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Show 1 Development of swirl burner series for steel making processes * •• .* .* by Yutaka Suzuki,Kotofuai Kaminaka,Katuhiko Kaburagi,Iunihiro Yabuki Synopsis At"Sumitomo Metals. we have developed several high efficiency burners using various fuels. The six main types are. 1) a SNT burner which produces a strong swirl flame. 2) a SSF burner which produces a bright stable flame when using pulverized coal. 3) a SSC burner producing a variable length flame with extremely low NOx emission, 4) a SCF burner producing a variable length curtain flame. 5) a SLG burner which produces a stable flame when using lean gases. and 6) a SNM burner which produces a reducing and direct heating flame in continuous heat treatment furnaces. The purpose of this paper is to present details on the structure and combustion characteristics of these burners and to ' outline their use in our factory. 1 . Introduction A variety of burners are used in heating and heat treatment processes at steel works. There are many kinds of fuels ~sed for burners; these include coke oven gas (COG). blast furnace gas (BFG). converter gas. LPG and LNG as gas fuel. light oil. heavy oil and coal tar as liquid fuels. and pulverized coal as a solid fuel. We have made great efforts to select the most economical fuel for each spe~ific use. At Sumitomo Metals. we have conducted the reformation and development of burners for a long time from the position of a user of these kinds of fuels. As a result, we have developed low NOx burners showing excellent operability and thermal efficiency, making a great contribution to energy savings. In this report, we will give an outline of the structure, characteristics. combustion characteristics and application records of a series of burners we have developed. 2. Kinds of Burner The different kinds of burners we have developed and the characteristics and application purposes of each are shown in Table 1 and Figure 1 respectively. Our SNT burner is a compact and widely used low NOx burner characterized by a strong swirl and nar~ow tile for combusition air. Our SSF burner is a two stage pulverized fuel burner developed from the SNT burner. This SSF burner is excellent in combustion stability and shows excellent combustion characteristics with either heavy oil or solid fuel. Our SSC burner is a twostage type burner developed from our SSF burner to reduce of NOx and control flame temperature distribution. It is an ultra low NOx burner with a changeable flame length. Our SCF burner was developed from our SSC burner for the sinter ignition furnaces, and it produces a curtain flame with excellent in-line heating performance. Our SLG burner was developed for low calorie gas stable combustion. It is able to burn blast furnace gas (650 kcal/Nm3). Lastly, our SNM burner heat steel strip rapidly with a reducing and direct heating flame. It is able to heat steel strip up to 850°C without oxidation in continuous heat treatment furnaces. Since these burners are nozzle-mixed type burners, they show excellent stability and are characterized by the following features: * Sumitomo Metal Industries,Ltd ** Sumikin Management CO., Inc. |