Electrode paste for smelting metal silicon and manufacturing method thereof

Abstract

The invention discloses an electrode paste for smelting metal silicon and a manufacturing method of the electrode paste, and relates to the field of metallurgical engineering. The electrode paste is manufactured by taking a carbon raw material as an aggregate and an organic compound as a binder through the processes of crushing, screening, grinding, batching, binder melting, dry mixing, wet mixing, paste pulling forming and the like, and comprises the following components in percentage by weight: 78-80% of the carbon aggregate and 20-22% of the organic binder, the carbon aggregate comprises 10% of electrically calcined anthracite, 10%-15% of calcined petroleum coke, 20%-25% of pitch coke, 30% of anode scrap, 17%-20% of artificial graphite and 5%-8% of natural amorphous graphite; the organic binder comprises 90% of medium-temperature pitch and 10% of anthracene oil. After the electrode paste is used for the metal silicon submerged arc furnace, the problems of hard breakage, soft breakage, paste flowing and the like of a self-baking electrode caused by the quality of the electrode paste can be effectively avoided, the smelting process requirements are completely met, and the electrode paste is low in raw material cost, high in process control precision, high in strength, low in resistivity and excellent in thermal shock resistance.

Description

Technical Field

[0001] This invention relates to the field of non-metallic materials in metallurgical engineering, and more particularly to the field of carbon materials. Specifically, it relates to an electrode paste for smelting metallic silicon and its manufacturing method. Background Technology

[0002] Submerged arc furnaces, also known as electric resistance furnaces or electric arc furnaces, are mainly used in the metallurgical and chemical industries to smelt and produce ferroalloys such as metallic silicon, ferrosilicon, ferromanganese, ferrochrome, ferrotungsten, and ferrosilicon-manganese alloys, as well as chemical raw materials such as calcium carbide and phosphorus. Their operating characteristics include a furnace lining made of carbonaceous or magnesia refractory materials, and the use of carbon electrodes, graphite electrodes, or self-baking electrodes. The electrodes are inserted into the furnace charge to perform a submerged arc operation. The smelting process utilizes the energy generated by the electric arc and the current passing through the furnace charge, as well as the energy generated by the resistance of the charge. It is an industrial electric furnace that operates continuously with sequential charging and intermittent discharging. The electrodes are the working ends for electrical energy conversion and are considered the "heart" of the submerged arc furnace, playing a crucial role in its operation.

[0003] Currently, the industry uses carbon or graphite electrodes for silicon metal smelting, employing a continuous operation method where electrodes are added as they are consumed. In recent years, with the rapid development of the solar energy industry, the market demand for silicon metal has also experienced explosive growth. Smelting silicon metal in ordinary submerged arc furnaces requires a large investment in equipment upgrades, and the cost of carbon electrodes is more than twice that of electrode paste. As a result, a new type of electrode paste for silicon metal smelting has emerged.

[0004] Traditional electrode paste production primarily uses calcined coal as aggregate, petroleum coke as powder, and adds an appropriate amount of graphite powder. The softening temperature of the binder, coal tar pitch, is adjusted to achieve this. Traditional electrode paste suffers from drawbacks such as high raw material costs, low formulation precision, low strength, high resistivity, poor thermal shock resistance after sintering, and unstable product quality. These issues lead to insufficient electrode sintering speed and frequent electrode failures during silicon metal smelting.

[0005] Ordinary electrode paste is made from aggregates such as calcined anthracite, calcined petroleum coke, metallurgical coke, and artificial graphite fragments. These are crushed, ground, sieved, and batched, with coal tar pitch and coal tar as binders, and then kneaded and stretched into a paste shape. Metallurgical silicon electrode paste, due to its high smelting temperature and rapid electrode consumption, is not conducive to the baking of the electrode paste. Therefore, it requires low ash content, high thermal conductivity, and low resistivity, as well as good plasticity and poor flowability to improve the baking rate. Summary of the Invention

[0006] The purpose of this invention is to provide a metal silicon electrode paste with low raw material cost, high process control precision, high strength, low resistivity and excellent thermal shock resistance, and its manufacturing method. When this electrode paste is used in a metal silicon submerged arc furnace, it can effectively avoid problems such as hard breakage, soft breakage and paste flow of self-baking electrodes caused by electrode paste quality, and fully meet the requirements of the smelting process.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0008] An electrode paste for smelting metallic silicon is manufactured using carbon raw materials as aggregates and organic compounds as binders through processes such as crushing, screening, grinding, batching, binder melting, dry mixing, wet mixing, and paste forming. By weight percentage, it comprises 78%-80% carbon aggregates and 20%-22% organic binders. The carbon aggregates include 10% electric calcined anthracite, 10%-15% calcined petroleum coke, 20%-25% pitch coke, 30% residual anode, 17%-20% artificial graphite, and 5%-8% natural earthy graphite. The organic binders include 90% medium-temperature pitch and 10% anthracene oil.

