Post-treatment process for high-zinc material

Abstract

The invention belongs to the technical field of metallurgical industry solid waste treatment, and relates to a high-zinc material post-treatment process which comprises the following steps: step A, carrying out overall classification on high-zinc materials according to components and size characteristics, and separating and purifying the high-zinc materials with the mass fraction of metal zinc not lower than 90% by adopting a low-temperature liquation mode to obtain high-zinc materials; zinc liquid or crude zinc ingots are obtained; the method comprises the following steps: carrying out metal zinc separation and purification on a high-zinc material in which the mass fraction of metal zinc is less than 90% by adopting a high-temperature distillation mode to obtain zinc steam; and B, zinc dross generated in the low-temperature liquation process in the step A is sent to a high-temperature distillation process for metal zinc separation and purification, zinc steam obtained in the high-temperature distillation process is sent to the low-temperature liquation process to obtain zinc liquid or crude zinc ingots, and tailings in the high-temperature distillation process are sent out. The method solves the problems of long treatment flow, low metal recovery rate and poor economic benefit in the traditional high-zinc material treatment mode.

Description

Technical Field

[0001] The invention belongs to the technical field of solid waste disposal in the metallurgical industry and relates to a post-processing process for high-zinc materials. Background Art

[0002] The wet method accounts for about 90% of the zinc smelting process capacity. The zinc smelting process produces and discharges large amounts of solid waste in various types, including zinc slag, zinc ash (blue powder), volatile kiln dust, multi-chamber furnace ash and other high-zinc materials. It is estimated that for every ton of zinc produced, 0.96 tons of waste slag is emitted, of which the zinc content is as high as over 80%, and the particle size varies significantly from 0.1 microns to several hundred microns.

[0003] At present, the traditional recycling methods of high-zinc materials include pyrometallurgy, hydrometallurgy, magnetic separation, flotation and combined processes, which mainly have problems such as long process, high cost, difficulty in recycling and environmental pollution. The metal recovery rate is only 60% to 70%, and the elemental zinc in the tailings is 10% to 40%. In the case of increasingly tight zinc smelting raw materials, it is imperative to return high-zinc materials to the zinc smelting system as an important secondary resource.

[0004] Therefore, there is an urgent need for a new process with short process, high efficiency, environmental safety and stable products. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a high-zinc material post-processing process to solve the problems of long high-zinc material processing process, low metal recovery rate and poor economic benefits in traditional high-zinc material disposal methods.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A high-zinc material post-treatment process comprises the following steps:

[0008] Step A: Classify the high-zinc materials according to their composition and size characteristics, and separate and purify the high-zinc materials with a metal zinc mass fraction of not less than 90% by low-temperature melting to obtain zinc liquid or crude zinc ingots;

[0009] The high-zinc material in which the mass fraction of metallic zinc is less than 90% is separated and purified by high-temperature distillation to obtain zinc vapor;

[0010] Step B. The zinc slag produced in the low-temperature smelting process in step A is sent to a high-temperature distillation process for separation and purification of metallic zinc, the zinc vapor obtained in the high-temperature distillation process is sent to a low-temperature smelting process to obtain zinc liquid or crude zinc ingots, and the tailings of the high-temperature distillation process are sent out.

[0011] Furthermore, the tailings from the high temperature distillation process in step B are sent as return material to an upstream smelting system for reduction and enrichment, or directly sold as a product.

[0012] Furthermore, the high-zinc material is a zinc-containing material with a total zinc content greater than 90% and a metallic zinc content greater than 50%.

[0013] Furthermore, in step A, for materials with a metal zinc mass fraction lower than 90%, if the grain size of the material is lower than 10 μm, it is necessary to firstly perform a pressing process and then send it to a high-temperature distillation process.

[0014] Furthermore, in step B, the purity of the zinc liquid or crude zinc ingot obtained in the low-temperature smelting process is ≥98.7%, the mass fraction of zinc element in the tailings obtained in the high-temperature distillation process is ≥70%, and the evaporation rate of metallic zinc is ≥90%.

[0015] Furthermore, the zinc liquid or crude zinc ingot is subjected to electrolysis or distillation process to separate and purify various metals.

[0016] The beneficial effects of the present invention are:

[0017] 1. The present invention provides a high-zinc material post-processing process, which is different from the existing zinc smelting industry's disposal method for high-zinc solid waste in the factory. In view of the poor recycling rate of such high-zinc materials and the multi-point distribution characteristics in the factory, the original high-zinc materials are classified and planned, and high-temperature distillation and low-temperature smelting are used for joint disposal according to different zinc grades and particle sizes, and overall planning is carried out; at the same time, the unusable or low-value products produced by high-temperature distillation and low-temperature smelting are cross-jointly disposed at a deep level, which complement each other, and more reasonably dispose of the high-zinc solid waste generated in various processes of metallurgical enterprises, while achieving greater economic benefits.

