JPS6341808B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a powder distributing and transporting device that connects a plurality of transport pipes to one pressurized tank and distributes and transports the powder and granular material in the pressurized tank.

JP-A-56-52321 has been proposed as a device for distributing and transporting powder and granular materials directly from one pressurized tank to multiple receiving ends via multiple transport pipes. Although it is applicable in some cases, if the length of the transport pipes differs, accurate distribution and transport is difficult due to pipe resistance and the like.

Furthermore, this device detects the differential pressure between the pressurized gas pressure and the pressure inside the transport pipe as a guide for manually adjusting the booster flow rate, but since the inside of the transport pipe contains powder and granules, there is a lot of noise and this is difficult to detect when transporting a high solid-air ratio. was accompanied by something inappropriate.

Furthermore, this device does not control the pressure in the pressurized gas chamber below the fluidized bed, so there is a disadvantage that adjustment work for fluctuations in flow rate cannot be performed quickly and easily.

Furthermore, not only in distributed transportation but also in gas transportation, particles can become clogged in the transport pipe due to adhesion of powder or granules to the inner wall of the transport pipe, decrease in flow velocity, high solid-air ratio transport, or other causes. easy.

For this reason, although attempts have been made to monitor the blockage of each transport pipe by detecting the transport pipe differential pressure in the conventional apparatus described above, this apparatus cannot make a reliable determination.

In other words, when some of the many transport pipes are blocked, even if the transport gas from the transport gas supply pipe connected to the transport pipe flows back into the pressurized tank, the transport gas continues to be transported normally. Because it escapes to the outside through other transport pipes, the pressure inside the pressurized tank does not noticeably increase, and blockage detection is delayed, causing the powder and granules stuck in the transport pipe to be compressed with the transport gas, making the blockage even worse. Sometimes it gets worse.

The present invention maintains the flow bed pressure chamber pressure constant and controls the distribution ratio according to the flow rate of each booster, detects a transport pipe that is likely to cause a blockage in this state, and immediately removes the transport pipe. At the same time as disconnecting from the system, in order to eliminate the reaction to the pressurized tank and other transport pipes, a transport valve that is fully open during transport is installed near the tank side of each transport pipe, and a supply source valve is interposed in each gas supply pipe. These are simultaneously controlled by the differential pressure between the pressure chamber pressure and the booster line pressure.

Embodiments of the apparatus of the present invention will be described below with reference to the drawings.

In the figure, 1 is a pressurized tank having a powder input valve 2 at the top and a fluidized bed 3 at the bottom, and 4 is a pressurized gas supply pipe that supplies pressurized gas to the fluidized bed 3. A pressure regulating valve 5 is interposed in the supply pipe 4, and this regulating valve 5 detects the pressure at the position of the fluidized bed 3 with a pressure detector 6, and supplies it to a pressure regulator 7.
The pressure in the fluidized bed section is maintained at a desired value by the output of the fluidized bed section.

T _N (N is an integer of 2 or more) is a transport pipe connected to the pressurized tank 1, and its opening 9 extends into the pressurized tank 1 and is closely opposed to the fluidized bed 3. VT _N is a transport valve installed outside the pressurized tank 1 of each transport pipe T _N , and is operated to be fully open during transport and fully closed when not transporting.

B _N is a transport gas supply pipe connected to the secondary side of the transport valve VT _N of each transport pipe T _N , and a flow rate regulating valve VF _N and a flow rate detector FD _N are interposed in each pipe to detect the flow rate. The detection signal of the controller FD _N is supplied to the flow controller FC _N , and the output of this controller FC _N controls the flow rate control valve.
VF _N is operated to maintain the transport gas flow rate at the required value.

On the other hand, the detection signal of the pressure detector 6 and the detection signal of the pressure detector PB _N disposed near the transport pipe T _N of each transport gas supply pipe B _N are supplied to the differential pressure regulator △PC _N. The flow rate controller FC _N is cascade controlled by the output of this controller △PC _N , and each transport pipe
The flow rate of the T _N powder or granular material is adjusted to be uniform or to have a required distribution ratio. That is, transport pipe
When the powder flow rate in T _N decreases, the differential pressure decreases,
Conversely, when the powder flow rate increases, the differential pressure increases, so in the former case, operate the flow rate control valve VF _N in the direction of opening to increase the transport gas flow rate and decrease the powder cutout amount, and in the latter case In the opposite case, the flow rate control valve VF _N is operated in the direction of closing to decrease the transport gas flow rate and increase the amount of powder material cut out.

