بهینه‌سازی همزمان عیارحد و ظرفیت کارخانه‌ی فرآوری با لحاظ کردن عدم قطعیت قیمت

نوع مقاله: پژوهشی

نویسندگان

1 دانشگاه تربیت مدرس

2 دانشگاه تهران

چکیده

عیار حد و ظرفیت تولید دو متغیر مؤثر در طراحی و مطالعات امکان‌سنجی پروژه های معدنی می‌باشد و محاسبه و بهینه سازی آن ها نقش مهمّی در اقتصاد عملیات معدنکاری ایفا می‌کند. برای تعیین و بهینه کردن عیار حد کوشش های بسیاری صورت گرفته است که بارزترین آنها الگوریتم Lane است. هدف این تحقیق بهینه‌سازی هم‌زمان عیار حد و ظرفیت تولید کارخانه‌ی فرآوری با لحاظ کردن عدم‌قطعیت قیمت است. برای این کار با اعمال تغییراتی جزئی در الگوریتم Lane و صورت‌بندی آن در قالب یک مسئله‌ی برنامه‌ریزی غیرخطی، مدلی طرّاحی شد که قابلیت بهینه‌سازی همزمان دو متغیر پیش‌گفته را دارد. برای لحاظ کردن عدم قطعیت قیمت از روشی ابتکاری مشابه روش مدل‌سازی براونی هندسی بهره گرفته و عملکرد مدل با استفاده از داده‌های یک معدن فرضی مس به کمک افزونه‌ی Solver در نرم افزار Excel ارزیابی شد. بر اساس نتایج به‌دست آمده، ظرفیت پیشنهادی کارخانه در بازه‌ی 16 تا 17، با میانگین 5/16 میلیون تن در سال می‌باشد. این بازه بر عیار حد بهینه‌ی 17/0 تا 2/0، با میانگین 19/0 درصد انطباق دارد و ارزش خالص فعلی نیز بین 900 تا 1200با میانگین 1080 میلیون دلار است. توزیع ظرفیت بهینه‌ی کارخانه‌ی فرآوری اندکی چولگی منفی و توزیع عیار حد بهینه اندکی چولگی مثبت از خود نشان می‌دهند، و توزیع ارزش خالص فعلی بیشینه تقریباً متقارن و نرمال است

کلیدواژه‌ها


عنوان مقاله [English]

Simultaneous optimization of cut-off grade and capacity of mineral processing plant

نویسندگان [English]

  • Farzam Saffariyan 1
  • Ahmadreza Sayadi 1
  • Aliasghar Khodayari 2
چکیده [English]

Cut-off grade and capacity of processing plant are two factors influencing the design and the feasibility study of mine and calculation of these two plays an important role in mining economy. The main purpose of this study is to optimize the cut of grade and production capacity considering price uncertainty, simultaneously. Slight changes on lane algorithm and its formulation as a nonlinear programming problem were done, leading to design a model that can optimize the both factors simultaneously. A heuristic model similar to geometric Brownian model has been used to consider uncertainty in the model. An assumed copper mine data were used to model verification. Solver plugin in excel for model solving was used. Finally, the recommended values for plant’s capacity were in range of between 16 and 17 with mean value of 16.5 million tons. This value for cut of grade is between 0.17 to 0.2 with the mean value of 0.19 percent, and for net present value is between 900 to 1200 with the mean value of 1080 million dollars. The optimum capacity distribution of processing plant has slight negative skewness, optimum cut of grade distribution has slight positive skewness and approximately maximum net present value has normal distribution.

کلیدواژه‌ها [English]

  • Optimization
  • Cut-off grade
  • Mineral Processing plant capacity
  • Price uncertainty
  • Lane algorithm
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