[0018] 2. The present invention treats high-zinc solid waste by combining high-temperature distillation and low-temperature smelting. On the one hand, it can further improve the zinc extraction rate by about 20% or more on the basis of a single pyrometallurgical smelting treatment process (low-temperature smelting). At the same time, on the basis of a single high-temperature distillation treatment process, it performs molding pretreatment according to the particle size characteristics of the material, and couples the high-temperature distillation system with the low-temperature smelting system to ensure that the zinc product is stably output in the form of zinc liquid or crude zinc ingots, effectively solving the problem of zinc ash or blue powder generated in the circulation process of metallic zinc due to secondary oxidation or temperature control difficulties, and improving the economic value by more than 30%;

[0019] Secondly, by introducing the zinc vapor obtained in the high-temperature distillation process into the low-temperature smelting process, the zinc vapor phase change is fully utilized to continuously provide heat for the low-temperature smelting process, thereby reducing the energy consumption of the process and reducing the cost of recovering metallic zinc.

[0020] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0022] Figure 1 The figure is a process flow chart for post-processing of high-zinc materials. DETAILED DESCRIPTION

[0023] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0024] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0025] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0026] See also Figure 1 , which is a high-zinc material post-treatment process, specifically comprising the following steps:

[0027] A. The high-zinc materials produced in the production process of metallurgical enterprises are comprehensively classified according to their composition and size characteristics. Among them, the materials with a metal zinc mass fraction of not less than 90% are directly melted at low temperature to obtain zinc slag and zinc liquid or crude zinc ingots;

[0028] For materials with a metal zinc mass fraction of less than 90%, high-temperature distillation is used to separate and purify the metal zinc to obtain zinc vapor;

[0029] B. The zinc scum produced in the low-temperature smelting process in step A is sent to a high-temperature distillation process to separate and purify metallic zinc, the zinc vapor obtained in the high-temperature distillation process is sent to a low-temperature smelting process, and the zinc liquid or crude zinc ingot obtained in the low-temperature smelting process is subjected to an electrolysis or distillation process to separate and purify various metals;

[0030] C. The tailings from the high-temperature distillation process in step B are returned to the upstream smelting system as return material for reduction and enrichment, or directly sold as products.

[0031] The tailings are crude zinc oxide, specifically crude zinc oxide powder; the upstream smelting system includes a pyrometallurgical reduction system or a hydrometallurgical reduction system, etc.

[0032] The present invention disposes of high-zinc materials such as zinc slag, zinc ash or blue powder that cannot be directly utilized in various processes of the metallurgical enterprise through a cross-process combination method, which complements each other and disposes of high-zinc solid waste of the metallurgical enterprise more reasonably, while achieving greater economic benefits.

[0033] Specifically, the high-zinc material is a zinc-containing material with a total zinc content greater than 90% and a metallic zinc content greater than 50%. In step A, for materials with a metallic zinc mass fraction lower than 90%, if the material grain size is lower than 10 μm, it needs to be pressed and formed before being sent to a high-temperature distillation process.

[0034] In this embodiment, the purity of the zinc liquid or crude zinc ingot obtained in the low-temperature smelting process in step B is ≥98.7%, the mass fraction of zinc element in the tailings obtained in the high-temperature distillation process in step C is ≥70%, and the evaporation rate of metallic zinc is ≥90%; and the zinc vapor obtained in the high-temperature distillation process is introduced into the low-temperature smelting process, and the phase change of zinc vapor is fully utilized to continuously supplement heat for the low-temperature smelting process, thereby reducing the energy consumption of the process and reducing the cost of recovering metallic zinc.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A high-zinc material post-treatment process, characterized in that: The following steps are involved: Step A: Classify the high-zinc materials according to their composition and size characteristics, and separate and purify the high-zinc materials with a metal zinc mass fraction of not less than 90% by low-temperature melting to obtain zinc liquid or crude zinc ingots; The high-zinc material in which the mass fraction of metallic zinc is less than 90% is separated and purified by high-temperature distillation to obtain zinc vapor; Step B. The zinc slag produced in the low-temperature smelting process in step A is sent to a high-temperature distillation process for separation and purification of metallic zinc, the zinc vapor obtained in the high-temperature distillation process is sent to a low-temperature smelting process to obtain zinc liquid or crude zinc ingots, and the tailings of the high-temperature distillation process are sent out.

2. The high-zinc material post-treatment process according to claim 1, characterized in that: The tailings from the high-temperature distillation process in step B are sent as return material to the upstream smelting system for reduction and enrichment, or directly sold as products.

3. The high-zinc material post-treatment process according to claim 1, characterized in that: The high-zinc material is a zinc-containing material with a total zinc content greater than 90% and a metallic zinc content greater than 50%.

4. The high-zinc material post-treatment process according to claim 1, characterized in that: In step A, for materials with a metal zinc mass fraction lower than 90%, if the grain size of the material is lower than 10 μm, it needs to be pressed and formed before being sent to the high-temperature distillation process.

5. The high-zinc material post-treatment process according to claim 1, characterized in that: In the step B, the purity of the zinc liquid or the crude zinc ingot obtained in the low-temperature smelting process is ≥98.7%, the mass fraction of zinc element in the tailings obtained in the high-temperature distillation process is ≥70%, and the evaporation rate of metallic zinc is ≥90%.

6. The high-zinc material post-treatment process according to claim 1, characterized in that: The zinc liquid or crude zinc ingot is subjected to electrolysis or distillation process to separate and purify various metals.

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