System and method for absorbing alkali dust containing sodium carbonate powder

Abstract

The invention provides a sodium carbonate powder-containing alkali dust absorption system and method, the system comprises an absorption tower, the top of the absorption tower is provided with an inlet pressure monitoring meter, and the absorption tower is internally provided with a foam capturing wire mesh and a spraying liquid distribution pipe in sequence from top to bottom; a circulating pump, a dynamic wave feeding pipe, a fan and a sewage pump which are communicated with the absorption tower are respectively arranged at the side part of the absorption tower; alkali dust is introduced into an inlet of the dynamic wave feeding pipe, and a first-stage dynamic wave spray head and a second-stage dynamic wave spray head are sequentially arranged in the dynamic wave feeding pipe from top to bottom; the first-stage dynamic wave spray head is communicated with the circulating pump through a first-stage dynamic wave adjusting valve, and a first-stage dynamic wave pressure monitoring meter is arranged on a pipeline between the first-stage dynamic wave spray head and the circulating pump; and the second-stage dynamic wave spray head is communicated with the circulating pump through a second-stage dynamic wave adjusting valve. According to the invention, a synergistic purification process of two-stage dynamic wave absorption and one-stage spraying absorption is adopted, and efficient trapping and treatment are realized for alkali dust such as NaOH and KOH particles and aerosol generated by an alkali dissolving system.

Description

Technical Field

[0001] The invention belongs to the technical field of alkali dust absorption, and relates to an alkali dust absorption system and method containing sodium carbonate powder. Background Art

[0002] In the alkali dissolution process in fields such as hydrometallurgy, the crushing, dissolution, and storage of solid alkali (such as flake alkali and granular alkali) easily generate a large amount of alkali dust, mainly highly corrosive particles and aerosols such as NaOH and KOH. This alkali dust escapes into the production environment through open points such as the breathing port of the reactor and the material conveying interface, affecting operational safety, equipment life, and environmental protection. The specific defects are as follows: (1) Insufficient efficiency of traditional spray towers: Conventional spray towers rely on the inertial collision of droplets and dust to capture alkaline dust, but the capture efficiency of fine particles such as aerosol alkaline dust with a particle size of less than 5μm is insufficient, usually less than 80%. In addition, the uneven distribution of droplet size can easily lead to limited gas-liquid contact area. In a high-concentration alkaline dust environment, the pH value of the spray liquid rises rapidly, the consumption of neutralizers increases sharply, and the operating cost is high. (2) Poor applicability of physical filtration technology: Existing bag dust collectors are prone to filter material compaction and clogging in humid alkaline environments, requiring frequent replacement of filter bags, resulting in high maintenance costs. Although electrostatic precipitators have a certain effect on fine particles, high-humidity alkaline dust can easily cause discharge electrode corrosion and pose a high-voltage electrical safety hazard.

[0003] Based on the above background, there is an urgent need to develop an efficient treatment method for the alkali dust characteristics of the alkali dissolution system to achieve full process control from source escape to terminal emission, ensure that the workshop environment and exhaust concentration meet the standards, and reduce operating energy consumption and maintenance costs to adapt to continuous production needs. Summary of the Invention

[0004] The purpose of the present invention is to address the problems existing in the prior art and provide an alkali dust absorption system and method containing sodium carbonate powder, which solves the problem that the alkali dust absorption rate in the alkali dissolving system is insufficient, resulting in the alkali dust escaping into the production environment through open sites such as the breathing port of the reactor and the material conveying interface, thereby affecting operational safety, equipment life and environmental protection.

[0005] To this end, the present invention adopts the following technical solutions: An alkali dust absorption system containing sodium carbonate powder comprises an absorption tower provided with a liquid level gauge, a pH meter and an automatic water supply valve; an inlet pressure monitoring gauge is provided at the top of the absorption tower, a foam catching screen and a spray liquid distribution pipe are provided in sequence from top to bottom inside, and a plurality of spiral nozzles arranged in parallel are provided at the bottom of the spray liquid distribution pipe.

[0006] The side of the absorption tower is respectively provided with a circulation pump, a power wave feed pipe, a fan and a sewage pump connected thereto; the fan is provided with a fan inlet pressure monitoring gauge.

[0007] Alkali dust is introduced into the entrance of the power wave feed pipe, and the first-level power wave nozzle and the second-level power wave nozzle are arranged in sequence from top to bottom; among which: The first-stage power wave nozzle is connected to the circulation pump through the first-stage power wave regulating valve, and a first-stage power wave pressure monitoring meter is provided on the pipeline between the two; The secondary power wave nozzle is connected to the circulation pump through the secondary power wave regulating valve, and a secondary power wave pressure monitoring meter is provided on the pipeline between the two.

[0008] The circulation pump and the absorption tower are connected through a spray regulating valve, and the pipeline connecting the two is equipped with a spray pressure monitoring gauge.

[0009] A sewage pump is installed on the side of the absorption tower, which is interlocked with the liquid level meter and pH meter respectively; the liquid level meter is interlocked with the automatic water supply valve; and the inlet pressure monitoring meter is interlocked with the fan.

[0010] A method for absorbing alkali dust containing sodium carbonate powder, using the above-mentioned alkali dust absorption system, the method comprising the following steps: Alkali dust enters the absorption tower from top to bottom through the dynamic wave feed pipe; The circulation pump transports the liquid in the absorption tower to the power feed pipe; The liquid in the absorption tower is discharged by the first-stage dynamic wave nozzle and the second-stage dynamic wave nozzle. The liquid flows from bottom to top, forming a gas-liquid two-phase area. In this area, the liquid and gas collide with each other, the gas is wrapped by the liquid, the alkali dust dissolves in the absorption liquid, and the gas enters the absorption tower; The absorption liquid is sprayed inside the absorption tower through a spiral nozzle to atomize the absorption liquid to further absorb the alkali dust.

[0011] The beneficial effects of the present invention are: The present invention uses a multi-stage coordinated purification process of "two-stage dynamic wave absorption + one-stage spray absorption" to achieve efficient capture and deep treatment of alkali dust such as NaOH, KOH particles and aerosols generated by the alkali dissolution system. At the same time, combined with the circulation management of the absorption liquid, it achieves a good absorption effect in alkali dust treatment. Specifically: 1. This invention adopts a two-stage dynamic wave absorption device and uses a turbulent liquid curtain to intercept alkaline dust particles and gaseous alkaline substances of different particle sizes in a graded manner, thereby improving the capture efficiency of fine particles and aerosols. Combined with the deep purification of the spray tower, it improves the overall dust removal efficiency of the system. 2. In the present invention, the absorption liquid is precisely neutralized through closed-loop pH control, and the waste liquid can be transported to subsequent processes to recover alkaline substances, greatly reducing the burden of wastewater discharge and hazardous waste treatment. The closed negative pressure operation of the system suppresses the escape of alkaline dust from the source, significantly improving the air quality in the workshop. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1Schematic diagram of the structure of the system of the present invention.

[0013] In the figure, 1-circulation pump, 2-liquid level gauge, 3-pH meter, 4-secondary power wave nozzle, 5-secondary power wave regulating valve, 6-secondary power wave pressure monitoring gauge, 7-first-level power wave nozzle, 8-first-level power wave regulating valve, 9-first-level power wave pressure monitoring gauge, 10-spray regulating valve, 11-spray pressure monitoring gauge, 12-power wave feed pipe, 13-alkali dust, 14-inlet pressure monitoring gauge, 15-foam catching screen, 16-spray liquid distribution pipe, 17-spiral nozzle, 18-fan inlet pressure monitoring gauge, 19-fan, 20-sewage pump, 21-automatic water supply valve, 22-absorption tower. DETAILED DESCRIPTION

[0014] The technical solution of the present invention is described below in conjunction with the accompanying drawings and implementation methods.

[0015] like Figure 1 As shown, an alkali dust absorption system containing sodium carbonate powder includes: an absorption tower 22, with an inlet pressure monitoring gauge 14 provided at the top of the absorption tower 22, and a foam-catching screen 15 and a spray liquid distribution pipe 16 provided inside the absorption tower 22 from top to bottom. The spray liquid distribution pipe 16 has a plurality of spiral nozzles 17 arranged in parallel at the bottom. The inlet pressure monitoring gauge 14 is used to determine whether the pressure inside the tank in the factory is negative. The foam-catching screen 15 is used to eliminate gas-carried foam, further reduce the moisture carried by the alkali dust, and reduce the amount of absorption liquid discharged from the tower body.

[0016] The sides of the absorption tower 22 are respectively provided with a circulation pump 1, a power wave feed pipe 12, a fan 19 and a sewage pump 20 connected thereto; alkali dust 13 is introduced into the inlet of the power wave feed pipe 12, and a first-level power wave nozzle 7 and a second-level power wave nozzle 4 are sequentially arranged inside from top to bottom; among them: the first-level power wave nozzle 7 is connected to the circulation pump 1 through a first-level power wave regulating valve 8, and a first-level power wave pressure monitor 9 is provided on the pipeline between the two; the second-level power wave nozzle 4 is connected to the circulation pump 1 through a second-level power wave regulating valve 5, and a second-level power wave pressure monitor 6 is provided on the pipeline between the two.

[0017] Specifically, the outlet of circulating pump 1 is divided into three lines: Line I: The circulation pump delivers the absorption liquid in the tower body to the first-level power wave nozzle 7. The first-level power wave pressure monitor 9 reflects the first-level power wave flow rate. The flow rate is adjusted by the first-level power wave regulating valve 8. The first-level power wave regulating valve 8 adjusts the flow rate at the power wave by the valve opening; Line II: The circulating pump 1 delivers the absorption liquid in the tower body to the secondary power wave nozzle 4. The secondary power wave pressure monitor 6 reflects the secondary power wave flow rate. The flow rate is adjusted by the secondary power wave regulating valve 5. The secondary power wave regulating valve 5 adjusts the flow rate at the power wave by the valve opening. Line III: The circulating pump 1 delivers the liquid to the tower body spray distribution pipe 16, and the absorption liquid is evenly atomized through the spiral nozzle 17 to further absorb the alkali dust 13. The spray pressure monitoring meter 11 reflects the spray flow rate, and the flow rate is adjusted by the spray regulating valve 10.

[0018] The absorption tower 22 is provided with a liquid level meter 2, a pH meter 3 and an automatic water supply valve 21; the circulation pump 1 is connected to the absorption tower 22 through a spray regulating valve 10, and the pipeline connecting the two is provided with a spray pressure monitoring meter 11.

[0019] A sewage pump 20 is provided on the side of the absorption tower 22, which is interlocked with the liquid level meter 2 and the pH meter 3 respectively. When the liquid level of the tower body is higher than the set liquid level, the sewage pump 20 starts to transport the liquid in the tower to the next process. When the pH value is higher than the set value, the sewage pump 20 starts to transport the liquid in the tower to the next process.

[0020] The fan 19 is provided with a fan inlet pressure monitor 18; the inlet pressure monitor 14 is interlocked with the fan 19 so that the negative pressure in the production system is maintained at a set value. When the negative pressure is lower than the set value, the frequency slowly decreases, and when the negative pressure is higher than the set value, the frequency gradually increases.

[0021] The liquid level meter 2 is interlocked with the automatic water supply valve 21. When the tower liquid level is lower than the lower limit setting value, the automatic water supply valve 21 opens. When the liquid level is higher than the setting value, the automatic water supply valve 21 closes.

[0022] A method for absorbing alkali dust containing sodium carbonate powder, using the above-mentioned alkali dust absorption system, the method comprises the following steps: Alkali dust 13 enters absorption tower 22 from top to bottom through power wave feed pipe 12; The circulation pump 1 delivers the liquid in the absorption tower 22 to the power feed pipe 12; The liquid in the absorption tower 22 is discharged by the first-level dynamic wave nozzle 7 and the second-level dynamic wave nozzle 4. The liquid flows from bottom to top, forming a gas-liquid two-phase region. In this region, the liquid and gas collide with each other, the gas is wrapped by the liquid, and the alkali dust 13 is dissolved in the absorption liquid and the gas enters the absorption tower 22. The absorption liquid is sprayed inside the absorption tower 22 through the spiral nozzle 17 to atomize the absorption liquid, thereby further absorbing the alkali dust 13.

Claims

1. An alkali dust absorption system containing sodium carbonate powder, characterized in that: The absorption tower (22) comprises an inlet pressure monitor (14) at the top of the absorption tower (22), and a foam catching screen (15) and a liquid spraying pipe (16) are sequentially arranged inside the absorption tower (22) from top to bottom; The absorption tower (22) is provided with a circulation pump (1), a power wave feed pipe (12), a fan (19) and a sewage pump (20) in communication with the absorption tower (22). The alkali dust (13) is introduced into the inlet of the power wave feed pipe (12), and a first-stage power wave nozzle (7) and a second-stage power wave nozzle (4) are sequentially arranged inside from top to bottom; The first-stage power wave nozzle (7) is connected to the circulation pump (1) via a first-stage power wave regulating valve (8), and a first-stage power wave pressure monitor (9) is provided on the pipeline between the two. The secondary power wave nozzle (4) is connected to the circulation pump (1) via a secondary power wave regulating valve (5), and a secondary power wave pressure monitor (6) is provided on the pipeline between the two.

2. The alkali dust absorption system containing sodium carbonate powder according to claim 1, characterized in that: The absorption tower (22) is provided with a liquid level meter (2), a pH meter (3) and an automatic water replenishment valve (21).

3. The alkali dust absorption system containing sodium carbonate powder according to claim 1, characterized in that: The circulation pump (1) is connected to the absorption tower (22) via a spray regulating valve (10), and a spray pressure monitoring gauge (11) is provided in the pipeline connecting the two.

4. The alkali dust absorption system containing sodium carbonate powder according to claim 2, characterized in that: A sewage pump (20) is provided on the side of the absorption tower (22), and is interlocked with the liquid level meter (2) and the pH meter (3).

5. The alkali dust absorption system containing sodium carbonate powder according to claim 1, characterized in that: A plurality of spiral spray nozzles (17) arranged in parallel are provided at the bottom of the spray liquid distribution pipe (16).

6. The alkali dust absorption system containing sodium carbonate powder according to claim 1, characterized in that: The fan (19) is provided with a fan inlet pressure monitoring gauge (18).

7. The alkali dust absorption system containing sodium carbonate powder according to claim 2, characterized in that: The liquid level meter (2) is interlocked with the automatic water supply valve (21).

8. The alkali dust absorption system containing sodium carbonate powder according to claim 1, characterized in that: The inlet pressure monitor (14) is interlocked with the fan (19).

9. A method for absorbing alkali dust containing sodium carbonate powder, characterized in that: Using the alkali dust absorption system according to any one of claims 1 to 8, the method comprises the following steps: The alkali dust (13) enters the absorption tower (22) from top to bottom through the power wave feed pipe (12); The circulation pump 1 delivers the liquid in the absorption tower 22 to the power feed pipe (12); The liquid in the absorption tower (22) is discharged by the first-stage dynamic wave nozzle (7) and the second-stage dynamic wave nozzle (4), and the liquid flows from bottom to top, forming a gas-liquid two-phase region. In this region, the liquid and gas collide with each other, the gas is wrapped by the liquid, and the alkali dust (13) is dissolved in the absorption liquid and the gas enters the absorption tower (22); The absorption liquid is sprayed inside the absorption tower (22) through the spiral nozzle (17) to atomize the absorption liquid, thereby further absorbing the alkali dust (13).

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