What Can a 9 MVA Submerged Arc Furnace Smelt?

The 9 MVA submerged arc furnace is a medium-power electric furnace widely used in metallurgical and industrial materials production. It is primarily used for smelting ferroalloys, such as silicon-manganese alloys, ferrochrome, and ferronickel.

This type of melting furnace produces high-grade metals through electric arc heating and is widely used in the steel industry and non-ferrous metal processing. Its high-power characteristics make it suitable for continuous, large-scale smelting operations, especially for alloy preparation processes requiring high-temperature reduction reactions.

9MVA Submerged Arc Furnace Smelting Products & Characteristics

Submerged arc furnaces utilize the heat energy generated between the electrodes embedded in the furnace charge and the furnace bottom, as well as the resistance heat of the charge itself, to perform high-temperature smelting under air-isolated or controlled atmosphere conditions.

This type of furnace is ideal for producing products requiring high temperatures, reducing or protective atmospheres, and with relatively flexible requirements for raw material purity. The following are common smelting applications and characteristics of the 9MVA SAF:

1. Ferroalloy Smelting

This is the most classic application area for SAFs, especially for producing "high-carbon" ferroalloys.

Typical Products:

• High-carbon ferrochrome: A key raw material for stainless steel production. High-carbon ferromanganese: Deoxidizer and alloying additive in steelmaking.

• Silicon-manganese alloy: The most widely used composite deoxidizer and alloying agent.

• Ferronickel: Used in stainless steel production, smelted directly from laterite nickel ore.

Smelting characteristics:

• Reduction smelting: Utilizes carbonaceous reducing agents (coke, coal) to reduce metal oxides in the ore.

• High charge resistivity: The charge contains a large amount of coke and ore, resulting in high resistivity, suitable for submerged arc operation, and high thermal energy utilization.

• Continuous tapping: Typically a three-phase open or semi-closed furnace, allowing for almost continuous charging and intermittent tapping, resulting in high production efficiency.

• High carbon content in the product: Due to the use of carbon reduction, the final alloy usually has a high carbon content.

• Suitable for 9MVA furnaces: For ferrochrome, ferromanganese, etc., 9MVA is a medium to small-sized electric furnace, suitable for producing special alloys or for small to medium-scale production, offering relatively flexible investment and operation.

2. Industrial Silicon/Metallic Silicon Smelting

Typical Product: Industrial silicon with a purity of approximately 98.5%, a fundamental raw material for the production of organosilicon, polycrystalline silicon, aluminum alloys, etc.

Smelting Characteristics:

• Strong Reducing Smelting: Silicon dioxide (quartz) is reduced with carbon; the chemical reaction requires extremely high temperatures (>1800℃).

• High Raw Material Purity Requirements: Strict control is required on the impurity content of quartz and reducing agents (charcoal, petroleum coke, coal), especially iron, aluminum, and calcium.

• Complex Furnace Atmosphere: Generates a large amount of SiO gas, which easily burns or condenses at the furnace mouth, requiring meticulous furnace condition management.

• Extremely High Energy Consumption: One of the smelting products with the highest unit electricity consumption. A 9MVA submerged arc furnace is a common furnace type for producing industrial silicon and is one of the mainstream furnace types in the industry, with mature technology.

3. Calcium Carbide (Calcium Carbide) Smelting

Typical Product: Calcium carbide reacts with water to produce acetylene gas, an important basic chemical raw material.

Smelting Characteristics:

• "Charge charge melting-reaction" process: Raw materials quicklime and carbonaceous materials (semi-coke, coke) directly react at high temperatures to generate calcium carbide melt.

• Extremely high operating temperature: The reaction zone temperature needs to reach 2000-2200℃.

• Requirements for raw material particle size: Suitable ratios and particle sizes of lime and carbonaceous materials are required to ensure the permeability and electrical resistance of the charge.

• High requirements for the furnace body: Severe erosion of the furnace lining necessitates high requirements for the lining materials and construction. The 9MVA electric furnace is one of the standard furnace types in the calcium carbide industry, suitable for large-scale production.

4. Yellow Phosphorus Smelting

Typical product: Elemental phosphorus, used in the production of phosphoric acid, phosphates, food additives, flame retardants, etc.

Smelting characteristics:

• Reduction under "air-isolated" conditions: A mixed charge of phosphate rock, silica, and coke is heated in a completely sealed furnace, and phosphorus escapes in vapor form.

• Requirement for a condensation system: Furnace gas is recovered through water cooling or a condenser to obtain liquid or solid yellow phosphorus.

• Strict environmental requirements: Exhaust gas (mainly carbon monoxide) needs proper treatment or utilization, and slag and ferrophosphate byproducts also require treatment.

• Suitable for closed furnaces: Three-phase fully enclosed submerged arc furnaces are typically used. A 9MVA melting furnace is a feasible and common configuration in this field.

5. Corundum (brown corundum, off-white corundum, etc.) smelting

Typical products: Synthetic corundum, a high-quality refractory material and abrasive.

Smelting characteristics:

• Melting & crystallization process: Raw materials such as bauxite, carbon materials, and iron filings are melted at high temperatures. Impurities (oxides of iron, silicon, and titanium) are reduced, causing alumina to accumulate and crystallize.

• Pouring or molten block method: Typically, intermittent operation is used. After smelting, the molten liquid is poured out or cooled directly into molten blocks within the furnace.

• Erosion of furnace lining: The melt is highly alkaline, causing chemical erosion of the furnace lining. Submerged electric furnace is considered medium-sized furnaces in this field, suitable for the flexible production of various corundum products.

6. Other Specialized Smelting

• Titanium Slag Smelting: Smelting ilmenite to produce high-titanium slag (used in titanium dioxide or sponge titanium production) and by-product iron.

• Copper Matte/Copper Sulfide Smelting: Processing copper sulfide ore, but this area is increasingly being replaced by flash furnaces.

• Slag Treatment: Environmental projects such as stainless steel dust recovery and chromium slag detoxification.

In short, a 9 MVA submerged arc furnace is a versatile tool, particularly adept at smelting relatively inexpensive ores or raw materials into high-value-added ferroalloys, industrial silicon, calcium carbide, yellow phosphorus, and other basic industrial materials under high-temperature and reducing conditions. Its specific configuration (such as furnace type, electrode system, and dust removal system) varies significantly depending on the products being smelted.

Submerged arc furnaces are highly adaptable to raw materials, using lump ore, fine ore (requiring pelletizing or sintering), recycled materials, and more. They are suitable for producing high-carbon, high-silicon, high-melting-point metallic or non-metallic products, typically produced in molten form. In all the above industries, it is a mainstream or common SAF furnace type, which takes into account output, investment cost and operational flexibility.