Arc kiln

Arc Kiln Market Dynamics and Growth Projections

Market Overview: The global arc kiln market is positioned for steady growth, reflecting a broader trend in the industrial furnace sector. The market for industrial furnaces was estimated at $15.0 billion in 2023 and is projected to reach $23.1 billion by 2030, with a compound annual growth rate (CAGR) of 6.3% during this period, according to Global Industry Analysts. This growth is propelled by increasing demand for energy-efficient heating solutions and advancements in kiln technology. Notably, the U.S. market was valued at approximately $3.9 billion in 2023, while China is expected to experience a remarkable growth rate of 9.6%, reaching $5.4 billion by 2030. This regional insight highlights the potential for arc kilns in both established and emerging markets.

Trends and Consumer Behavior: The arc kiln sector is increasingly influenced by shifts towards sustainable manufacturing practices and the need for reduced carbon emissions. As industries evolve, there is a notable consumer preference for more efficient and environmentally friendly production methods. The Cement Application segment within the broader kiln market is projected to grow significantly, reaching $583.3 million by 2030 with a CAGR of 3.2%. As companies prioritize sustainability, the integration of modern technologies in arc kilns is expected to address customer pain points related to energy consumption and operational efficiency. Major players in the market are adapting their strategies to focus on innovation and customer-centric solutions, ensuring they remain competitive in the evolving landscape.

Types of arc kilns

An arc kiln refers to a kind of electric furnace that carries out the procedure of melting as well as the reflux of materials with an electric arc. It plays a very impactful role in metallurgy. The material to be melted is generally placed between two or more electrodes or beset directly on the electrode. The electric current, which is high, generates heat through electrode radiation as well as arc discharge. Earth is typically the secondary electrode. Furthermore, electric arc furnaces make use of a wide range of steel-making techniques to turn liquid steel into raw steel for the steel industry.

The following paragraphs describe several electric arc furnaces in detail:

• Conarc Furnaces

  The Conarc electric arc furnace transformer with a tap-through bucket or tilting furnace, which is commonly used as a primary vessel for melting and refining steel from scrap or DRI (direct reduced iron) as the main input material. Conarc furnaces utilize a combination of electric arcs and foamy slag to refine the steel simultaneously within the same vessel. This is also known as "melting with slag," a unique feature of Conarc furnaces. The transformers used in Conarc furnaces are crucial for supplying the electric power needed for the arc melting process. They adjust and provide the appropriate voltage and current to the electrodes, ensuring efficient and controlled steel production. Electric arc transformers work by converting alternating current (AC) from the power grid into three-phase AC to supply the furnace. The processed steel has a variety of applications.

• Three-phase Arc Furnaces

  These types of arc kilns/furnaces are also known as conventional EAFs. They comprise an electric supply conductor as well as three electro-furnace electrodes that are generally fixed at the upper section of the furnace roof and submerged in the charge furnace later on. The arc thus produced between the electrodes and the charge leads to the melting of the charge. Three-phase arc furnaces are characterized by their electrode configurations and the three-phase AC power sources supporting multiple industrial applications.

• Six-phase Arc Furnaces

  These furnaces make use of six electrode taps as a substitute for three-electrode systems. The tapping systems are connected in groups of two on common electrode columns, thereby increasing arc length and enhancing power distribution across the charge. Such furnaces usually have low operation costs and provide high efficiency.

• Submerged Arc Furnaces

  An electric arc furnace (EAF) for steelmaking or other metal production consists of a vessel in the shape of an inverted truncated cone lined with high-temperature refractory material. The charge material is electrically heated by the arc between the carbon or graphitized electrodes and the liquid pool formed by the heat of the arc. In submerged arc heating, the electrode is submerged in the charge material to enhance energy transfer.

Specification and Maintenance

• Flexibility: The production schedule is flexible, allowing operators and plant managers to adjust the timetable to meet the changing needs of the market. Work can be done in some shifts, and some processes can be stopped or changed to operate at a different stage.
• Capacity: The capacity of an electric arc furnace steelmaking involves accounting for the monthly capacity production plans, scrap mix ratios, energy factors, and transmitter settings. Implementing a strategy to increase capacity while decreasing energy costs can be beneficial.
• Quality: The chemical behavior of the scrap, hot metal, and steel produced in an electric arc kiln is influenced by the static and dynamic adjustment of electrode consumption. Reduced energy costs are also the outcome of smart adjustments.
• Construction: Electric arc furnaces (EAF) are built with a frame to support the furnace vessel, roof, charging bucket, electrode supports, and hydraulic systems. The furnace vessel consists of a molten steel pot or vat lined with insulation and refractory material to protect the surrounding environment from heat. An electrode composed of three graphite rods conveys electrical energy. A cooling water system prevents overheating during operation, and the waste heat is utilized through a heat recovery system.
• Production process: The production processes used by the electric arc kiln include steel melting, refining, and slag formation. In the melting process, scrap steel is bathed in an oxygen-scrap mix, and oxidation occurs when alloy elements are removed. Slag is generated when impurities are floated on the alloy elements in the molten steel.
• Safety precautions: Safety precautions during operation in an electric arc kiln include ensuring all cooling water is flowing, listening for changes in the arc sound, watching electrode wear, checking for refractory and insulation failures, and being aware of any changes in melt characteristics and reacting immediately. Human operator involvement and oversight are imperative.

