JP6829477B2 - Oil-water separator - Google Patents

Description

The present invention relates to an oil-water separation device for improving the oil-water separation capacity by a pneumatic circuit.

Patent Document 1 separates a mixed solution into an aqueous solution and an oil by ensuring a time for the newly introduced mixed solution to separate into the aqueous solution and the oil without stirring. Improve the efficiency of separation. According to the pneumatic circuit 83, the compressed air A3 can be intermittently supplied to the ejector 82 by using only the pneumatic source 83A that constantly applies a constant pneumatic pressure. As a result, the oil ecceptor 51 can intermittently suck up the supernatant L2.

Japanese Unexamined Patent Publication No. 2013-240782

However, in the oil ecceptor 1 of Patent Document 1, (1) the check valve is clogged with oil and cutting powder is clogged with the check valve, so that the check valve does not function, and (2) air is shut off during suction due to negative pressure. Insufficient and sufficient negative pressure cannot be obtained. (3) When the compressor, which is the air pressure source, is stopped, the position of the valve body of the pneumatic circuit does not return to the original position, and the work to return to the original position is complicated. The configuration of the pneumatic circuit is not yet sufficient, and there is a problem that maintenance is complicated and the cost is high.

The problem to be solved by the present invention is to solve the maintenance problem and contribute to cost reduction.

The oil-water separation device of the present invention 1 is a tank that sucks a floating liquid from the surface of a mixed liquid containing an aqueous solution and an oil having a specific gravity smaller than that of the aqueous solution, and a tank that is connected to the pipe to suck and discharge the floating liquid. The pneumatic circuit comprises an oil-water separation tank that collects the floating liquid discharged from the tank and separates it into an oil component and an aqueous solution, and an pneumatic circuit that controls suction and discharge of the floating liquid. The tank, an ejector connected to the air pressure source to generate a negative pressure in the tank, a first-direction control valve that communicates or blocks the flow of the floating liquid from the tank to the oil-water separation tank, and the air pressure. A second-direction control valve that communicates or shuts off the flow of air from the source to the ejector, a time delay valve that performs delayed operation in response to signal pressure, the air pressure source, the time delay valve, and the first. A directional control valve and a relay valve connected to the second directional control valve to switch between suction and discharge are provided, and the first directional control valve and the second directional control valve are from the air pressure source. It is a control 2-port valve that opens and closes the valve by the cylinder operation method by the pilot air. At the time of the suction, the first direction control valve stops the discharge of the floating liquid stored in the tank and the first direction. The flow of air to the tank through the control valve is blocked , the ejector is operated by the second direction control valve to make the inside of the tank negative pressure, and at the time of the discharge, the first direction control valve is used. The floating liquid stored in the tank is discharged, the pressure inside the tank is raised to a predetermined pressure or more by the second direction control valve, the suction time for sucking the floating liquid into the time delay valve, and the above. the floating liquid was set and discharging time for discharging the oil-water separation tank, and that the tank is repeated alternately discharge and suction, at the time of pneumatic stops or when interrupted, the relay valve, the time delay valve, said first 1-way valve, and an oil-water separation apparatus, characterized in that it comprises a return mechanism for returning the valve body of the second directional control valve to the state when the discharge. The predetermined pressure or higher is preferably atmospheric pressure or higher.

The second aspect of the present invention is the oil-water separation device according to claim 1, wherein the return mechanism performs a return operation by a spring or a return operation by air pressure.

According to the third aspect of the present invention, when the tank discharges, the pressure from the relay valve through the throttle valve is supplied to the tank, and the floating liquid is discharged at this pressure. Is.

According to the present invention 1, the burden of maintenance work is burdened by preventing the valve from being clogged, making the air shut off sufficiently at the time of suction by negative pressure, and eliminating the work for returning the valve body to the original position. Can be reduced and the cost can be significantly reduced.

According to the second invention, the maintenance work is greatly improved by performing the return operation of the valve body by the spring or the air pressure.

According to the third invention, the floating liquid is smoothly discharged from the tank, and the discharge efficiency is increased.

It is a block diagram which shows the whole structure of the oil-water separation apparatus of Embodiment 1 of this invention. It is a block diagram (in-situ position, during discharge) which shows the pneumatic circuit of the oil-water separation apparatus of Embodiment 1 of this invention. It is a block diagram (during suction) which shows the pneumatic circuit of the oil-water separation apparatus of Embodiment 1 of this invention. It is a block diagram (during suction / discharge switching) which shows the pneumatic circuit of the oil-water separation apparatus of Embodiment 1 of this invention. It is a block diagram (temporary original position, A tank suction, B tank discharge) which shows the pneumatic circuit of the oil-water separation apparatus of Embodiment 2 of this invention. It is a block diagram (suction / discharge switching) which shows the pneumatic circuit of the oil-water separation apparatus of Embodiment 2 of this invention. It is a block diagram (A tank discharge, B tank suction) which shows the pneumatic circuit of the oil-water separation apparatus of Embodiment 2 of this invention. It is a block diagram (A tank suction, B tank discharge switching) which shows the pneumatic circuit of the oil-water separation apparatus of Embodiment 2 of this invention. It is a block diagram (release of an intermediate stop abnormality) which shows the pneumatic circuit of the oil-water separation apparatus of Embodiment 2 of this invention.

The oil-water separation device 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2. The oil-water separator 1 sucks the floating liquid L2 from the aqueous solution discharged from the machine tool (not shown) and the mixed liquid L1 having a specific gravity smaller than that of the aqueous solution and mixed with oil such as machine oil, and becomes the oil L3. It is separated from the coolant liquid L4 and the coolant liquid L4 is reused. The coolant liquid L4 is an aqueous solution in which a predetermined chemical is dissolved in water, and has a higher specific gravity than the oil content L3.

The oil-water separation device 1 separates the pipe 2 that sucks the floating liquid L2 from the surface of the mixed liquid L1 including air, the tank 3 connected to the pipe 2, and the floating liquid L2 discharged from the tank 3 into an oil component and an aqueous solution. It is provided with an oil-water separation tank 4 (hereinafter referred to as a separation tank 4) for collecting and collecting, and an air pressure circuit 5 (hereinafter referred to as a circuit 5) for controlling the pressure of the tank 3.

The circuit 5 includes an air pressure source 6 (hereinafter referred to as a pneumatic source 6), an ejector 7 that generates a negative pressure in the tank 3, and a control valve 8 provided between the tank 3 and the separation tank 4. , Time delay valves 9A and 9B (hereinafter referred to as valves 9A and 9B) connected to the pneumatic source 6, the pneumatic source 6 and the first direction control valve 8 (hereinafter referred to as control valve 8), and the valve 9A. , 9B is provided with a relay valve 10 and a second direction control valve 11 (hereinafter referred to as a control valve 11).

The relay valve 10 includes a return mechanism 60 that returns the valve body to a predetermined position. The return mechanism 60 performs a return operation by a spring. The compressed air A3 (hereinafter referred to as air A3) intermittently supplied by the circuit 5 is supplied to the ejector 7 by being attached to a machine tool not provided with an actuator. As shown in FIG. 2, the circuit 5 is configured to operate with an air pressure source 6 that constantly applies a constant air pressure. The oil-water separation device 1 operates without using an energy source other than the pneumatic source 6 and regardless of the operating state of the machine tool. Hereinafter, the oil-water separation device 1 will be described in detail.

The structures of the pipe 2, the tank 3, and the separation tank 4 are described in detail in Patent Document 1, so please refer to them. The tank 3 sucks the floating liquid L2 on the liquid surface, temporarily stores it in the tank 3, and discharges it to the separation tank 4. The tank capacity is exemplified by 270 cc.

As shown in FIG. 1, in the storage tank 12, the oil L3 floating near the liquid level 12B is collected from the nozzle 13 provided at the tip of the pipe 2 together with the mixed liquid L1 located below the oil L3. It is sucked up intermittently. The nozzle 13 is connected to the tank 3 via the pipe 2. The suction force of the nozzle 13 increases as the air pressure (hereinafter referred to as pressure) increases.

