Classification and Advantages and Disadvantages of Ladle Dryers

Ladle and Cask Dryers: Before the first construction and before filling with molten steel, ladles must undergo a strict baking process. In this process, the ladle dryer plays a crucial role. Newly built ladles need to be slowly dried according to the characteristics of the refractory materials to ensure their service life. Before filling with molten steel, the wall temperature needs to be raised to a higher level through high-temperature baking.

Classification and Advantages and Disadvantages of Ladle Dryers: In the steel production process, ladle dryers are widely used, and their performance directly affects production efficiency and product quality.

This article will compare and analyze the technological characteristics of various ladle dryers and explore the approaches and methods for energy-saving transformation. First, we will briefly introduce various types of dryers.

Ladle and Cask Dryers: After the first construction and before filling with molten steel, ladles must undergo a strict baking process. Newly built ladles need to be slowly dried according to the characteristics of the refractory materials to extend the service life of the lining. Before filling with molten steel, high-temperature baking is required to raise the wall temperature to a higher level, thereby reducing the temperature difference between the molten steel and the wall. Such a high-temperature wall not only prevents molten steel adhesion but also ensures the quality of the molten steel. During the baking process, the intermediate reheating stage requires a fast baking speed and high temperature. For new ladles and repaired ladles, slow baking is required in the low-temperature stage according to the characteristics of the refractory materials, while rapid heating is required in the high-temperature stage before putting into use.

The types of ladle dryers commonly used in major steel plants include direct-fired, self-preheating, and regenerative types. These different types of dryers each have their unique technological characteristics and advantages and disadvantages.

Direct-fired Dryer It follows traditional baking methods, where air and gas are premixed and undergo vigorous combustion inside the ladle, and the flue gas produced by combustion is directly discharged through the ladle mouth. In early steel plants, due to insufficient attention to dryers, the baking equipment used was often rudimentary, and there were even cases of directly connecting gas pipes for combustion baking. Later, steel plants improved the burner and adopted a self-aspirating design. This type of burner does not require a blower and uses the kinetic energy of the gas itself to draw in the surrounding air. However, it is worth noting that because the relationship between the gas flow rate and the induced air flow rate is not linear, the stability of the air-fuel ratio is questionable. Our company's direct-fired dryer uses the LGB dryer as its core component, a product that stands out for its unique design. The LGB burner uses innovative annular flat-slit gas jet technology, with annular air jets on both sides. The dryer is equipped with an independent blower for air distribution, further enhancing combustion stability. Our company's direct-fired dryer is not only compact in structure and easy to operate and maintain but is also equipped with an independent blower for air distribution, reducing the excess air coefficient. The mixing process of air and gas is very intense, ensuring complete combustion and thus producing a higher flame temperature. In addition, the dryer has excellent flame stiffness, its length can even reach the bottom of the ladle, and its capacity and adjustment range are also quite wide, showing strong adaptability to pressure changes in gas and air.

Self-preheating Dryer Its characteristic is that it has a built-in metal heat exchanger, so that after the flue gas is induced by the air, it can heat the air and gas through the heat exchanger before being discharged. This design reduces flue gas loss to a certain extent and improves baking efficiency. However, due to the inherent limitations of direct-fired dryers, there are still limitations on the size of the heat exchanger, resulting in the heat recovery efficiency of the flue gas still needing improvement.

Regenerative Combustion Technology By alternately switching pairs of regenerators, the cycle of heat absorption and heat release is realized, thereby effectively recovering the waste heat in the flue gas. In the shown working state, the left regenerator releases heat, heating the gas flowing through it, while the right regenerator absorbs heat, recovering the sensible heat in the flue gas. Through this continuous switching, the regenerator can efficiently transfer the sensible heat in the flue gas to the air or gas, significantly reducing flue gas heat loss and improving thermal utilization.

In addition, the regenerative dryer uses an induced draft fan for forced exhaust, so that the flue gas can be efficiently discharged after passing through the regenerator, and most of the flue gas waste heat is recovered. △ Composite: Single-mode burners often find it difficult to achieve efficient combustion in both high-temperature and low-temperature stages. Therefore, our company has launched a direct-fired regenerative combination baking method, allowing it to achieve optimal combustion in both high-temperature and low-temperature states. By precisely controlling the flame length and stiffness, this dryer can flexibly adapt to different baking process requirements. At the same time, it is also equipped with an advanced control system that can automatically adjust the temperature rise curve and reasonably supply the flow rate.

Refining Furnace Dryer  1. AOD Furnace Baking Refining furnace baking is more stringent than ladle baking and usually uses high-calorific gas as fuel. The AOD vertical dryer designed by Zhengzhou Zhongwei Environmental Protection Equipment Co., Ltd. is designed to bake two positions simultaneously and has dual drive functions of hydraulic motor and hydraulic cylinder, supporting equipment rotation and flipping movements.

2. RH Vacuum Tank Baking: Due to the small design of the RH vacuum tank's mouth and the relatively long tank body, it is difficult for the flame to directly contact the bottom of the tank. In conventional baking, the temperature difference between the upper and lower parts is relatively large. Our company's RH baking equipment has a unique design, with a tightly sealed furnace mouth, effectively reducing the escape of flue gas, and through the optimized design of the bottom immersion tube, ensuring the stability of the bottom baking temperature, thereby reducing the upper and lower temperature difference and improving baking efficiency.

Address: No. 118, Fengqing Road, Jinshui District, Zhengzhou City
Tel:+86-371-60960056
Mobile:+8613849187223
Email:zhongweigongyelu@126.com