Improving the Milling Efficiency in a HPGR Ball Mill Circuit, Case Study: Plant No. 2 Follad Sirjan Iranian

Authors

1 M.Sc Graduated, Dept. of Mining Engineering, Sirjan Islamic Azad University, Sirjan

2 Assistant Professor, Dept. of Mining Engineering, Sirjan Islamic Azad University, Sirjan

Abstract

Comminution circuit in concentrator No 2 at Follad Sirjan Iranian consists of a high pressure grinding rolls (HPGR) mill working in a closed circuit with a wet screen. The undersize from the screen enters a ball mill which works in a closed circuit with a hydrocyclone and MIMS. In this circuit, a ball mill with the diameter of 5.5 m fed by three hydrocyclones in a closed circuit is employed. In this research, the enhancement of the efficiency of comminution circuit was investigated by improving the efficiency of the grinding circuit. Therefore, the effect of mill feed rate on the grade and particle size of final concentrate was studied. Furthermore, the impact of power draw on the concentrate particle size was investigated. For this purpose, K80 and blain number were used to quantify the particle size. Moreover, a new approach based on mass balance was employed to estimate the mill feed flow rate. Results indicated that the hydrocyclone overflow particle size and the final concentrate particle size reduced while increasing the mill feed rate. Eventually, it was found that particle size of final concentrate was reduced while increasing the mill power draw.

Keywords


[1]     Bearman, R. (2006). “High-Pressure Grinding Rolls Characterising and Defining Process. In: Advances in Comminution, K.S. Kawatra (Ed.), SME, 15-39.
[2]     Tavares, L. M. (2005). “Particle weakening in high-pressure roll grinding. Minerals Engineering, 18(7): 651-657.
[3]     Wills, B. A., and Finch, J. A. (2016). Mineral processing technology”. Butterworth-Heinemann, 123-146 .
[4]     Yaghoobi,.M , and Rahmani, F.(2016) . “Comprehensive application of roller presses in worldwide mineral industries”.Second International Conference on Science and Engineering, Istanbul-Turkey, 1-14.
[5]     آزماینده، م.؛ ریاحی مدوار، ع.؛ 1394؛  "مروری بر آسیای غلتکی فشار بالا و تاثیر آن در فراوری مواد معدنی". کنفرانس بین المللی علوم و مهندسی، دبی، امارات متحده عربی، ص 20-12.
[6]     بارانی،ک.؛ بلوچی، ح.؛ 1393؛ "مقایسه استفاده از سنگ شکن غلطکی فشار بالا و روش های معمول سنگ شکنی بر روی سینتیک خردایش آسیای گلوله ای سنگ آهن". پنجمین کنفرانس مهندسی معدن، تهران، ایران، ص 9-1.
[7]     Ballantyne, G. R., Hilden, M., and van der Meer, F. P. (2018). “Improved characterisation of ball milling energy requirements for HPGR products. Minerals Engineering, 116: 72-81.
[8]     Shi, F. N., and Napier-Munn, T. J. (2002). “Effects of slurry rheology on industrial grinding performance. International Journal of Mineral Processing, 65(3): 125-140.
[9]     ارغوانی، ا.؛ حجتی، ا.؛ بنیسی؛ 1394؛ "کاهش میزان گوگرد کنسانتره با بهبود کارآیی مدار آسیا تر کارخانه فرآوری مجتمع سنگ آهن گل‌گهر". نشریه علمی پژوهشی مهندسی معدن، دوره بیست و هفتم، شماره 10، ص 61-67.
[10]  Harun, N. Y., and Afzal, M. T. (2016). “Effect of Particle Size on Mechanical Properties of Pellets Made from Biomass Blends”. Procedia Engineering, 148: 93-99.
[11]  Pal, J., Ghorai, S., Agarwal, S., Nandi, B., Chakraborty, T., Das, G., and Prakash, S. (2015). “Effect of Blaine Fineness on the Quality of Hematite Iron Ore Pellets for Blast Furnace. Mineral Processing and Extractieve Metallurgy Review, 36(2): 83-91.
[12]  ASTM, (2007). “Standard test methods for fineness of hydraulic cement by air-permeability apparatus”. Book of Standards Volume: 04.01.