1دانشجوی دکتری، فراوری مواد معدنی، دانشکده مهندسی معدن و متالورژی، دانشگاه یزد
2دانشیار، فراوری مواد معدنی، دانشکده مهندسی معدن و متالورژی، دانشگاه یزد
3هیات علمی پژوهشی، بخش شیمی و مهندسی شیمی، دانشگاه چالمرز، گوتنبرگ، سوئد
تاریخ دریافت: 26 شهریور 1397،
تاریخ بازنگری: 15 مهر 1397،
تاریخ پذیرش: 21 آذر 1397
چکیده
بازیابی کلی سلول فلوتاسیون به بازیابی ناحیه پالپ و ناحیه کف بستگی دارد. از جمله عوامل اثرگذار بر بازیابی ناحیه کف، زمان ماند کف است که رابطه عکس با بازیابی کف و بازیابی کلی فلوتاسیون دارد. از سوی دیگر زمان ماند کف به آهنگ هوادهی سلول فلوتاسیون و عمق کف وابسته است. آهنگ هوادهی در سلول‌های هوادهی شده، پارامتری مستقل است اما در سلول‌های خودهواده به متغیرهای مختلفی از جمله عمق کف بستگی دارد، بنابراین تنظیم آن پیچیده‌تر و دشوارتر از سلول‌های هوادهی شده است. از اینرو در این تحقیق تلاش شده است تا تاثیر عمق کف و آهنگ هوادهی بر سرعت ظاهری گاز، زمان ماند کف و کارآیی متالورژیکی سلول فلوتاسیون (بازیابی جرمی کنسانتره و نسبت غنی‌شدگی) بررسی شود. با آشکار شدن ارتباط بین این پارامترها و محدودیت‌های تنظیم عمق کف و آهنگ هوادهی، دانش بیشتر با هدف بهره‌برداری مناسب‌تر از این نوع سلول‌ها فراهم می‌شود.آزمایش‌ها در یک سلول فلوتاسیون خودهواده 50 متر مکعبی در کارخانه کنسانتره شماره 6 سنگ آهن گل گهر سیرجان انجام شد. نتایج نشان داد که تغییرات عمق کف اگر چه سبب تغییر آهنگ هوادهی شد اما تغییرات آهنگ هوادهی اثر قابل ملاحظه‌ای بر زمان ماند کف و در نتیجه کارآیی متالورژیکی سلول فلوتاسیون نداشت. همچنین در این نوع سلول‌ها، عمق کف گزینه مناسبی برای تغییر آهنگ هوادهی و سرعت ظاهری گاز نیست زیرا محدوده تغییرات سرعت ظاهری گاز با تغییرات عمق کف در مقیاس صنعتی، کم بود.
The effects of gas rate and froth depth on flotation performance of an industrial self-aerated cell
نویسندگان [English]
H. Naghavi1؛ A. Dehghani2؛ M. Karimi3
1Ph.D Student, Dept. of Mining and Metallurgical Engineering, Yazd University, Yazd
2Associate Professor, Dept. of Mining and Metallurgical Engineering, Yazd University, Yazd
3Postdoctoral Research, Dept. of Chemistry and Chemical Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
چکیده [English]
The overall flotation recovery depends on the recovery in the pulp zone as well as recovery in the froth zone. The froth retention time affects the froth recovery and it has an inverse relationship with both froth recovery and overall recovery. On the other hand, the froth retention time depends on gas rate and froth depth. The gas rate is an independent factor in induced-air flotation machines, whereas in self-aerated cells it depends on various variables and the froth depth is one of them with significant effect. Therefore, adjusting the gas rate is more complicated and more difficult in the induced-air flotation machine. This study attempts to investigate the effects of froth depth and gas rate on superficial gas velocity, froth retention time and metallurgical performance of the cell. The operation of these types of cells can be improved, by understanding the relationship between these parameters particularity the adjustment of froth depth and gas rate. Experimental tests were carried out in a 50 m3 self-aerated cell in Gol Gohar iron ore processing plant. The results showed that although the froth depth variations, changed the gas rate, but the gas rate variations did not have a significant effect on the froth retention time and the metallurgical performance. Also, the froth depth was not a good option to change the gas rate and the superficial gas velocity in this type of flotation cells, because the range of superficial gas velocity variations was low when the froth depth was changed in industrial-scale.
کلیدواژه ها [English]
Self-aerated flotation cell, froth depth, gas rate, superficial gas velocity, froth retention time
مراجع
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