Quality assessment of carbonate raw materials and cut off parameters for reserves estimation for domestic deposits

Abstract

The article systematizes the main industrial types, use directions and the supply degree of carbonate raw materials, among which the most scarce are raw materials as flux and for the cement and sugar industries. Available reserves within the accessible territory do not provide a sufficient period of operation of industrial enterprises for more than 10-15 years. Taking into account the time, which is at least 3-5 years, for the deposits exploration and development, the most effective way of providing reserves is to review the objects that are being developed today in other areas of use (except metallurgical raw materials and the sugar industry) to allocate part of the reserves, which may be suitable for these deficient uses. The analysis and systematization of the cut-off parameters for the reserves calculation of various types of carbonate rocks in accordance with their industrial types and the requirements of geological and economic evaluation were carried out. A list of 25 carbonate rocks objects was evaluated, which were analyzed according to the main indicators of productivity, availability of reserves and their quality. The basic parameters for calculating the reserves are compliance with the quality of the use direction, the depth of the reserves calculation, the minimum thickness of the layers from 2 m, as well as the limit coefficient of overburden in the range of 12-13 m³/t, which determines the maximum depth of development by the open method. The determined cut-off quality parameters: Ca + MgO grade 50.5-53.5%; grade of MgO is not more than 3.5-10%; grade of SiO₂ is no more than 1.5-3%; sulfur content – no more than 0.06-0.15%; phosphorus content – no more than 0.01-0.06%; among the indicators of physical and mechanical properties (compressive strength) – by less than 30-50 MPa. This direction of revaluation is an effective way to increase the explored reserves of carbonate raw materials, which does not require as much time and investment as exploration and preparation for the industrial development of new deposits.

Keywords

• carbonate rocks
• cut-off parameters
• limestone quality
• flux raw materials
• reserves and resources