A method for harmlessly treating hazardous waste residues containing arsenic oxide and sulfur and recovering arsenic oxide
Through the gradual physical separation method, the arsenic oxide-containing and sulfur hazardous waste residues are separated into elemental sulfur and arsenic trioxide, which solves the problems of difficulty in treating arsenic hazardous waste residues, resource recycling and environmental pollution in the existing technology, and realizes harmless treatment and resource recycling , the obtained materials have wide application value.
Patent Information
- Application Number
- CN202211648991.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-12-21
- Publication Date
- 2024-12-06
- Estimated Expiration
- 2042-12-21
AI Technical Summary
The treatment of hazardous arsenic-containing waste residue in the prior art is mostly curing treatment, and resource recycling cannot be carried out. The fire method and wet method are only suitable for arsenic slag with large amounts and low arsenic taste, which leads to a small amount of arsenic slag and difficult to treat and the environment. Pollution and complex system and high cost issues.
The gradual physical separation method is used to separate the arsenic oxide and sulfur hazardous waste residue into elemental sulfur and arsenic trioxide. By mixing carbon disulfide and heating purification, smoke-free gas generation and resource recovery are achieved.
The harmless disposal of arsenic-containing hazardous waste residue and the recovery of arsenic oxide are achieved, secondary pollution is avoided, and the obtained elemental sulfur and arsenic trioxide are of wide use and of great economic value.
Smart Images
Figure CN116099852B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of harmless treatment of hazardous waste residue containing arsenic, and specifically relates to a method for harmless treatment of hazardous waste residue containing arsenic oxide and sulfur and recovery of arsenic oxide. Background Art
[0002] At present, there are three main treatment processes for the disposal of arsenic-containing waste residues: solidification, pyrometallurgy and hydrometallurgy. The solidification method mainly solidifies and landfills arsenic residues with low arsenic content and difficult to recycle, and disposes of the arsenic residue harmlessly. Pyrometallurgy and hydrometallurgy mainly use arsenic residues with large amounts and low arsenic content to recycle and extract white arsenic. However, it is difficult to treat a variety of arsenic-containing waste residues with small amounts at present, which makes it difficult for production enterprises and also brings great pressure to environmental protection. Chinese patent CN 103755169A discloses a method for treating arsenic-containing waste residues by a cement rotary kiln. The invention mainly mixes arsenic-containing waste residues with cement raw materials and uses cement rotary kilns to prepare cement clinker. This method is not suitable for treating arsenic-containing waste residues with high arsenic content, and it is only a solidification treatment, without recycling arsenic and valuable metals, resulting in a waste of resources. Chinese patent CN 106222398A discloses a method for deep arsenic removal by roasting of arsenic-containing materials. The invention mainly involves mixing arsenic-containing materials, chlorinating agents and water into granules, and then sending them into a roasting furnace for roasting. Arsenic is removed in the form of arsenic chloride, thereby deeply removing arsenic from the arsenic-containing materials. However, after the arsenic chloride is removed, it will still exist in the smoke and dust, and will not be finally disposed of or utilized, and will still pollute the environment. Chinese patent CN111733329 A discloses a system and method for preparing metallic arsenic from the resource utilization of various arsenic slags. The system includes a volatilization furnace, a waste heat boiler, a cyclone dust collector, a reduction furnace, a condenser, a bag filter and a desulfurization device. The invention can simultaneously process various arsenic slag hazardous wastes, solve the problem of difficult treatment of small amounts of arsenic slag, and effectively obtain high-quality metallic arsenic and zinc oxide from resources, recover valuable metals in arsenic-containing waste slags, and maximize resource utilization. The invention system is complex and costly. In summary, finding new methods to harmlessly treat arsenic-containing hazardous waste residues has become a research topic that needs to be urgently addressed today.
[0003] Through the above analysis, the problems and defects of the prior art are as follows:
[0004] (1) The existing technologies for treating arsenic-containing hazardous waste slag mostly use solidification treatment methods, which cannot recycle resources. The pyrometallurgical and hydrometallurgical methods are only suitable for recycling large amounts of arsenic slag with low arsenic content, and are difficult to treat small amounts of arsenic slag.
[0005] (2) The existing improved technologies still have problems in the process of harmlessly treating various arsenic slag hazardous wastes, such as incomplete disposal, environmental pollution, complex systems and high costs. Summary of the invention
[0006] In view of the above technical problems in the existing treatment of arsenic-containing hazardous waste residues, the present invention proposes a method for harmlessly treating hazardous waste residues containing arsenic oxide and sulfur and recovering arsenic oxide. The harmless treatment of arsenic-containing hazardous waste residues is achieved through a step-by-step physical and chemical separation method, and elemental sulfur and arsenic trioxide are obtained without generating smoke or secondary pollution.
[0007] The present invention is achieved by a method for harmlessly treating hazardous waste residue containing arsenic oxide and sulfur and recovering arsenic oxide, comprising the following steps:
[0008] Step 1: Weigh the arsenic-containing waste residue according to weight, and dry it for later use;
[0009] Step 2: Mix the waste residue in step 1 with carbon disulfide in a ratio of 1:2 to 1:4 at 50°C to 55°C, slowly stir and mix, and soak in this state for 6 to 12 hours, then separate the mixture to remove sulfur; distill the carbon disulfide in which sulfur is dissolved to obtain elemental sulfur; the distilled carbon disulfide can be reused;
[0010] Step 3: heating the separated solid waste in a sealed container to sublime the arsenic trioxide, purify and separate the arsenic trioxide;
[0011] Step 4: Wash the remaining small amount of solid with alkaline solution to remove the residual arsenic oxides and separate the copper oxides.
