A method for forming copper-containing sludge

Abstract

The present application relates to solid waste resource processing technical field, specifically to a kind of method for forming copper-containing sludge, comprising (1) copper-containing sludge is dried to moisture content 15~30%, waste resin powder particle size is 100 mesh below 90% or more than account ratio;(2) according to weight ratio, copper-containing sludge 100 parts, waste resin powder 15~25 parts, flux 3~5 parts;(3) in strong mixer, material is mixed uniformly, stirring time is 20~30min;(4) mixed material is poured into heating tank, there is gas collection device on heating tank, heating mixed material center temperature is 125~225℃, heat preservation 10~30min;(5) forming under 15~25MPa pressure, maintaining time 1~3min, strength meets the requirement, copper-containing sludge briquette is obtained.The forming method of the present application, waste resin powder is treated simultaneously, copper-containing sludge briquette obtained has high strength, good thermal stability, does not need to add binder, reduces energy consumption, also reduces environmental pollution.

Description

Technical Field

[0001] This invention relates to the field of solid waste resource utilization technology, specifically to a method for forming copper-containing sludge. Background Technology

[0002] Sludge, a byproduct of wastewater treatment, is a viscous substance between liquid and solid, and is generally difficult to treat harmlessly at low cost, especially copper sludge. Copper sludge mainly originates from wastewater treatment processes in industries such as metal surface treatment, heat treatment, electronic component manufacturing, electroplating, and basic chemical raw material manufacturing. It contains multiple metals such as Cu, Fe, Ni, and Zn, and has complex properties, making it a recognized hazardous waste both domestically and internationally. Recovering the high levels of copper, nickel, chromium, and iron from copper-containing sludge can not only alleviate environmental pollution and achieve cleaner production, but also yield significant ecological and economic benefits. Due to the large volume of sludge produced, pyrometallurgical treatment is the most effective way to achieve harmlessness, volume reduction, and resource recovery of this type of sludge. However, because copper-containing sludge has a high water content and fine particle size, drying during pyrometallurgical treatment and the subsequent molding process require the use of binders, increasing treatment costs and reducing economic efficiency.

[0003] With the rapid development of electronic technology, the number of waste circuit boards has surged. While valuable metals can be recovered through crushing and sorting, a large amount of waste resin powder is generated simultaneously. Waste resin powder typically accounts for 76% to 94% of waste circuit boards, and its main components include resin, glass fiber, and brominated flame retardants (polybrominated diphenyl ethers), classifying it as organic resin waste, which is a toxic and hazardous waste. The large quantity of waste resin powder generated currently involves methods such as stockpiling, landfilling, incineration, or even indiscriminate dumping. This not only occupies land but also easily generates dust, causing secondary environmental pollution to water, air, and soil. Therefore, it is necessary to strengthen the comprehensive utilization of waste resin powder to prevent environmental pollution. Summary of the Invention

[0004] The purpose of this invention is to provide a molding method for copper-containing sludge, so as to reduce the molding cost in the pyrometallurgical treatment of copper-containing sludge, while realizing the recycling of waste resin powder and reducing environmental pollution.

[0005] To address the above problems, the present invention provides a method for forming copper-containing sludge, comprising the following steps:

[0006] (1) Raw material pretreatment

[0007] The copper-containing sludge is dried to a moisture content of 15-30%, and the waste resin powder has a particle size of more than 90% passing through a 100-mesh sieve.

[0008] (2) Ingredients

[0009] Weigh the various raw material components according to the weight ratio, and the specific ratio is: 100 parts copper-containing sludge, 15-25 parts waste resin powder, and 3-5 parts flux.

[0010] (3) Mix well

[0011] Stir in a high-powered mixer to ensure the materials are mixed evenly for 20–30 minutes.

[0012] (4) Heating

[0013] Pour the mixture into the heating tank, which has a gas collection device on top. Heat the center temperature of the mixture to 125-225℃ and keep it at that temperature for 10-30 minutes.

[0014] (5) Molding

[0015] Molding is carried out under a pressure of 15-25 MPa for 1-3 minutes. After the strength meets the requirements, copper-containing sludge blocks are obtained. The moisture content is controlled at 10-15%. The cold compressive strength is higher than 1000 N / piece, and the drop strength is greater than 4 times / piece.

[0016] The copper-containing sludge molding method provided by this invention overcomes the bias of simply treating waste resin powder as toxic hazardous waste. By utilizing the glass fiber, thermosetting epoxy resin, and various additives contained within the resin, it develops thermoplasticity during heating, thus replacing the binder in the copper-containing sludge molding process. Simultaneously, the heat generated by the combustion of organic matter in the waste resin powder during pyrometallurgical treatment, and the inorganic matter in the waste resin powder acting as a flux, reduce the cost of copper-containing sludge molding while simultaneously treating the waste resin powder, providing heat and flux for pyrometallurgical processes, and promoting green circular economy development through waste-to-waste treatment. The copper-containing sludge agglomerates obtained by this molding method have high strength, with a cold compressive strength exceeding 1000 N / agglomerate and a drop strength greater than 4 times / agglomerate; good thermal stability, allowing direct addition to an oxygen-enriched top-blown melting furnace for processing. The calorific value of the copper-containing sludge agglomerates can reach 3-5 MJ / kg, significantly reducing energy consumption during the melting process. Furthermore, the elimination of the need for binders further reduces energy consumption. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention.

[0018] Figure 1 This is a process flow diagram of the copper-containing sludge molding method in this embodiment. Detailed Implementation

[0019] The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the invention. Where specific techniques or conditions are not specified in the embodiments, they should be performed in accordance with the techniques or conditions described in the literature in the field, or in accordance with the product manual.

[0020] In the description of this invention, unless otherwise stated, the terms "upper" and "lower" indicate the orientation or state relationship based on the orientation or state relationship shown in the drawings, and are only for the convenience of describing the invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention.

[0021] In the following embodiments, all instruments and equipment used, unless otherwise specified, are conventional products that can be purchased through legitimate channels. Unless otherwise stated, all methods described are conventional methods, and all raw materials are available from publicly available commercial sources.

[0022] Example 1

[0023] like Figure 1 As shown in the figure, this embodiment provides a method for forming copper-containing sludge, which mainly includes the following steps:

[0024] (1) Raw material pretreatment

[0025] The copper-containing sludge was dried to a moisture content of 25%, and the waste resin powder had a particle size of 95% passing through a 100-mesh sieve.

[0026] (2) Ingredients

[0027] Weigh the various raw material components according to the weight ratio, and the specific ratio is: 100 parts copper-containing sludge, 20 parts waste resin powder, and 4 parts flux.

[0028] (3) Mix well

[0029] Stir in a high-powered mixer to ensure the materials are mixed evenly for 25 minutes.

[0030] (4) Heating

[0031] Pour the mixture into the heating tank, which has a gas collection device on top. Heat the center temperature of the mixture to 205°C and keep it at that temperature for 15 minutes.

[0032] (5) Molding

[0033] Molding is carried out under a pressure of 20 MPa for 2 minutes. After the strength meets the requirements, copper-containing sludge briquettes are obtained. The moisture content is controlled at 12%. The cold compressive strength is higher than 1250 N / piece, and the drop strength is greater than 5 times / piece. They can be directly added to the oxygen-enriched top-blown melting furnace for processing. The calorific value of the briquettes made from copper-containing sludge can reach more than 3 MJ / kg, which can significantly reduce the energy consumption in the melting process.

[0034] Table 1. Main chemical components (%) of copper-containing sludge

[0035] Cu Ni Cr Zn Fe Ca Mg 12.12 7.45 13.06 3.82 16.36 3.68 1.58

[0036] The copper-containing sludge has high levels of Cu, Ni, and Cr, mainly in the form of hydroxides, and also contains a small amount of basic sulfates. The Ca and Mg in the raw material are mainly introduced by lime from the electroplating wastewater sedimentation process, existing in the form of calcium sulfate and magnesium hydroxide.

[0037] Table 2 Physicochemical characteristics of waste resin powder

[0038] Calorific value (MJ / Kg) Moisture (%) Ash content (%) Volatile matter (%) Fixed carbon (%) 22.19 2.58 5.25 65.35 29.40

[0039] Example 2

[0040] The molding method in Example 2 is basically the same as that in Example 1, with the main difference being the selection of parameters. This example provides a method for molding copper-containing sludge, which mainly includes the following steps:

[0041] (1) Raw material pretreatment

[0042] The copper-containing sludge was dried to a moisture content of 30%, and the waste resin powder had a particle size of 90% passing through a 100-mesh sieve.

[0043] (2) Ingredients

[0044] Weigh all the raw materials according to the following weight ratio: 100 parts copper-containing sludge, 25 parts waste resin powder, and 3 parts flux.

[0045] (3) Mix well

[0046] Stir in a high-powered mixer to ensure the materials are mixed evenly for 20 minutes.

[0047] (4) Heating

[0048] Pour the mixture into the heating tank, which has a gas collection device on top. Heat the center temperature of the mixture to 125°C and keep it at that temperature for 30 minutes.

[0049] (5) Molding

[0050] Molding is carried out under a pressure of 15MPa for 3 minutes. After the strength meets the requirements, copper-containing sludge blocks are obtained. The moisture content is controlled at 15%. The cold compressive strength is higher than 1000N / piece, and the drop strength is greater than 4 times / piece.

[0051] Table 3. Main chemical components (%) of copper-containing sludge

[0052] Cu Ni Cr Zn Fe Ca Mg 12.73 7.82 13.71 4.01 17.18 3.86 1.66

[0053] The copper-containing sludge has high levels of Cu, Ni, and Cr, mainly in the form of hydroxides, and also contains a small amount of basic sulfates. The Ca and Mg in the raw material are mainly introduced by lime from the electroplating wastewater sedimentation process, existing in the form of calcium sulfate and magnesium hydroxide.

[0054] Table 4 Physicochemical characteristics of waste resin powder

[0055] Calorific value (MJ / Kg) Moisture (%) Ash content (%) Volatile matter (%) Fixed carbon (%) 20.45 4.23 6.85 69.45 23.7

[0056] Example 3

[0057] The molding method in Example 3 is basically the same as that in Example 1, with the main difference being the selection of parameters. This example provides a method for molding copper-containing sludge, which mainly includes the following steps:

[0058] (1) Raw material pretreatment

[0059] The copper-containing sludge was dried to a moisture content of 20%, and the waste resin powder had a particle size of 93% passing through a 100-mesh sieve.

[0060] (2) Ingredients

[0061] Weigh the various raw material components according to the weight ratio, and the specific ratio is: 100 parts copper-containing sludge, 15 parts waste resin powder, and 5 parts flux.

[0062] (3) Mix well

[0063] Stir in a high-powered mixer to ensure the materials are mixed evenly for 30 minutes.

[0064] (4) Heating

[0065] Pour the mixture into the heating tank, which has a gas collection device on top. Heat the center temperature of the mixture to 185°C and keep it at that temperature for 20 minutes.

[0066] (5) Molding

[0067] Molding is carried out under a pressure of 25MPa for 1 minute. After the strength meets the requirements, copper-containing sludge blocks are obtained. The moisture content is controlled at 10%. The cold compressive strength is higher than 1100N / piece, and the drop strength is greater than 5 times / piece.

[0068] Table 5. Main chemical components (%) of copper-containing sludge

[0069] Cu Ni Cr Zn Fe Ca Mg 11.51 7.08 12.41 3.63 15.54 3.50 1.50

[0070] The copper-containing sludge has high levels of Cu, Ni, and Cr, mainly in the form of hydroxides, and also contains a small amount of basic sulfates. The Ca and Mg in the raw material are mainly introduced by lime from the electroplating wastewater sedimentation process, existing in the form of calcium sulfate and magnesium hydroxide.

[0071] Table 6 Physicochemical characteristics of waste resin powder

[0072] Calorific value (MJ / Kg) Moisture (%) Ash content (%) Volatile matter (%) Fixed carbon (%) 24.73 2.85 3.76 70.11 26.13

[0073] As for the selection of other reaction parameters, those skilled in the art can determine them based on common knowledge, such as the specific determination of parameters like the drying temperature of copper-containing sludge and the stirring speed of a high-powered mixer. In addition, percentages not explicitly stated in this application are usually mass percentages and will not be elaborated further.

[0074] The above descriptions are merely embodiments of the present invention. Commonly known structures, properties, and reactant ratios are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. For example, simply adjusting the parameter selection within or near a specified parameter range should also be considered within the scope of protection of the present invention, and these will not affect the effectiveness of the invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for forming copper-containing sludge, characterized in that... The steps include the following: (1) Raw material pretreatment: dry copper-containing sludge to a moisture content of 15-30% and waste resin powder with a particle size of more than 90% passing through a 100-mesh sieve. (2) Ingredients: Weigh all raw materials according to the weight ratio. The specific ratio is: 100 parts copper-containing sludge, 15-25 parts waste resin powder, and 3-5 parts flux. (3) Mix well. Stir in a high-powered mixer to make the materials evenly mixed. The stirring time is 20 to 30 minutes. (4) Heating: Pour the mixture into a heating tank. There is a gas collection device above the heating tank. Heat the center temperature of the mixture to 125~225℃ and keep it warm for 10~30 minutes. The waste resin powder generates thermoplasticity during the heating process and is used to replace the binder in the molding process of copper-containing sludge. At the same time, the inorganic matter in the waste resin powder is used as a flux. (5) Molding: Molding is carried out under a pressure of 15-25 MPa for 1-3 minutes. After the strength meets the requirements, copper-containing sludge blocks are obtained. The moisture content is controlled at 10-15%, the cold compressive strength is higher than 1000 N / piece, and the drop strength is greater than 4 times / piece.

2. The method for forming copper-containing sludge according to claim 1, characterized in that: In step (1), the copper-containing sludge is dried to a moisture content of 20%, and the waste resin powder has a particle size of 95% below a 100-mesh sieve.

3. The method for forming copper-containing sludge according to claim 1, characterized in that: The proportions in step (2) are: 100 parts copper-containing sludge, 20 parts waste resin powder, and 4 parts flux.

4. The method for forming copper-containing sludge according to claim 1, characterized in that: In step (4), the center temperature of the mixture is heated to 205°C and kept warm for 15 minutes.

5. The method for forming copper-containing sludge according to claim 1, characterized in that: In step (5), the copper-containing sludge blocks are formed under a pressure of 20 MPa for 2 minutes. After the strength meets the requirements, the moisture content is controlled at 12%, the cold compressive strength is higher than 1250 N / piece, and the drop strength is greater than 5 times / piece.

Images