[0009] Furthermore, the carbon aggregate comprises 80% and the organic binder comprises 20%. The carbon aggregate, by weight percentage, includes 10% electrically calcined anthracite, 10% calcined petroleum coke, 25% pitch coke, 30% residual anode, 20% artificial graphite, and 5% natural earthy graphite. The organic binder, by weight percentage, includes 90% medium-temperature pitch and 10% anthracene oil.

[0010] Further, the above-mentioned carbon aggregates are subjected to crushing, grinding, and screening. The electrically calcined anthracite is crushed to below 30mm and screened into granular materials of 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. The residual anode is crushed to below 30mm and screened into granular materials of 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. The artificial graphite is crushed to below 20mm and screened into granular materials of 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. Particles of various sizes: 4mm, 5-8mm, 9-12mm, and 13-20mm; natural earth-like graphite is crushed to below 4mm and sieved into 0-4mm particles; calcined petroleum coke is ground into powder, and the purity of the ground calcined petroleum coke powder at -200 mesh (-0.075mm) is 68%; pitch coke is ground into powder, and the purity of the ground pitch coke powder at -200 mesh (-0.075mm) is 68%.

[0011] Further, the above-mentioned carbon aggregates are proportioned as follows (by weight): 1% of calcined anthracite (0-4mm), 2% of 5-8mm, 3% of 9-12mm, 3% of 13-20mm, and 1% of 21-30mm; 4% of residual anode (0-4mm), 6% of 5-8mm, 6% of 9-12mm, 6% of 13-20mm, and 8% of 21-30mm; 1% of artificial graphite (0-4mm), 6% of 4-8mm, 6% of 8-12mm, and 7% of 12-20mm; 5% of natural earthy graphite (0-4mm); 10% of calcined petroleum coke powder; and 25% of pitch coke powder.

[0012] Furthermore, after mixing the granular and powder materials of the above proportions, the mixture is sieved (by weight percentage). The particle composition is as follows: 21-30mm accounts for 9%, 13-20mm accounts for 18%, 9-12mm accounts for 13%, 5-8mm accounts for 8%, less than 0.075mm accounts for 27%, and 0.075-4mm accounts for 25%.

[0013] Furthermore, the method for manufacturing this electrode paste for smelting metallic silicon includes the following steps:

[0014] (1) The carbon aggregate is crushed, screened, ground and batched according to the above raw material ratio and particle size distribution;

[0015] (2) Add the prepared carbon aggregate to the mixing pot for dry mixing, so that the temperature of the carbon aggregate reaches 100℃;

[0016] (3) Heat the medium-temperature asphalt to 160-170°C to melt it, then add it to the mixing pot and wet mix it with carbon aggregate, and continue heating to raise the temperature to 140-150°C, and continue wet mixing at this temperature for 30-40 minutes.

[0017] (4) Heat the anthracene oil to 80-90°C, add it to the mixing pot, continue mixing for 15 minutes and remove from the pot;

[0018] (5) The paste after being taken out of the pot is stretched and shaped on the paste stretching machine while it is still hot, thus making the metal silicon electrode paste.

[0019] Advantages and beneficial effects of the present invention:

[0020] This invention, applied to a submerged arc furnace for smelting silicon metal, not only meets the requirements of silicon metal smelting but also reduces smelting costs and increases smelting efficiency. It improves the strength of the electrode paste, reduces its resistivity, increases the sintering speed, and enhances the thermal shock resistance of the sintered electrode. The manufacturing process of the electrode paste increases the number of particle size classification stages, resulting in more rational and stable ingredient proportions. Reasonable heating of the anthracene oil and control of the electrode paste's flowability ensure sintering speed, thereby maintaining stable product quality and meeting the requirements of silicon metal smelting.

[0021] The metallic silicon electrode paste manufactured by this invention has a resistivity of less than 50 μΩ·m, a compressive strength of greater than 20 MPa, a bulk density of greater than 1.48 g / cm³, an ash content of less than 2%, and a volatile matter content between 11% and 13%. It is suitable for use in submerged arc furnaces for smelting metallic silicon, exhibiting excellent thermal shock resistance and reducing the likelihood of electrode breakage accidents when used in submerged arc furnaces, thus fully meeting the requirements for metallic silicon smelting.

[0022] The metal silicon electrode paste manufactured by this invention reduces the roasting and processing steps compared to carbon electrodes. It also reduces the amount of electric anthracite used in the batching and increases the amount of residual anode. The residual anode is a material discarded by aluminum plants. The production cost is equivalent to one-third of that of carbon electrodes, while the consumption increases from 94 kg / ton to 110 kg / ton, which is only an increase of 17%. Overall, it reduces the cost of metal silicon smelting.

[0023] The metal silicon electrode paste manufactured in this invention uses a large amount of artificial graphite and natural earthy graphite in its formulation, which reduces the specific resistance of the electrode paste.

[0024] The metal silicon electrode paste manufactured in this invention uses pitch coke as powder in the ingredients, which improves the strength of the electrode paste and makes the sintered electrode close to the properties of a carbon electrode.

[0025] The metal silicon electrode paste manufactured by this invention increases the proportion of low-ash raw materials such as calcined petroleum coke, pitch coke, residual anode, and artificial graphite in the ingredients, thereby improving the thermal shock resistance of the electrode paste when sintered into a self-baking electrode and effectively preventing electrode accidents in metal silicon smelting.

[0026] The metal silicon electrode paste provided by this invention produces a significant synergistic effect through a unique combination of raw materials (high proportion of residual anode, artificial / natural graphite, pitch coke and anthracene oil modified binder). This synergistic effect is directly reflected in the key performance indicators of the electrode paste: significantly improved strength (compressive strength >20MPa), significantly reduced resistivity (<50μΩ·m), and excellent thermal shock resistance.

[0027] Practical industrial applications have verified its superior performance: When used in large-scale silicon metal submerged arc furnaces (such as 33000KVA), this electrode paste effectively avoids core problems such as hard breakage, soft breakage, and paste flow in self-baking electrodes caused by electrode paste quality. Specifically, the optimized formula (Example 3) significantly reduces black smoke and flames during electrode pressing and releasing, ensuring safe pressing and releasing every 40 minutes, and achieving a good match between the electrode sintering rate and consumption rate.

[0028] Final result: The electrode paste fully meets the stringent process requirements of high-temperature, rapid-consumption, and continuous smelting of metallic silicon. While ensuring stable and reliable operation of the electrode, it significantly reduces the overall smelting cost (thanks to the efficient utilization of residual anodes and process simplification). Detailed Implementation

[0029] The present invention will be further described in conjunction with the following specific embodiments:

[0030] Example 1

[0031] An electrode paste for smelting metallic silicon comprises, by weight percentage, 78% carbon aggregate and 22% organic binder.

[0032] The carbon aggregate, by weight percentage, includes 10% electric calcined anthracite, 15% calcined petroleum coke, 20% pitch coke, 30% residual anode, 17% artificial graphite, and 8% natural earthy graphite.

[0033] The organic binder, by weight percentage, comprises 90% medium-temperature bitumen and 10% anthracene oil.

[0034] The above-mentioned carbon aggregates, including electrically calcined anthracite, calcined petroleum coke, pitch coke, residual anode, artificial graphite, and natural earthy graphite, are subjected to crushing, grinding, and screening. The electrically calcined anthracite was crushed to below 30mm and sieved into granular materials of various sizes: 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. Residual anodes were crushed to below 30mm and sieved into granular materials of various sizes: 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. Artificial graphite was crushed to below 20mm and sieved into granular materials of various sizes: 0-4mm, 5-8mm, 9-12mm, and 13-20mm. Natural earthy graphite was crushed to below 4mm and sieved into granular materials of 0-4mm. Calcined petroleum coke was ground into powder, and the purity of the ground calcined petroleum coke powder (-200 mesh, -0.075mm) was 68%. Pitch coke was ground into powder, and the purity of the ground pitch coke powder (-200 mesh, -0.075mm) was 68%.

[0035] The above carbon aggregates are proportioned as follows (by weight): 1% of calcined anthracite (0-4mm), 2% of 5-8mm, 3% of 9-12mm, 3% of 13-20mm, and 1% of 21-30mm; 2% of residual anode (0-4mm), 5% of 5-8mm, 9% of 9-12mm, 12% of 13-20mm, and 2% of 21-30mm; 2% of artificial graphite (0-4mm), 3% of 5-8mm, 5% of 9-12mm, and 7% of 13-20mm; 8% of natural earthy graphite (0-4mm); 15% of calcined petroleum coke powder; and 20% of pitch coke powder.

[0036] After mixing the granular and powder materials of the above proportions, the mixture is sieved (by weight percentage). The particle composition is as follows: 21-30mm accounts for 4%, 13-20mm accounts for 21%, 9-12mm accounts for 17%, 5-8mm accounts for 9%, less than 0.075mm accounts for 25%, and 0.075-4mm accounts for 24%.

[0037] In this example, the performance of the electrode paste prepared in this example was tested according to the industry standard "YB / T5215-2015 Electrode Paste", and the test results are shown in Table 1.

[0038] Example 2

[0039] An electrode paste for smelting metallic silicon comprises, by weight percentage, 79% carbon aggregate and 21% organic binder.

[0040] The carbon aggregate, by weight percentage, includes 10% electric calcined anthracite, 15% calcined petroleum coke, 20% pitch coke, 30% residual anode, 17% artificial graphite, and 8% natural earthy graphite.

[0041] The organic binder, by weight percentage, comprises 90% medium-temperature bitumen and 10% anthracene oil.

[0042] The above-mentioned carbon aggregates, including electrically calcined anthracite, calcined petroleum coke, pitch coke, residual anode, artificial graphite, and natural earthy graphite, are subjected to crushing, grinding, and screening. The electrically calcined anthracite was crushed to below 30mm and sieved into granular materials of various sizes: 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. Residual anodes were crushed to below 30mm and sieved into granular materials of various sizes: 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. Artificial graphite was crushed to below 20mm and sieved into granular materials of various sizes: 0-4mm, 5-8mm, 9-12mm, and 13-20mm. Natural earthy graphite was crushed to below 4mm and sieved into granular materials of 0-4mm. Calcined petroleum coke was ground into powder, and the purity of the ground calcined petroleum coke powder (-200 mesh, -0.075mm) was 68%. Pitch coke was ground into powder, and the purity of the ground pitch coke powder (-200 mesh, -0.075mm) was 68%.

[0043] The above carbon aggregates are proportioned as follows (by weight): 1% of calcined anthracite (0-4mm), 2% of 5-8mm, 3% of 9-12mm, 3% of 13-20mm, and 1% of 21-30mm; 2% of residual anode (0-4mm), 5% of 5-8mm, 9% of 9-12mm, 12% of 13-20mm, and 2% of 21-30mm; 2% of artificial graphite (0-4mm), 3% of 5-8mm, 5% of 9-12mm, and 7% of 13-20mm; 8% of natural earthy graphite (0-4mm); 15% of calcined petroleum coke powder; and 20% of pitch coke powder.

[0044] After mixing the granular and powder materials of the above proportions, the mixture is sieved (by weight percentage). The particle composition is as follows: 21-30mm accounts for 4%, 13-20mm accounts for 21%, 9-12mm accounts for 17%, 5-8mm accounts for 9%, less than 0.075mm accounts for 25%, and 0.075-4mm accounts for 24%.

[0045] In this example, the performance of the electrode paste prepared in this example was tested according to the industry standard "YB / T5215-2015 Electrode Paste", and the test results are shown in Table 1.

[0046] Example 3

[0047] An electrode paste for smelting metallic silicon, the raw material composition by weight percentage includes 80% carbon aggregate and 20% organic binder.

[0048] The carbon aggregate, by weight percentage, comprises 10% electric calcined anthracite, 10% calcined petroleum coke, 25% pitch coke, 30% residual anode, 20% artificial graphite, and 5% natural earthy graphite.

[0049] The organic binder, by weight percentage, comprises 90% medium-temperature bitumen and 10% anthracene oil.

[0050] The above-mentioned carbon aggregates, including electrically calcined anthracite, calcined petroleum coke, pitch coke, residual anode, artificial graphite, and natural earthy graphite, are subjected to crushing, grinding, and sieving. The electrically calcined anthracite was crushed to below 30mm and sieved into granular materials of various sizes: 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. Residual anodes were crushed to below 30mm and sieved into granular materials of various sizes: 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. Artificial graphite was crushed to below 20mm and sieved into granular materials of various sizes: 0-4mm, 5-8mm, 9-12mm, and 13-20mm. Natural earthy graphite was crushed to below 4mm and sieved into granular materials of 0-4mm. Calcined petroleum coke was ground into powder, and the purity of the ground calcined petroleum coke powder (-200 mesh, -0.075mm) was 68%. Pitch coke was ground into powder, and the purity of the ground pitch coke powder (-200 mesh, -0.075mm) was 68%.

[0051] The above carbon aggregates are proportioned as follows (by weight): 1% of calcined anthracite (0-4mm), 2% of 5-8mm, 3% of 9-12mm, 3% of 13-20mm, and 1% of 21-30mm; 4% of residual anode (0-4mm), 6% of 5-8mm, 6% of 9-12mm, 6% of 13-20mm, and 8% of 21-30mm; 1% of artificial graphite (0-4mm), 6% of 4-8mm, 6% of 8-12mm, and 7% of 12-20mm; 5% of natural earthy graphite (0-4mm); 10% of calcined petroleum coke powder; and 25% of pitch coke powder.

[0052] After mixing the granular and powder materials of the above proportions, the mixture is sieved (by weight percentage). The particle composition is as follows: 21-30mm accounts for 9%, 13-20mm accounts for 18%, 9-12mm accounts for 13%, 5-8mm accounts for 8%, less than 0.075mm accounts for 27%, and 0.075-4mm accounts for 25%.

[0053] A method for manufacturing electrode paste for smelting metallic silicon includes the following steps:

[0054] (1) The carbon aggregate is crushed, screened, ground and batched according to the above raw material ratio and particle size distribution;

[0055] (2) Add the prepared carbon aggregate to the mixing pot for dry mixing, so that the temperature of the carbon aggregate reaches 100℃;

[0056] (3) Heat the medium-temperature asphalt to 160-170°C to melt it, then add it to the mixing pot and wet mix it with carbon aggregate, and continue heating to raise the temperature to 140-150°C, and continue wet mixing at this temperature for 30-40 minutes.

[0057] (4) Heat the anthracene oil to 80-90°C, add it to the mixing pot, continue mixing for 15 minutes and remove from the pot;

[0058] (5) The paste after being taken out of the pot is stretched and shaped on the paste stretching machine while it is still hot, thus making the metal silicon electrode paste.

[0059] The raw materials used in the above embodiments were all purchased from the market and are ordinary raw materials without any special requirements.

[0060] In this example, the performance of the electrode paste prepared in this example was tested according to the industry standard "YB / T5215-2015 Electrode Paste", and the test results are shown in Table 1.

[0061] Table 1:

[0062] Group Project Example 1 Example 2 Example 3 National Standard Requirements Ash content % 1.32 1.38 1.42 Less than 4 Volatile matter % 12．64 12.15 11.53 11.5-15.5 Resistivity μΩ·m 48.6 47.8 47.6 Less than 68 compressive strength (MPa) 20.6 22.4 23.6 Greater than 18 Bulk density g / cm3 1.49 1.50 1.50 Greater than 1.42 Flow coefficient 1.1 1.0 0.86 ---

[0063] As shown in Table 1, the electrode paste prepared by this invention has low ash content, low resistivity, and high mechanical strength. In particular, its resistivity is about 30% lower than the industry standard, and other indicators are superior to the industry standard. It also has low smelting consumption and fully meets the requirements for smelting metallic silicon. Analysis of the results of the three embodiments shows that due to different binder dosages, the volatile matter content fluctuates significantly. The compressive strength increases slightly with decreasing volatile matter content, while other indicators remain relatively unchanged.

[0064] The silicon metal electrode pastes prepared in the above embodiments were tested on a 33000KVA silicon metal submerged arc furnace in a ferroalloy plant. The silicon metal electrode paste prepared in Example 1 had a slow sintering speed, with a large amount of black smoke and flames of 150-200mm length emerging during electrode pressing. Pressing the electrode every 40 minutes posed a risk of soft breakage. Adjustments were made according to Example 2, resulting in a significantly improved silicon metal electrode paste. Although a large amount of black smoke still emerged during pressing, the flame length was reduced to 50-100mm, ensuring a pressing of approximately 50mm every 40 minutes. Further adjustments were made, resulting in Example 3. Example 3 reduced the amount of anthracene oil added, partly to lower the volatile content of the electrode paste and partly to reduce black smoke and flames during electrode pressing. After repeated experiments with the three formulations, it was found that the electrode paste prepared in Example 3 only produced a small amount of black smoke during electrode pressing, with no flames generated. Pressing every 40 minutes posed no risk and fully met the requirements for silicon metal smelting. The cost of smelting silicon metal electrodes using this electrode paste is 44 yuan / ton, while the cost of smelting silicon metal electrodes using carbon electrodes or graphite electrodes is 92-100 yuan / ton. The cost per ton of silicon metal can be reduced by at least 48 yuan / ton, resulting in considerable economic benefits.

Claims

1. An electrode paste for smelting metallic silicon, characterized in that, It is manufactured using carbon raw materials as aggregates and organic compounds as binders through processes such as crushing, screening, grinding, batching, binder melting, dry mixing, wet mixing, and stretching and molding. By weight percentage, it includes 78%-80% carbon aggregates and 20%-22% organic binders. The carbon aggregates include 10% electric calcined anthracite, 10%-15% calcined petroleum coke, 20%-25% pitch coke, 30% residual anode, 17%-20% artificial graphite, and 5%-8% natural earthy graphite. The organic binders include 90% medium-temperature pitch and 10% anthracene oil.

2. The electrode paste for smelting metallic silicon according to claim 1, characterized in that, The carbon aggregate comprises 80% carbon and 20% organic binder. The carbon aggregate, by weight percentage, includes 10% electric calcined anthracite, 10% calcined petroleum coke, 25% pitch coke, 30% residual anode, 20% artificial graphite, and 5% natural earthy graphite. The organic binder, by total weight percentage, comprises 90% medium-temperature bitumen and 10% anthracene oil.

3. The electrode paste for smelting metallic silicon according to claim 2, characterized in that, The above-mentioned carbon aggregates are crushed, ground, and sieved. The electrically calcined anthracite is crushed to below 30mm and sieved into granular materials of 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. The residual anode is crushed to below 30mm and sieved into granular materials of 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. The artificial graphite is crushed to below 20mm and sieved into granular materials of 0-4mm, 5-8mm, 9-12mm, 13-20mm, and 21-30mm. Particles of various sizes: 4mm, 5-8mm, 9-12mm, and 13-20mm; natural earth-like graphite is crushed to below 4mm and sieved into 0-4mm particles; calcined petroleum coke is ground into powder, and the purity of the ground calcined petroleum coke powder at -200 mesh (-0.075mm) is 68%; pitch coke is ground into powder, and the purity of the ground pitch coke powder at -200 mesh (-0.075mm) is 68%.

4. The electrode paste for smelting metallic silicon according to claim 3, characterized in that, The above carbon aggregates are proportioned as follows (by weight): 1% of calcined anthracite (0-4mm), 2% of 5-8mm, 3% of 9-12mm, 3% of 13-20mm, and 1% of 21-30mm; 4% of residual anode (0-4mm), 6% of 5-8mm, 6% of 9-12mm, 6% of 13-20mm, and 8% of 21-30mm; 1% of artificial graphite (0-4mm), 6% of 4-8mm, 6% of 8-12mm, and 7% of 12-20mm; 5% of natural earthy graphite (0-4mm); 10% of calcined petroleum coke powder; and 25% of pitch coke powder.

5. The electrode paste for smelting metallic silicon according to claim 4, characterized in that, After mixing the granular and powder materials of the above proportions, the mixture is sieved (by weight percentage). The particle composition is as follows: 21-30mm accounts for 9%, 13-20mm accounts for 18%, 9-12mm accounts for 13%, 5-8mm accounts for 8%, less than 0.075mm accounts for 27%, and 0.075-4mm accounts for 25%.

6. The method for manufacturing electrode paste for smelting metallic silicon according to claim 5, characterized in that, Includes the following steps: (1) The carbon aggregate is crushed, screened, ground and batched according to the above raw material ratio and particle size distribution; (2) Add the prepared carbon aggregate to the mixing pot for dry mixing, so that the temperature of the carbon aggregate reaches 100℃; (3) Heat the medium-temperature asphalt to 160-170°C to melt it, then add it to the mixing pot and wet mix it with carbon aggregate, and continue heating to raise the temperature to 140-150°C, and continue wet mixing at this temperature for 30-40 minutes. (4) Heat the anthracene oil to 80-90°C, add it to the mixing pot, continue mixing for 15 minutes and remove from the pot; (5) The paste after being taken out of the pot is stretched and shaped on the paste stretching machine while it is still hot, thus making the metal silicon electrode paste.