[0012] Furthermore, the arsenic-containing waste slag in step 1 is mainly composed of sulfur, arsenic trioxide, and a small amount of copper-containing compounds.
[0013] Furthermore, the distillation in step 2 needs to meet the following conditions: temperature 50°C to 60°C, boiling point of carbon disulfide 46.5°C, boiling point of sulfur 444.6°C.
[0014] Furthermore, in the step three, the temperature of the separated solid waste residue is controlled at 195°C to 200°C during heating.
[0015] In combination with the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solutions to be protected by the present invention are as follows:
[0016] The present invention provides a method for harmlessly treating hazardous waste residues containing arsenic oxide and sulfur and recovering arsenic oxide. The arsenic-containing waste residues are mainly composed of sulfur, arsenic trioxide, and a small amount of copper-containing compounds. They can be separated step by step by physical and chemical methods to achieve the recovery of arsenic compounds while treating hazardous waste residues, turning waste into treasure and maximizing the utilization of mineral resources. The present invention achieves harmless disposal of arsenic-containing hazardous waste residues through a step-by-step physical and chemical separation method and obtains elemental sulfur and arsenic trioxide, and no smoke is generated, and no secondary pollution is generated. The two materials obtained have a wide range of uses and can generate huge economic value. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It is a flow chart of a method for harmlessly treating hazardous waste residue containing arsenic oxide and sulfur and recovering arsenic oxide provided by an embodiment of the present invention;
[0018] Figure 2 It is a phase analysis data diagram of arsenic-containing hazardous waste residue raw materials provided by an embodiment of the present invention. DETAILED DESCRIPTION
[0019] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.
[0020] In order to enable those skilled in the art to fully understand how to implement the present invention in detail, this section is an explanatory embodiment that expands and describes the technical solution of the claims.
[0021] The embodiment of the present invention provides a method for harmlessly treating hazardous waste residues containing arsenic oxide and sulfur and recovering arsenic oxide. The arsenic-containing waste residues are mainly composed of sulfur, arsenic trioxide, and a small amount of copper-containing compounds. They can be separated step by step by physical and chemical methods, so that arsenic compounds can be recovered while treating hazardous waste residues, turning waste into treasure and maximizing the utilization of mineral resources. The embodiment of the present invention achieves harmless disposal of arsenic-containing hazardous waste residues through a step-by-step physical and chemical separation method and obtains elemental sulfur and arsenic trioxide, without generating smoke and causing secondary pollution. The two materials obtained have a wide range of uses and can generate huge economic value.
[0022] like Figure 1 As shown, the method for harmlessly treating hazardous waste slag containing arsenic oxide and sulfur and recovering arsenic oxide provided by the embodiment of the present invention is prepared according to the following mass percentage ratio, and the steps are as follows:
[0023] S101: Weigh the arsenic-containing waste residue according to weight, and dry it for later use.
[0024] S102: Mix the waste residue in S101 with carbon disulfide in a ratio of 1:2 at 50°C, slowly stir and mix, and soak in this state for 6 hours, then separate the mixture and remove the sulfur; distill the carbon disulfide containing dissolved sulfur (temperature 50°C, boiling point of carbon disulfide 46.5°C, boiling point of sulfur 444.6°C) to obtain elemental sulfur; the distilled carbon disulfide can be reused.
[0025] S103: heating the separated solid waste in a sealed container at a temperature of 195° C. to sublimate arsenic trioxide, purify and separate arsenic trioxide;
[0026] S104: Wash the remaining small amount of solid with alkaline solution to remove the residual arsenic-containing oxides and separate the copper-containing oxides.
[0027] like Figure 2 As shown, it is a phase analysis data diagram of arsenic-containing hazardous waste residue raw materials provided in an embodiment of the present invention.
[0028] The test results of the embodiments of the present invention are shown in Table 1 below.
[0029] Table 1 Harmless treatment test table of hazardous waste residues containing arsenic oxide and sulfur
[0030]
[0031]
[0032] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.
Claims
1. A method for harmlessly treating hazardous waste residues containing arsenic oxide and sulfur and recovering arsenic oxide, characterized in that: Through the gradual physical and chemical separation method, the harmless disposal of arsenic-containing hazardous waste residues is achieved and elemental sulfur and arsenic trioxide are obtained; The following steps are involved: Step 1: Weigh the arsenic-containing waste residue according to weight, and dry it for later use; Step 2: Mix the waste residue in step 1 with carbon disulfide in a ratio of 1:2 to 1:4 at 50°C to 55°C, slowly stir and mix, and soak in this state for 6 to 12 hours, then separate the mixture to remove sulfur; distill the carbon disulfide in which sulfur is dissolved to obtain elemental sulfur; the distilled carbon disulfide can be reused; Step 3: heating the separated solid waste in a sealed container to sublime the arsenic trioxide, purify and separate the arsenic trioxide; Step 4: washing the remaining small amount of solid with alkaline solution to remove the residual arsenic oxides and separate the copper oxides; The arsenic-containing waste residue in step 1 is mainly composed of sulfur, arsenic trioxide, and a small amount of copper-containing compounds; The distillation in step 2 needs to meet the following conditions: temperature 50°C to 60°C, boiling point of carbon disulfide 46.5°C, boiling point of sulfur 444.6°C; In the step 3, the temperature of the separated solid waste residue is controlled at 195°C to 200°C when heated; No smoke is generated and no secondary pollution occurs.