Injection Lance Research Articles

Combustion Behavior of Pulverized Coal in Tuyere Zone of Blast Furnace and Influence of Injection Lance Arrangement on Combustibility.

Hot model experiments on pulverized coal injection were carried out to understand the combustion mechanism of pulverized coal injected into the blast furnace. The combustion behavior of the pulverized coal was directly observed by a high speed camera, and the temperature distribution of combustion flame was analyzed by an image processor. According to the results, the combustion flame was not uniform across the cross section of the blow pipe and tuyere, and the fluctuation of the flame was observed. Then, it was found that the dispersion of the pulverized coal had a great role on combustibility owing to the rapid consumption of oxygen by the combustion of volatile matter. Moreover, it was confirmed that the arrangement of injection lance influenced on the combustion efficiency, since the dispersion of coal particles was enhanced by the double lance arrangement. On the basis of the above results, the dispersion of coal particles was analyzed by the calculation of the average distance of individual coal particles to easily evaluate the effect of the injection lance on combustibility.

高炉羽口部における微粉炭燃焼挙動と燃焼性に及ぼす吹き込みランス配置の影響

Hot model experiments on pulverized coal injection were carried out to understand the combustion mechanism of pulverized coal injected into the blast furnace. The combustion behavior of the pulverized coal was directly observed by a high speed camera, and the temperature distribution of combustion flame was analyzed by an image processor. According to the results, the combustion flame was not uniform across the cross section of the blow pipe and tuyere, and the fluctuation of the flame was observed. Then, it was found that the dispersion of the pulverized coal had a great role on combustibility owing to the rapid consumption of oxygen by the combustion of volatile matter. Moreover, it was confirmed that the arrangement of injection lance influenced on the combustion efficiency, since the dispersion of coal particles was enhanced by the double lance arrangement. On the basis of the above results, the dispersion of coal particles was analyzed by the calculation of the average distance of individual coal particles to easily evaluate the effect of the injection lance on combustibility.

Experimental study of the effect of gas injection parameters on the bath mixing intensity induced during steelmaking

The present study is concerned with the evaluation of the bath‐mixing intensity induced by gas injection during steelmaking. The rate constant for the process of mass transfer between the two cold‐model simulated immiscible liquids (water/oil) is employed as the criterion of judgement of bath‐mixing intensity. Gas is either injected from the bottom alone or simultaneously from top and bottom. Bath‐mixing criterion is successfully correlated with the mixing power. Increase in bottom injection rate is found to increase the rate constant. In the simultaneous injection lance distance, and top and bottom gas‐injection rates are shown to be the relevent independent dynamic parameters. From the comparison of the rate constants between pure bottom and simultaneous injection and pure top and simultaneous injection, it is asserted that the simultaneous injection provides more operational flexibility, better control of slag formation and refining rates as per blow requirements and steel grades. However, some minimum gas is required to realize the operational benefits.

Cleaning flue gases from an open-hearth furnace when the bath is blown with oxygen

To develop recommendations on the cleaning of process gases to satisfy health standards, the Magnitogorsk Metallurgical Combine conducted studies of dust and gas emissions from two 400-ton open-hearth furnaces operated by the ore-and-scrap process with subsurface and combination blowing of the bath by oxygen. Oxygen was injected through the combination lateral burners into the flame during cold-charging and heating. Different variants of overhead and subsurface injection lances were evaluated. The results show that the traditional types of gas cleaning (high-pressure Venturi tubes, electrostatic precipitators) can be used with the introduction of the proposed methods of intensifying open-hearth steelmaking with oxygen.

Hydrodynamic modeling of some gas injection procedures in ladle metallurgy operations

Experimental studies of flows generated in a 0.30 scale water model of a 150 ton steelmaking ladle are reported. These were used to test the adequacy of a generalized two-dimensional computational scheme for predicting flows generated by fully submerged and partially submerged gas injection lances. The roles of turbulence models and grid configuration were assessed. Predictions for flow fields generated in a 150 ton steelworks ladle with and without tapered side walls, and with and without surface baffles around the rising plume were considered.