اصلاح طراحی آسترهای دیواره ورودی و خروجی در آسیاهای خشک نیمه خودشکن مجتمع معدنی گل گهر

حسنخویی, علیرضا; مالکی مقدم, مصطفی; ارغوانی, احسان; حاجی زاده, امیر; برزگر, محمد ابراهیم; بنیسی, صمد

doi:10.30479/jmre.2019.11235.1292

اصلاح طراحی آسترهای دیواره ورودی و خروجی در آسیاهای خشک نیمه خودشکن مجتمع معدنی گل گهر

نوع مقاله : علمی-پژوهشی

نویسندگان

¹ دانشجوی دکتری، مرکز تحقیقات کاشی گر، دانشگاه شهید باهنر، کرمان

² استاد فرآوری مواد معدنی، گروه مهندسی معدن، دانشگاه ولی عصر (عج)، رفسنجان

³ کارشناسی ارشد فرآوری مواد معدنی، مرکز تحقیقات کاشی گر، کرمان

⁴ کارشناسی ارشد فرآوری مواد معدنی، شرکت معدنی و صنعتی گل گهر، کرمان

⁵ کارشناسی ارشد فرآوری مواد معدنی، شرکت گهر روش، سیرجان، کرمان

⁶ استاد، گروه مهندسی معدنی، دانشکده فنی، دانشگاه شهید باهنر، کرمان

10.30479/jmre.2019.11235.1292

چکیده

تاثیر آسترهای دیواره آسیاهای نیمه خودشکن خشک شرکت معدنی و صنعتی گل‎‎گهر بر حرکت بار درون آسیا و عملکرد خردایش مورد بررسی قرار گرفت. نتایج دست‌آمده منجر به ارایه و نصب طرح جدیدی از این آسترها در آسیاهای کارخانه شد. در کارخانه فرآوری مگنتیت گل‌گهر برای خردایش اولیه سنگ معدن آهن، سه عدد آسیای نیمه‌خودشکن خشک (متر2_/5×متر9) به‎صورت موازی به‌کار گرفته شده است. آزمایش‌های انجام شده در یک آسیای مدل کوچک مقیاس‌شده (قطر 1 متر) نشان‌داد که آسترهای متفرق‌کننده در این آسیاها لزوما بهترین شرایط خردایش را فراهم نمی‌کنند. به‌همین دلیل، یک طرح جدید که در آن از آسترهای کم‌ارتفاع‌تر به همراه آسترهای شعاعی استفاده شد، مورد بررسی قرار گرفت. به‎منظور درک نحوه رفتار مواد داخل آسیا، مشاهدات حاصل از آزمایش در آسیای مدل، شبیه‎سازی‌های انجام شده توسط نرم‎افزار KMPC_DEM و اطلاعات جمع‎آوری شده از آسیای صنعتی استفاده شد. نتایج نشان‎ داد که آستر جدید با ارتفاع کم به همراه آسترهای شعاعی (با ارتفاع 14_/5 سانتی‎متر در مقیاس صنعتی)، در محدوده افت فشار مجاز درون آسیا (45-40 میلی‎بار)، کارایی خردایش را افزایش داد. در طرح جدید در هر قطاع، تعداد آسترها از 5 به 4 و ضخامت آسترهای متفرق‎کننده درونی از 45 به 30 سانتی‎متر کاهش یافت‎ و آستر متفرق‎کننده بیرونی با آسترهای شعاعی جایگزین شد. این کار باعث افزایش فاصله بین آسترهای دیواره ورودی و خروجی(طول موثر)آسیا به میزان 53 درصد شد. در طرح جدید، وزن و حجم آسترهای دیواره به‎ترتیب به میزان9 و23 درصد کاهش یافت. با نصب آسترهای جدید، تناژ ورودی از 441 به 465 تن‎برساعت افزایش یافت، عمر آسترها نیز بین 50 تا 200 بهبود پیدا کرد و زمان تعویض آنها به میزان 5_.37 درصد کمتر شد.

کلیدواژه‌ها

موضوعات

فرآوری مواد معدنی

عنوان مقاله [English]

Improvement in Designing Dry SAG Mills End Liners - Proposed for Gol-E-Gohar Mine

نویسندگان [English]

A. Hasankhoei ¹
M. Maleki-Moghaddam ²
E. Arghavani ³
A. Haji-Zadeh ⁴
M.E. Barzgar ⁵
S. Banisi ⁶

¹ P.hD. Student, Kashigar Mineral Processing Research Center, Shahid Bahonar University of Kerman, Kerman, Iran

² Professor, Mineral Processing Group, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran

³ M.Sc, Kashigar Mineral Processing Research Center, Shahid Bahonar University of Kerman, Kerman, Iran

⁴ M.Sc, Gol-E-Gohar Mining and Industrial Company, Sirjan, Iran

⁵ M.Sc, Gohar-Ravesh Company, Sirjan, Iran

⁶ Professor, Dept. of Mining Engineering, Shahid Bahonar University of Kerman, Kerman, Iran

چکیده [English]

The effect of shell liners on mill performance has been the subject of various studies, but little known about the effect of dry SAG mills end liners on throughput and grinding efficiency. In particular, in the case of dry Aerofall mill types where it has been claimed that the end liners play a key role in the crushing and grinding actions. This paper experimentally characterizes the role of end liners in dry SAG mills with the objective of obtaining a thorough understanding of the effects of end liners design on the load trajectory and SAG mill performance. It was thought the characterization study will lead to design new end liners which eliminate or reduce the shortcomings of the current liners and improve the comminution efficiency mainly by prolonging liner life. The test works conducted in a scale down mill with a diameter of 1m indicated that conventionally used "deflector" type liners did not provide efficient environment for grinding. Direct observations obtained from the model mill during tests by various visualization techniques, along with simulations using the KMPCDEM software were the main sources of understanding flow behavior of charge inside the mill. In this research, to improve the grinding efficiency, a new design using low profile end liners incorporating radial ribs of proper height was investigated. The special design of model mill made it possible to increase the radial ribs height in steps of 6mm up to 18.5mm. The transparent end of the mill enabled accurate trajectory determination by image analysis. The results indicated that the new lower height profile deflectors and 15.5mm-height (14.5cm in industrial scale) radial ribs improved the mill performance while avoiding excessive pressure drop across the mill and wear on the liner. The image analysis showed that the use of new liners increased the distribution of coarse particles across the mill cross section from 28% to 35%. A new liner design was proposed by decreasing the number of liners in each slice from 5 to 4 pieces. The thickness of the inner head liners reduced from 45cm to 30cm and the outer deflector liners replaced by14.5 cm radial ribs. The distance between the feed and discharge liners increased from the original 115cm to 176cm which increased the effective length of the mill by 53%. The new design reduced the weight and volume of end liners by 9% and 23%, respectively. On account of installation of the new liners in Aerofall SAG mills the throughput increased from 441 to 465 t/h, the product size decreased from 519 to 480 μm and the amount of recycled material from the SAG mill product decreased from 10 to 6%. The most significant improvement was observed in the liner life; an increase of 50 to 200 % in liner life depending on the location of end liners was achieved. The relining time also reduced by 37.5% with the new liners.

کلیدواژه‌ها [English]

AG/SAG mill
Feed end liners
Discharge end liners
Gol-E-Gohar
Simulation
DEM

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