Energy efficiency in the steel industry: A solution for cost reduction and carbon emission mitigation

Home
News
Energy efficiency in the steel industry: A solution for cost reduction and carbon emission mitigation

09:34 | 03/04/2025

21/02/2025

May Forestry Joint Stock Company participates in Voluntary Agreement Scheme on Energy Efficiency
Renovating and upgrading billet reheating furnaces for energy efficiency

Discover how thoughtful and scientific research can empower a steel enterprise to unlock feasible energy-saving solution- cutting billions of VND in energy cost and reducing CO2 emissions by hundreds of tons per year.

From Concept to Feasible Project

Identifying Energy Waste

NatSteelVINA is a long-standing steel producer in Vietnam. The enterprise specializes in producing construction steel from steel billets, with an annual production capacity of approximately 172,000 tons.

The enterprise uses pusher-type furnace with heavy oil (FO) usage for combustion fuel. The furnace operates at extreme temperatures, ranging from 1,050 to 1,150°C, ensuring the billets reach the necessary heat level for rolling.

Prior to joining the VAS Program, NatSteelVINA was already aware of inefficiencies in its energy use. According to the previous audit, excessive oxygen levels in exhaust gases was measured as high as 9.8%, and waste heat temperature exceeding 333^oC, indicating substantial energy losses.

To address this challenges, the enterprise decided to participate in the VAS to assist them with exploring high-potential energy-saving measures.

Previous audit revealed subtantial energy losses in reheating furnance process, implying huge energy efficiency opportunity. Photo extracted from the report.

Optimizing Energy Efficiency

To identify the most effective solutions, NatSteelVINA and experts from the VAS Program conducted a three-phase research approach:

Phase 1: Screening Study – International and local experts collaborated to filter out high-potential and practically applicable solutions. From this study, 2 main EE opportunities related to the reheating furnace were identified. One of them- optimization of the control system, was chosen for further analysis.
Phase 2: Pre-Feasibility Study – The solution of control system optimization underwent a detailed technical and economic assessment. This study confirmed that feasible solutions include either upgrading or replacing the furnace control system.
Phase 3: Feasibility Study – The selected solutions were comprehensively analyzed, with experts calculating investment costs, energy savings, payback periods, risks, and operational impacts. This phase provided businesses with a solid foundation for investment decisions.

Two options were proposed for upgrading the billet reheating furnace control system: optimizing the existing control system or replacing it with a new PLC-based control unit. Photo: extracted from FS report.

Key Findings and Results

Following extensive research, optimizing the billet reheating furnace control system was identified as the key energy-saving solution for NatSteelVINA. Studies revealed that by enhancing combustion efficiency, the factory could reduce FO consumption by nearly 3% and maintain excess oxygen levels at an optimal 3%.

An unexpected discovery was that this optimization also reduced oxide scale formation on billets, improving product quality and lowering production costs.

Both proposed solutions for furnace control system upgrades could cut CO₂ emissions by nearly 450 tons per year—offering dual benefits in cost savings and environmental impact reduction.

Both proposed solutions indicate results of significant energy efficiency and CO₂ reduction every year. Photo: extracted from FS report.

Lessons Learned and Future Applications

The research conducted at NatSteelVINA offers valuable insights and potential applications for other steel manufacturers:

A systematic and scientific approach is essential – Identifying effective energy efficiency solutions requires a step-by-step, methodical approach.
Detailed economic and environmental analyses matter – Providing precise calculations of cost savings and emission reductions increases business confidence in making investment decisions. All indirect impacts, like waste, production capacity and quality, should also be taken into consideration for optimizing energy consumption of process equipment.
Optimizing existing technology can yield significant improvements – Combining technological upgrades with scientific advancements can maximize efficiency and sustainability.

Billet reheating furnace technology is widely used in Vietnam’s steel industry, making the findings at NatSteelVINA highly relevant for other enterprises. By adopting a structured research methodology and implementing proven technological solutions, steel manufacturers can improve energy efficiency, reduce emissions, and enhance their competitive edge.

DEPP3 Program

Tags: