Evolution of Hot Blast Stoves:

1. 19th Century – Foundations

• Cold Air Era: Early blast furnaces used unheated air, yielding poor efficiency.
• Preheated Air Breakthrough: James Neilson’s 1828 concept raised blast temperatures to ~300°C, cutting coke use by 30%.
• Cowper Stoves (1857): First regenerative stoves using brick regenerators, stabilizing temperatures at 400–600°C.

2. 20th Century – Structural & Material Advances

• Internal Combustion Stoves (1930s): Compact but uneven heating (max 1,000°C), suited for mid-sized furnaces.
• External Combustion Stoves (1960s): Separated chambers improved stability (1,200°C) but cost 30% more.
• Material Upgrades: High-alumina/silica bricks extended lifespans to 15 years.

3. 21st Century – Efficiency & Intelligence

• Top-Combustion Stoves (2000s):

Kalugin Design: Top-mounted burners achieved 85–90% efficiency, 1,250–1,350°C stable blast temps, 30+ year lifespan.

Smart Controls: AI-driven systems reduced temperature fluctuations to ±5°C.

4. Green & Smart Era (2020s+)

• Low-Carbon Tech: Dual preheating cut emissions by 20%; hydrogen trials (e.g., HYBRIT) target zero-carbon operations.
• Ultra-High Temps: Silicon carbide composites aim for 1,450°C.
• Longevity: Modular designs and nano-coatings target 40-year lifespans.

Legacy → Future
From rudimentary heating to AI-optimized, eco-friendly systems, hot blast stoves remain pivotal in steel’s green transition, driven by temperature, efficiency, and sustainability.

Annec's own R&D features:

After 20 years of application accumulation and continuous innovation, on the basis of in-depth research on the operation of various types of hot blast stoves, Annec has continuously optimized the system structure of top combustion hot blast stoves and the standardized configuration of refractory materials. In 2013, the cone-column rotary cutting top combustion hot blast stove was successfully developed, which broke through foreign technical barriers, has completely independent intellectual property rights, and has leading advantages such as high blast temperature, long campaign life, low energy consumption, low emission, and low investment.

Annec cone-column rotary cutting top combustion hot blast stove completely solves the characteristics of traditional hot blast stoves such as low blast temperature, low thermal efficiency, high gas consumption, and high carbon emissions. The specific advantages are as follows:

1. High blast temperature: Compared with other type hot blast stoves, the blast temperature of Annec hot stove is increased by 15°C.

2. Long campaign life: more than 30 years without maintenance.

3. Low energy consumption: the thermal efficiency of the hot stove system is higher than 90%,and the gas consumption is lower than 5%.

4. Low emission: NOx emission is more than 65% lower than the national standard.

5. Low investment: reduce project investment by more than 8%.

International Technology Patent of Annec cone-column rotary cutting top combustion hot blast stove

At present, Annec has cooperated in supplying projects: