Cement Manufacturers Association

27 The steps involved are as under Figure 1 Optimization procedure as outlined in the text. Inputs to different process blocks are also indicated. a) Know the deposit In this step, a Deposit Block Model is prepared using an updated version of the 3D topographical survey of the deposit. This model is based on actual exploration done in the field area and analysis of sample data and is a digital representation of the deposit and its inventory (Fig 2). Thus, the overall exercise of optimisation and mine planning depends primarily on the authenticity and accuracy of said sample data and its interpretation. Using the above deposit block model is imperative for understanding the inventory in terms of quality and quantity available in the deposit. To do so, one prepares Grade-Tonnage curves from these block models, which provide details of deposit inventory at various cut-off grades. This helps to understand the deposit better for planning purposes. One may also use such models as a basis for mine scheduling with alternative choices. b) To Optimise and schedule This step puts various constraints on the above Block model (like mining constraints, Raw mix design, resources & equipment availability, water table, habitants, applicable laws for mining, etc). This is essential for preparation of mine scheduling and optimisation model, which should remain workable for the complete lifetime of the mine. Such optimisation of the deposit helps in understanding potentiality of deposit, where after putting constraints and quality variations together, the reserves are maximised (as much as possible) and wastage is minimised. Extensive and versatile sensitivity analysis is also done during optimisation for deciding in favour of a sustainable strategy. c) To divide Optimisation in various schedules Optimisation model is divided into short term and long-term schedules. Short term planning may be yearly to monthly to weekly etc. In terms of long- term strategy, one requires action to be delivered in a phase wise manner, and the development of a sustainable production plan with desired quality and quantity. Such plans should consider various options to build flexibility in the optimization process, to correspond with the changing market scenario, the latest industry practices for limestone working, and current expert knowledge on technology. One should also undertake medium level planning on a yearly basis (important for yearly business plans). This also becomes essential for adjusting mining parameters and plant requirements with regard to resource optimisation demands. Preparation of multiple plans based on seasonal variations is a must for all such medium level planning. Survey Assay Data Deposit Block Model Mining Constraints Current extract knowledge and technology Changing market scenario Latest Industry practices Optimi- -sation Long term planning Yearly planning Quarterly planning Monthly planning Blast Hole Model Weekly Planning Products Schedule with Extract plans Feedback Blast Hole Input Blasting Blast Hole Planning Machine Planning Equipment Optimisatic Pile Parameter Raw Mix Block Model updation (based on Feed Back data)