CN114560302A

CN114560302A - Novel weighing and metering dry powder conveying device

Info

Publication number: CN114560302A
Application number: CN202210234581.XA
Authority: CN
Inventors: 陈明华; 王爱武; 喻宏伟; 余维豪; 秦艳梅; 傅嘉宾
Original assignee: Ningbo Yibu Technology Co ltd
Current assignee: Ningbo Yibu Technology Co ltd
Priority date: 2022-03-11
Filing date: 2022-03-11
Publication date: 2022-05-31

Abstract

The invention discloses a novel weighing and metering dry powder conveying device which comprises a large storage bin, a rotary feeder, a buffer bin, a double-shaft screw conveyor and a conveying tank, wherein the whole device comprises a blanking process, a loading process, a conveying process and a purging process; wherein, the conveying period T of the conveying tank comprises: the material feeding time T1, the conveying time T2, the purging time T3 and the waiting time T4, a DCS or PLC control system calculates the material consumption according to the smoke gas amount and the pollutant concentration, calculates the conveying times per hour, and adjusts the conveying frequency by adjusting the waiting time T4, so that instantaneous adjustment can be realized; the real-time adjustment of the dry powder conveying capacity is realized by matching with a DCS/PLC control system program, and the operation cost is saved. The whole equipment is simple, the equipment cost is low, the overhaul workload is small, the power consumption is low, the noise is low, the conveying capacity range is large, the accurate adjustment can be carried out according to the change of the smoke gas volume and the pollutant concentration, and the reaction is rapid.

Description

Novel weighing and metering dry powder conveying device

Technical Field

The invention relates to the technical field of dry powder conveying, in particular to a novel weighing and metering dry powder conveying device.

Background

The main components of the flue gas generated in the incinerator stage of the garbage incineration are dust, hydrogen chloride, sulfur dioxide, carbon dioxide, nitrogen oxide and the like, and a small amount of hydrogen fluoride, dioxin, furan and the like can be generated. The flue gas passes through a waste heat boiler, and enters a flue gas purification system after heat energy is utilized. At present, nitrogen oxides (NOx) are removed by denitration equipment, acid gases (SOx and HCl) are mainly removed by alkaline substances such as slaked lime, baking soda and the like, and dioxin and heavy metals are removed by adsorption of a filter cake layer formed on the surface of a filter bag by sprayed activated carbon powder. The particle size of the slaked lime and the activated carbon powder is generally 200 meshes.

The existing dry powder conveying device mainly discharges materials to the ejector through the rotary feeder at the bottom of the hopper of the storage bin, and sweeps and conveys the materials through the positive pressure of the Roots blower. One rotary feeder and one fan in the conveying mode can only supply one flue gas purification system, and the hopper of one storage bin can only be provided with one set of conveying device, is not provided with metering equipment and cannot meter and regulate flow on line. When a plurality of flue gas purification systems need dry powder supply, the hopper space at the bottom of the storage bin is limited, so that the number of the storage bins can be increased, and corresponding conveying equipment, instruments, civil engineering foundations and the like need to be added, thereby greatly increasing the engineering cost. Meanwhile, due to the fact that the conveying is carried continuously for a long time, the problem that the conveying pipeline is blocked can occur. In addition, when a bag-type dust collector is arranged in the flue gas purification system, the reactant can be retained in the bag filter cake layer for continuous reaction, so that the requirement can be met without continuous conveying.

To sum up, for the characteristics of the existing feeding system, the technical disadvantages are summarized as follows:

1. two Roots blowers are required to be matched for one set of conveying system, one Roots blower is used, and the other Roots blower is used, so that the equipment cost is high;

2. the Roots blower has high noise which is 95-105dB higher than 85dB of the national standard, and a noise reduction room is needed.

3. The Roots blower is complex in equipment, is provided with a blower, a motor, a silencer, a pressure gauge, a pressure release valve, a one-way valve and the like, and is large in overhauling and maintaining workload.

4. The length of the silencer is about 1.6m, the length of the Roots blower, the silencer and the ejector is about 6m, and the occupied area is too large.

5. There is no weighing and metering function.

6. The conveying capacity is adjusted by changing the frequency of the variable-frequency rotary feeder, the adjusting performance is poor, the error is large, the reaction is slow, and the material waste is caused by generally adopting quantitative conveying.

7. The Roots blower is always operated at full load, frequency conversion adjustment is not needed, and power consumption is high.

8. The existing feeding system mainly depends on the negative pressure generated by the ejector to suck materials into a pipeline from the rotary feeder and conveys the materials to a flue under the action of a positive pressure head of the Roots blower, the type selection of the ejector is very critical, the negative pressure disappears or weakens after the feeding system operates for a period of time, and the operation stability is poor.

9. The ejector is worn greatly and needs to be replaced regularly.

Therefore, it is urgently needed to develop a novel dry powder conveying device with weighing and metering functions, which is low in cost and stable in operation.

Disclosure of Invention

The invention aims to provide a novel weighing and metering dry powder conveying device with weighing and metering functions, which is low in cost and stable in operation, so as to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme:

a novel weighing and metering dry powder conveying device comprises a large storage bin, a rotary feeder, a buffer bin, a double-shaft screw conveyor and a conveying tank; the feeding hole of the large storage bin is butted with the discharging hole of the tank car for conveying the fine dry powder, the discharging hole of the large storage bin is connected with the rotary feeder through a pipeline, and a gate valve is arranged on a connecting pipeline between the rotary feeder and the large storage bin; the discharge port of the rotary feeder is in butt joint with the feed port A of the buffer bin through flexible connection, the discharge port A of the buffer bin is in butt joint with the feed port B of the double-shaft screw conveyor, and the discharge port B of the double-shaft screw conveyor is in butt joint with the feed port C of the conveying tank.

Furthermore, the buffer bin is provided with a feed inlet A, a cylinder body, an ear type support, a discharge outlet A, a high level meter mounting seat, a steel support, a weighing device and a pneumatic vibrator, and the size of the discharge outlet A is matched with that of the double-shaft screw conveyer; the number of the ear type supports is four, and the side ends of the four ear type supports are respectively connected with the cylinder body; the weighing device is arranged between the ear type support and the steel support, and the steel support is provided with two layers of steel beams; a material level switch A is arranged on a high material level meter mounting seat of the buffer bin and is linked with the rotary feeder, and when the rotary feeder is full of materials, the material level switch A alarms to stop the rotary feeder; the weight signal of the weighing device is calculated by a DCS/PLC control system to generate instantaneous flow and cumulant; the pneumatic vibrator is arranged below the side of the cylinder body, a vibrating electromagnetic valve is connected to the pneumatic vibrator, the vibrating electromagnetic valve is set to have pulse time of 2s and interruption time of 20s, and the pneumatic vibrator is started through compressed air.

Furthermore, the double-shaft screw conveyor is provided with a feed inlet B, a discharge outlet B, a motor, a conveying shaft, a tail bearing seat and an access hole; the double-shaft screw conveyor is a double-shaft double motor, each motor can run in two directions, the conveying shaft is a two-way conveying shaft, and the running direction of the motors is adjusted according to DCS/PLC control system signals; the access hole is used for overhauling and cleaning the internal material of the double-shaft screw conveyor, the double-shaft screw conveyor runs discontinuously, is opened when the conveying tank is fed, and stops after the conveying tank is full of materials.

Furthermore, the conveying tank adopts a straight cylinder type pressure container, a feed inlet C, a tank body, a discharge outlet C, an air inlet, a high material level meter port, a low material level meter port and a sewage outlet are arranged on the conveying tank, the material level meter is arranged at the high material level meter port when the dry powder conveying amount is large, and the material level meter is arranged at the low material level meter port when the dry powder conveying amount is small; wherein, a set of conveyor is furnished with four conveying tanks, can carry to one or more material points through four conveying tanks, when carrying to a material point, four conveying tanks can all use or can do three uses one and prepare for the use.

Furthermore, a pneumatic butterfly valve is arranged on a conveying pipeline of a feed inlet C on the conveying tank, and an air inlet electromagnetic valve is arranged on a connecting pipeline of an air inlet of the conveying tank; a material level switch B is also arranged on the high material level gauge port and the low material level gauge port on the conveying tank and used together with the installed material level gauge; an outlet pneumatic ball valve is mounted on a conveying pipeline of a discharge port C on the conveying tank and connected with a flue spray gun through a conveying pipeline, and a purging electromagnetic valve is mounted on a feeding conveying pipeline of the flue spray gun.

Furthermore, the conveying pipeline adopts a steel pipe or a rubber hose, the pipe diameter is DN25 when the conveying capacity of the dry powder is small, the pipe diameter is DN32/DN40 when the conveying capacity is large, the curvature radius of the elbow of the pipeline is 800mm, the flow velocity of the medium of the pipeline is 3-5m/s in the conveying process, and the conveying distance is 30-100 m.

Still further, the delivery cycle T of the delivery tank comprises: the feeding time T1, the conveying time T2, the purging time T3 and the waiting time T4, the DCS or PLC control system calculates the material consumption according to the smoke gas amount and the pollutant concentration, calculates the conveying times per hour, and adjusts the conveying frequency by adjusting the waiting time T4.

Compared with the prior art, the invention has the beneficial effects that:

1. the novel weighing and metering dry powder conveying device provided by the invention is simple in overall equipment, low in equipment cost and small in overhaul workload.

2. The novel weighing and metering dry powder conveying device provided by the invention has the advantages of less mechanical equipment, low power consumption and low noise.

3. The novel weighing and metering dry powder conveying device provided by the invention has the advantages of no ash leakage and good field environment.

4. The novel weighing and metering dry powder conveying device provided by the invention has a large conveying capacity range, can be accurately adjusted according to the change of the smoke gas quantity and the pollutant concentration, and is rapid in reaction.

5. The novel weighing and metering dry powder conveying device provided by the invention can be simultaneously provided with 4 conveying tanks and can correspond to one or more material using points.

6. According to the novel weighing and metering dry powder conveying device, the weighing module is arranged below the buffer bin, the weighing accuracy is high, only one bin hopper is needed, a conventional feeding system needs a plurality of bin hoppers or additional bins, and the bin construction cost is saved.

7. The novel weighing and metering dry powder conveying device provided by the invention is positioned below a large storage bin, occupies a floor of 1.5m multiplied by 2.5m, occupies a small area, does not occupy additional floor, and has a long conveying distance which can reach 100m at most.

Drawings

FIG. 1 is a process flow diagram of the conveyor apparatus of the present invention;

FIG. 2 is a front view of the conveyor of the present invention;

FIG. 3 is a side view of the structure of the conveyor of the present invention;

FIG. 4 is a diagram of a surge bin configuration of the present invention;

FIG. 5 is a front view of the twin screw conveyor of the present invention;

FIG. 6 is a top view of the twin screw conveyor of the present invention;

FIG. 7 is a structural view of a transfer pot of the present invention;

FIG. 8 is a process flow diagram of a transfer pot of the present invention;

FIG. 9 is a flow chart of the feed cycle of the present invention.

In the figure: 1. a large storage bin; 2. a gate valve; 3. a rotary feeder; 4. soft connection; 5. a buffer bin; 51. a feed inlet A; 52. a barrel; 53. an ear mount; 54. a discharge hole A; 55. a high level indicator mounting seat; 6. a material level switch A; 7. a weighing device; 8. vibrating an electromagnetic valve; 9. a pneumatic vibrator; 10. a twin screw conveyor; 111. a feed inlet B; 112. a discharge hole B; 113. a motor; 114. a delivery shaft; 115. a tail bearing seat; 116. an access hole; 11. supporting steel; 12. a pneumatic butterfly valve; 13. a delivery tank; 131. a feed inlet C; 132. a tank body; 133. a discharge port C; 134. an air inlet; 135. a high level gauge port; 136. a low level indicator port; 137. a sewage draining outlet; 14. an outlet pneumatic ball valve; 15. a flue spray gun; 16. an air inlet solenoid valve; 17. a material level switch B; 18. and purging the electromagnetic valve.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-3, the embodiment of the present invention provides a novel weighing and metering dry powder conveying device, which is used for conveying fine dry powder and is suitable for a dry desulfurization and deacidification system, and comprises a large storage bin 1, a rotary feeder 3, a buffer bin 5, a double-shaft screw conveyor 10 and a conveying tank 13; a feed port of the large storage bin 1 is butted with a discharge port of a tank car for conveying fine dry powder, the discharge port of the large storage bin 1 is connected with a rotary feeder 3 through a pipeline, and a gate valve 2 is arranged on a connecting pipeline between the rotary feeder 3 and the large storage bin 1; the discharge port of the rotary feeder 3 is in butt joint with the feed port A51 of the buffer bin 5 through the flexible joint 4, the discharge port A54 of the buffer bin 5 is in butt joint with the feed port B111 of the double-shaft screw conveyor 10, and the discharge port B112 of the double-shaft screw conveyor 10 is in butt joint with the feed port C131 of the conveying tank 13.

Referring to fig. 4, the volume of the surge bin 5 is about 500L, the surge bin 5 is provided with a feed port a51, a cylinder 52, an ear-type support 53, a discharge port a54, a high level gauge mounting seat 55, a steel support 11, a weighing device 7 and a pneumatic vibrator 9, and the size of the discharge port a54 is matched with that of the double-shaft screw conveyor 10; four ear supports 53 are provided, and the side ends of the four ear supports are respectively connected with the cylinder 52; the weighing device 7 is arranged between the ear type support 53 and the steel support 11, and the steel support 11 is provided with two layers of steel beams; a material level switch A6 is mounted on a high material level meter mounting seat 55 of the buffer bin 5, the material level switch A6 is interlocked with the rotary feeder 3, and when the rotary feeder 3 is fully filled, the material level switch A6 gives an alarm to stop the rotary feeder 3; the weight signal of the weighing device 7 is calculated by a DCS/PLC control system to generate instantaneous flow and cumulant, and the weighing precision is high; the pneumatic vibrator 9 is arranged below the side of the barrel 52, the pneumatic vibrator 9 is connected with a vibrating electromagnetic valve 8, the vibrating electromagnetic valve 8 is set to have pulse time of 2s and interruption time of 20s, and the pneumatic vibrator 9 is started through compressed air to prevent dry powder in the buffer bin 5 from bridging and causing unsmooth blanking.

Referring to fig. 5-6, the double-shaft screw conveyor 10 is provided with a feed port B111, a discharge port B112, a motor 113, a conveying shaft 114, a tail bearing seat 115 and a service port 116; the double-shaft screw conveyor 10 is a double-shaft double motor, each motor 113 can run in two directions, the conveying shaft 114 is a two-way conveying shaft, and the running direction of the motor 113 is adjusted according to a DCS/PLC control system signal; the access hole 116 is used for overhauling and cleaning the internal material evacuation of the double-shaft screw conveyor 10, the double-shaft screw conveyor 10 runs discontinuously, is opened when the conveying tank 13 feeds, and stops after the conveying tank 13 is full of materials.

Referring to fig. 7, the conveying tank 13 is a straight cylinder type pressure vessel, a feed inlet C131, a tank body 132, a discharge outlet C133, an air inlet 134, a high level gauge 135, a low level gauge 136 and a sewage outlet 137 are arranged on the conveying tank 13, the level gauge is installed at the high level gauge 135 when the dry powder conveying amount is large, and the level gauge is installed at the low level gauge 136 when the conveying amount is small; wherein, a set of conveyor is furnished with four delivery tanks 13, can convey to one or more material points through four delivery tanks 13, when conveying to a material point, four delivery tanks 13 can all use or can do three uses one and prepare for the use.

Referring to fig. 8, a pneumatic butterfly valve 12 is installed on a conveying pipeline of a feed port C131 of the conveying tank 13, and an intake solenoid valve 16 is installed on a connecting pipeline of an intake port 134 of the conveying tank 13; a material level switch B17 is also arranged on the high material level gauge port 135 and the low material level gauge port 136 on the conveying tank 13 and used together with the installed material level gauges; an outlet pneumatic ball valve 14 is mounted on a conveying pipeline of a discharge port C133 on the conveying tank 13, the outlet pneumatic ball valve 14 is connected with a flue spray gun 15 through the conveying pipeline, and a purging electromagnetic valve 18 is mounted on a feeding conveying pipeline of the flue spray gun 15.

The conveying pipeline in the embodiment of the invention adopts a steel pipe or a rubber hose, the pipe diameter is DN25 when the conveying capacity of the dry powder is small, the pipe diameter is DN32/DN40 when the conveying capacity is large, the curvature radius of the elbow of the pipeline is 800mm, the flow speed of the medium of the pipeline is 3-5m/s in the conveying process, the conveying distance is generally 30-50m, and the maximum distance can reach 100 m.

Referring to fig. 9, the delivery cycle T of the delivery tank 13 according to the embodiment of the present invention includes: the material feeding time T1, the conveying time T2, the purging time T3 and the waiting time T4 are adopted, a DCS or PLC control system calculates the material consumption according to the smoke gas amount and the pollutant concentration, the conveying frequency per hour is calculated, and the conveying frequency is adjusted by adjusting the waiting time T4, so that instantaneous adjustment can be realized; the real-time adjustment of the dry powder conveying amount is realized by matching with a DCS/PLC control system program, and the operation cost is saved.

Specifically, the feeding time T1 (blanking process): the fine dry powder is conveyed into a large material bin 1 through a tank car, when the conveying device runs, a gate valve 2, a rotary feeder 3 and a double-shaft screw conveyor 10 are opened, the dry powder falls into a buffer bin 5, and after the buffer bin 5 is full of materials, a material level switch A6 gives an alarm to close the rotary feeder 3 to stop discharging, and the loading process is started;

delivery time T2: during loading, the pneumatic butterfly valve 12 is opened, the double-shaft screw conveyor 10 is controlled to discharge materials to the corresponding conveying tank 13, the material level switch B17 gives an alarm after the conveying tank 13 is full of materials, and then the double-shaft screw feeder 10 and the pneumatic butterfly valve 12 are closed to enter the conveying process; an air inlet electromagnetic valve 16 is opened, compressed air enters a conveying tank 13 to be pressurized to about 0.2MPa, an outlet pneumatic ball valve 14 is opened, dry powder is conveyed to a flue spray gun 15 through a rubber hose or a steel pipe and sprayed into a flue, four conveying tanks 13 are arranged below a double-shaft screw conveyor 10, the four conveying tanks 13 are sequentially discharged and conveyed in one conveying period, and a purging process is carried out after the conveying process is finished.

Purge time T3: after the conveying of each conveying tank 13 is finished, in order to prevent the pipeline from being blocked by dry powder, the air inlet electromagnetic valve 16 and the outlet pneumatic ball valve 14 are closed, the purging electromagnetic valve 18 is opened, purging is closed after a period of time, the purging time is adjusted through the length of the pipeline, after purging is finished, the system enters the waiting time T4, and after waiting time T4 is finished, the system enters the conveying of the next conveying tank 13.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical solutions and the inventive concepts of the present invention within the technical scope of the present invention.

Claims

1. A novel dry powder conveying device with weighing and metering functions is characterized by comprising a large storage bin (1), a rotary feeder (3), a buffer bin (5), a double-shaft screw conveyor (10) and a conveying tank (13); a feed inlet of the large storage bin (1) is butted with a discharge outlet of a tank car for conveying fine dry powder, the discharge outlet of the large storage bin (1) is connected with the rotary feeder (3) through a pipeline, and a gate valve (2) is arranged on a connecting pipeline between the rotary feeder (3) and the large storage bin (1); the discharge port of the rotary feeder (3) is in butt joint with a feed port A (51) of the buffer bin (5) through a flexible connection (4), a discharge port A (54) of the buffer bin (5) is in butt joint with a feed port B (111) of the double-shaft screw conveyor (10), and a discharge port B (112) of the double-shaft screw conveyor (10) is in butt joint with a feed port C (131) of the conveying tank (13).

2. A novel gravimetric metering dry powder delivery system as set forth in claim 1 wherein: the buffer bin (5) is provided with a feed port A (51), a cylinder body (52), an ear type support (53), a discharge port A (54), a high level gauge mounting seat (55), a steel support (11), a weighing device (7) and a pneumatic vibrator (9), and the size of the discharge port A (54) is matched with that of the double-shaft screw conveyor (10); four ear type supports (53) are arranged, and the side ends of the four ear type supports are respectively connected with the cylinder body (52); the weighing device (7) is arranged between the ear type support (53) and the steel support (11), and the steel support (11) is provided with two layers of steel beams; a material level switch A (6) is mounted on a high material level meter mounting seat (55) of the buffer bin (5), the material level switch A (6) is interlocked with the rotary feeder (3), and when the rotary feeder (3) is fully fed, the material level switch A (6) gives an alarm to stop the rotary feeder (3); the weight signal of the weighing device (7) is calculated by a DCS/PLC control system to generate instantaneous flow and cumulant; the pneumatic vibrator (9) is arranged below the side of the cylinder body (52), the pneumatic vibrator (9) is connected with a vibrating electromagnetic valve (8), the vibrating electromagnetic valve (8) is set to have pulse time of 2s and interruption time of 20s, and the pneumatic vibrator (9) is started through compressed air.

3. A novel gravimetric metering dry powder delivery system as set forth in claim 2 wherein: the double-shaft screw conveyor (10) is provided with a feed inlet B (111), a discharge outlet B (112), a motor (113), a conveying shaft (114), a tail bearing block (115) and an access hole (116); the double-shaft screw conveyor (10) is a double-shaft double motor, each motor (113) can operate in two directions, the conveying shaft (114) is a two-way conveying shaft, and the running direction of the motors (113) is adjusted according to DCS/PLC control system signals; the overhaul port (116) is used for overhauling and cleaning the internal material of the double-shaft screw conveyor (10) to be emptied, the double-shaft screw conveyor (10) runs discontinuously, is opened when the conveying tank (13) feeds materials, and is stopped after the conveying tank (13) is full of materials.

4. A novel gravimetric metering dry powder delivery system as set forth in claim 3 wherein: the conveying tank (13) adopts a straight-barrel type pressure container, the conveying tank (13) is provided with a feed inlet C (131), a tank body (132), a discharge outlet C (133), an air inlet (134), a high level indicator port (135), a low level indicator port (136) and a sewage outlet (137), the level indicator is arranged at the high level indicator port (135) when the dry powder conveying capacity is large, and the level indicator is arranged at the low level indicator port (136) when the conveying capacity is small; wherein, a set of conveyor is furnished with four conveying tank (13), can convey to one or more material points through four conveying tank (13), when conveying to a material point, four conveying tank (13) can all use or can do three uses one and prepare for the use.

5. The novel gravimetric metering dry powder delivery device of claim 4, wherein: a pneumatic butterfly valve (12) is installed on a conveying pipeline of a feeding hole C (131) on the conveying tank (13), and an air inlet electromagnetic valve (16) is installed on a connecting pipeline of an air inlet (134) of the conveying tank (13); a material level switch B (17) is also arranged on the high material level gauge port (135) and the low material level gauge port (136) on the conveying tank (13) and used together with the installed material level gauge; an outlet pneumatic ball valve (14) is installed on a conveying pipeline of a discharge port C (133) on the conveying tank (13), the outlet pneumatic ball valve (14) is connected with a flue spray gun (15) through the conveying pipeline, and a purging electromagnetic valve (18) is installed on a feeding conveying pipeline of the flue spray gun (15).

6. The novel dry powder weighing and metering device as claimed in claim 5, wherein the conveying pipeline is a steel pipe or a rubber hose, the pipe diameter is DN25 when the dry powder conveying amount is small, the pipe diameter is DN32/DN40 when the dry powder conveying amount is large, the curvature radius of a pipeline elbow is 800mm, the flow velocity of a pipeline medium is 3-5m/s during conveying, and the conveying distance is 30-100 m.

7. A new gravimetric dry powder delivery device according to claim 5, characterized in that said delivery cycle T of said delivery tank (13) comprises: the feeding time T1, the conveying time T2, the purging time T3 and the waiting time T4, the DCS or PLC control system calculates the material consumption according to the smoke gas amount and the pollutant concentration, calculates the conveying times per hour, and adjusts the conveying frequency by adjusting the waiting time T4.