TWI490437B - Pulverized coal injection system of blast furnace and method for clearing out pulverized coal injecting pipe thereof - Google Patents

Description

Blast furnace pulverized coal blowing system and clearing method thereof

The invention relates to a method for clearing a pipeline, and in particular to a method for clearing a blast furnace pulverized coal blowing system and a coal injection pipeline thereof.

In blast furnace production operations, coke is the main fuel and reducing agent. However, due to the high production and purchase cost of coke, in recent years, the injection of pulverized coal into the blast furnace has been developed as a substitute for fuel and reducing agent, thereby reducing the amount of coke used and reducing the cost of producing molten iron. Therefore, the Pulverized Coal Injection Rate (PCR) is an important indicator for modern blast furnace operation.

Please refer to FIG. 1 , which is a schematic diagram showing a partial device of a general blast furnace pulverized coal blowing system. A typical blast furnace pulverized coal blowing system 100 mainly includes a distributor 102, a plurality of coal injection lines 104, and a plurality of coal injection guns (not shown). The dispenser 102 is typically placed at the top of the blast furnace. One end of the coal injection line 104 is connected to the distributor 102, and the other end of the coal injection line 104 is connected to a coal injection gun to communicate the distributor 102 with the coal injection gun. The coal injection gun is placed at the blast furnace mouth.

The blast furnace pulverized coal blowing system 100 of the blast furnace first grinds the raw coal into After the pulverized coal, the conveying gas, such as air and nitrogen, is used to pressurize and transport the pulverized coal. These pulverized coals are then distributed into a plurality of coal injection lines 104 via a distributor 102 of the furnace roof. Subsequently, the coal injection gun at the blast furnace mouth blows the pulverized coal into the blast furnace as part of the fuel and reducing agent of the iron making process.

The number of coal shotguns configured for each blast furnace is not necessarily the same. Since the curvature and length of the coal injection line 104 of the top distributor 102 to each coal injection gun are different, the pressure loss of each coal injection line 104 is different, and the pressure and flow rate of each coal injection gun may be inconsistent. At present, in order to solve this problem, the general ironworks will add a venturi 106 to each of the coal injection lines 104 downstream of the top distributor 102, as shown in FIG. Since the diameter of the smallest pipe diameter of the venturi 106 is only 12 mm, the pressure loss of the inlet and outlet of the venturi 106 can be up to 1 bar, so that the original pressure loss difference of each coal injection line 104 can be relatively small. Can be neglected, in order to achieve the purpose of controlling the consistency of the pressure and flow of each coal gun.

However, the diameter of the smallest pipe diameter of the venturi 106 is only half of the pipe diameter of the coal injection line 104, and the diameter of the venturi 106 is reduced, which often causes large raw coal, or rubber, screws, screws, etc. The foreign matter is clogged at the flange 108 above the venturi 106 (ie, the pulverized coal inlet end), causing the single or partial coal injection gun to fail to properly spray coal. Therefore, it is necessary to clean and remove the blockage of the plugging portion 110 of the coal injection line 104.

Generally, when cleaning the plugging in the coal injection line 104, the flange surface of the flange 108 above the venturi 106 is first disassembled, and the upper and lower pipelines are staggered. Next, the pipeline is backwashed from the downstream blast furnace side by high pressure gas, and the plugging, pulverized coal and high pressure gas inside the coal injection line 104 are blown out. The Ministry discharges it into the atmosphere to achieve the purpose of clearing the pipeline.

In the cleaning process of the venturi 106, the coal injection valve 112 of the clogging coal injection line 104 on the blast furnace side, the coal injection valve 118 and the purge valve 116 at the top of the blast furnace top are normally closed. Next, the pressure relief valve 114 near the coal injection valve 112 is opened to relieve residual pressure in the blocked coal injection line 104. After the pressure relief of the coal injection line 104 is completed, the pressure relief valve 114 is externally connected to a high pressure gas source to pressurize the coal injection line 104 with high pressure gas. After the coal injection line 104 is pressurized, the pressure relief valve 114 is closed, and the coal injection valve 112 on the blast furnace side is opened, thereby allowing the residual pulverized coal in the blocked coal injection line 104 to be blown into the blast furnace as much as possible. After the pressure between the coal injection line 104 and the blast furnace is balanced, the coal injection valve 112 on the blast furnace side is closed. Then, the coal injection line 104 is pressurized by the high pressure gas connected to the pressure relief valve 114, and then the pressure relief valve 114 is closed to open the coal injection valve 112 to discharge the coal injection line. The steps of charging and relieving pressure of the coal injection line 104 may be repeated several times to reduce the amount of pulverized coal escaping when the venturi 106 is removed.

Next, after it is determined that the coal injection valve 112 on the blast furnace side is closed, the high pressure gas source connected to the pressure relief valve 114 is removed, and the pressure relief valve 114 is opened to discharge the coal injection line 104 to atmospheric pressure. Upon completion of the pressure relief of the coal injection line 104, the maintenance personnel can be notified to disassemble the flange face of the flange 108 at the upstream end of the venturi 106. When the flange face of the flange 108 is disassembled, the venturi 106 should be tapped first after the screw is loosened, so that the residual pressure inside the coal injection line 104 can be slowly leaked out. In addition, when hitting the venturi 106, the staff must stand in the upwind to avoid contact with harmful substances such as pulverized coal and high-pressure gas. Moreover, it must be confirmed that the residual pressure in the coal injection line 104 is completely discharged before continuing The loosened screws are removed so that the flange faces of the flanges 108 at the upstream end of the venturi 106 are staggered.

Next, the operator on the blast furnace side is notified to connect the high pressure gas source to the pressure relief valve 114 again to perform backwashing of the coal injection line 104 using the high pressure gas. At the time of backwashing, high pressure gas, pulverized coal and plugs remaining in the coal injection line 104 are ejected from the flange 108 upstream of the venturi 106. After the high-pressure gas escaping from the flange surface of the upstream flange 108 of the venturi 106 is turned clean, the operator on the blast furnace side is notified to remove the high-pressure gas source at the pressure relief valve 114, and the pressure relief valve 114 is removed. Turn on to relieve the pressure of the coal injection line 104. After the pressure relief of the coal injection line 104 is completed, the maintenance personnel are notified to perform the flange 108 screw returning operation.

Next, the blow valve 116, the coal injection valves 112 and 118 are opened, and the control room is notified to perform the blow drive of the coal injection line 104. At the same time, it is observed whether the flange 108 has a leak. If there is no leakage, the removal of the blockage of the coal injection line 104 has been completed, and the coal injection operation can be added.

However, in such a plug removal operation, in addition to the operation of the valve bodies such as the coal injection valves 112 and 118, the purge valve 116, and the pressure relief valve 114, the flange 108 is also required to be disassembled. However, the manpower of the operation is limited, and it is impossible to eliminate the blockage by itself. The maintenance unit needs to be dispatched to cooperate, so the maintenance cost of the blast furnace will be increased. In addition, during the back-washing process of the flange 108 and the reverse washing process of the coal injection line 104, high-pressure gas, pulverized coal and plugging materials are ejected and discharged into the surrounding environment, which may cause environmental pollution. Moreover, when high-pressure gas, pulverized coal, and plugging are ejected from the flange 108, if the worker does not pay attention, it may cause eye damage or harmful substances to be inhaled.

Therefore, one aspect of the present invention provides a method for clearing a blast furnace pulverized coal blowing system and a coal injection line thereof, wherein a three-way shut-off valve is installed in the upstream of each venturi pipe in the coal injection pipeline, and These three-way shut-off valves are all connected to an external filter. In this way, the high pressure gas backwashed from the coal injection pipeline can filter the plugged material through the filter, and then recover the high pressure gas containing the pulverized coal through another coal injection pipeline, thereby improving the utilization rate of the pulverized coal.

Another aspect of the present invention provides a method for clearing a blast furnace pulverized coal blowing system and a coal injection line thereof, which can smoothly clean the blockage at the venturi without disassembling the venturi. The unit can carry out the plugging of the coal injection pipeline by its own manpower, and recover the residual pulverized coal in the blocked pipeline to the original system. Therefore, not only can the inspection personnel be harmed, but also the environmental pollution caused by the demolition process, and the maintenance cost of the blast furnace can be reduced.

According to the above object of the present invention, a blast furnace pulverized coal blowing system is proposed. The blast furnace pulverized coal blowing system comprises a distributor, a plurality of coal injection lines, a plurality of venturi tubes, a plurality of three-way shut-off valves, and a filter. The coal injection pipelines are respectively connected to the distributor, and each of the coal injection pipelines is provided with a first coal injection valve, a second coal injection valve, a blow valve and a first pressure relief valve. The aforementioned venturi tubes are respectively disposed on the coal injection pipeline, wherein the first coal injection valve and the purge valve of each coal injection pipeline are located upstream of the venturi, and the second coal injection valve and the first pressure relief valve are located at the text. Downstream of the tube. The filter is connected to the coal injection line through a plurality of three-way shut-off valves. These three-way shut-off valves are respectively corresponding to The aforementioned coal injection line. The first three-way shut-off valve and the second three-way shut-off valve of the three-way shut-off valves are respectively disposed on one of the coal injection pipelines and one of the other normal pipelines.

According to an embodiment of the invention, the first three-way shut-off valve is disposed upstream of the venturi of the blocked line, and the second three-way shut-off valve is disposed upstream of the venturi of the other normal pipeline. .

According to another embodiment of the present invention, the blast furnace pulverized coal blowing system further includes a first recovery valve and a first filtration valve, and a second recovery valve and a second filtration valve. The first recovery valve and the first filter valve are disposed between the filter and the first three-way shut-off valve, and the second recovery valve and the second filter valve are disposed between the filter and the second three-way shut-off valve.

According to still another embodiment of the present invention, the filter includes a filter plate, a second pressure relief valve and a bleed valve.

According to still another embodiment of the present invention, the filter plate is provided with a plurality of filter holes, and the diameter of each filter hole is less than or equal to the minimum pipe diameter of the venturi.

According to the above object of the present invention, a clearing method of a coal injection line of a blast furnace pulverized coal blowing system is also proposed. Among them, the blast furnace pulverized coal blowing system comprises a plurality of coal injection pipelines. The cleaning method of the coal injection line of the blast furnace pulverized coal blowing system comprises the following steps. Providing a filter in the blast furnace pulverized coal blowing system, wherein the filter is respectively connected to the plurality of coal injection lines through a plurality of three-way shut-off valves, and the filter is turned off through one of the three-way shut-off valves The valve and a second three-way shut-off valve are in communication with one of the plugging lines and one of the other normal lines of the aforementioned coal injection line, respectively. a first recovery valve A first filter valve is disposed between the filter and the first three-way shut-off valve, and a second recovery valve and a second filter valve are disposed between the filter and the second three-way shut-off valve. A pressure relief treatment is performed on the blocked pipeline. Switch each of the blocked lines to the other normal line to a gas seal state. A backwashing process is performed on the blocked line by a high pressure gas to blow off at least one plug in the blocked line from a blockage. The first three-way shut-off valve, the second three-way shut-off valve, the first filter valve, and the second recovery valve are opened. Performing a filtration and recovery step to blow the at least one blockage and the residual pulverized coal in the plugged line into the filter through the first three-way shut-off valve and the first filter valve by using a high-pressure gas, and to make the high-pressure gas and the residual The pulverized coal enters the aforementioned normal line via the second recovery valve and the second three-way shut-off valve.

According to an embodiment of the present invention, before the switching of the other normal pipelines to the gas seal state, the clearing method of the coal injection pipeline of the blast furnace pulverized coal blowing system further comprises performing the other of the other normal pipelines. A blow drive step.

According to another embodiment of the present invention, the blast furnace pulverized coal blowing system further comprises a plurality of venturi pipes correspondingly disposed on the coal injection pipeline, and each of the coal injection pipelines is respectively located upstream of the venturi and One of the downstream first coal injection valve and one blow valve, and a second coal injection valve and a first pressure relief valve.

According to still another embodiment of the present invention, when the backwashing treatment is performed, the first coal injection valve, the purge valve and the second coal injection valve for closing the blocked pipeline are included; and the high pressure is applied to the blocked pipeline from the first pressure relief valve. gas.

According to still another embodiment of the present invention, the filter includes a filter plate, a second pressure relief valve and a bleed valve. Moreover, in the filtration and recovery steps After the step, the clearing method of the coal injection line of the blast furnace pulverized coal blowing system further comprises opening the second pressure relief valve for filter pressure relief; and opening the leakage valve and at least one plugging device from the filter Take out.

