Pickling treatment system and use method therefor

Abstract

The present invention relates to a pickling treatment system, comprising at least three pickling treatment units arranged in series. Each pickling treatment unit is equipped with a circulating acid tank, the circulating acid tanks being connected in series by means of cascade flow pipes, the last circulating acid tank being provided with a fresh acid pipe; at least some of the remaining circulating acid tanks are offline acid tanks, the offline acid tanks being equipped with overrun pipes, two ends of an overrun pipe being connected to cascade flow pipe sections on an inlet side and an outlet side of the offline acid tank, respectively, and control valves being provided on the overrun pipes and the cascade flow pipe sections on the inlet side and the outlet side, respectively. In addition, the present invention relates to a use method for the pickling treatment system. In the present invention, the circulating acid tanks are connected in series and a number of offline acid tanks are provided, allowing for flexible control of the number and combination of the pickling treatment units put into a pickling process, so as to meet the pickling requirements of different production conditions without setting up multiple production lines or stopping production to re-prepare a pickling solution, thereby significantly reducing equipment investment and production costs.

Description

Pickling treatment system and method of use thereof Technical Field

[0001] The invention belongs to the technical field of metallurgical production, and in particular relates to a pickling treatment system and a method for using the pickling treatment system. Background Art

[0002] In the process of pickling non-oriented high-grade silicon steel plates and strips using hydrochloric acid as the pickling liquid, since there are many grades of non-oriented high-grade silicon steel products, and the silicon steel raw materials of different product grades have different requirements for pickling time and pickling liquid concentration, this requires the use of different production lines, thereby greatly increasing the equipment investment cost and floor space, or when switching steel grades, it is necessary to shut down the machine to re-prepare the pickling liquid, resulting in high production costs and low production efficiency.

[0003] Summary of the Invention

[0004] The present invention relates to a pickling treatment system and a method for using the pickling treatment system, which can at least solve some of the defects of the prior art.

[0005] The present invention relates to a pickling treatment system, comprising at least three pickling treatment units arranged in series, each of which is provided with a circulating acid tank, each of which is connected in series via a ladder flow pipe, wherein:

[0006] The circulating acid tank of the first-stage pickling treatment unit is equipped with an acid discharge pipe.

[0007] The circulating acid tank of the final pickling treatment unit is equipped with a new acid pipe.

[0008] At least some of the remaining circulating acid tanks are offline acid tanks, which are equipped with an override pipe and an offline control valve group. The two ends of the override pipe are respectively connected to the ladder flow pipe sections on the inlet and outlet sides of the offline acid tank. The offline control valve group includes a first control valve arranged on the override pipe and two second control valves respectively arranged on the ladder flow pipe sections on the inlet and outlet sides. The second control valve is located between the offline acid tank and the corresponding side override pipe bypass connection point.

[0009] The circulating acid tank is connected to the corresponding pickling treatment unit through an acid supply pipe and a reflux pipe, and a heater is provided on the acid supply pipe.

[0010] The circulating acid tank is also provided with a bypass pipe, which is connected to the acid supply pipe section on the outlet side of the heater.

[0011] A cleaning unit and a strip surface drying unit are connected in series downstream of the final pickling treatment unit.

[0012] The cleaning unit adopts a multi-stage countercurrent cascade cleaning unit.

[0013] The present invention has at least the following beneficial effects:

[0014] In the present invention, the circulating acid tanks are connected in series in a cascade flow and a number of offline acid tanks are provided, which can flexibly control the number and combination of pickling treatment units put into pickling work, thereby meeting the pickling requirements of different production conditions. For example, it can meet the different requirements of pickling time / acid concentration for the production of different high-grade silicon steels. There is no need to set up multiple production lines or shut down for re-preparing the pickling solution, which can significantly reduce equipment investment and production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] FIG1 is a schematic structural diagram of a pickling treatment system provided in an embodiment of the present invention;

[0017] FIG2 is a schematic structural diagram of an inductively controlled hydrogen pickling tank provided in an embodiment of the present invention;

[0018] FIG3 is a schematic diagram of the structure of the inducer provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0020] Example 1

[0021] As shown in FIG1 , an embodiment of the present invention provides a pickling treatment system, comprising at least three pickling treatment units 1 arranged in series, each of the pickling treatment units 1 being respectively equipped with a circulating acid tank 2, each of the circulating acid tanks 2 being connected in series via a ladder flow pipe 42, wherein:

[0022] The circulating acid tank 2 of the first-stage pickling treatment unit 1 is provided with an acid liquid discharge pipe 43.

[0023] The circulating acid tank 2 of the final pickling treatment unit 1 is provided with a new acid pipe 41.

[0024] At least part of the remaining circulating acid tanks 2 are offline acid tanks, which are equipped with an override pipe 21 and an offline control valve group. The two ends of the override pipe 21 are respectively connected to the ladder pipe 42 sections on the inlet and outlet sides of the offline acid tank. The offline control valve group includes a first control valve 211 provided on the override pipe 21 and two second control valves 22 respectively provided on the ladder pipe 42 sections on the inlet and outlet sides. The second control valve 22 is located between the offline acid tank and the corresponding side override pipe 21 bypass connection point.

[0025] The pickling treatment unit 1 can adopt a trough-type structure, that is, it can be configured as a pickling tank. In one embodiment, the pickling tank includes a tank body and a tank cover. The tank body is preferably a narrow steel structure. The tank cover preferably includes multiple top cover segments, each of which is arranged in sequence along the length of the tank body. The top cover segments can be automatically opened and closed by an opening and closing drive device, which includes but is not limited to a hydraulic drive. In one embodiment, the inner surface of the tank body is lined with corrosion-resistant vulcanized rubber as a first layer, and the second layer is lined with acid-resistant stone. The first layer is attached to the outer surface of the second layer. Preferably, the bottom of the tank body is V-shaped, and an emptying port can be provided at the lowest point. Wear-resistant strips of stone are preferably provided at regular intervals on the V-shaped slope to support the strip. Preferably, a side spray unit is provided on the tank body wall to spray acid into the tank.

[0026] The circulating acid tank 2 and the pickling treatment unit 1 are connected via an acid supply pipe 31 and a return pipe 32. Furthermore, a bypass pipe 36 may be connected to the acid supply pipe 31, which is connected to the circulating acid tank 2. Both the bypass pipe 36 and the acid supply pipe 31 are equipped with control valves, with the control valve on the acid supply pipe 31 preferably located downstream of the bypass connection point of the bypass pipe 36. Furthermore, a drain pipe 33 provided on the pickling treatment unit 1 may also be connected to the circulating acid tank 2, and this drain pipe 33 is equipped with a drain valve.

[0027] As shown in FIG1 , a heater 34 is preferably provided on the acid supply pipe 31 ; when a bypass pipe 36 is connected to the acid supply pipe 31 , the bypass connection point of the bypass pipe 36 is preferably located at the outlet side of the heater 34 .

[0028] In one embodiment, a cleaning unit and a strip surface drying unit are connected in series downstream of the final pickling treatment unit 1, so that the surface of the strip after pickling can be cleaned and dried. The cleaning unit preferably adopts a multi-stage countercurrent cascade cleaning unit, and the strip surface drying unit includes but is not limited to a hot air drying device.

[0029] Except for the first and last circulating acid tanks 2, it is preferred that the remaining circulating acid tanks 2 are all offline acid tanks.

[0030] The concentration of the acid solution decreases in sequence from the final pickling treatment unit 1 to the initial pickling treatment unit 1 .

[0031] In one embodiment, the pickling system uses hydrochloric acid as the acid solution.

[0032] Example 2

[0033] An embodiment of the present invention provides a method for using the above pickling treatment system, including:

[0034] According to the pickling working conditions, select the offline acid tank for pickling work to meet the corresponding pickling requirements.

[0035] Wherein, the off-line acid tank quantity that drops into pickling work can be 0, also can be that all off-line acid tanks all drop into pickling work, even if also all off-line acid tanks all off-line, or at least part off-line acid tank is online.Because the acid solution concentration of each circulation acid tank 2 is different, therefore, select to drop into the position of off-line acid tank, namely control the combination of the circulation acid tank 2 that drops into pickling work, can reach different pickling effects.

[0036] For the circulating acid tank 2 to be taken offline, the first control valve 211 on the corresponding override pipe 21 is opened, and the corresponding second control valve 22 is closed.

[0037] For the offline circulating acid tank 2, its corresponding pickling treatment unit 1 is also offline, that is, it is temporarily isolated from the strip production; wherein, when the pickling treatment unit 1 is offline, it can be selected to empty the pickling treatment unit 1, or lower the liquid level in the pickling treatment unit 1, or make the pickling treatment unit 1 have no acid flow, according to the sensitivity of the strip to the acid solution.

[0038] In one of them embodiment, for off-line circulation acid tank 2, still by the acid supply pump 35 on its acid supply pipe 31 with acid solution pump to well heater 34 in the tank, the acid solution after the heating flows back to the circulation acid tank 2 by bypass pipe 36, can guarantee the temperature of acid solution in the tank like this, guarantees that it can be put into production immediately when follow-up is online.In addition, for the upper level circulation acid tank 2 of off-line circulation acid tank 2 (when for example third level circulation acid tank 2 is off-line, upper level circulation acid tank is second level circulation acid tank 2), according to the sensitivity of band to acid solution concentration, can select to mend acid or make up water in this upper level circulation acid tank 2 to control the acid solution concentration in this upper level circulation acid tank 2.

[0039] Taking the pickling treatment system shown in Figure 1 as an example, the following working conditions are included:

[0040] (1) The pickling treatment units 1 of No. 1 to No. 4 are all put into pickling operation, the first control valves 211 on the respective transcending pipes 21 are all closed, and the second control valves 22 are all opened. At this time, fresh acid is supplied to the No. 4 circulating acid tank 2, and flows through the No. 3 circulating acid tank 2, the No. 2 circulating acid tank 2 and the No. 1 circulating acid tank 2 in sequence.

[0041] (2) Close the second control valve 22 of the NO.2 circulating acid tank 2 and open the first control valve 211 on the override pipe 21 of the NO.2 circulating acid tank 2; all the first control valves 211 on the other override pipes 21 are closed, and the second control valves 22 of the NO.3 circulating acid tank 2 are opened, so that the NO.2 pickling treatment unit 1 can be temporarily isolated from the strip production, and the NO.1 circulating acid tank 2, the NO.3 circulating acid tank 2 and the NO.4 pickling treatment unit 1 are all put into pickling operation. The acid supply pump 35 of the NO.2 circulating acid tank 2 can be opened or closed.

[0042] (3) Close the second control valve 22 of the NO.3 circulating acid tank 2 and open the first control valve 211 on the override pipe 21 of the NO.3 circulating acid tank 2; all the first control valves 211 on the other override pipes 21 are closed, and the second control valves 22 of the NO.2 circulating acid tank 2 are opened, so that the NO.3 pickling treatment unit 1 can be temporarily isolated from the strip production, and the NO.1 circulating acid tank 2, the NO.2 circulating acid tank 2 and the NO.4 pickling treatment unit 1 are all put into pickling operation. The acid supply pump 35 of the NO.3 circulating acid tank 2 can be opened or closed.

[0043] (4) Close the second control valve 22 of the NO.2 circulating acid tank 2 and the NO.3 circulating acid tank 2, and open the first control valve 211 on the override pipe 21 of the NO.2 circulating acid tank 2 and the NO.3 circulating acid tank 2; the NO.2 pickling treatment unit 1 and the NO.3 pickling treatment unit 1 can be temporarily isolated from the strip production, and the NO.1 circulating acid tank 2 and the NO.4 pickling treatment unit 1 can both be put into pickling operation. The acid supply pump 35 of the NO.2 circulating acid tank 2 and the NO.3 circulating acid tank 2 can be opened or closed.

[0044] (5) If production needs to be suspended urgently, for example, if working condition 1 needs to be stopped suddenly, the drain valves on the drain pipes 33 are automatically opened to achieve rapid emptying of the pickling treatment units 1, thereby preventing excessive corrosion of the strip stopped in the pickling treatment units 1. The control valves on the bypass pipes 36 configured for the circulating acid tanks 2 are automatically opened, and the control valves on the acid supply pipes 31 are closed. The acid solution in the circulating acid tanks 2 is pumped to the heater 34 through the acid supply pumps 35, and the heated acid solution is refluxed into the circulating acid tanks 2 through the bypass pipes 36.

[0045] Example 3

[0046] This embodiment further optimizes the above-mentioned embodiment 1 / embodiment 2.

[0047] In each pickling treatment unit 1, at least part of the pickling treatment units 1 adopts a pickling tank 1 with inductive hydrogen control.

[0048] As shown in Figures 2 and 3, for the pickling tank 1 with inductive hydrogen control, at least one inducer 6 is provided on the pickling tank 1, and the inducer 6 has an air inlet, an air supply port and a return air port. The air inlet is connected to an air supply pipe 61, and the air supply port and the return air port are both connected to the tank cavity of the pickling tank 1. At least part of the return air ports of the inducers 6 are arranged corresponding to the hydrogen enrichment area of ​​the pickling tank 1.

[0049] Preferably, the inductor 6 is arranged on the top of the pickling tank 1 .

[0050] Preferably, multiple inductors 6 are arranged to improve the control effect and efficiency of the hydrogen concentration in the tank. Preferably, at least some of the inductors 6 are arranged in the hydrogen-enriched area of ​​the pickling tank 1, for example, opening at the top of the tank in the hydrogen-enriched area and docking with the return air port of the inductor 6, or connecting through a return air duct.

[0051] Preferably, the pickling tank 1 is provided with an exhaust port connected to an acid mist extraction mechanism 7. Optionally, the exhaust port is provided on the side of the pickling tank 1. In one embodiment, as shown in FIG2 , the acid mist extraction mechanism 7 includes an acid mist collection pipe, a washing tower 71 disposed on the acid mist collection pipe, and a centrifugal fan. The spray mechanism in the washing tower 71 performs demisting and simultaneously recovers the acid solution.

[0052] In this embodiment, an inducer 6 is provided to extract the gas in the pickling tank 1 and then send it back into the tank. On the one hand, it can change the gas distribution in the tank, improve the gas fluidity in the tank, and prevent hydrogen enrichment. On the other hand, it can also dilute the atmosphere in the tank, thereby reducing the possibility of hydrogen combustion and hydrogen explosion in the tank, and effectively improving production safety.

[0053] In one embodiment, the gas supply pipe 61 supplies an inert gas to dilute the atmosphere in the tank and prevent hydrogen explosion. The inert gas includes but is not limited to nitrogen.

[0054] In one embodiment, the air supply jet outputted from the air supply port adopts at least one of the following forms:

[0055] (1) The air supply jet is directed toward the hydrogen-rich area to drive the hydrogen in the tank to the exhaust port of the pickling tank 1, thereby increasing the mobility of the hydrogen and making it easier for the hydrogen to be discharged out of the tank;

[0056] (2) The air supply jet is directed toward the periphery of the hydrogen-enriched area, and is used to form a negative pressure suction effect on the hydrogen-enriched area. The negative pressure effect generated by the jet can suck the hydrogen in the hydrogen-enriched area and increase the mobility of the hydrogen;

[0057] It can be seen that in this embodiment, the air supply power of the inducer 6 can further achieve the hydrogen control effect, and at the same time can also save the exhaust energy consumption of the pickling tank 1.

[0058] Preferably, the air supply port should be staggered with the air exhaust port to avoid airflow short-circuiting. The air supply jet is preferably staggered with the return air port.

[0059] In one embodiment, as shown in FIG3 , a first adsorbent layer 64 is provided in the return air duct 62 of the inductor 6. Preferably, the first adsorbent layer 64 is mainly used to absorb acid mist in the return air. For example, the first adsorbent layer 64 uses SDG adsorbent or activated carbon adsorbent.

[0060] Among them, there can be multiple return air ports / return air channels 62 in the inducer 6, which can increase the processing capacity.

[0061] In one embodiment, as shown in FIG3 , a second adsorbent layer 65 is further provided in the return air channel 62 of the inducer 6 . The second adsorbent layer 65 is located downstream of the first adsorbent layer 64 , that is, the second adsorbent layer 65 is located on the side of the first adsorbent layer 64 away from the return air outlet. The return air is processed by the first adsorbent layer 64 and the second adsorbent layer 65 in sequence.

[0062] In one embodiment, the second adsorbent layer 65 uses an adsorbent that can adsorb hydrogen, including but not limited to high specific surface area activated carbon or carbon nanotubes.

[0063] Based on the above scheme, hydrogen adsorption is achieved in the inductor 6. The low hydrogen concentration in the supply air jet effectively reduces the hydrogen concentration within the tank, significantly controlling hydrogen. The return air first passes through the first adsorbent layer 64 to absorb the acid mist before entering the second adsorbent layer 65 for hydrogen adsorption. This process is highly rational, ensuring effective hydrogen adsorption and reducing the load on the second adsorbent layer 65.

[0064] In one embodiment, as shown in FIG3 , a third adsorbent layer 66 is provided in the air supply duct 63 of the inductor 6 . Preferably, the third adsorbent layer 66 utilizes an adsorbent capable of adsorbing hydrogen, including but not limited to high-surface-area activated carbon or carbon nanotubes. This third adsorbent layer 66 also enables hydrogen adsorption. In particular, when both the second adsorbent layer 65 and the third adsorbent layer 66 are provided within the inductor 6 , the hydrogen adsorption effect can be further enhanced.

[0065] In one embodiment, as shown in Figure 3 , the induction device 6 includes a plenum box 67 and an induction box 68 . The air supply pipe 61 is connected to the plenum box 67 . An air inlet nozzle is provided at the outlet of the plenum box 67 , facing into the induction box 68 and injecting a jet of air into the induction box 68 to create a negative pressure. Both the return air inlet and the supply air inlet are provided on the induction box 68 . An air supply nozzle is provided at the outlet of the induction box 68 , facing into the pickling tank 1 and injecting a jet of air into the pickling tank 1 .

[0066] Among them, preferably, the spray angle of the air supply nozzle is adjustable, which can improve process flexibility.

[0067] In one embodiment, as shown in FIG2 , the pickling tank 1 is equipped with a hydrogen concentration detection unit 8 for detecting the hydrogen concentration in the tank. An induction control valve 611 is provided on the gas supply pipe 61. The hydrogen concentration detection unit 8 is preferably interlocked with the induction control valve 611 to facilitate automatic hydrogen control.

[0068] When used, specifically including:

[0069] The hydrogen concentration in the pickling tank 1 is detected. When the hydrogen concentration in the tank reaches a set threshold, the inductor 6 works to reduce the hydrogen concentration in the tank.

[0070] In one embodiment, when the hydrogen concentration in the tank reaches a first set threshold, the inductor 6 is operated to perform a preliminary hydrogen control operation;

[0071] When the hydrogen concentration in the tank reaches the second set threshold, the acid mist is extracted through the exhaust port to quickly reduce the hydrogen concentration in the tank. During this process, the inducer 6 can work synchronously.

[0072] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A pickling treatment system, characterized in that: It comprises at least three stages of pickling treatment units arranged in series, each of which is respectively provided with a circulating acid tank, and each of which is connected in series through a ladder flow pipe, wherein: The circulating acid tank of the first-stage pickling treatment unit is equipped with an acid discharge pipe. The circulating acid tank of the final pickling treatment unit is equipped with a new acid pipe. At least part of the remaining circulating acid tanks are offline acid tanks, which are equipped with an override pipe and an offline control valve group. Both ends of the override pipe are respectively connected to the ladder flow pipe section on the inlet and outlet sides of the offline acid tank. The offline control valve group includes a first control valve arranged on the override pipe and two second control valves respectively arranged on the ladder flow pipe section on the inlet and outlet sides. The second control valve is located between the offline acid tank and the corresponding side override pipe bypass connection point.

2. The pickling treatment system according to claim 1, characterized in that: The circulating acid tank is connected to the corresponding pickling treatment unit through an acid supply pipe and a reflux pipe, and a heater is provided on the acid supply pipe.

3. The pickling treatment system according to claim 2, characterized in that: The circulating acid tank is also provided with a bypass pipe, which is connected to the acid supply pipe section at the outlet side of the heater.

4. The pickling treatment system according to claim 1, characterized in that: A cleaning unit and a strip surface drying unit are connected in series downstream of the final pickling treatment unit.

5. The pickling treatment system according to claim 4, characterized in that: The cleaning unit adopts a multi-stage countercurrent cascade cleaning unit.

6. The method for using the pickling treatment system according to any one of claims 1 to 5, characterized in that: The method of use includes: According to the pickling working conditions, select the offline acid tank for pickling to meet the corresponding pickling requirements; for the circulating acid tank to be offline, open the first control valve on the configured override pipe and close the corresponding second control valve.

7. The method of use according to claim 6, characterized in that: For the offline circulating acid tank, the acid liquid in the tank is still pumped to the heater through the acid supply pump on its acid supply pipe, and the heated acid liquid flows back to the circulating acid tank through the bypass pipe to ensure the temperature of the acid liquid in the tank.

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