Аналіз розвитку технологій задувки доменних печей в 20-21 століттях

Abstract

The article discusses the trends and classification of blast furnace blowers over the past 100 years. The development of blower technology is divided into 3 periods: The 1st period lasted until the end of the 30s of the XX century, characterized by a lack of scientific knowledge, mysticism and based on previous experience; the 2nd period - until the early 70s, when the "traditional" blower technology was mastered with one problem - difficulties with opening the first releases and simultaneous overheating of the top; the 3rd period continues today, it includes the development of new methods for intensifying heat transfer during blowing and scientific generalization of blower techniques. The main tasks of blowdown are to bring the blast furnace back to normal operation in a short time, in compliance with safety rules, without significant costs, and to preserve the blast furnace and auxiliary equipment for long-term productive operation. These tasks are closely linked to the design features of blast furnaces, including the cooling system, lining type and furnace size, which have steadily increased from less than 500 m3 to 5,600 m3. The complexity of understanding the processes of heating the charge column during the blowing period with the formation of a gas flow and a cohesion zone in it is the reason for numerous discussions about rational blowing methods: methods for calculating and placing layers of the blast furnace charge, the use of various hot blast additives (nitrogen, natural, blast furnace or coke oven gas, oxygen, steam, etc.), the rate of increase in hot blast flow and its temperature, the trend of pressure drop along the height of the charge column. The use of wood in the blast charge, the installation of constrictor rings in air tuyeres or the closure of a part of the tuyeres for blowing are discussed. Recommendations for blast furnace blowers are given. A comparison of "traditional" blowing with "progressive" blowing and blowing with nitrogen developed at the Iron and Steel Institute National Academy of Sciences of Ukraine are presented.