A smelting furnace copper jacket structure design method based on thermal expansion compensation

Abstract

The present application relates to smelting furnace equipment technical field, specifically relates to a kind of based on thermal expansion compensation's smelting furnace copper jacket structure design method, comprising the following steps: (1) thermal expansion characteristic data acquisition: (2) expansion difference calculation: based on the data of step (1) acquisition, in combination with the rated working temperature when smelting furnace normal production, the theoretical thermal expansion of refractory brick and copper jacket in length direction is calculated respectively, and then the expansion difference ΔL of refractory brick and copper jacket is obtained;(3) thermal expansion compensation model is established;(4) copper jacket structure design: based on thermal expansion compensation model, traditional cuboid copper jacket is optimized as Z-shaped structure, the bending angle α of Z-shaped structure, occlusion length L1, body length L2 are designed;(5) structure rationality verification (6) working condition adaptation adjustment.The present application utilizes the elastic deformation characteristics of Z-shaped structure to accurately compensate the expansion difference of refractory brick and copper jacket due to the difference of thermal expansion coefficient, and completely eliminates through slit.

Description

Technical Field

[0001] This invention relates to the field of smelting furnace equipment technology, and specifically to a design method for a copper water jacket structure of a smelting furnace based on thermal expansion compensation. Background Technology

[0002] As a core piece of equipment in the non-ferrous metal smelting industry, the structural stability and safety of the hearth section of the smelting furnace directly determine the continuity of production, product quality, and operating costs. Currently, the industry commonly adopts a hearth structure constructed with a mixture of refractory bricks and copper water jackets. This involves laying several layers of refractory bricks, followed by a full layer of copper water jacket. The copper water jacket is assembled along the length of the furnace using a planar butt joint method. By leveraging the high-temperature resistance of the refractory bricks and the efficient cooling performance of the copper water jacket, the stable operation of the hearth under high-temperature conditions is ensured.

[0003] However, in actual production, this traditional structure revealed significant technical defects: the thermal expansion coefficients of the refractory bricks and the copper water jacket are fundamentally different. In the high-temperature operating environment of the smelting furnace (800-1200℃), the thermal expansion of the refractory bricks is far greater than that of the copper water jacket. This uneven expansion causes the refractory bricks to exert a lateral thrust on the copper water jacket during expansion, leading to displacement of the copper water jacket and resulting in a through-gap at the joint of adjacent copper water jacket sections. This through-gap not only prevents the cooling effect of the copper water jacket from covering the gap area, causing abnormal local temperature increases and accelerating the aging of the refractory bricks and the wear of the copper water jacket, but also provides a leakage channel for the high-temperature melt in the smelting furnace. Once a melt leak occurs, it will cause a serious safety accident, threatening personnel lives and equipment safety.

[0004] To address these issues, existing technologies often employ passive improvements such as increasing the density of refractory brickwork, increasing the thickness of the copper water jacket, and optimizing the masonry process. However, these solutions do not fundamentally resolve the mismatch in expansion caused by differences in thermal expansion coefficients. They can only alleviate the rate of through-crack formation in the short term and cannot completely eliminate the risk of molten metal leakage. Furthermore, frequent through-crack repairs and equipment maintenance not only increase labor and material costs but also lead to frequent furnace shutdowns, severely impacting production continuity, reducing capacity efficiency, and shortening the overall lifespan of the furnace. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention provides a design method for a copper water jacket structure of a smelting furnace based on thermal expansion compensation.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A design method for a copper water jacket structure of a smelting furnace based on thermal expansion compensation includes the following steps:

[0008] (1) Data acquisition of thermal expansion characteristics: obtain the theoretical linear expansion coefficient of refractory bricks and copper water jackets for smelting furnace hearth, as well as the temperature distribution data and thermal stress change data of refractory bricks and copper water jackets in the actual working temperature range;

[0009] (2) Calculation of expansion difference: Based on the data collected in step (1) and the rated working temperature of the smelting furnace during normal production, the theoretical thermal expansion of the refractory brick and the copper water jacket in the length direction is calculated respectively, and the expansion difference ΔL between the refractory brick and the copper water jacket is obtained.

[0010] (3) Establishment of thermal expansion compensation model: Taking the expansion difference ΔL as the core compensation index, establish a thermal expansion compensation mathematical model that includes structural form, interlocking angle and size parameters;

[0011] (4) Copper water jacket structure design: Based on the thermal expansion compensation model, the traditional rectangular copper water jacket is optimized into a Z-shaped structure. The bending angle α, interlocking length L1, and body length L2 of the Z-shaped structure are designed so that adjacent copper water jackets form a staggered interlocking structure after assembly. The elastic deformation characteristics of the Z-shaped structure are used to compensate for the expansion difference ΔL.

