The energy consumption and carbon emission issues in the production of graphite electrodes can be systematically optimized through the following multi-dimensional solutions:
I. Raw Material Side: Formula Optimization and Substitution Technologies
1. Needle Coke Substitution and Ratio Optimization
Ultra-high-power graphite electrodes require needle coke (high crystallinity and low thermal expansion coefficient), but its production consumes more energy than petroleum coke. Adjusting the ratio of needle coke to petroleum coke (e.g., 1.1–1.2 tons of needle coke per ton of high-power electrode products) can reduce raw material energy consumption while maintaining performance. For instance, the 600mm large-diameter ultra-high-power electrodes developed in Chenzhou reduced CO₂ emissions from short-process electric arc furnace steelmaking by over 70% through optimized raw material ratios.
2. Enhanced Binder Efficiency
Coal tar pitch, used as a binder and accounting for 25%–35% of raw materials, leaves only 60%–70% residue after baking. Using modified pitch or adding nanofillers can improve binding efficiency, reduce binder usage, and lower volatile emissions during baking.
II. Process Side: Energy-Saving and Consumption Reduction Innovations
1. Graphitization Energy Consumption Optimization
- Internal Series Graphitization Furnace: Compared to traditional Acheson furnaces, this reduces electricity consumption by 20%–30% by heating electrodes in series with resistance materials, minimizing heat loss.
- Low-Temperature Graphitization Technology: Developing new catalysts or optimizing heat treatment processes to lower graphitization temperatures from 2,800°C to below 2,600°C, reducing energy consumption per ton by 500–800 kWh.
- Waste Heat Recovery Systems: Utilizing graphitization furnace waste heat for raw material preheating or power generation improves thermal efficiency by 10%–15%.
2. Baking Fuel Substitution
Replacing heavy oil or coal gas with natural gas increases combustion efficiency by 20% and reduces CO₂ emissions by 15%–20%. High-efficiency baking furnaces with layered heating technology shorten baking cycles, cutting fuel consumption by 10%–15%.
3. Impregnation and Filler Recycling
Modified pitch impregnation agents (0.5–0.8 tons per ton of electrodes) can reduce impregnation cycles through vacuum impregnation technology. Recycling rates of metallurgical coke or quartz sand fillers reach 90%, lowering auxiliary material consumption.
III. Equipment Side: Intelligent and Large-Scale Upgrades
1. Large-Scale Furnaces and Automated Control
Large ultra-high-power (UHP) electric arc furnaces equipped with impedance control systems and in-furnace monitoring reduce electrode breakage rates to below 2% and lower energy consumption per ton by 10%–15%. Intelligent power delivery systems dynamically adjust arc voltage and current peaks based on steel grades and processes, avoiding reactive oxidation losses.
2. Continuous Production Line Construction
End-to-end continuous production from raw material crushing to machining reduces intermediate energy consumption. For example, steam or electric heating in the mixing process cuts energy consumption per ton from 80 kWh to 50 kWh.
IV. Energy Structure: Green Power and Carbon Management
1. Renewable Energy Adoption
Building plants in regions rich in solar or wind resources and using green electricity for graphitization (accounting for 80%–90% of total production electricity) can reduce carbon emissions per ton from 4.48 to below 1.5 tons. Energy storage systems balance grid fluctuations, improving green power utilization.
2. Carbon Capture, Utilization, and Storage (CCUS)
Capturing CO₂ emitted during baking and graphitization for producing lithium carbonate or synthetic fuels enables carbon recycling.
V. Policy and Industrial Collaboration
1. Capacity Control and Industry Consolidation
Strictly limiting new high-energy-consuming capacity and promoting industry concentration (e.g., Fangda Carbon’s 17.18% market share) leverage economies of scale to reduce unit energy consumption. Encouraging vertical integration, such as Fangda Carbon’s self-supply of 67.8% of calcined coke and needle coke, cuts raw material transportation energy use.
2. Carbon Trading and Green Finance
Incorporating carbon costs into product pricing incentivizes emissions reductions. For example, after Japan initiated anti-dumping investigations on Chinese graphite electrodes, domestic firms upgraded technologies to lower carbon tax burdens. Issuing green bonds supports energy-saving retrofits, such as one company reducing its debt-to-asset ratio through debt-to-equity swaps and funding low-temperature graphitization furnace R&D.
VI. Case Study: Emission Reduction Effects of Chenzhou’s 600mm Electrodes
Technical Path: Needle coke ratio optimization + internal series graphitization furnace + waste heat recovery.
Data Comparison:
- Electricity consumption: Reduced from 5,500 kWh/ton to 4,200 kWh/ton (↓23.6%).
- Carbon emissions: Reduced from 4.48 tons/ton to 1.2 tons/ton (↓73.2%).
- Costs: Unit energy costs decreased by 18%, enhancing market competitiveness.
Conclusion
Through raw material optimization, process innovation, equipment upgrades, energy transition, and policy coordination, graphite electrode production can achieve 20%–30% lower energy consumption and 50%–70% reduced carbon emissions. With breakthroughs in low-temperature graphitization and green power adoption, the industry is poised to peak carbon emissions by 2030 and achieve carbon neutrality by 2060.
Post time: Aug-06-2025