A method for roasting lime using blast furnace gas in a sleeve lime kiln

Abstract

The invention belongs to the technical field of lime kiln roasting and relates to a method for solving the problem that a sleeve lime kiln cannot active lime with low-calorific-value gas, in particular to a method for roasting lime with blast furnace gas in the sleeve lime kiln. According to the method, driving air for injection in an injector is replaced with low-calorific-value blast furnace gas, an injection effect is realized, conditions that low-calorific-value gas combustion temperature cannot meet the lime roasting requirement and driving air causes excessive combustion-supporting wind are eliminated, and the sleeve kiln is more energy-saving. Other parameters are optimized and configured, the method can effectively use the low-calorific-value blast furnace gas to roast lime in the sleeve kiln, the lime quality can be guaranteed, and the lime production cost can be reduced.

Description

technical field [0001] The invention belongs to the technical field of lime kiln roasting, and in particular relates to a method for solving the problem that a sleeve lime kiln cannot use low calorific value gas to roast active lime, specifically a method for using blast furnace gas to roast lime in a sleeve lime kiln. Background technique [0002] With the continuous promotion of the application of the sleeve type lime shaft kiln in the steel and chemical industry, the full negative pressure operation and simple production process of the production process have been recognized by the majority of lime production units. The calorific value of the fuel used requires converter gas or mixed gas with a calorific value of about 7740 kJ. If the calorific value is too low, qualified products cannot be produced even if the output is reduced. However, due to the continuous development of circular economy in the iron and steel industry, there are good ways to use gas with a calorific v...

AI Technical Summary

Problems solved by technology

[0008] There are many gases involved in the combustion in the lower combustion chamber of the sleeve kiln, mainly including: the combustion air provided by the burner 7, the lime cooling air injected by the injector 4, the driving air in the injector 9, and the flue gas in the parallel flow section 3, while the fuel is only the mixed gas provided by the burner 10, see figure 1 , taking a sleeve kiln with a daily output of 500 tons of lime as an example, after its normal production reaches full load, the lower combustion chamber needs about 8,000 cubic meters of gas with a calorific value of about 7,740 kJ per hour, and the combustion air is respectively: lime cooling The air is 12,000 cubic meters, the driving air is 7,000 cubic meters, and the combustion-supporting air provided by the burner is 4,000 cubic meters. Therefore, the amount of air participating in the combustion in the lower row reaches 23,000 cubic meters. Since the main component of converter gas is carbon monoxide, accounting for 60% ~70%, the theoretical air demand for carbon monoxide is 2.381, the excess air in the lower combustion chamber is nearly 7,000, which should cause a large waste of energy, and because the driving air in the injector directly determines the amount of circulating gas used for co-current calcination , if it is necessary to further improve the lime production and quality, it is necessary to increase the amount of driving air, so that there will be more excess air, which will further fail to meet reasonable combustion conditions and cause greater energy waste. Therefore, this problem is the current sleeve kiln lime The contradiction between calcination process and combustion energy-saving control cannot be solved by optimizing parameters

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