@article { author = {Farzanegan, A and ebtedaei, A}, title = {Closed Circuit Simulation of SAG Mill and Hydrocyclone Units at Aghdarreh Gold Plant}, journal = {Journal of Mining Engineering}, volume = {6}, number = {13}, pages = {67-78}, year = {2012}, publisher = {Iranian Society of Mining Engineering (IRSME)}, issn = {1735-7616}, eissn = {2676-4482}, doi = {}, abstract = {The run-of-mine ore of Aghdarreh gold mine is comminuted through crushing and grinding stages to achieve the required degree of liberation of gold particles. The comminution circuit consists of a SAG mill equipped with a discharge trommel and a hydrocyclone package which is operated in closed circuit with the SAG mill. The hydrocyclone package, is used to classify the particles ground by the SAG mill. The overflow of hydrocyclone package is fed to the gold recovery circuit at downstream. Gold extraction is carried out by leaching process and cyanidation within the stirred tanks. In this research, optimization study of the grinding circuit of Aghdarreh gold processing plant was done by modeling and simulation using MODSIM software to reduce P80 of the closed SAG circuit to less than 70 microns in order to increase the degree of liberation of gold particles at the same current circuit capacity. Plant sampling campaigns were scheduled to determine the required parameters of SAG mill model, i.e., breakage distribution function, selection function, calibrating Plitt's model and validation of models. Breakage distribution function was defined by the MODSIM software based on t10 vs. ECS model parameters (A and b) and abrasion parameter (ta) provided by the user. Selection function was also defined by the simulation software based on the given Austin model parameters (a, α, μ and Λ). Two plant surveys were done to collect the samples from various grinding circuit streams. In both sampling surveys, incremental sampling from all circuit streams including trommel undersize and oversize (ore scats), hydrocyclone feed, underflow and overflow were done at steady state for a time period of two hours. The SAG mill fresh feed was also sampled by temporarily stopping the conveyor belt and collecting enough ore material from a cut with two meters length. Operating conditions during the sampling were recorded based on the control room readings. The final sample for each stream was prepared by combining the incremental samples taken every ten minutes. Particles size distribution and solid percent of all samples, except SAG mill feed, were determined in the laboratory and then balanced by NorBal data reconciliation software. The balanced particle size distributions and flow rates were used in the MODSIM software for models’ calibration and subsequent simulations. After validating the calibrated Plitt's model based on the second sampling survey, circuit simulations were done for internal overflow and underflow diameters equal to 82 and 70 mm, respectively, six hydrocyclones in operation, increasing the charge volume from 21 to 35 % and increasing the ball charge volume from 10 to 12 %. Based on the mentioned input data, the prediction showed that P80 of the circuit product can be reduced to approximately 51 microns. .}, keywords = {Grinding circuits,Comminution modeling and simulation,Optimization of SAG mills,Aghdarreh gold plant}, title_fa = {شبیه‌سازی مدار بسته آسیای نیمه‌خودشکن و هیدروسیکلون کارخانه فرآوری طلای آق‌دره}, abstract_fa = {  کانسنگ استخراجی از معدن طلای آق‌دره به منظور آزادسازی ذرات حاوی فلز طلا، نخست تحت فرآیندهای سنگ‌شکنی و آسیاکنی در کارخانه فرآوری قرار می‌گیرد. سپس، ذرات خرد شده با استفاده از یک خوشه هیدروسیکلون‌ در مدار بسته با آسیای نیمه‌خودشکن طبقه‌بندی می‌شوند و به‌دنبال‌آن استحصال طلا با روش فروشویی و سیانوراسیون داخل مخازن همزن‌دار انجام می‌گیرد. در این تحقیق بهینه‌سازی مدار خردایش این کارخانه، با هدف کاهش ابعاد محصول نهایی  (p80)به کمتر از 70 میکرون برای افزایش درجه آزادی ذرات طلادار با ظرفیت موجود و با رویکرد توجه به فرآیند فروشویی با روش مدلسازی و شبیه‌سازی توسط نرم‌افزار MODSIM™ انجام شد. جریان‌های مختلف مدار خردایش در دو مرحله و در وضعیت یکنواخت عملیات نمونه‌برداری شدند. نخست، داده‌های توزیع اندازه ذره نمونه‌های جمع‌آوری شده به منظور مدلسازی دقیق‌تر مدار، موازنه جرم شدند. سپس از نرم‌افزار MODSIM، برای کالیبراسیون مدل‌ها و شبیه‌سازی مدار استفاده شد. پس از اعتبارسنجی مدل کالیبره شده پلیت در محیط MODSIM‌، شبیه‌سازی مدار خردایش با قطر داخلی سرریز و قطر داخلی ته‌ریز به‌ترتیب با اندازه‌های 82 و 70 میلیمتر، با تعداد 6 سیکلون در حال کار و افزایش درصد حجمی بار داخل آسیای نیمه‌خودشکن از 21 درصد به 35 درصد با حجم بار گلوله 10 تا 12 درصد، انجام شد که نشان می‌دهد  (p80) محصول آسیاکنی قابل کاهش به حدود ۵۱ میکرون می‌باشد.  }, keywords_fa = {مدارهای آسیاکنی,مدلسازی و شبیه‌سازی خردایش,بهینه‌سازی آسیاهای نیمه‌خودشکن,کارخانه طلای آق‌دره}, url = {https://ijme.iranjournals.ir/article_1363.html}, eprint = {https://ijme.iranjournals.ir/article_1363_c0039d77f58ae9930dfbb63402f151bf.pdf} }