline liquid in the casing 11a reaches the predetermined amount and the buoy switch 11 is ON (step S3; Yes), the shutoff valve 12 is closed, and the compression pump 14 and the vacuum pump 21 are turned OFF, and the gasoline vapor is stopped. The attraction is recovered (step S4). On the other hand, when it is judged that the buoy switch 11 is OFF (step S3; No), the processing returns to step S1.

In step S5, it can be judged whether or not the buoy switch 11 is OFF. When it is judged that the buoy switch 11 is OFF (step S5; Yes), the reset processing for the vapor recovery device 1 is performed. Thereby, the vapor recovery device 1 can be initialized, and the buoy switch 11 is restored and turned ON. On the other hand, when it is judged that the buoy switch 11 is ON (step S5; No), the process of step S5 is repeated until the buoy switch 11 becomes Until OFF.

Next, the flow of the process of the vapor recovery device 1 when the flow rate pulse cannot be obtained from the weighing machine 3 will be described with reference to FIG. 4 . In this example, the vapor recovery device 1 determines the fuel supply state based on a signal indicating the state of the fuel supply pump that can be obtained from the weighing machine 3.

In step S11, it can be judged whether or not the oil supply pump is ON. When it is judged that the fuel supply pump is ON (step S11; Yes), the compression pump 14 and the vacuum pump 21 are turned ON to perform suction recovery of the gasoline vapor (step S12). On the other hand, when it is judged that the fuel supply pump is not ON (step S11; No), the series of processes ends.

In step S13, it can be determined whether or not the buoy switch 11 is ON. When it is determined that the gasoline liquid in the casing 11a reaches the predetermined amount and the buoy switch 11 is ON (step S13; Yes), the shutoff valve 12 is closed, and the compression pump 14 and the vacuum pump 21 are turned OFF, and the gasoline is stopped. The vapor is recovered and recovered (step S14). On the other hand, when it is judged that the buoy switch 11 is OFF (step S13; No), the processing returns to step S11.

In step S15, it can be judged whether or not the buoy switch 11 is OFF. When it is judged that the buoy switch 11 is OFF (step S15; Yes), the reset processing of the vapor recovery apparatus 1 is performed. Thereby, the vapor recovery device 1 can be initialized, and the buoy switch 11 is restored and turned ON. On the other hand, when it is judged that the buoy switch 11 is ON (step S15; No), the process of step S15 is repeated until the buoy switch 11 is turned OFF.

As described above, according to the present embodiment, in the preceding stage of the compression pump, the gasoline liquid is detected to be mixed with the gasoline vapor, and the gasoline liquid that has been mixed is reached. When the predetermined amount is turned off, the operation of the apparatus is stopped by closing the shutoff valve, so that the gasoline liquid can be prevented from flowing into the apparatus and the damage of the compression pump due to the gasoline liquid can be prevented.

Claims (3)

A vapor recovery device comprising: a suction mechanism, a pipeline connected to an underground tank at one end, and attracting fuel vapor inside the underground tank; a condensation mechanism connected to a downstream side of the suction mechanism to condense the fuel vapor And a vapor recovery device for recovering fuel vapor inside the underground tank, further comprising: a liquid detecting mechanism provided on an upstream side of the suction mechanism to detect fuel flowing in through the pipeline; and a valve switch The mechanism switches the shutoff valve based on the detection result of the liquid detecting mechanism. The vapor recovery device of claim 1, wherein the liquid detecting mechanism has: a buoy that is raised and lowered according to a liquid level of the fuel in the housing; and a first conduit connected to the housing and introduced into the fuel vapor and/or the foregoing And the second pipeline is connected to the casing and disposed above the first pipeline and connected to the valve switching mechanism; and, when the fuel in the casing is raised, the buoy is raised to a predetermined position The inflow of the aforementioned fuel is detected. The vapor recovery device of claim 2, wherein the liquid detecting mechanism has a drain cock that discharges fuel in the housing on a bottom surface of the housing.