Open pit waste removal optimization through equipment fleet scheduling

A neighborhood search algorithm was proposed to simultaneously schedule the waste removal quantity and the equipment fleet profile over the mine life for open pit mines. An initial search domain was first defined and a good schedule was obtained as the current best schedule by searching in this domain. Then, progressively narrower neighborhood search domains were constructed around the current best schedule to search for better schedules. The objective is to minimize the present value of waste removal costs over the mine life. The resulting schedule from this algorithm provides a complete fleet profile for each year over the mine life: the selected equipment models, the number of equipment units of each model, the age of each unit, as well as the quantity of waste removed. A numerical example of application was provided to demonstrate the feasibility and merits of the algorithm.