General maintenance for an EAF:

• Electrode: A monitored consumption rate is crucial to minimize downtime and electrode changes.
• Refractories: They should be inspected regularly and repaired immediately with a refractory replacement or repair done as soon as possible.
• Cooling systems: Water flow rates are monitored to prevent overheating and component damage, and leaks or blockages are immediately inspected and addressed.

By following these specifications and maintenance recommendations, the performance and reliability of the electric arc kiln can be improved.

Industry Scenarios

• Industrial Materials Melting

  The primary application of electric arc kilns is the melting of industrial materials like metals (particularly steel), glass, and ceramics. This is conducted by creating an electric arc between graphite electrodes and the feedstock situated in the furnace's center. These kilns are hugely prevalent in the steelmaking industry, particularly for special steel grades that necessitate precise chemical compositions and temperature control.

• Metallurgical Applications

  Apart from melting, electric arc kilns perform additional critical tasks in metallurgy, such as refining metals. Impurities can be removed to ensure enhanced quality by adjusting the temperature, oxygen content, and other atmospheric controls within the furnace. Electric arc furnaces also produce non-ferrous metals like copper, zinc, and aluminum. These are typically coupled with electric arc furnaces, which contain specific extraction and processing units for these metals.

• Ceramic and Glass Production

  Glass production industries (whether for containers, float glass, or fiberglass) heavily rely on models of the electric arc furnace designed for glass. This results in a flawless glass devoid of inclusions. Nothing, apart from the electric arcs, is utilized to achieve the required melting temperature. Electric arc kilns thus ensure the excellence of the final product by preserving the glass melting tanks in a pollution-free environment.

• Construction and Refractory Industries

  The construction industry extensively utilizes materials produced by electric arc kilns, such as steel and ceramics (including refractory materials). These materials play a crucial role in infrastructure development, including residential, commercial, and industrial projects. Additionally, the electric arc kiln is a pivotal player in the production of cement. The primary raw material, clinker (along with other additives), is frequently processed and sintered in electric arc furnaces. The high temperatures achieved in these kilns facilitate the formation of cement clinker, which is essential for cement production. Electric arc kilns are instrumental in the cement industry, particularly in the production of slag cement.

How to Choose an Arc Kiln

There are many ways to select an arc furnace. Some of them are based on the industrial application-needs approach, while others rely on technical specifications.

• Industry application: This method matches the physical requirements of the intended material to the kiln's features. For example, a steel mill may prefer an arc furnace with a large capacity to handle high-volume scrap steel melting.
• Material being processed: Different materials have different physical and chemical properties that necessitate specific arc furnace types. For example, zirconia requires a direct current arc furnace because it will create unstable crystals if heated to more than 1,000 degrees.
• Electrodes: Choose the suitable arc furnace electrodes that can conduct enough electricity to heat the material. For example, a titanium dioxide slag requires a self-baked electrode to produce titanium dioxide.(A self-baked electrode is an electrode that is formed and consumed during the smelting process.)
• Temperature requirements: Match the furnace type to the material's melting point. For example, a material with a melting point of 1,800 degrees requires a furnace rated for that temperature and above.
• Furnace capacity: Select a furnace size based on tonnage per hour of output needed. For example, if production requirements are sufficient to process 500 metric tons of material monthly, then a 10 MT (metric ton) electric arc furnace with a suitable amount of heat would be chosen to meet that monthly capacity.
• Energy source: An energy source must be chosen, like electricity, for an electric arc kiln or wood, for an indirect arc kiln. The energy source should be used to provide economic sustainability.
• Age: New or old, the arc furnace's age affects things like technology, efficiency, and maintenance history. A modern arc furnace is preferred for its faster melting times and lower energy costs.
• Cost-effectiveness: An economic analysis needs to be conducted by calculating costs per ton of material processed to consider purchase price, energy costs, and electrode and electrode consumption per ton of material. This is the most critical factor in helping the buyer make a final decision.

Arc kiln Q & A

Q1 Are there other names for an arc furnace kiln?

A1 Yes. Some people call it an electric arc furnace or electric arc furnaces.

Q2 Who invented the electric arc kiln?

A2 The credit for inventing the electric arc furnace goes to Dr. engineer Stassano in 1907.

Q3 What are the trends in the electric arc kiln market?

A3 The electric arc kiln market is moving toward more sustainable practices. Manufacturers are aiming at furnaces with higher energy efficiency. There is a rise in demand for furnaces that can use scrap combined with other raw materials. There is also a growing preference for furnaces with smart furnaces that have automation and monitoring features.

Q4 What are the challenges facing the electric arc kiln market?

A2 The main challenge factors for the market are the high initial costs connected to installing electric arc kilns. Not all areas of the globe have stable electric power supply. This makes the electric arc kiln a less suitable option. The scrap steel quality may vary if the electric arc kiln manufacturer does not have direct control over the supply chain.