100‧‧‧Blast Furnace Pulverized Coal Blowing System

102‧‧‧Distributor

104‧‧‧Pulverizing pipeline

106‧‧‧ Venturi tube

108‧‧‧Flange

110‧‧‧Clogs

112‧‧‧Spoke valve

114‧‧‧Relief valve

116‧‧‧Blowing valve

118‧‧‧Pulverizing valve

200‧‧‧Blast Furnace Pulverized Coal Blowing System

202‧‧‧Distributor

204a‧‧‧Spoke line

204b‧‧‧Pulverizing pipeline

206‧‧‧ venturi tube

208‧‧‧ blocked

210a‧‧‧Three-way shut-off valve

210b‧‧‧Three-way shut-off valve

212‧‧‧Spoke valve

214‧‧‧pressure relief valve

216‧‧‧Blowing valve

218‧‧‧Spoke valve

220‧‧‧Recovery valve

222‧‧‧Filter valve

224‧‧‧Filter valve

226‧‧‧Recovery valve

228‧‧‧Filter plate

230‧‧‧pressure relief valve

232‧‧‧Drain valve

234‧‧‧Filter

236‧‧‧ Filter holes

238‧‧‧ Space

240‧‧‧ space

The above and other objects, features, advantages and embodiments of the present invention will become more apparent and understood.

Figure 1 is a schematic view showing a partial device of a general blast furnace pulverized coal blowing system.

2 is a schematic view showing a partial device of a blast furnace pulverized coal blowing system according to an embodiment of the present invention.

Please refer to FIG. 2, which is a partial schematic view of a blast furnace pulverized coal blowing system according to an embodiment of the present invention. In the present embodiment, the blast furnace pulverized coal blowing system 200 may mainly include a distributor 202, a plurality of coal injection lines, a plurality of venturi tubes 206, a plurality of three-way shut-off valves, and a filter 234. A blast furnace pulverized coal blowing system 200 can have a plurality of coal injection lines, and only two coal injection lines 204a and 204b are illustrated in Fig. 2 for illustration. In the embodiment illustrated in Figure 2, the coal injection line 204a is a blocked line having a blockage 208, and the coal injection line 204b is a normal line without a blockage.

In the blast furnace pulverized coal blowing system 200, the distributor 202 is typically disposed at the top of the blast furnace. All of the coal injection lines 204a and 204b are in communication with the distributor 202 at one end. The other end of the coal injection lines 204a and 204b is connected to a coal injection gun. Therefore, each of the coal injection lines 204a and 204b can have one The coal injection gun is in communication with the distributor 202. In general, the coal injection gun is placed at the blast furnace blower. The distributor 202 can distribute the pulverized coal formed by grinding the raw coal into all of the coal injection lines 204a and 204b. The coal injection lines 204a and 204b can utilize a delivery gas, such as air and nitrogen, to pressurize and deliver the pulverized coal, which is sent to a coal injection gun. Subsequently, these coal shotguns located at the blast furnace blast nozzle can blow the pulverized coal into the blast furnace as part of the fuel and reducing agent of the iron making process.

In the present embodiment, each of the coal injection lines 204a and 204b is provided with coal injection valves 218 and 212, a purge valve 216, and a pressure relief valve 214. The coal injection valves 218 and 212, the purge valve 216 and the pressure relief valve 214 may be manual valves or other forms of shut-off valves. The venturi tubes 206 are respectively disposed on the coal injection lines 204a and 204b, thereby improving the consistency of the pressure and flow rate of each of the coal injection guns. In some embodiments, on each of the coal injection lines 204a and 204b, the coal injection valve 218 and the purge valve 216 are located upstream of the venturi 206, while the coal injection valve 212 and the pressure relief valve 214 are located in the venturi 206. Downstream. That is, the coal injection valve 218 and the purge valve 216 are adjacent to the top of the blast furnace, and the coal injection valve 212 and the pressure relief valve 214 are adjacent to the blast furnace side coal injection gun.