The circuit 5 controls the ejector 7 by air pressure and intermittently operates it to intermittently operate the suction of the floating liquid L2 and discharge it to the separation tank 4.

The pneumatic source 6 supplies 0.3 MPa to 0.8 MPa of air to the circuit 5. The air supply is turned on and off with a hand valve, and the pressure is preferably around 0.35 MPa. Appropriate pressure is required for constant operation. As the air pressure source 6, a factory air pressure source can be used.

When the pressure is 0.4 MPa, the negative pressure of the ejector 7 is −0.25 to −0.30 MPa, preferably −0.20 to 0.22 MPa.

The ejector 7 is a device that generates negative pressure by utilizing the phenomenon that the compressed air of the pneumatic source 6 is injected from the nozzle at high speed to suck the air around the nozzle and reduce the pressure. The floating liquid L2 can be sucked up by the pressure. The water supply flow rate is exemplified by about 400 cc / min.

The control valves 8 and 11 are 2-port valves for controlling compressed air, and are balanced poppet types capable of forward and reverse flow by adopting a cylinder operating method using pilot air. When pressurizing the port, the pilot air that enters the underside of the piston strokes in a predetermined direction and opens the valve body. When the port is exhausted, the pilot air on the underside of the piston is exhausted, and the return spring closes the valve body and returns it to its original position. Since the control valves 8 and 11 forcibly close the valve body with air, the function of the valve body can be ensured.

The valves 9A and 9B include a first valve body, a differential piston, an exhaust piston, a needle, a return spring, a second valve body, a push rod, and a valve body.

The valves 9A and 9B have a delay time from the input of the signal pressure (hereinafter referred to as a signal) to the output of the signal by the combination of the variable throttle, the variable capacitance and the valve, and when air starts to be supplied, When air is stored and the pressure reaches the upper limit pressure, the variable piston pushes down the rod, the valve opens and the pressurized air passes through. When the air supply is stopped and exhausted, it returns to the same state as before the air supply started.

The valve 9A is set to a discharge time for putting the sucked floating oil into the separation tank 4, for example, usually 20 to 30 seconds. The valve 9B is set with a suction time for sucking the floating liquid L2 from the nozzle 13, for example, 4 seconds to 6 seconds. One cycle is the total value of the discharge time and the suction time, for example, 30 seconds. The discharge time and suction time are set according to the signal. Turning the dial (not shown) clockwise makes it longer, and turning it counterclockwise makes it shorter. The valves 9A and 9B are configured so that the time interval between the start of air supply and the opening of the stored air can be adjusted.

Based on the signal, the relay valve 10 performs a predetermined sequence operation for alternately switching between suction and discharge. Switch to either valve 9A or 9B to send air.

A control valve 11 is arranged between the pneumatic source 6 and the ejector 7 to supply or shut off air to the ejector 7.

As shown in FIG. 1, the pipe 2, the check valve 17, the pipe 14, the tank 3, the pipe 15, the control valve 8, the pipe 16, and the separation tank 4 are connected in this order toward the downstream side. The levitation liquid L2 is a liquid in which a coolant liquid and an oil component are mixed, like the mixed liquid L1.

The pipe 2 is connected to the tank 3 via a check valve 17. The check valve 17 prevents the floating liquid L2, which is intermittently sucked up from the storage tank 12 into the tank 3 and intermittently flows down into the separation tank 4, from flowing back. A control valve 8 is connected between the pipe 15 and the pipe 16. The control valve 8 prevents a decrease in the negative pressure in the tank 3 during the suction time, and ensures discharge at a discharge time other than the suction time.

In FIG. 2, the connection structure of the pipe of the circuit 5 will be described. The pipe 20 connects the valves 9A and 9B and the pneumatic source 6. The pipe 21 connects the valve 9A and the relay valve 10. Pipes 22, 23, and 24 branch from the pipe 20 respectively. The pipe 22 connects the relay valve 10 and the pneumatic source 6. The pipe 23 connects the pipe 20 and the valve 9B. The pipe 24 connects the pipe 20 and the valve 9A. The pipe 25 connects the relay valve 10 and the valve 9B. The pipe 26 connects the throttle valve 27 and the relay valve 10. The throttle valve 27 adjusts the pressure of the air exhausted from the pipe 22 and the valve 10 and applies pressure to the tank 3. The pipe 28 connects the throttle valve 27 and the tank 3. The pipe 29 branches from the pipe 23 and connects to the control valve 11.

The pipe 30 connects the valve 9A and the valve 9B. The pipe 31 branches from the pipe 30 and connects the control valve 8 and the control valve 11, respectively, via the pipes 32 and 33 branching from the pipe 31. The pipe 34 connects the ejector 7 and the control valve 11. The pipe 35 connects the ejector 7 and the tank 3.

The operation of the oil-water separation device 1, mainly the operation of the circuit 5, will be described with reference to FIGS. 1 to 4.

When the pressurized air is started to be supplied from the original position shown in FIG. 2 and the pneumatic source 6 applies the pneumatic pressure to the circuit 5, the discharge mode is entered and the pressure is applied from the pneumatic source 6 to the valve 9A via the relay valve 10. Is supplied. The position of the relay valve in FIG. 2 is the original position. When a signal is applied to the valve 9A via the pipes 20, 22, the relay valve 10, and the pipe 21, the valve body moves after 20 seconds. The valve 9A controls the discharge time of 20 seconds. Since there is no signal on the valve 9B, the valve body does not operate and is open to the atmosphere. Since the control valve 8 is OFF, the floating liquid L2 is discharged, and since the control valve 11 is OFF, the pressure is not supplied to the ejector 7. ON means to push the valve bodies of the control valves 8 and 11 with a signal. OFF means that the valve body is separated by a signal. The floating liquid L2 stored in the tank 3 is discharged to the separation tank 4 via the pipe 15, the control valve 8, and the pipe 16. The air A1 in the tank 3 is opened to the outside air A2 by the ejector 7.

When a signal is supplied to the valve 9A, the pressure is stored in the tank in the valve 9A, gradually increasing the pressure of the air in the tank, the discharge time elapses, the upper limit pressure is reached, and the push rod pushes the valve. Operate the body and communicate signals.

When the discharge time of 20 seconds described above elapses, the discharge mode shown in FIG. 2 is switched to the suction mode shown in FIG. Since the valve body of the valve 9A moves, when a signal is applied to the pipe 30, a signal is applied to the valve 9B, the control valve 11, and the control valve 8. The control valve 8 changes from OFF to ON, and the control valve 11 changes from OFF to ON. The valve body of the valve 9B moves 5 seconds after the signal is applied from the pipe 30 to the valve 9B.

In the suction mode, as shown in FIG. 3, air pressure is supplied to the ejector 7 and the inside of the tank 3 becomes negative pressure. The throttle valve 27 is shut off by the relay valve 10. Since the control valve 8 is ON , the pipe 15 and the pipe 16 are closed. The floating liquid L2 from the storage tank 12 to the tank 3 is sucked into the nozzle 13 together with the air A1 and is sucked up to the tank 3 together with the air A1. In the tank 3, the floating liquid L2 sucked up together and the air A1 are separated, and the floating liquid L2 is stored in the tank 3.

When the suction time of 5 seconds described above elapses, the air pressure stored in the tank of the valve 9B reaches the upper limit pressure, the signal passing through the pipes 20 and 23 is transmitted to the relay valve 10 via the pipe 25, and FIG. The suction mode shown in FIG. 4 is switched to the discharge mode shown in FIG. 2 through the suction / discharge switching state shown in FIG. In the state of FIG. 4, since the valve body of the valve 9B moves, a signal is applied to the relay valve 10 via the pipe 23, the valve 9B, and the pipe 25, and the valve body of the relay valve 10 is the return mechanism 60 of the relay valve 10. Move against. Therefore, the pipe 21 is instantaneously opened to the atmosphere, and the air speed is adjusted by the throttle valve 27 via the pipe 22, the relay valve 10, the pipe 26, and the throttle valve 27, and air pressure is applied to the tank 3. , The tank 3 is instantly pressurized. On the other hand, when the pipe 21 is momentarily opened to the atmosphere, the signal to the valve 9A is stopped, which causes the valves 9A and 9B, the relay valve 10, the control valve 8 and the control valve 11 as shown by the thick arrows in the figure. The spring of each return mechanism 60 of the above is activated to move the valve body, and the return mechanism 60 of each valve returns to the original position and the position during discharge in FIG. Therefore, the valve bodies of the valves 9A and 9B and the relay valve 10 change from the original position, the control valve 8 changes from ON to OFF, and the control valve 11 changes from ON to OFF, respectively. The original positions of the control valves 8 and 11 are in the OFF state.

In this way, the tank 3 switches from discharge and discharge to suction, and switches from suction and suction to discharge, and repeats each process.

When the pneumatic source 6 is stopped or interrupted, the valve bodies of the control valves 8 and 11 are automatically returned to the predetermined positions (original positions).

According to the circuit 5, the air A3 can be intermittently supplied to the ejector 7 by using only the air pressure source 6 that constantly applies a constant air pressure. The oil-water separation device 1 can intermittently suck up the floating liquid L2.

The effect of the oil-water separation device 1 will be described. By adjusting the discharge time and the suction time, it can be changed according to desired conditions. Using the air timers of the valves 9A and 9B, the discharge time and suction time can be adjusted depending on the situation inside the tank 3. This air timer adjusts the time of intermittent operation.

Even if it stops in the middle of operation, the valve bodies of the relay valve 10, the control valve 8, the valves 9A and 9B, and the control valve 11 can be automatically returned to their original positions by the operation of the return mechanism 60. There is an advantage that the accumulated oil does not harden easily.

The oil-water separation device 101 of the second embodiment is an embodiment in which the oil-water separation device 1 is changed to continuous operation, and the relay valve is returned by air instead of the return mechanism 160 by a spring. Regarding the configurations common to each configuration of the oil-water separation device 1, the reference numerals given to the respective configurations are associated with the addition of 100 to the numbers, and detailed description thereof will be omitted. The differences will be mainly described below.

As shown in FIG. 5, the oil-water separation device 101 stops the suction time of the floating liquid L2 and the suction of the floating liquid L2 at the valves 109A and 109B, and discharges the floating liquid L2 to the oil-water separation tank 4 (see FIG. 1). Set the discharge time to be used. A plurality of tanks 103A and 103B, relay valves 110A and 110B, and valves 109A and 109B (here, two) are provided. There is one control valve 111. The relay valve 110B is arranged between the ejector 107 and the tanks 103A and 103B, and is exclusively connected to the two tanks 103A and 103B.

Exclusive connection means that (1) the relay valve 110B connects the tank 103A and the ejector 107 to supply negative pressure and cuts off the connection between the tank 103B and the ejector 107, or (2) the relay valve 110B. Cuts off the connection between the tank 103A and the ejector 107, connects the tank 103B and the ejector 107 to supply negative pressure to the tank 103B, and switches between one of (1) and (2). Say that. The return operation of the valve body is performed by the return mechanism 160 by air pressure.

The shuttle valve 140 of FIG. 5 has two supply ports and one discharge port, and when air pressure is supplied to one supply port, one supply port is closed and flows to the discharge port. It is used for air control and flood control. The shuttle valve 140 has two entrances and one exit, and contains a valve that moves to the left and right so as to close one of the two entrances. An air circuit is built so that air with different pressures can be introduced at each of the two inlets, and the air pressure sent to the valve body is instantly switched from low pressure to high pressure to change the thrust of the valve body.

The valve 150 to which the hand-push button of FIG. 5 is attached releases the relay valve 110A in the case of an intermediate stop abnormality in response to the pressing of the button.

In FIG. 5, the connection structure of the pipe of the circuit 105 will be described. The pipe 120 connects the valves 109A and 109B to the pneumatic source 106. The pipe 121 connects the valve 109A and the relay valve 110A. The pipe 122 branching from the pipe 120 on the way connects the relay valve 110A and the pneumatic source 106. Pipes 123 and 124 branch from the pipe 120. The pipe 123 connects the pipe 120 and the valve 109B. The pipe 124 connects the pipe 120 and the valve 109A. The pipe 125 connects the relay valve 110A and the valve 109B. The pipe 126 connects the pneumatic source 106 and the throttle valve 127. The tube 128 connects the throttle valve 127 and the relay valve 110B. The pipe 129 branches from the pipe 126 and is connected to the control valve 111. The pipe 130 connects the valve 109A and the valve 150. The pipe 131 branches from the pipe 130 and connects to the valve 150. The pipe 132 connects the valve 150 and the pipe 126. The pipe 133A branches from the pipe 125A and connects to the control valve 108A. The pipe 133B branches from the pipe 121 and connects to the control valve 108B. The pipe 134 connects the ejector 107 and the relay valve 110B. The pipe 134A connects the ejector 107 and the control valve 111. The relay valve 110B is connected to the tank 103A and the tank 103B. The pipe 115A connects the tank 103A and the control valve 108A. The pipe 115B connects the tank 103B and the control valve 108B. The pipe 136 branches from the pipe 133B and connects to the inlet of the shuttle valve 140. The pipe 137 branches from the pipe 139 and connects to the inlet of the shuttle valve 140. The pipe 138A branches from the pipe 133A and connects to the relay valve 110B. The pipe 138B branches from the pipe 133B and connects to the relay valve 110B. The pipe 139 connects the relay valve 110A and the valve 109B.

The operation of the oil-water separation device 101, mainly the operation of the circuit 105, will be described with reference to FIGS. 5 to 9. Tanks 103A and 103B operate exclusively. The delay times of the valves 109A and 109B are set to the same time, for example, 7 seconds. When the tank 103A sucks the floating liquid L2, the tank 103B discharges the floating liquid L2.

FIG. 5 shows the in-situ position, A tank suction and B tank discharge. When the pneumatic source 106 applies pneumatic pressure to the circuit 105, a signal is applied to the valve 109B via the pipe 120, the pipe 122, the relay valve 110A, and the pipe 125A, and a suction / discharge time of 7 seconds starts. Valve 109A is open to the atmosphere and is not operating. A signal is supplied to the ejector 7 via the pipe 126, the pipe 129, and the control valve 111, and the inside of the tank 103A becomes a negative pressure. The signal is applied from the pneumatic source 106 to the relay valve 110B via the pipe 126, the throttle valve 127, and the pipe 128, and the inside of the tank 103B is pressurized. Since the control valve 108A is ON, the pipe 115A is closed. Since the control valve 108B is OFF, the pipe 115B is opened. As a result, the floating liquid L2 is sucked from the storage tank 12 into the tank 3 together with the air A1 into the nozzle 113, and is sucked up to the tank 103A together with the air A1 via the pipe 102, the check valve 117A, and the pipe 114A. In the tank 103A, the floating liquid L2 sucked up together and the air A1 are separated, and the floating liquid L2 is stored in the tank 103A. The floating liquid L2 stored in the tank 103B is discharged to the separation tank 4 (see FIG. 1) via the pipe 115B, the control valve 108B, and the pipe 116B.

When the suction / discharge time of 7 seconds described above elapses, the mode changes from the A tank suction / B tank discharge mode shown in FIG. 5 to the A tank discharge / B tank suction mode of FIG. 7 through the switching of FIG. In FIG. 6, the valve body of the valve body 109B operates, and as shown by the arrow, the signal is transmitted from the pneumatic source 106 via the pipes 120, 123, the time delay valve 109B, and the pipe 125, and the valve of the relay valve 110A. By pushing the body, the valve body is activated and the tube 125A is opened to the atmosphere. The signal from the pipe 125A to the valve 109B, the shuttle valve 140, and the pipe 133A disappears, the return mechanism 160, which is a spring, operates, and the control valve 111 is instantaneously shut off. The return mechanism 160 of the control valve 108A works, and the pipe 115A and the pipe 116A switch from shutting off to communicating. After the valve body of the relay valve 110A completes its operation, the state shown in FIG. 7 is reached. In FIG. 7, the signal is applied to the valve 109A via the pneumatic source 106, the relay valve 110A, and the pipe 121. Further, a signal is applied to the relay valve 110B from the pipe 121 via the pipes 121 and 133B and 138B, and the valve body of the relay valve 110B is pushed to operate, so that the relay valve 110B is in the position shown in the drawing. As a result, air pressure is supplied to the tank 103A via the throttle valve 127, the pipe 128, the relay valve 110B, and the pipe 135A. The floating liquid L2 stored in the tank 103A is discharged to the separation tank 4 (see FIG. 1) via the pipe 115A, the control valve 108A, and the pipe 116A. On the other hand, a signal is applied to the control valve 108B, and the pipe 115B and the pipe 116B are switched from communication to shutoff. Pneumatic pressure is supplied to the ejector 107, the inside of the tank 103B becomes negative pressure, and the floating liquid L2 of the storage tank 12 is sucked into the tank 103B.

In this way, in FIG. 7, discharge from the tank 103A and negative pressure suction in the tank 103B are performed. Since the operation of the tanks 103A and 103B is an exclusive operation in which suction and discharge are exchanged, refer to the operation description of FIG.

When the suction / discharge time of 7 seconds described above elapses, the A tank discharge / B tank suction mode shown in FIG. 7 is switched to the A tank suction / B tank discharge mode of FIG.

In the switching operation shown in FIG. 8, the valve body of the valve body 109A operates, and a signal is transmitted from the pneumatic source 106 via the pipes 120, 124, the time delay valve 109A, and the pipe 130 to the valve body of the relay valve 110A. By pushing, the valve body operates and the pipe 121 is opened to the atmosphere. The signal from the pipe 121 to the shuttle valve 140 and the pipe 133B disappears, the return mechanism 160 which is a spring works, and the control valve 111 is instantaneously shut off. Further, the return mechanism 160 of the control valve 108B works, and the pipe 115B and the pipe 116B are switched from the shutoff to the communication. After the valve body of the relay valve 110A has completed its operation, the state shown in FIG. 5 is reached. In FIG. 5, the signal is applied to the valve 109B via the pneumatic source 106, the relay valve 110A, and the pipe 125A. Further, a signal is applied to the relay valve 110B from the pipe 125A via the pipes 125A and 133A and 138A, and the valve body of the relay valve 110B is pushed to operate, so that the relay valve 110B is in the position shown in the drawing. As a result, air pressure is supplied to the tank 103B via the throttle valve 127, the pipe 128, the relay valve 110B, and the pipe 135B. The floating liquid L2 stored in the tank 103B is discharged to the separation tank 4 (see FIG. 1) via the pipe 115B, the control valve 108B, and the pipe 116B. On the other hand, a signal is applied to the control valve 108A, and the pipe 115A and the pipe 116A are switched from communication to shutoff. Pneumatic pressure is supplied to the ejector 107, the inside of the tank 103B becomes negative pressure, and the floating liquid L2 of the storage tank 12 is sucked into the tank 103B.

In this way, the tank 103A alternately switches between discharge and suction, and the tank 103B alternately performs suction and discharge, which is an exclusive operation with the tank 103A.

As shown in FIG. 9, in the case of an intermediate stop in which the suction and discharge operations are stopped in the middle, for example, when the circuit is interrupted due to the intermediate stop of the valve body of the relay valve 110A, the circuit 105 is pushed down by the valve 150. Changes from shutoff to communication, and signal air from the pneumatic source 106 operates the valve body of the relay valve 110A via the pipes 126, 132, 150, 131, 130. As a result, the valve body of the relay valve 110A returns to the original position. Recovery operation can be performed smoothly in the event of trouble such as an emergency stop.

According to the oil-water separation device 101 circuit 105 of the second embodiment, the ejector 107 alternately uses only the air pressure source 106 that constantly applies a constant air pressure to the tank 103A or the tank 103B from the storage tank 12. The floating liquid L2 can be continuously sucked, and the floating liquid L2 stored in the tank 103A or the tank 103B can be alternately and continuously discharged to the separation tank 4 (see FIG. 1). The processing capacity for oil-water separation is greatly improved.

The present invention is not limited to the configurations described in the first and second embodiments, and various modifications, additions, deletions, substitutions, and deletions can be made without changing the gist of the present invention.

Oil-water separator ... 1,101
Tank ... 3,103A, 103B
Oil-water separation tank ... 4
Pneumatic circuit ... 5,105
Pneumatic source ... 6,106
Ejector ... 7,107
1st direction control valve ... 8,108,108A, 108B
Time delay valve ... 9A, 9B, 109A, 109B
Relay valve ... 10,110A, 110B
Valve ... 150
Return mechanism ... 60,160
Check valve ... 17
Liquid level ... 12B
Second direction control valve ... 11,111
Shuttle valve ... 140
Water tank ... 12
Nozzle ... 13
Tubes ... 2,14,15,16,20,21,22,23,24,25,26,
28, 29, 30, 31, 32, 33, 34, 35, 115A, 115B,
116A, 116B, 120, 121, 122, 123, 124, 125,
125A, 126, 128, 129, 130, 131, 132, 133A,
133B, 134,134A, 135A, 135B, 136,137,
138A, 138B, 139
Check valve ... 17, 117A, 117B
Throttle valve ... 27,127
Mixed solution ... L1
Floating liquid ... L2
Oil ... L3
Coolant liquid ... L4
Air ... A1, A2, A3

Claims (3)

A tube that sucks the floating liquid from the surface of the mixed liquid in which the aqueous solution and the oil having a specific gravity smaller than this aqueous solution are mixed,
A tank that connects to the pipe and sucks and discharges the floating liquid,
An oil-water separation tank that collects the floating liquid discharged from the tank and separates it into an oil component and an aqueous solution.
A pneumatic circuit that controls suction and discharge of the floating liquid is provided.
The pneumatic circuit
An ejector that is connected to the tank and an air pressure source and generates a negative pressure in the tank.
A first-direction control valve that communicates or shuts off the flow of floating liquid from the tank to the oil-water separation tank.
A second-direction control valve that communicates or shuts off the flow of air from the air pressure source to the ejector.
A time delay valve that delays operation in response to signal pressure,
The air pressure source, the time delay valve, the first direction control valve, and a relay valve connected to the second direction control valve to switch between suction and discharge are provided.
The first-direction control valve and the second-direction control valve are two-port valves for control that open and close the valves by a cylinder operating method by the pilot air from the air pressure source.
At the time of the suction, the first direction control valve stops the discharge of the floating liquid stored in the tank and shuts off the flow of air to the tank through the first direction control valve to control the second direction. Activating the ejector with a valve to create a negative pressure inside the tank.
At the time of the discharge, the floating liquid stored in the tank is discharged by the first direction control valve, and the pressure inside the tank is raised to a predetermined pressure or more by the second direction control valve.
A suction time for sucking the floating liquid and a discharge time for discharging the floating liquid to the oil-water separation tank are set in the time delay valve, and the tank alternately repeats suction and discharge.
When air pressure is stopped or during interruptions, the relay valve, the time delay valve, said first directional control valve, and includes a return mechanism for returning the valve body of the second directional control valve to the state when the discharge An oil-water separator characterized by this. The oil-water separation device according to claim 1, wherein the return mechanism performs a return operation by a spring or a return operation by air pressure. The oil-water separation device according to claim 1 or 2, wherein when the tank discharges, the pressure from the relay valve through the throttle valve is supplied to the tank, and the floating liquid is discharged at this pressure.