[0012] (5) Verification of structural rationality: Through high temperature simulation experiments, the expansion and deformation of the Z-shaped copper water jacket at the rated working temperature, the cooling effect and the working state with the refractory bricks are tested to verify whether it meets the requirements of seamless and leak-proof.

[0013] (6) Working condition adaptation adjustment: Based on the actual production conditions of the smelting furnace, the size parameters of the Z-shaped copper water jacket are finely adjusted to ensure structural adaptability and long-term stability.

[0014] Furthermore, in step (1), the actual working temperature range is 800-1200℃, and the temperature distribution data is collected by the temperature sensor built into the furnace cylinder. The collection frequency is 1 time / hour, and the collection cycle is no less than 72 hours.

[0015] Furthermore, in step (2), the formula for calculating the expansion difference ΔL is ΔL = L0 × (α 砖 ×T-α 铜 ×T), where L0 is the original length of the copper water jacket, α 砖 Let α be the theoretical coefficient of linear expansion of the refractory brick. 铜 Here, is the theoretical coefficient of linear expansion of the copper water jacket, and T is the difference between the rated operating temperature and the ambient temperature.

[0016] Furthermore, in step (4), the bending angle α of the Z-shaped structure is 30°-60°, the interlocking length L1 is 1.2-1.5 times the expansion difference ΔL, and the body length L2 is set in segments according to the furnace hearth construction length, with a single segment length of 1.5-2.5m.

[0017] Furthermore, in step (5), the ambient temperature of the high-temperature simulation experiment is simulated to the rated working temperature, the heat preservation time is not less than 48 hours, and the gap width at the connection of adjacent copper water jackets is detected by ultrasonic testing, with the gap width ≤ 0.1 mm.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] This invention accurately collects thermal expansion characteristic data of refractory bricks and copper water jackets, calculates the difference in their expansion amounts, establishes a targeted thermal expansion compensation model, designs a Z-shaped copper water jacket structure, and optimizes key parameters. Verified through high-temperature simulation experiments and adapted to actual working conditions, this invention not only utilizes the elastic deformation characteristics of the Z-shaped structure to accurately compensate for the expansion difference between refractory bricks and copper water jackets caused by the difference in their thermal expansion coefficients, completely eliminating through-gaps and blocking melt leakage paths at the source, significantly improving the intrinsic safety level of the smelting furnace, but also ensures stable cooling effect of the copper water jacket, effectively extending the furnace hearth maintenance cycle, reducing maintenance frequency and downtime losses, and lowering production costs. Furthermore, this design method has a standardized process, controllable parameters, and adapts to the needs of smelting furnaces under different production conditions, possessing good practicality, reliability, and industrialization potential. Attached Figure Description

[0020] The embodiments of the present invention will be further described below with reference to the accompanying drawings, wherein:

[0021] Figure 1 A process flow diagram of the present invention is shown. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] Reference Appendix Figure 1 A design method for a copper water jacket structure of a smelting furnace based on thermal expansion compensation includes the following steps:

[0024] Step 1: Data Acquisition of Thermal Expansion Characteristics

[0025] First, determine the material specifications of the refractory bricks and copper water jacket used in the furnace hearth of the smelting furnace. Then, consult the material property handbook to find the theoretical coefficients of linear expansion (α) for both. 砖 α 铜 Subsequently, under normal production conditions of the smelting furnace, temperature sensors were installed in different areas of the furnace hearth to collect temperature distribution data within the operating temperature range of 800-1200℃. Simultaneously, thermal stress change data for both was acquired through stress monitoring equipment. The temperature acquisition frequency was once per hour, with a collection cycle of no less than 72 hours, ensuring that the data accurately reflected the temperature fluctuation patterns under actual operating conditions.

[0026] Step 2: Calculation of the difference in expansion amount

[0027] Based on the data collected in step 1, and combined with the rated operating temperature T0 of the smelting furnace (usually 1000℃), calculate the difference between the ambient temperature (default 25℃) and the rated operating temperature, T = T0 - 25℃; then, according to the formula for calculating thermal expansion: ΔL 材 =L0×α 材 ×T (where L0 is the original length of the material), calculate the theoretical thermal expansion of the refractory brick and the copper water jacket along their length respectively. The difference between the two is the expansion difference ΔL = ΔL 砖 -ΔL 铜 This difference is the core basis for subsequent structural optimization and directly determines the design parameters of the compensation structure.

[0028] Step 3: Establishing a thermal expansion compensation model

[0029] Using the expansion difference ΔL as the core compensation index, and comprehensively considering the cooling intensity requirements of the copper water jacket (ensuring the copper water jacket wall temperature ≤300℃) and the space constraints of the furnace hearth construction (width and height allowances ≤50mm), a mathematical model for thermal expansion compensation is established. The model includes key parameters such as structural form (Z-shaped), bending angle α, engagement length L1, and body length L2. Iterative calculations are performed using numerical simulation software (such as ANSYS) to determine the value range of each parameter.

[0030] Step 4: Design of copper water jacket structure

[0031] Based on a thermal expansion compensation model, a Z-shaped copper water jacket structure is designed, abandoning the traditional cuboid structure: the bending angle α is set at 30°-60° (to ensure sufficient elastic deformation capacity of the structure), the interlocking length L1 is 1.2-1.5 times the expansion difference ΔL (to ensure tight interlocking during expansion), and the body length L2 is set in segments according to the length of the furnace hearth lining, with a single segment length of 1.5-2.5m (for easy processing and installation). After adjacent Z-shaped copper water jackets are assembled, their bending parts interlock to form a staggered structure. When the refractory bricks expand and cause the copper water jacket to shift, the Z-shaped structure can absorb the expansion difference ΔL through its own elastic deformation, avoiding the formation of continuous seams.

[0032] Step 5: Verification of structural rationality

[0033] A high-temperature simulation experimental platform was constructed. The optimized Z-shaped copper water jacket and refractory bricks were assembled according to the actual masonry method to simulate a rated working temperature of 1000℃ for 48 hours. During the experiment, the gap width at the connection between adjacent copper water jackets was monitored in real time using ultrasonic testing equipment, requiring a gap width ≤ 0.1mm; simultaneously, the cooling effect of the copper water jacket was monitored using temperature measuring equipment to ensure that the wall temperature ≤ 300℃. If the requirements were not met, the process returned to step 4 to adjust the structural parameters until the verification was successful.

[0034] Step 6: Working Condition Adaptation and Adjustment

[0035] Based on the actual temperature fluctuation range (typically ±50℃) and changes in copper concentrate grade during smelting furnace production, the bending angle α (adjusted by ±5°) and engagement length L1 (adjusted by ±10mm) of the Z-shaped copper water jacket are finely adjusted. For example, when the furnace temperature rises due to an increase in copper concentrate grade, the engagement length L1 is appropriately increased to ensure that the thermal expansion difference can still be effectively compensated within the temperature fluctuation range, thus guaranteeing the long-term stability and adaptability of the structure.

[0036] Example 1

[0037] A pyrometallurgical plant's smelting furnace has a hearth lining length of 10m. The theoretical linear expansion coefficient α of the refractory bricks used is... 砖 =5.2×10 -6 / ℃, the copper water jacket is made of pure copper, and the theoretical coefficient of linear expansion α 铜 =16.5×10 -6 / ℃, rated operating temperature T0=1000℃.

[0038] The method of this invention is used for the design of copper water jacket structures:

[0039] (1) Collection of thermal expansion characteristic parameters: Temperature distribution data were collected over 72 hours. The average working temperature was 980℃. Thermal stress monitoring showed that there was no obvious stress concentration phenomenon.

[0040] (2) Calculation of expansion difference: T=980-25=955℃, original length of copper water jacket L0=2m,

[0041] ΔL 砖 =2×5.2×10 -6 ×955≈0.010m, ΔL 铜 =2×16.5×10 -6 ×955≈0.032m,

[0042] The difference in expansion ΔL = 0.032 - 0.010 = 0.022m = 22mm.

[0043] (3) Establishment of thermal expansion compensation model: The cooling intensity requirement is set to the copper water jacket wall temperature ≤300℃, the masonry space reserve is ≤50mm, the bending angle α=45°, the interlocking length L1=22×1.3=28.6mm≈29mm, and the body length L2=2m.

[0044] (4) Copper water jacket structure design: The Z-shaped copper water jacket is processed with a bending angle of 45°, an interlocking length of 29mm, a body length of 2m, and a total of 5 sections spliced ​​together to cover the 10m furnace hearth length.

[0045] (5) Verification of structural rationality: The high temperature simulation experiment was kept at a temperature of 48 hours. The ultrasonic test showed that the gap width was ≤0.08mm and the copper water jacket wall temperature was 280℃, which met the design requirements.

[0046] (6) Working condition adaptation adjustment: Considering the furnace temperature fluctuation of ±50℃, the engagement length is adjusted to 30mm and the bending angle is kept at 45° to complete the final design.

[0047] After the Z-shaped copper water jacket was applied to the smelting furnace, no through gaps were generated in the furnace hearth after one year of operation, the risk of melt leakage was completely eliminated, and the maintenance cycle is expected to be extended to 6 years.

[0048] This invention accurately collects thermal expansion characteristic data of refractory bricks and copper water jackets, calculates the difference in their expansion amounts, establishes a targeted thermal expansion compensation model, designs a Z-shaped copper water jacket structure, and optimizes key parameters. Verified through high-temperature simulation experiments and adapted to actual working conditions, this invention not only utilizes the elastic deformation characteristics of the Z-shaped structure to accurately compensate for the expansion difference between refractory bricks and copper water jackets caused by the difference in their thermal expansion coefficients, completely eliminating through-gaps and blocking melt leakage paths at the source, significantly improving the intrinsic safety level of the smelting furnace, but also ensures stable cooling effect of the copper water jacket, effectively extending the furnace hearth maintenance cycle, reducing maintenance frequency and downtime losses, and lowering production costs. Furthermore, this design method has a standardized process, controllable parameters, and adapts to the needs of smelting furnaces under different production conditions, possessing good practicality, reliability, and industrialization potential.

[0049] The foregoing descriptions have outlined some exemplary embodiments of the present invention. It is understood that these embodiments are merely illustrative and do not constitute a limitation on the scope of protection of the present invention. Features in these embodiments can be rearranged in suitable ways, and the resulting solutions remain within the scope of protection claimed by the present invention. All other embodiments obtained by those skilled in the art based on the foregoing embodiments without inventive effort, i.e., all modifications, equivalent substitutions, and improvements made within the spirit and principles of this application, fall within the scope of protection claimed by the present invention.

Claims

1. A design method for a copper water jacket structure of a smelting furnace based on thermal expansion compensation, characterized in that, Includes the following steps: Thermal expansion characteristic data acquisition: Obtain the theoretical linear expansion coefficient of refractory bricks and copper water jackets for smelting furnace hearths, as well as the temperature distribution data and thermal stress change data of refractory bricks and copper water jackets in the actual working temperature range; Expansion difference calculation: Based on the data collected in step (1) and the rated working temperature of the smelting furnace during normal production, calculate the theoretical thermal expansion of the refractory brick and the copper water jacket in the length direction, and then obtain the expansion difference ΔL between the refractory brick and the copper water jacket. Thermal expansion compensation model establishment: Taking the expansion difference ΔL as the core compensation index, a thermal expansion compensation mathematical model including structural form, interlocking angle, and dimensional parameters is established. Copper water jacket structure design: Based on the thermal expansion compensation model, the traditional rectangular copper water jacket is optimized into a Z-shaped structure. The bending angle α, interlocking length L1, and body length L2 of the Z-shaped structure are designed so that adjacent copper water jackets form a staggered interlocking structure after assembly. The elastic deformation characteristics of the Z-shaped structure are used to compensate for the expansion difference ΔL. Structural rationality verification: Through high-temperature simulation experiments, the expansion and deformation of the Z-shaped copper water jacket at the rated working temperature, the cooling effect, and the working state in synergy with the refractory bricks were tested to verify whether it meets the requirements of seamless and leak-proof. Operating condition adaptation adjustment: Based on the actual production conditions of the smelting furnace, the dimensional parameters of the Z-shaped copper water jacket are finely adjusted to ensure structural adaptability and long-term stability.

2. The design method for the copper water jacket structure of a smelting furnace based on thermal expansion compensation according to claim 1, characterized in that, In step (1), the actual working temperature range is 800-1200℃. Temperature distribution data is collected by the temperature sensor built into the furnace cylinder. The collection frequency is once per hour, and the collection cycle is no less than 72 hours.

3. The design method for the copper water jacket structure of a smelting furnace based on thermal expansion compensation according to claim 1, characterized in that, In step (2), the formula for calculating the expansion difference ΔL is ΔL = L0 × (α) 砖 ×T-α 铜 ×T), where L0 is the original length of the copper water jacket, α 砖 Let α be the theoretical coefficient of linear expansion of the refractory brick. 铜 Here, is the theoretical coefficient of linear expansion of the copper water jacket, and T is the difference between the rated operating temperature and the ambient temperature.

4. The design method for the copper water jacket structure of a smelting furnace based on thermal expansion compensation according to claim 1, characterized in that, In step (4), the bending angle α of the Z-shaped structure is 30°-60°, the interlocking length L1 is 1.2-1.5 times the expansion difference ΔL, and the body length L2 is set in sections according to the furnace hearth construction length, with a single section length of 1.5-2.5m.

5. The design method for the copper water jacket structure of a smelting furnace based on thermal expansion compensation according to claim 1, characterized in that, In step (5), the ambient temperature of the high temperature simulation experiment is the same as the rated working temperature, and the heat preservation time is not less than 48 hours. The gap width at the connection of adjacent copper water jackets is detected by ultrasonic testing, and the gap width is ≤0.1mm.

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