JPS5839738B2 - Blowout restriction method in high pressure gas transport equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a blowout limiting method for limiting blowout at the end of feeding of a transported object in a high-pressure gas transportation device having a feeding device using a pressurized tank and a separation device.

An example of a high-pressure gas transport device is explained with reference to Fig. 1.
Reference numeral 1 denotes a pressurized tank, into which particles such as fine coal powder, liquid, etc. are filled as objects to be transported through an input port 2 at the upper part of the tank through an input valve 3, and then through a pressure valve 4. The pressure inside the tank is increased by supplying high-pressure carrier gas such as air, and the discharge valve 5
A mixed gas in which the objects to be transported and high-pressure carrier gas are mixed is sent out from the container.

7 is a transport pipe, 8 is a separation device, which is composed of a hotter 9 and a bag filter 10 disposed above it,
The objects to be transported from the bottom of the hopper 9 are transported to the bag filter 10.
The carrier gas is discharged from each of them.

According to this high-pressure gas transport device, as shown in FIG. 2, at time t.

- Fill the pressurized tank 1 with the material to be transported between t1, then open the pressurizing valve 4 as shown by line (P) at time t0 to start increasing the pressure, and discharge at time t2 when this reaches a predetermined pressure. valve 5
Open and start transport.

Then, when all the objects to be transported in the tank are discharged (at time t
3) The pressure loss of the carrier gas in the transport pipeline is reduced, and as a result, the air volume of the carrier gas in the pressurized tank is reduced to a line (
As shown in B), the blowout occurs and the steady value (time t2 to t
In particular, when a pressurized lorry or the like is used as a pressurized tank, the discharge flow rate reaches several times the steady value.

For this reason, the permissible amount of the bag filter 10 must be adapted to the maximum air flow rate at the time of blowout, and an unnecessarily large bag filter has to be used.

The present invention detects the start state of blowout, and accordingly throttles the valve on the transport path to increase the pipe resistance and limit the excessive air flow to the bag filter. The present invention will be described in detail with reference to FIG. 3 and below, using a novel blowout limiting method that prevents an increase in the flow velocity in the channel and suppresses abrasion caused by residual particles and dust, particle crushing, and static electricity generation.

In this example, parts corresponding to those in FIG. 1 are designated by the same reference numerals, and detailed explanation thereof will be omitted.

Reference numeral 21 is an example of a blowout control valve disposed in the middle of the transport pipe 7, and is controlled to close the pipe 7.

An example of this control valve 21 is as shown in FIG.
A valve body 2 having flanges 23 and 24 at both ends thereof.
5, a valve seat 26 arranged on the inner surface of the through hole on the inflow side, and a rotatable valve core 27, which can be used for powder transportation. 27 rotates in the closing direction (direction of arrow A shown in the figure) to perform a squeezing operation, and since there is less granular powder during this squeezing operation, wear can be reduced.

Reference numeral 31 denotes a blowout limit controller that detects the flow rate or flow velocity and is disposed in the gas discharge pipe 11 of the bag filter 10. A blowout detector 32 receives the detection output from the detector 31 and compares it with a predetermined set value. A control output is obtained from the controller 32 when the detected output exceeds a set value, and the control valve 21 is thereby closed.

The above are examples of the first and second inventions of the present invention,
The operation of this method will now be described.

First, the set value of the blowout limit controller 32 is set to the air flow rate at the blowout start time t4 after the time t3 when the steady state transitions to the blowout state, as shown by the broken line in FIG.

Then, when the transportation is finished and the air volume increases, this is detected by the detector 3.
1, and when the detected output exceeds the set value, a control output is obtained from the controller 32, which causes the control valve 21 to rotate from the fully open direction to the closed direction, and the transport pipe 7 is throttled.

As described above, according to the method of the present invention, if a blowout starts after the end of transportation, this is detected and the transportation route is narrowed down, so the flow rate of the carrier gas passing through the bag filter is limited, and compared to the conventional method. It is not necessary to use a bag filter having an unnecessary capacity as in the case of the present invention, and the bag filter can be made smaller and the equipment cost can be reduced accordingly.

Incidentally, even if the pressurized tank 1 is of a type having a discharge valve 5 at the lower part as shown in FIG. 5, blowout control can be performed in the same manner as in the upper part.

Next, a third embodiment of the present invention will be described with reference to FIG.

In this example, the blowout start state is detected as a function of the weight differential value of the pressurized tank, and 41 is a weight detector such as a load cell, and 42 is a control valve 21 based on the output of the detector 41. This control circuit 42 is a control circuit configured to obtain a control output of 1, and the control circuit 42 is such that the weight differential value (weight change) (dw/dt) of the output of the detector 41 is approximately zero, that is, dw/dt
″-i.

It is determined that the tank weight (5) is equal to or less than the minimum set weight (WMIN), and it is also determined that W<wlIIN. When both conditions are satisfied, a control output is obtained and the control valve 21 is configured to be operated from fully open to closed.

According to the embodiment of the third invention described above, it is possible to detect the point in time when the discharge of the transported material in the pressurized tank is completed, and therefore, from that point on, the control valve is activated after a necessary time delay in consideration of the length of the transport pipe. By operating the aperture 21, the same effect as in the above embodiment can be obtained.

In addition, if there is a problem in discharging the transported material from the tank during transportation, even if d w/d tξO, since the tank weight is w > WM engineering N, no control output will be obtained and the control valve will remain open. There is no risk of malfunction.

Next, a fourth embodiment of the present invention will be described with reference to FIG.

In this example, the start of blowout is detected based on a function of the differential pressure at the entrance and exit of the pressurized tank, and in addition to the pressurizing line 51, a booster line 52 is provided to discharge the filling in the tank 1. It is suitable for application to pressurized tanks of the type where the volume is controlled by the difference between pressurized line pressure (Pl) and booster line pressure (P2).

In this type of pressurized tank, the pressure loss is large when the powder is flowing, and the pressure loss is small when the powder is not flowing, so the differential pressure across the discharge valve 5 is detected. The point at which the blowout starts can be detected by
In practice, it is impossible to measure the pressure of paddy immediately before the discharge valve 5 in the tank.For example, in FIG. Differential pressure between 51 and Jistarlife 52 (pt P
2) and the time differential value of pressurization line pressure drop (dP1/d,
) is inserted, and this differential pressure detector 5
3 to find the difference (pt P2) between the pressure line pressure (Pl) and the booster line pressure (P2), P, -P
2 can be approximated to the emission amount dW/dt.

Also, by determining dPl/dt from this differential pressure detector 53, t3. Detecting the drop in pressure P at t4, 2 apt/d,j at K1 (P I P 2 )+
Since the start of blowout can be detected by the lower limit of Kt > O, 2 > 0 (1), the output signal of equation (1) at this time is supplied to the controller 54 and set. The control valve 21 is throttled based on the output.

The blowout start state can also be detected according to the embodiments of the fourth invention described above, and the same effects as those of the embodiments described above can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing a conventional high-pressure gas transport device, Fig. 2 is a diagram showing air volume and pressure to explain its operation, and Fig. 3 is an embodiment of the first and second inventions of the method of the present invention. FIG. 4 is a sectional view showing an example of a blowout control valve, FIG. 5 is a system diagram showing another embodiment of the method of the present invention, and FIG.
FIG. 7 is a system diagram showing an embodiment of the third and fourth aspects of the present invention, respectively. 1 is a pressurized tank, 4 is a pressurization valve, 5 is a discharge valve, 7 is a transportation pipe, 8 is a separation device, 10 is a bag filter, 21 is a blowout control valve, 31 is a blowout detector, 41 is a weight detection 42 is a control circuit, 51 is a pressurizing line, 52 is a booster line, and 53 is a differential pressure detector.

Claims (1)

[Claims] 1. A pressurized tank that stores objects to be transported and sends them out using high-pressure carrier gas, and a separation device that separates the objects to be transported and the high-pressure carrier gas fed from the pressurized tank. In the high-pressure gas transportation device, a blowout start state due to the end of feeding of the material to be transported from the pressurized tank is detected, and the blowout control valve on the transportation path between the pressurized tank and the separation device is thereby throttled. 1. A method for restricting blowout in a high-pressure gas transport device, characterized in that the flow rate in the transport path is restricted by an operation. 2. In a high-pressure gas transport device that has a pressurized tank that stores objects to be transported and sends them out using high-pressure carrier gas, and a separation device that separates the objects to be transported and the high-pressure carrier gas fed from the pressurized tank. Then, the blowout start state due to the completion of feeding of the material to be transported from the pressurized tank is detected by a flow velocity or flow rate detector provided on the high pressure carrier gas discharge side of the separation device, and this detection signal is used to 1. A method for restricting blowout in a high-pressure gas transport device, characterized in that a blowout control valve on a transport pipe between separation devices is throttled to limit the flow rate in the transport pipe. 3. In a high-pressure gas transport device that has a pressurized tank that stores objects to be transported and sends them out using high-pressure carrier gas, and a separation device that separates the objects to be transported and the high-pressure carrier gas fed from the pressurized tank. Then, the blowout start state due to the end of feeding of the material to be transported from the pressurized tank is detected by a function of the weight differential value of the pressurized tank, and this detection signal is used to control the transport path between the pressurized tank and the separation device. 1. A method for restricting blowout in a high-pressure gas transport device, characterized in that the flow rate in the transport path is restricted by throttling a blowout control valve. 4. In a high-pressure gas transport device that has a pressurized tank that stores objects to be transported and sends them out using high-pressure carrier gas, and a separation device that separates the objects to be transported and the high-pressure carrier gas fed from the pressurized tank. Then, the blowout start state due to the end of feeding of the material to be transported from the pressurized tank is detected by a function of the differential pressure at the entrance and exit of the pressurized tank, and based on this detection signal, the transport route between the pressurized tank and the separation device is detected. 1. A method for restricting blowout in a high-pressure gas transport device, characterized in that the flow rate in the transport path is restricted by throttling a blowout control valve.