CP _N is a comparator to which the output of the differential pressure controller △PC _N is supplied, and when the output of the controller △PC _N increases from the required setting value, that is, when the differential pressure △P _N decreases from the required value. A comparison output SC is obtained, which is supplied to an alarm circuit AR _N such as a buzzer flashing indicator to issue an alarm and close the supply source valve VBN and transport valve VTN installed in the transport gas supply pipe.

Next, the operation of the apparatus of the present invention described above will be explained. First, the pressurized tank 1 is filled with powder and granular material via the charging valve 2 with the transport valve VT _N closed, and then the charging valve 2 is closed and the The pressure control valve 5 is opened and pressurized gas is supplied to the fluidized bed 3 to increase the pressure inside the pressurized tank to a predetermined value.

Next, by opening the main valve VB _N and then fully opening the transport valve VT _N , the powder and granules in the tank 1 are sent into the transport pipe T _N according to the transport gas flow rate QB _N , and transport to the destination begins. be done.

Therefore, in a steady state of transportation, a differential pressure △P _N corresponding to the amount of powder material cut out occurs in the transport pipe T _N , and this is supplied to the differential pressure controller △PC _N , so that the differential pressure △P _N The flow controller FC _N is cascade-controlled so that the constant value is maintained, and the powder is transported at a constant flow rate.

When the transport pipe T _N is blocked by powder or granules in a steady state of transport, the differential pressure of the blocked transport pipe T _N becomes smaller than the steady state differential pressure △P _A , as shown in Figure 2. It decreases rapidly at the occlusion point ts. For this reason, the output of the differential pressure regulator △PC _N increases, so a comparison output SC is obtained from the comparator CP _N , and the alarm circuit AR _N is activated to notify the blockage state and to cause the blockage to occur. The transport valve VT _N and main valve VB _N of the system are completely closed, and the supply of powder and granular material and transport gas to the transport pipe T _N is immediately stopped, so the transport gas does not flow back into the pressurized tank. In addition, the powder and granules at the blockage position are not compressed by the transport gas, making it easy to remove the clogged powder and granules. It has characteristics such as being able to perform

In each of the above embodiments, the case was explained in which the output of the differential pressure regulator △PC _N was supplied to the comparator CP _{N, but the outputs of the pressure detector 6 and PB N were} supplied to the subtracter. Even if the output of this subtracter is supplied to a comparator, the same effect as in the above example can be obtained.

The present invention maintains the pressure in a fluidized bed pressurizing chamber constant and controls the transport gas flow rate by the differential pressure output between this pressure and the transport gas pressure near the transport pipe, and distributes and transports the powder and granules. Each transport gas supply source valve and the transport valve of the transport pipe connected thereto are automatically closed based on the abnormal comparison output between the pressure output and the set value. It is played.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing an embodiment of the device of the present invention;
FIG. 2 is a graph showing the differential pressure in the transport pipe to provide an explanation thereof. 1... Pressurized tank, 3... Fluidized bed, 6... Pressure detector, T _N ... Transport pipe, B _N ... Transport gas supply pipe,
△PC _N ...Differential pressure controller, PB _N ...Pressure detector,
VT _N ...transport valve, VB _N ...main valve, CP _N ...comparator.

Claims (1)

[Claims] 1 A pressurized tank equipped with a pressurized gas chamber for flow has a plurality of discharge nozzles connected to a plurality of transport pipes, and each transport pipe has a transport gas supply pipe equipped with a flow rate regulating valve. In a dispensing and conveying device configured to be connected so that the back pressure at the intake port is substantially constant,
A transportation valve that is fully open during transportation is provided in the vicinity of the pressurized tank of each of the transportation pipes, and a supply source valve is provided in the transportation gas supply pipe, and the supply of pressurized gas to the pressurized gas chamber is connected to the output of the indoor pressure detector. a pressure regulator that controls the flow rate of each transport gas to a constant value based on the pressure, and a transport gas flow rate controller that detects the pressure difference between the pressure near the transport pipe connection part of the supply pipe and the internal pressure of the pressurized gas chamber. It is configured to include a differential pressure regulator to be operated and a comparator to detect an abnormal output of the differential pressure regulator, and the transportation valve and the transportation gas supply source valve are fully closed by the output of the comparator. A powder distribution and transportation device characterized by: