Alkali washing method for high-fluorine-chlorine zinc oxide powder

Abstract

The invention relates to a high fluorine chlorine zinc oxide powder alkali washing method, and belongs to the technical field of zinc hydrometallurgy high fluorine chlorine zinc oxide powder alkali washing, and the method comprises the following steps: S1, alkali liquor preparation; s2, alkali washing; s3, washing on a machine for the first time; s4, pulpifying and washing; s5, washing on the machine for the second time; the method comprises the following steps: preparing an alkali washing solution with a specific proportion for primary alkali washing, then directly carrying out filter pressing on a No.1 filter press, directly washing alkali washing residues after filter pressing on the No.1 filter press for primary washing, slurrying the obtained slurried and washed filter residues, and then carrying out filter pressing on the slurried and washed filter residues in a No.2 filter press. And the filter-pressed secondary machine washing filter residues are directly subjected to secondary machine washing and pressurized filter pressing, so that an alkali-washed product can be obtained, the method is simple to operate, and the washing mode of machine washing is quicker, simpler and more convenient.

Description

Technical Field

[0001] The present application relates to the technical field of alkali washing of high-fluorine and chlorine zinc oxide powder in zinc hydrometallurgy, and in particular to an alkali washing method of high-fluorine and chlorine zinc oxide powder. Background Art

[0002] As one of the important zinc secondary resource raw materials, secondary zinc oxide powder has a wide range of sources, mainly including bag dust, boiler dust, multi-chamber furnace dust, acid leaching slag rotary kiln volatile dust, blast furnace dust, converter dust, gas ash, smelting and hot-pressed zinc slag, waste zinc-manganese batteries, etc. This secondary zinc oxide powder usually contains high fluorine and chlorine (F0.1%~1.4%, Cl0.1%~5.0%). When leaching directly, fluorine and chlorine almost all enter the zinc sulfate solution, but the presence of fluorine and chlorine has a great impact on process equipment and environment. When the content reaches a certain level, it will even affect the consumption of cathodes and cathodes during electrolysis and the on-site working environment. Therefore, fluorine and chlorine in high-fluorine chlorine zinc oxide powder must be removed before leaching.

[0003] In the prior art, for the removal of fluorine and chlorine in the above-mentioned high-fluorine zinc oxide powder, the publication number CN117443915A discloses a method for ultrasonically removing fluorine and chlorine from high-fluorine zinc oxide dust. The method includes a first-stage alkali washing, a second-stage alkali washing, and subsequent treatment steps. The specific contents are as follows: A. First-stage alkali washing: slurry the high-fluorine zinc oxide dust and the second-stage alkali washing liquid at a liquid-solid ratio of 2 to 8 mL / g, and then place them in an ultrasonic environment at a temperature of 40 to 90°C and stir for alkali washing for 10 to 180 minutes. After the reaction is completed, the first-stage alkali washing liquid and the first-stage alkali washing liquid are separated by liquid and solid. A. second stage alkali washing: the first stage alkali washing residue and alkali solution are slurried and prepared at a liquid-solid ratio of 1.5-7 mL / g, and then placed in an ultrasonic environment at a temperature of 40-90°C for stirring and alkali washing for 10-180 min. After the reaction is completed, the second stage alkali washing liquid and the second stage alkali washing residue are obtained by liquid-solid separation; C. subsequent treatment: the second stage alkali washing liquid is returned to the first stage alkali washing step, the second stage alkali washing residue is washed with water for 2-4 times and then recycled into the lead-zinc system as a raw material for zinc oxide smoke. The first stage alkali washing liquid is evaporated and crystallized to produce an industrial salt product, and the evaporated salt liquid is returned to the second stage alkali washing step as a solvent for the alkali solution for recycling.

[0004] Although this method achieves the removal of fluorine and chlorine, it requires the following steps: a first-stage alkali washing under ultrasonic conditions, solid-liquid separation, evaporation and crystallization of the first-stage alkali washing liquid, a second-stage alkali washing under ultrasonic conditions, solid-liquid separation again, the second-stage alkali washing liquid returns to the first-stage alkali washing for reuse, and the second-stage alkali washing residue is washed with water 2 to 4 times to remove fluorine and chlorine from the high-fluorine and chlorine zinc oxide powder. From the above description, it can be seen that the alkali washing must be carried out under ultrasonic conditions, and the two alkali washing process steps are lengthy. After the second-stage alkali washing, 2 to 4 water washes are required to remove fluorine and chlorine from the residue.

[0005] Therefore, for the removal of fluorine and chlorine in high-fluorine and chlorine zinc oxide powder, providing an alkaline washing method with simple procedures and convenient washing methods on the basis of ensuring a certain fluorine and chlorine removal rate has always been a technical problem to be solved urgently by those skilled in the art. Summary of the invention

[0006] In order to solve or partially solve the problems existing in the related art, the purpose of the present invention is to provide an alkaline washing method with simple procedures and convenient washing methods by combining a filter press washing device while ensuring a certain fluorine and chlorine removal rate.

[0007] To achieve the above purpose, the present invention is implemented by the following technical scheme, which mainly includes alkali washing, one pulping water washing, and two on-machine washings. The specific contents are:

[0008] A method for alkali washing of high-fluorine chlorine zinc oxide powder comprises the following steps:

[0009] S1, alkali solution preparation: prepare clean water, sodium carbonate and sodium hydroxide according to a liquid-to-solid ratio of 2 to 3:1:1 (g / l) to form an alkali washing solution;

[0010] S2, alkali washing: washing the high-fluorine chlorine zinc oxide powder with an alkali washing solution, the end point pH is 8-10, and the alkali washing liquid and alkali washing residue are obtained after filter pressing, and the alkali washing residue is left on the No. 1 filter press;

[0011] S3, primary washing on the machine: on the No. 1 filter press, the alkali-washed residue is washed with clean water of 0.6 to 1.2 times the solid mass, and after washing, pressure filtering is applied to obtain a primary machine-washed liquid and a primary machine-washed filter residue;

[0012] S4, slurry washing: after the primary machine-washed filter residue is slurried, it is filtered by a No. 2 filter press to obtain a slurry-washed filter residue and a slurry-washed liquid, and the slurry-washed filter residue is left on the filter press;

[0013] S5, secondary machine washing: on the No. 2 filter press, the slurried water-washed filter residue is washed with clean water of 0.6 to 1.2 times the solid mass, and after washing, it is pressurized and filtered to obtain secondary machine washing liquid and secondary machine washing filter residue, which is the product after washing.

[0014] Optionally, after step S5, the following steps are further included:

[0015] S6, subsequent treatment: the first machine washing liquid is used in step S1, so that the first machine washing liquid, sodium carbonate and sodium hydroxide are configured into an alkaline washing liquid according to a liquid-to-solid ratio of 2 to 3:1:1 (g / l); a part of the slurry water washing liquid is used in step S3, and the alkaline washing residue is washed with slurry water washing liquid with a solid mass of 0.6 to 1.2 times; the first machine washing filter residue is slurried with another part of the slurry water washing liquid and the second machine washing liquid.

[0016] Optionally, when the F in the alkali-washed solution - The content is 4-20g / l or Cl - When the content is 40-120 g / l, the alkali-washed liquid is transported to a sewage treatment station for wastewater treatment. Otherwise, the alkali-washed liquid is returned to step S1 to replace clean water for alkali solution preparation.

[0017] Optionally, in step S2, in the No. 1 alkali washing device, the high-fluorine-chlorine zinc oxide powder is first slurried with clean water, the liquid-to-solid ratio of the high-fluorine-chlorine zinc oxide powder to the clean water is 3-5:1 (g / l), and then the alkali washing liquid is added for washing, the pH in the No. 1 alkali washing device is controlled at 9-11, the washing time is 1 hour, the slurry in the No. 1 alkali washing device overflows to the No. 2 alkali washing device, the alkali washing liquid is added to the No. 2 alkali washing device, the end point pH is kept stable at 8-10, and the washing time is 1 hour.

[0018] Optionally, the high-fluorine and chlorine zinc oxide powder is slurried with an alkali-washed liquid, and the liquid-to-solid ratio of the high-fluorine and chlorine zinc oxide powder to the alkali-washed liquid is 3 to 5:1 (g / l).

[0019] Optionally, the chemical composition of the high-fluorine oxychlorine zinc powder in step S2 is F0.1%-5%, Cl0.1%-10%, and Zn15%-55%.

[0020] Optionally, in step S4, the temperature during slurry washing is 60-80° C., and the stirring time is 30-120 min.

[0021] Optionally, in steps S3 and S5, the washing time used for the first on-machine washing and the second on-machine washing is 15 to 60 minutes.

[0022] Optionally, in steps S3 and S5, the pressure during filtration of the first machine-washed filter residue and the second machine-washed filter residue is 1.6 to 2.0 MPa.

[0023] Optionally, in steps S3 and S5, the moisture content of the first machine-washed filter residue and the second machine-washed filter residue after filtration is less than 20%.

[0024] The technical solution provided by this application may have the following beneficial effects:

[0025] 1. The present invention adopts an alkali washing process combining alkali washing and filter press washing equipment. Compared with the prior art, it is no longer necessary to perform alkali washing twice in an ultrasonic environment. It is only necessary to perform alkali washing once by configuring an alkali washing solution in a specific proportion, and then directly perform filter pressing on a No. 1 filter press, and directly perform an on-machine washing on the alkali washing residue after the filter pressing. The obtained slurry water-washed filter residue is slurried and then enters the No. 2 filter press for filter pressing again, and then the secondary machine-washed filter residue after the filter pressing is directly subjected to a secondary on-machine washing, and the alkali-washed product can be obtained by pressurizing the filter press. The method is simple to operate, and the on-machine washing method is faster and simpler;

[0026] By configuring an alkaline washing solution in a specific proportion, an alkaline washing is performed once, so that the F and Cl in the high-fluorine and chlorine zinc oxide powder enter the solution in the form of NaF and NaCl respectively, and then combined with the use of a filter press, through a slurry washing and two on-machine washings, the F and Cl mixed in the alkaline washing residue are fully washed into the solution, so that the fluorine and chlorine are removed, and the fluorine removal rate is ≥82%, and the chlorine removal rate is ≥96%;

[0027] 2. The present invention prepares alkaline solution by respectively preparing the alkaline washing liquid and the first machine washing liquid, uses a part of the pulped water washing liquid as washing liquid for the first machine washing, and uses the other part of the pulped water washing liquid and the second machine washing liquid to pulp the first machine washing residue. The technology is mature and reliable, and the water resource is saved.

[0028] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and other objects, features and advantages of the present application will become more apparent through a more detailed description of exemplary embodiments of the present application in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the present application.

[0030] Figure 1 It is a flowchart of a high-fluorine chlorine zinc oxide powder alkali washing method shown in an embodiment of the present application. DETAILED DESCRIPTION

[0031] The embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.

[0032] It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0033] In the description of the present application, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the tank or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0034] In order to make the objectives, technical solutions and beneficial effects of the present invention clearer, the preferred embodiments of the present invention will be described in detail below to facilitate understanding by technicians.

[0035] Embodiment 1:

[0036] The treated high-fluorine zinc oxychloride powder has a F content of 2.45% and a Cl content of 8.2%.

[0037] S1, alkali solution preparation: prepare clean water, sodium carbonate and sodium hydroxide according to a liquid-to-solid ratio of 2.5:1:1 (g / l) to form an alkali washing solution;

[0038] S2, alkali washing: washing the high-fluorine chlorine zinc oxide powder with an alkali washing solution, controlling the temperature of the whole process to be 83°C, and the end point pH to be 8-10. After the reaction is completed, alkali washing liquid and alkali washing residue are obtained by filter pressing, and the alkali washing residue is left on the No. 1 filter press;

[0039] S3, one-time on-machine washing: on the No. 1 filter press, clean water with a volume of 0.8 times the solid mass is pumped into the channels on both sides of the filter plate to wash the alkali-washed residue, so that the liquid and the alkali-washed residue are fully soaked. After washing for 30 minutes, the alkali-washed residue is filtered at a pressure of 1.6 MPa to obtain a first-machine washed liquid and a first-machine washed filter residue, and the residue contains 18% water;

[0040] S4, slurry washing: slurry the machine-washed filter residue with clean water, control the temperature to 70°C, stir for 60 minutes, and filter with a No. 2 filter press to obtain slurry-washed filter residue and slurry-washed liquid, and the slurry-washed filter residue remains on the filter press;

[0041] S5, secondary machine washing: on the No. 2 filter press, clean water with a solid mass of 0.8 times is pumped into the channels on both sides of the filter plate to wash the slurried water-washed filter residue. After washing for 30 minutes, the alkali-washed residue is filter-filtered at a pressure of 1.6 MPa to obtain secondary machine washing liquid and secondary machine washing filter residue. The residue contains 17.3% water. The secondary machine washing filter residue is the product after washing. The F content in the obtained secondary machine washing filter residue is 0.43%, and the Cl content is 0.31%.

[0042] After data analysis, it was found that the defluorination rate was 82.8% and the dechlorination rate was 96.3%.

[0043] Embodiment 2:

[0044] The treated high-fluorine zinc oxychloride powder has a F content of 3.18% and a Cl content of 7.31%.

[0045] S1, alkali solution preparation: prepare clean water, sodium carbonate and sodium hydroxide according to a liquid-to-solid ratio of 2.5:1:1 (g / l) to form an alkali washing solution;

[0046] S2, alkali washing: in the first alkali washing device, the high-fluorine chlorine zinc oxide powder is first slurried with clean water, the liquid-to-solid ratio of the high-fluorine chlorine zinc oxide powder and the clean water is 3:1 (g / l), and then the alkali washing solution is gradually added for washing, the pH in the first alkali washing device is controlled to be 11, the washing time is 1 hour, the slurry in the first alkali washing device overflows to the second alkali washing device, and clean water is added to the second alkali washing device for pH adjustment, and the end point pH is kept stable at 9.5. The washing time is 1 hour. After the reaction is completed, the alkali-washed liquid and alkali-washed residue are obtained by filter pressing, and the alkali-washed residue is left on the first filter press;

[0047] S3, one-time on-machine washing: on the No. 1 filter press, clean water with a volume of 0.8 times the solid mass is pumped into the channels on both sides of the filter plate to wash the alkali-washed residue, so that the liquid and the alkali-washed residue are fully soaked. After washing for 30 minutes, the alkali-washed residue is filtered at a pressure of 1.6 MPa to obtain a first-machine washed liquid and a first-machine washed filter residue, and the residue contains 18.5% water;

[0048] S4, slurry washing: slurry the first machine washing residue with clean water, the liquid-to-solid ratio of clean water to the first machine washing residue is 3:1 (g / l), control the temperature to 75°C, stir for 60 minutes, and filter with a No. 2 filter press to obtain a slurry washed residue and a slurry washed liquid, and the slurry washed residue is left on the filter press;

[0049] S5, secondary machine washing: on the No. 2 filter press, clean water with a solid mass of 0.8 times is pumped into the channels on both sides of the filter plate to wash the slurried water-washed filter residue. After washing for 30 minutes, the alkali-washed residue is filter-filtered at a pressure of 1.6 MPa to obtain secondary machine washing liquid and secondary machine washing filter residue. The residue contains 17.6% water. The secondary machine washing filter residue is the product after washing. The F content in the obtained secondary machine washing filter residue is 0.44% and the Cl content is 0.28%.

[0050] After data analysis, it can be seen that the defluorination rate is 86.44% and the dechlorination rate is 96.25%.

[0051] Embodiment 3:

[0052] The treated high-fluorine zinc oxychloride powder has a F content of 4.20% and a Cl content of 9.73%.

[0053] S1, alkali solution preparation: prepare clean water, sodium carbonate and sodium hydroxide according to a liquid-to-solid ratio of 3:1:1 (g / l) to form an alkali washing solution;

[0054] S2, alkali washing: in the first alkali washing device, the high-fluorine chlorine zinc oxide powder is first slurried with clean water, the liquid-to-solid ratio of the high-fluorine chlorine zinc oxide powder and the clean water is 3:1 (g / l), and then the alkali washing solution is gradually added for washing, the pH in the first alkali washing device is controlled to be 10.5, the washing time is 1 hour, the slurry in the first alkali washing device overflows to the second alkali washing device, and clean water is added to the second alkali washing device for pH adjustment, the end point pH is kept stable at 10, the washing time is 1 hour, after the reaction is completed, the alkali washing liquid and alkali washing residue are obtained by filter pressing, and the alkali washing residue is left on the first filter press;

[0055] F in the alkali washing solution - The content is 9.65g / l, Cl - The content is 25.99g / l, F - The content is not between 4 and 20 g / l and Cl - If the content is not between 40 and 120 g / l, the alkali-washed solution can be returned to step S1 to replace clean water for preparing the alkali solution.

[0056] S3, one-time on-machine washing: on the No. 1 filter press, clean water with a volume of 1.2 times the solid mass is pumped into the channels on both sides of the filter plate to wash the alkali-washed residue, so that the liquid and the alkali-washed residue are fully soaked. After washing for 30 minutes, the alkali-washed residue is filtered at a pressure of 1.6 MPa to obtain a first-machine washed liquid and a first-machine washed filter residue, and the residue contains 17.25% water;

[0057] S4, slurry washing: slurry the first machine washing residue with clean water, the liquid-to-solid ratio of clean water to the first machine washing residue is 3:1 (g / l), control the temperature to 78°C, stir for 60 minutes, and filter with a No. 2 filter press to obtain a slurry washed residue and a slurry washed liquid, and the slurry washed residue is left on the filter press;

[0058] S5, secondary machine washing: on the No. 2 filter press, clean water with a volume of 1.2 times the solid mass is pumped into the channels on both sides of the filter plate to wash the slurried water-washed filter residue. After washing for 40 minutes, the alkali-washed residue is filter-filtered at a pressure of 1.8 MPa to obtain secondary machine washing liquid and secondary machine washing filter residue. The residue contains 17.12% water. The secondary machine washing filter residue is the product after washing. The F content in the obtained secondary machine washing filter residue is 0.74% and the Cl content is 0.38%.

[0059] S6, subsequent treatment: the first machine washing liquid is used in step S1, so that the first machine washing liquid, sodium carbonate and sodium hydroxide are configured into an alkaline washing liquid according to a liquid-to-solid ratio of 2.5:1:1 (g / l); a part of the slurry water washing liquid is used in step S3, and the alkaline washing residue is washed with slurry water washing liquid with a solid mass of 3 times; the first machine washing filter residue is slurried with another part of the slurry water washing liquid and the second machine washing liquid, and the liquid-to-solid ratio during slurrying is 3 (g / l).

[0060] After data analysis, it can be seen that the defluorination rate is 82.73% and the dechlorination rate is 96.17%.

[0061] Comparative Example 1:

[0062] Compared with Example 1, other conditions remain unchanged, and two on-machine washings are no longer performed, that is, the alkali-washed slag obtained after step S2 is directly pulped and washed with water, and the first on-machine washing and the second on-machine washing are no longer performed.

[0063] The final alkali-washed product has an F content of 0.78% and a Cl content of 0.97%.

[0064] After data analysis, it can be seen that the defluorination rate is 68.8% and the dechlorination rate is 88.4%.

[0065] In Example 1, the defluorination rate of high-fluorine zinc oxide powder is 82.8%, and the dechlorination rate is 96.3%. By comparison, it can be shown that the on-machine washing method is not only faster and simpler, but also has a greater impact on the fluorine and chlorine removal rate of high-fluorine zinc oxide powder.

[0066] Finally, it should be noted that, in this article, relationships such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms include, include or any other variations are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0067] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A high-fluorine chlorine zinc oxide powder alkali washing method, characterized in that: The following steps are involved: S1, alkali solution preparation: prepare clean water, sodium carbonate and sodium hydroxide according to a liquid-to-solid ratio (g / l) of 2 to 3:1:1 to form an alkali washing solution; S2, alkali washing: washing the high-fluorine chlorine zinc oxide powder with an alkali washing solution, the end point pH is 8-10, and the alkali washing liquid and alkali washing residue are obtained after filter pressing, and the alkali washing residue is left on the No. 1 filter press; S3, primary washing on the machine: on the No. 1 filter press, the alkali-washed residue is washed with clean water of 0.6 to 1.2 times the solid mass, and after washing, pressure filtering is applied to obtain a primary machine-washed liquid and a primary machine-washed filter residue; S4, slurry washing: after the primary machine-washed filter residue is slurried, it is filtered by a No. 2 filter press to obtain a slurry-washed filter residue and a slurry-washed liquid, and the slurry-washed filter residue is left on the filter press; S5, secondary machine washing: on the No. 2 filter press, the slurried water-washed filter residue is washed with clean water of 0.6 to 1.2 times the solid mass, and after washing, it is pressurized and filtered to obtain secondary machine washing liquid and secondary machine washing filter residue, which is the product after washing.

2. The high-fluorine chlorine oxide zinc powder alkali cleaning method according to claim 1, characterized in that: After step S5, the following steps are also included: S6, subsequent treatment: the first machine washing liquid is used in step S1, so that the first machine washing liquid, sodium carbonate and sodium hydroxide are configured into an alkaline washing liquid according to a liquid-to-solid ratio of 2 to 3:1:1 (g / l); a part of the slurry water washing liquid is used in step S3, and the alkaline washing residue is washed with slurry water washing liquid with a solid mass of 0.6 to 1.2 times; the first machine washing filter residue is slurried with another part of the slurry water washing liquid and the second machine washing liquid.

3. The high-fluorine chlorine oxide zinc powder alkali cleaning method according to claim 1, characterized in that: When the F - The content is 4-20g / l or Cl - When the content is 40-120 g / l, the alkali-washed liquid is transported to a sewage treatment station for wastewater treatment. Otherwise, the alkali-washed liquid is returned to step S1 to replace clean water for alkali solution preparation.

4. The high-fluorine chlorine oxide zinc powder alkali cleaning method according to claim 1, characterized in that: In the step S2, in the first alkali washing device, the high-fluorine chlorine zinc oxide powder is first slurried with clean water, the liquid-to-solid ratio of the high-fluorine chlorine zinc oxide powder to the clean water is 3-5:1 (g / l), and then the alkali washing solution is added for washing, the pH in the first alkali washing device is controlled to be 9-11, the washing time is 1 hour, the slurry in the first alkali washing device overflows to the second alkali washing device, and the first machine washing liquid is added to the second alkali washing device to keep the end point pH stable at 8-10, and the washing time is 1 hour.

5. The high-fluorine chlorine oxide zinc powder alkali cleaning method according to claim 4, characterized in that: The high-fluorine zinc oxide powder is slurried with the alkali-washed liquid, and the liquid-to-solid ratio of the high-fluorine zinc oxide powder to the alkali-washed liquid is 3-5:1 (g / l).

6. The high-fluorine chlorine zinc oxide powder alkali cleaning method according to claim 1, characterized in that: The chemical composition of the high-fluorine zinc oxide powder in step S2 is F0.1%-5%, Cl0.1%-10%, and Zn15%-55%.

7. The high-fluorine chlorine zinc oxide powder alkali cleaning method according to claim 1, characterized in that: In step S4, the temperature during slurry washing is 60-80° C., and the stirring time is 30-120 min.

8. The high-fluorine chlorine zinc oxide powder alkali cleaning method according to claim 1, characterized in that: In the steps S3 and S5, the washing time for the first washing on the machine and the second washing on the machine is 15 to 60 minutes.

9. The high-fluorine chlorine oxide zinc powder alkali cleaning method according to claim 1, characterized in that: In the steps S3 and S5, the pressure during the filtration of the primary machine-washed filter residue and the secondary machine-washed filter residue is 1.6-2.0 MPa.

10. The high-fluorine chlorine zinc oxide powder alkali cleaning method according to claim 1, characterized in that: In the steps S3 and S5, the water content of the primary machine-washed filter residue and the secondary machine-washed filter residue after the filtration is less than 20%.

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