In accordance with the energy saving program worked out by the personal initiative of the Chairman of the Board of Zaporizhstal JSC V.A. Satskiy, the introduction of new jet-niche burners has enhanced efficiency and reduced expenditures significantly.
In 2008, the introduction of new jet-niche burners in the open-hearth furnace shop, blast furnace shop, and sintering plant progressed. The jet-niche technology for fuel combustion, with controlled flow of fuel and oxidizer, is based on uniform distribution of gas in the air flow with the formation of a stable swirling structure. This setup facilitates mixture formation and combustion stabilization while ensuring self-cooling of the burner module. The burners provide intense stable burning with a short flame, accommodating considerable fluctuations in gas pressure in the network, optimizing the coefficient of air excess in the burner device, reducing heat losses, and increasing the coefficient of efficiency. Furthermore, they ensure ecological indices are maintained below the maximum allowed levels, conforming to European ecological norms.
For Zaporizhstal shops, the Works “Spetsgazprom” has developed several types of burners according to technical assignments: СНГ-33М for furnace roofs ДСПА-1, СНГ-33ВС for roofs of open-hearth furnaces, СНГ-21 for mixers, СНГ-22 for drying steel pouring ladles in the open-hearth furnace shop, and СНГ-22АГ for sintering machines and drying hot-metal ladle cars in the blast furnace shop. Thermal conditions have been tailored for each type of burners and each type of thermal generating units. The usage of jet-niche burners in 2008 allowed for a reduction of natural gas consumption by 35,809.76 thousand m³ (or 41,181 tons of fuel equivalent) and led to a significant decrease in expenditures by 22.907 million UAH.
In 2009, this work continued. In open-hearth furnaces Nos. 2, 5, 7, 8, and 10, new jet-niche burners СНГ-55СВ were installed for end heating of the open-hearth furnaces. The old gas burners of an outdated design with oxygen conversion for heating the working area were insufficient for effective fuel combustion. Due to the large size of the furnaces and the consumption of natural gas and air, the mixing process was inadequate. To counter incomplete burning of fuel, excess air was introduced into the furnace. Additionally, the mentioned conversion burners did not provide the required flame rigidity and flame length with natural gas pressures below 2 kgf/cm². The new СНГ-55СВ jet-niche burner reduces the natural gas consumption by 500 m³/hour at a significantly lower gas pressure of 2-3 times. Research on open-hearth furnaces revealed an increase in regenerator checkerwork temperature up to 1000°C from 970°C, leading to improved heating of the regenerative air, while the temperature in the furnace flue rose to 690°C from 670°C. The increased furnace pressure helped minimize cold air leaks.
The content of oxygen in the exhaust gases has diminished to 5.2% from 11.0%. This reduction indicates complete fuel combustion in the working area of the furnace, with carbon oxide levels in the exhaust gases dropping to 0%.
In March 2009, during the operation of the burners at a gas pressure of 1.6-1.7 kgf/cm², an economy of natural gas up to 6.6 kg equivalent fuel/ton was achieved.
The implementation of jet-niche burners on the roofs and for heating the ends of open-hearth furnaces represents a significant scientific and technical thermal advancement of these metallurgical aggregates, a success achieved through the collaborative efforts of open-hearth furnace specialists and all engineering services at the Works.