Method for preparing copper-nickel-iron powder by co-chlorination and separation of copper-nickel slag / incineration fly ash

Abstract

The application discloses a method for preparing copper-nickel-iron-containing powder by co-chlorination and separation of copper-nickel slag and incineration fly ash, and comprises the following steps: after copper-nickel slag and incineration fly ash are uniformly mixed after being prepared and mixed, the mixture is balling to obtain green balls; the green balls are put into a chlorination and separation reactor to perform chlorination and separation roasting; the roasted balls are directly quenched with water and finely ground, and then the copper-nickel-iron-containing powder can be obtained through magnetic separation. The method fully utilizes the characteristics of high chlorine content and carbon content of the incineration fly ash, uses the incineration fly ash as a chlorinating agent and a reducing agent, and realizes the resource utilization of the copper-nickel slag / incineration fly ash, so that waste is turned into treasure, and the copper-nickel-iron-containing powder obtained can provide high-quality furnace charge for smelting weather-resistant steel. The method has simple process, strong operability and good application prospect.

Description

Technical Field

[0001] This invention relates to a method for the resource utilization of copper-nickel slag / incineration fly ash, specifically a method for the co-chlorination and separation of copper-nickel slag / incineration fly ash to prepare copper-nickel-iron powder, thereby achieving complete detoxification and resource utilization of fly ash, belonging to the field of metallurgical environmental protection technology. Background Technology

[0002] Salts (mainly sodium chloride, calcium chloride, and chlorinating agents) in incineration fly ash are a key factor affecting its harmless treatment and resource utilization. During fly ash solidification / stabilization treatment, the slow dissolution of soluble chlorides can easily cause the solidified body to break down, reducing structural strength and even causing landfill collapse, increasing the toxicity and risk of heavy metal leaching. During the melting / sintering process, the volatilization of soluble salts in fly ash at high temperatures promotes the volatilization of heavy metals, generating pollution such as salt spray. In the co-processing process in cement kilns, fly ash directly enters the cement kiln, where chlorides can easily cause scaling and blockage, and high chloride content can lead to cement that does not meet national standards. Currently, the main method for treating salts in incineration fly ash is water washing, but this process consumes a large amount of water, dechlorinates incompletely, and requires further wastewater treatment. Directly utilizing the salts in incineration fly ash could provide a completely new approach to the harmless treatment and resource utilization of fly ash.

[0003] Copper-nickel slag is an industrial waste residue after copper extraction. Its main components include valuable metals such as fir olivine, magnetite, copper matte, and nickel. Producing 1 ton of copper generates 2.2 tons of copper-nickel slag. Currently, the large-scale stockpiling of copper-nickel slag not only occupies a large area of ​​land but also pollutes the environment. Copper-nickel slag contains a large amount of valuable resources such as copper, nickel, and iron, but its complex properties make comprehensive recovery technically challenging. On the other hand, when processing low-grade, difficult-to-process mineral resources and secondary resources, various metals and their oxides, sulfides, and other complex compounds can, under certain conditions, form metal chlorides with significantly different chemical reactivity with chlorine, thereby achieving metal extraction and separation. Since the successful application of chlorination separation technology in the 1970s to process low-grade oxide ores, metallurgists have consistently considered it the most economical method for processing nickel laterite ore. Common chlorinating agents in chlorination separation are sodium chloride and calcium chloride, while coal is a common reducing agent.

[0004] Therefore, by making full use of the component characteristics of incineration fly ash and copper-nickel slag, the chlorination separation process is expected to achieve the synergistic resource utilization of incineration fly ash / copper-nickel slag. Summary of the Invention

[0005] To address the challenge of resource utilization of copper-nickel slag and incineration fly ash, this invention aims to provide a method for preparing copper-nickel-iron powder through co-chlorination separation of copper-nickel slag and incineration fly ash. The method involves finely grinding copper-nickel slag and incineration fly ash, mixing them evenly, pelletizing them to obtain green pellets, and then feeding these green pellets into a chlorination separation reactor for chlorination separation roasting. The roasted pellets are then directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder. By controlling the proportions and chlorination separation conditions, the co-chlorination separation of copper-nickel slag and incineration fly ash can be achieved.

[0006] The specific technical solution adopted in this invention is as follows:

[0007] A method for preparing copper-nickel-iron powder by co-chlorination separation of copper-nickel slag / incineration fly ash, the method comprising the following steps: finely ground copper-nickel slag and incineration fly ash are mixed at a mass ratio of 1:(0.5-2.5) and pelletized to obtain green pellets; the green pellets are fed into a chlorination separation reactor for chlorination separation roasting; the roasted pellets are directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder.

[0008] Preferably, the finely ground copper-nickel slag and incineration fly ash are mixed at a mass ratio of 1:(0.8-1.5).

[0009] Preferably, the calcination temperature is 950–1050°C, and the calcination time is 1–1.5 h.

[0010] Preferably, the moisture content of the green bulbs is 10% to 12%.

[0011] Preferably, the magnetic field strength of the magnetic separation is 1000 Gs to 1200 Gs.

[0012] Compared with the prior art, the beneficial effects of the technical solution of the present invention are as follows:

[0013] This invention proposes a resource utilization approach for preparing copper-nickel-iron powder through co-chlorination separation of copper-nickel slag and incineration fly ash. Finely ground copper-nickel slag and incineration fly ash are mixed evenly, pelletized, and then fed into a chlorination separation reactor for chlorination separation roasting. The roasted pellets are then directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder. Extensive experiments show that by optimizing the system—with a mass ratio of finely ground copper-nickel slag to incineration fly ash of 1:(0.5–2.5), a chlorination separation roasting temperature of 900–1200℃, and a chlorination separation roasting time of 0.5–2 h—co-chlorination separation of copper-nickel-iron in the copper-nickel slag and incineration fly ash system can be achieved.

[0014] On the one hand, this invention uses incineration fly ash as both the chlorinating and reducing agent in the chlorination separation process, eliminating the need for any external additives. Simultaneously, during the co-chlorination separation process, copper, nickel, and iron elements can be recovered from both the fly ash and copper-nickel slag, achieving high metal recovery rates by removing heavy metals from the fly ash. On the other hand, the high-temperature roasting process decomposes dioxins in the incineration fly ash, achieving complete detoxification.

[0015] This invention offers multiple benefits, achieving complete detoxification of incineration fly ash in one step, enabling the efficient and synergistic resource utilization of copper-nickel slag and incineration fly ash, and providing high-quality furnace feed for smelting weathering steel with the obtained copper-nickel-iron powder. This invention transforms waste into treasure, demonstrating significant economic and environmental benefits. Detailed Implementation

[0016] The present invention will be further described in detail below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0017] Example 1

[0018] A method for preparing copper-nickel-iron powder by co-chlorination separation of copper-nickel slag / incineration fly ash, the method comprising the following steps: finely ground copper-nickel slag and incineration fly ash are mixed at a mass ratio of 1:1 and mixed evenly to form green pellets; the green pellets are fed into a chlorination separation reactor for chlorination separation roasting; the roasted pellets are directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder.

[0019] In this embodiment, the copper-nickel slag contains 0.32% copper, 0.39% nickel, and 39.80% iron.

[0020] In this embodiment, the incineration fly ash is waste incineration fly ash with a chlorine content of 26.31%.

[0021] In this embodiment, the moisture content of the green bulbs is 10%.

[0022] In this embodiment, the chlorination separation roasting temperature is 1050℃.

[0023] In this embodiment, the chlorination separation roasting time is 1 hour.

[0024] In this embodiment, the magnetic field strength of the magnetic separation is 1000 Gs.

[0025] The copper-nickel-iron powder obtained in Example 1 has an iron content of 87.38%, a copper content of 0.98%, a nickel content of 4.05%, an iron recovery rate of 68.92%, a copper recovery rate of 82.09%, and a nickel recovery rate of 92.01%.

[0026] Example 2

[0027] A method for preparing copper-nickel-iron powder by co-chlorination separation of copper-nickel slag / incineration fly ash, the method comprising the following steps: finely ground copper-nickel slag and incineration fly ash are mixed at a mass ratio of 1:2.5, and pelletized to obtain green pellets; the green pellets are fed into a chlorination separation reactor for chlorination separation roasting; the roasted pellets are directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder.

[0028] In this embodiment, the copper-nickel slag contains 0.32% copper, 0.39% nickel, and 39.80% iron.

[0029] In this embodiment, the incineration fly ash is hazardous waste incineration fly ash with a chlorine content of 27.81%.

[0030] In this embodiment, the moisture content of the green bulbs is 15%.

[0031] In this embodiment, the chlorination separation roasting temperature is 950°C.

[0032] In this embodiment, the chlorination separation roasting time is 2 hours.

[0033] In this embodiment, the magnetic field strength of the magnetic separation is 1500 Gs.

[0034] The iron content of the copper-nickel-iron powder obtained in Example 2 is 84.38%, the copper content is 0.79%, the nickel content is 3.98%, the iron recovery rate is 70.21%, the copper recovery rate is 85.19%, and the nickel recovery rate is 93.21%.

[0035] Example 3

[0036] A method for preparing copper-nickel-iron powder by co-chlorination separation of copper-nickel slag / incineration fly ash, the method comprising the following steps: finely ground copper-nickel slag and incineration fly ash are mixed at a mass ratio of 1:0.5, and pelletized to obtain green pellets; the green pellets are fed into a chlorination separation reactor for chlorination separation roasting; the roasted pellets are directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder.

[0037] In this embodiment, the copper-nickel slag contains 0.32% copper, 0.39% nickel, and 39.80% iron.

[0038] In this embodiment, the incineration fly ash is waste incineration fly ash with a chlorine content of 26.31%.

[0039] In this embodiment, the moisture content of the green bulbs is 10%.

[0040] In this embodiment, the chlorination separation roasting temperature is 1050℃.

[0041] In this embodiment, the chlorination separation roasting time is 1 hour.

[0042] In this embodiment, the magnetic field strength of the magnetic separation is 1000 Gs.

[0043] The copper-nickel-iron powder obtained in Example 3 has an iron content of 82.38%, a copper content of 0.85%, a nickel content of 3.67%, an iron recovery rate of 65.22%, a copper recovery rate of 80.29%, and a nickel recovery rate of 90.11%.

[0044] Example 4

[0045] A method for preparing copper-nickel-iron powder by co-chlorination separation of copper-nickel slag / incineration fly ash, the method comprising the following steps: finely ground copper-nickel slag and incineration fly ash are mixed at a mass ratio of 1:2, mixed evenly, and pelletized to obtain green pellets; the green pellets are fed into a chlorination separation reactor for chlorination separation roasting; the roasted pellets are directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder.

[0046] In this embodiment, the copper-nickel slag contains 0.59% copper, 0.28% nickel, and 40.68% iron.

[0047] In this embodiment, the incineration fly ash is waste incineration fly ash with a chlorine content of 26.31%.

[0048] In this embodiment, the moisture content of the green bulbs is 10%.

[0049] In this embodiment, the chlorination separation roasting temperature is 1050℃.

[0050] In this embodiment, the chlorination separation roasting time is 1 hour.

[0051] In this embodiment, the magnetic field strength of the magnetic separation is 800 Gs.

[0052] The iron content of the copper-nickel-iron powder obtained in Example 4 is 88.83%, the copper content is 1.06%, the nickel content is 4.99%, the iron recovery rate is 67.25%, the copper recovery rate is 81.33%, and the nickel recovery rate is 88.41%.

[0053] Example 5

[0054] A method for preparing copper-nickel-iron powder by co-chlorination separation of copper-nickel slag / incineration fly ash, the method comprising the following steps: finely ground copper-nickel slag and incineration fly ash are mixed at a mass ratio of 1:2.5, and pelletized to obtain green pellets; the green pellets are fed into a chlorination separation reactor for chlorination separation roasting; the roasted pellets are directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder.

[0055] In this embodiment, the copper-nickel slag contains 0.59% copper, 0.28% nickel, and 40.68% iron.

[0056] In this embodiment, the incineration fly ash is waste incineration fly ash with a chlorine content of 26.31%.

[0057] In this embodiment, the moisture content of the green bulbs is 15%.

[0058] In this embodiment, the chlorination separation roasting temperature is 1200℃.

[0059] In this embodiment, the chlorination separation roasting time is 2 hours.

[0060] In this embodiment, the magnetic field strength of the magnetic separation is 800 Gs.

[0061] The iron content of the copper-nickel-iron powder obtained in Example 5 is 84.32%, the copper content is 0.97%, the nickel content is 4.61%, the iron recovery rate is 65.67%, the copper recovery rate is 80.34%, and the nickel recovery rate is 87.72%.

[0062] Comparative Example 1

[0063] A method for preparing copper-nickel-iron powder by co-chlorination separation of copper-nickel slag / incineration fly ash, the method comprising the following steps: finely ground copper-nickel slag and incineration fly ash are mixed at a mass ratio of 1:2, mixed evenly, and pelletized to obtain green pellets; the green pellets are fed into a chlorination separation reactor for chlorination separation roasting; the roasted pellets are directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder.

[0064] In this embodiment, the copper-nickel slag contains 0.59% copper, 0.28% nickel, and 40.68% iron.

[0065] In this embodiment, the incineration fly ash is waste incineration fly ash with a chlorine content of 26.31%.

[0066] In this embodiment, the moisture content of the green bulbs is 10%.

[0067] In this embodiment, the chlorination separation roasting temperature is 850°C.

[0068] In this embodiment, the chlorination separation roasting time is 1 hour.

[0069] In this embodiment, the magnetic field strength of the magnetic separation is 800 Gs.

[0070] The iron content of the copper-nickel-iron powder obtained in Example 1 is 70.40%, the copper content is 0.63%, the nickel content is 1.32%, the iron recovery rate is 47.12%, the copper recovery rate is 55.36%, and the nickel recovery rate is 58.14%.

[0071] Comparative Example 2

[0072] A method for preparing copper-nickel-iron powder by co-chlorination separation of copper-nickel slag / incineration fly ash, the method comprising the following steps: finely ground copper-nickel slag and incineration fly ash are mixed at a mass ratio of 1:0.4, and pelletized to obtain green pellets; the green pellets are fed into a chlorination separation reactor for chlorination separation roasting; the roasted pellets are directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder.

[0073] In this embodiment, the copper-nickel slag contains 0.32% copper, 0.39% nickel, and 39.80% iron.

[0074] In this embodiment, the incineration fly ash is waste incineration fly ash with a chlorine content of 26.31%.

[0075] In this embodiment, the moisture content of the green bulbs is 10%.

[0076] In this embodiment, the chlorination separation roasting temperature is 1050℃.

[0077] In this embodiment, the chlorination separation roasting time is 1 hour.

[0078] In this embodiment, the magnetic field strength of the magnetic separation is 1000 Gs.

[0079] The iron content of the copper-nickel-iron powder obtained in Example 2 is 62.87%, the copper content is 0.48%, the nickel content is 1.29%, the iron recovery rate is 38.26%, the copper recovery rate is 50.11%, and the nickel recovery rate is 52.43%.

[0080] Comparative Example 3

[0081] A method for preparing copper-nickel-iron powder by co-chlorination separation of copper-nickel slag / incineration fly ash, the method comprising the following steps: finely ground copper-nickel slag and incineration fly ash are mixed at a mass ratio of 1:1 and mixed evenly to form green pellets; the green pellets are fed into a chlorination separation reactor for chlorination separation roasting; the roasted pellets are directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder.

[0082] In this embodiment, the copper-nickel slag contains 0.32% copper, 0.39% nickel, and 39.80% iron.

[0083] In this embodiment, the incineration fly ash is waste incineration fly ash with a chlorine content of 26.31%.

[0084] In this embodiment, the moisture content of the green bulbs is 10%.

[0085] In this embodiment, the chlorination separation roasting temperature is 1050℃.

[0086] In this embodiment, the chlorination separation roasting time is 0.4 h.

[0087] In this embodiment, the magnetic field strength of the magnetic separation is 1000 Gs.

[0088] The copper-nickel-iron powder obtained in Example 3 has an iron content of 76.13%, a copper content of 0.64%, a nickel content of 2.10%, an iron recovery rate of 50.13%, a copper recovery rate of 62.30%, and a nickel recovery rate of 65.51%.

[0089] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects. The scope of the invention is defined by the appended claims rather than the foregoing description, and all changes falling within the meaning and scope of the equivalents of the claims are intended to be included within the present invention.

[0090] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other implementation schemes that can be understood by those skilled in the art.

Claims

1. A method for preparing copper-nickel-iron powder containing copper-nickel slag / incineration fly ash co-chlorination separation, characterized in that: The method includes the following steps: finely ground copper-nickel slag and incineration fly ash are mixed at a mass ratio of 1:(0.8~1.5) and pelletized to obtain green pellets; the moisture content of the green pellets is 10%~15%; the green pellets are fed into a chlorination separation reactor for chlorination separation roasting; wherein the incineration fly ash is used as both a chlorinating agent and a reducing agent, and no other reducing agent is added; the roasted pellets are directly water-quenched, finely ground, and magnetically separated to obtain copper-nickel-iron powder.

2. The method for preparing copper-nickel-iron powder by co-chlorination and segregation of copper-nickel slag / incineration fly ash according to claim 1, characterized in that: The copper-nickel slag is finely ground to less than 0.074 mm.

3. The method for preparing copper-nickel-iron powder by co-chlorination and segregation of copper-nickel slag / incineration fly ash according to claim 1, characterized in that: The chlorination and decomposition calcination temperature is 900~1200 o C.

4. The method for preparing copper-nickel-iron powder by co-chlorination and segregation of copper-nickel slag / incineration fly ash according to claim 1, characterized in that: The chlorination separation roasting time is 0.5~2h.

5. The method for preparing copper-nickel-iron powder by co-chlorination and segregation of copper-nickel slag / incineration fly ash according to claim 1, characterized in that: The calcined balls are finely ground to less than 0.074 mm.

6. The method for preparing copper-nickel-iron powder by co-chlorination and segregation of copper-nickel slag / incineration fly ash according to claim 1, characterized in that: The magnetic field strength of the magnetic separation is 800 Gs to 1500 Gs.

7. The method for preparing copper-nickel-iron powder by co-chlorination and segregation of copper-nickel slag / incineration fly ash according to claim 1, characterized in that: The incineration fly ash is one or more of the following: waste incineration fly ash or hazardous waste incineration fly ash.