The blast furnace pulverized coal blowing system 200 can have a plurality of three-way shut-off valves, wherein the three-way shut-off valves are respectively disposed on the coal injection line. Only the two-way three-way shutoff valves 210a and 210b are illustrated in Fig. 2 for illustration. In some embodiments, the three-way shut-off valve 210a represents a three-way shut-off valve disposed on the blocked coal injection line 204a, and the three-way shut-off valve 210b represents a three-way shut-off disposed on other normal coal injection lines 204b that are not blocked. valve. The filter 234 is engaged between the coal injection line 204a and the coal injection line 204b, and is passed through three The shut-off valve 210a communicates with the blocked coal injection line 204a and communicates with the normal coal injection line 204b through the three-way shut-off valve 210b. In other embodiments, the three-way shut-off valve 210a may be disposed on a line in which the filter 234 and the coal injection line 204a are engaged, and the three-way shut-off valve 210b may be disposed on a line in which the filter 234 and the coal injection line 204b are engaged. As shown in Fig. 2, the three-way shut-off valve 210a is disposed upstream of the venturi 206 of the plugged coal injection line 204a, and the three-way shut-off valve 210b is disposed upstream of the venturi 206 of the normal coal injection line 204b.

In some embodiments, the filter 234 can include a filter plate 228, a pressure relief valve 230, and a bleed valve 232. The filter plate 228 is disposed inside the filter 234, and divides the interior of the filter 234 into two spaces 238 and 240. The pressure relief valve 230 and the relief valve 232 are respectively located on opposite sides of the filter plate 228. A plurality of filter holes 236 are provided in the filter plate 228. In an exemplary embodiment, the aperture of each filter aperture 236 is preferably less than or equal to the diameter of the tube at the smallest diameter of the venturi 206. With such a design, plugs having a diameter greater than or equal to the inner diameter of the venturi 206 of the coal injection lines 204a and 204b can be filtered by the filter plate 228.

In addition, the blast furnace pulverized coal blowing system 200 may further include a plurality of recovery valves and a plurality of filtration valves. In the embodiment shown in Fig. 2, only two recovery valves 220 and 226 and two filter valves 222 and 224 are illustrated. The filter valves 222 and 224 are in communication with the filter plate 228 in a space 238 in the filter 234, and the recovery valves 220 and 226 are in communication with another space 240 in which the filter plate 228 is separated in the filter 234. Moreover, the recovery valve 220 and the filter valve 222 are interposed between the blocked coal injection line 204a and the three-way shut-off valve 210a. Between the filter 234 and the filter 234, the recovery valve 226 and the filter valve 224 are interposed between the three-way shut-off valve 210b and the filter 234 on the normal coal injection line 204b.

Referring to FIG. 2 again, in an embodiment, when clearing the coal injection line 204a, the blast furnace pulverized coal blowing system 200 provided with the filter 234 is provided first, that is, the general blast furnace pulverized coal blowing system is not A filter 234 is installed, and in the present embodiment, the filter 234 is installed first. As described above, in the blast furnace pulverized coal blowing system 200, the filter 234 is communicated with the blocked coal injection line 204a and the normal coal injection line 204b through the three-way shut-off valve.

In some embodiments, the plugged coal injection line 204a may be subjected to a pressure relief process. When the clogging coal injection line 204a is subjected to the pressure relief treatment, the blow valve 216 and the coal injection valves 218, 212 are first closed, and then the pressure relief valve 214 upstream of the coal injection gun is used for pressure relief to block the coal injection line 204a. The residual pressure inside is released. When the pressure relief valve 214 is used for pressure relief, it is possible to simultaneously test whether the coal injection valve 212 at the inlet of the coal injection gun has an internal leak.

After the pressure relief treatment of the plugging coal injection line 204a is completed, the clearing process of the plugged coal injection line 204a is performed. When clearing the blocked coal injection line 204a, the blocked coal injection line 204a and the normal coal injection line 204b may be first switched to the gas seal state. However, in some embodiments, before the normal coal injection line 204b is switched to the gas seal state, the blow-discharge process for the normal coal injection line 204b used as the recovery line may be performed first, and the blow-discharge process is performed as a normal spray. The coal line 204b stops the coal injection, and the coal injection line 204b is blown clean, and the coal injection line 204b is maintained in a gas-sealed state. Then, a high pressure gas source is externally connected to the pressure relief valve 214 that blocks the coal injection line 204a to guide the high pressure gas. Into the plugged coal injection line 204a, the high pressure gas is used to perform the backwashing treatment of the plugging coal injection line 204a, and one or more plugs plugged in the blocked coal injection line 204a are blown away from the plugging 208 thereof.

At the same time, filtration and recovery steps can be performed. In this filtration and recovery step, the three-way shut-off valve 210a that blocks the coal injection line 204a and the filter valve 222 of the filter 234 are first opened. The recovery valve 226 of the filter 234 is opened again with the three-way shut-off valve 210b of the normal coal injection line 204b. At this time, the high pressure gas may backwash the plugging off the plugging coal line 204a, and may block the plugged material and the residual pulverized coal that is blown away from the plugging coal line 204a by the high pressure gas through the three-way shut-off valve 210a and the filter valve 222. And blowing into the filter 234. The plug is filtered through filter plate 228 in space 238 of the lower layer. On the other hand, the residual pulverized coal brought by the high pressure gas together with the self-blocking coal injection line 204a can pass through the filter hole 236 of the filter plate 228, and then enters the recovery line through the recovery valve 226 and the three-way shut-off valve 210b. The coal injection line 204b is recovered into the blast furnace via the recovery coal injection line 204b.

When the filtration and recovery steps are performed, it is possible to confirm whether or not pulverized coal is ejected from the Peep Sight behind the blast pipe of the coal injection line 204b. When it is observed that the pulverized coal blow drive is completed and turned into a clean gas, it is confirmed that the clearing process of the plugged coal injection line 204a is completed.

Next, a recovery step can be performed. In this recovery step, the pressure relief valve 214 of the coal injection line 204a after clearing may be closed, and the high pressure gas source externally connected to the pressure relief valve 214 may be removed. Next, the three-way shut-off valve 210a of the coal injection line 204a and the three-way shut-off valve 210b of the coal injection line 204b, and the filter valve 222 and the recovery valve 226 of the filter 234 are closed. Subsequently, the coal injection is started. Coal injection valves 218 and 212 of line 204a, and purge valve 216. Then, the control room can be notified to add the coal injection line 204a of Qingtong and the coal injection line 204b as a recovery line to the rank of coal injection.

In addition, the emptying process of the filter 234 can be performed. In the emptying process of the filter 234, the pressure relief valve 230 above the filter 234 may be opened to vent the residual pressure in the filter 234. After the pressure relief of the filter 234 is completed, the bleed valve 232 under the filter 234 is opened, and the clogging filtered in the lower space 238 of the filter 234 is taken out from the filter 234.

It can be seen from the above embodiments that one of the advantages of the present invention is that the blast furnace pulverized coal blowing system of the present invention is equipped with a three-way shut-off valve at the upstream of each venturi in the coal injection pipeline, and that these three-way shut-off valves are Connect to an external filter. Therefore, the high-pressure gas backwashed from the coal injection pipeline can filter the plugged material through the filter, and then recover the high-pressure gas containing the pulverized coal through another coal injection pipeline, thereby improving the utilization rate of the pulverized coal.

According to the above embodiments, another advantage of the present invention is that the cleaning method of the coal injection pipeline of the blast furnace pulverized coal blowing system of the present invention can smoothly clean the venturi at the venturi without disassembling the venturi. Therefore, the operating unit can carry out the plugging operation of the coal injection pipeline by its own manpower, and recover the residual pulverized coal of the blocked pipeline into the original system. Therefore, not only can the inspection personnel be harmed, but also the environmental pollution caused by the demolition process, and the maintenance cost of the blast furnace can be reduced.

While the present invention has been described above by way of example, it is not intended to be construed as a limitation of the scope of the invention. because The scope of the present invention is defined by the scope of the appended claims.

200‧‧‧Blast Furnace Pulverized Coal Blowing System

202‧‧‧Distributor

204a‧‧‧Spoke line

204b‧‧‧Pulverizing pipeline

206‧‧‧ venturi tube

208‧‧‧ blocked

210a‧‧‧Three-way shut-off valve

210b‧‧‧Three-way shut-off valve

212‧‧‧Spoke valve

214‧‧‧pressure relief valve

216‧‧‧Blowing valve

218‧‧‧Spoke valve

220‧‧‧Recovery valve

222‧‧‧Filter valve

224‧‧‧Filter valve

226‧‧‧Recovery valve

228‧‧‧Filter plate

230‧‧‧pressure relief valve

232‧‧‧Drain valve

234‧‧‧Filter

236‧‧‧ Filter holes

238‧‧‧ Space

240‧‧‧ space

Claims (10)

A blast furnace pulverized coal blowing system comprises: a distributor; a plurality of coal injection pipelines, wherein the coal injection pipelines are respectively connected with the distributor, and each of the coal injection pipelines is provided with a first coal injection valve, a second coal injection valve, a blow valve and a first pressure relief valve; a plurality of venturi pipes respectively corresponding to the coal injection pipelines, wherein the first coal injection of each of the coal injection pipelines a valve and the blow valve are located upstream of the venturi, the second coal injection valve and the first pressure relief valve are located downstream of the venturi; a plurality of three-way shut-off valves are respectively disposed corresponding to the coal injection In the pipeline, one of the three-way shut-off valves and the second three-way shut-off valve are respectively disposed on one of the plugging pipelines and the other normal pipelines of the coal injection pipelines; A filter is communicated with the coal injection lines through the three-way shut-off valves. The blast furnace pulverized coal blowing system of claim 1, wherein the first three-way shut-off valve is disposed upstream of the venturi of the clogging line, and the second three-way shut-off valve is disposed at the other normal pipelines The person is upstream of the venturi. The blast furnace pulverized coal blowing system of claim 2, further comprising: a first recovery valve and a first filtration valve disposed between the filter and the first three-way shut-off valve; and a second recovery The valve and a second filter valve are disposed between the filter and the second three-way shut-off valve. The blast furnace pulverized coal blowing system of claim 1, wherein the filter comprises a filter plate, a second pressure relief valve and a bleed valve. The blast furnace pulverized coal blowing system of claim 4, wherein the filter plate is provided with a plurality of filter holes, and each of the filter holes has a pore diameter smaller than or equal to a minimum diameter of one of the venturi tubes. A clearing method for a coal injection pipeline of a blast furnace pulverized coal blowing system, wherein the blast furnace pulverized coal blowing system comprises a plurality of coal injection pipelines, and the clearing method of the coal injection pipeline of the blast furnace pulverized coal blowing system comprises: setting a filter in the blast furnace pulverized coal blowing system, wherein the filter is respectively connected to the coal injection pipelines through a plurality of three-way shut-off valves, and the filter passes through one of the three-way shut-off valves a shut-off valve and a second three-way shut-off valve are respectively connected to one of the plugging pipelines and one of the other normal pipelines, and a first recovery valve and a first filter valve are disposed on the filter Between the first three-way shut-off valve, a second recovery valve and a second filter valve are disposed between the filter and the second three-way shut-off valve; a pressure relief treatment is performed on the blocked pipeline; Disconnecting the blocked line from the one of the other normal lines into a gas-sealed state; performing a backwashing treatment on the blocked line by using a high-pressure gas to blow off at least one blockage in the blocked line from a blockage ; turn on the first three-way switch off The second three-way shut-off valve, the first valve and the second filter recovery valve; and performing filtration with a recovery step, using the high pressure gas to at least one of the a plug and a residual pulverized coal in the plugged line are blown into the filter through the first three-way shut-off valve and the first filter valve, and the high-pressure gas and the residual pulverized coal are passed through the second recovery valve The second three-way shut-off valve enters one of the other normal lines. The clearing method of the coal injection pipeline of the blast furnace pulverized coal blowing system according to claim 6, wherein before the one of the normal pipelines is switched to the gas sealing state, the coal injection pipeline of the blast furnace pulverized coal blowing system The clearing method further includes a blow-off step for the other of the other normal pipelines. The cleaning method of the coal injection pipeline of the blast furnace pulverized coal blowing system according to claim 6, wherein the blast furnace pulverized coal blowing system further comprises a plurality of venturi pipes respectively corresponding to the coal injection pipelines, and each One of the coal injection lines is provided with a first coal injection valve and a blow valve, and a second coal injection valve and a first pressure relief valve respectively located upstream and downstream of the venturi. The cleaning method of the coal injection pipeline of the blast furnace pulverized coal blowing system according to claim 8, wherein the backwashing treatment comprises: closing the first coal injection valve of the blocked pipeline, the blow valve and the a second coal injection valve; and applying the high pressure gas to the blocked line from the first pressure relief valve. The method for clearing a coal injection line of a blast furnace pulverized coal blowing system according to claim 6, wherein the filter comprises a filter plate, a second pressure relief valve and a venting valve, and the filtering and recycling step After that, the clearing method of the coal injection pipeline of the blast furnace pulverized coal blowing system further comprises: Opening the second pressure relief valve to perform the filter pressure relief; and opening the pressure relief valve and removing the at least one blockage from the filter.