Technological and environmental features of the well construction cycle in mineral leaching methods

Purpose. Development of rational regulations for cleaning and securing wells for underground leaching of metals while simultaneously complying with environmental safety standards. Research methodology. Determination of the features of well construction was carried out using theoretical and experimental research methods, instrumentation and materials. The measurement of technological parameters of flushing liquids was carried out using special devices: an SPV-5 viscometer, a SNZ-2 rotational plastometer, a VM-6 device. Research results.We have proposed formulations of washing liquids with a reduced solid phase content. For these liquids, the optimal concentrations of the clay component, which is within 5%, have been determined. Using carboxymethylcellulose as an example, the effectiveness of chemical treatment is achieved at concentrations of this polymer of up to 0.3%. Additional enhancement of the stabilization of clay washing liquids can be obtained by using water-repellent reagents, in particular sulfate soap with a concentration of up to 2%. The reagents studied, among other things, have a moderately insignificant impact on the environment. Originality. We have proven and analytically studied the possibility of increasing the efficiency and environmental friendliness of the method of underground leaching of metals by rationalizing the technology for constructing production wells, in particular, by using high-quality flushing fluids with the appropriate values of conditional viscosity and static shear stress, as well as fluid loss. Practical implications. The washing liquid formulations proposed for use are distinguished by the availability of components and clear predictability of technological characteristics; their use will allow to avoid the phenomena of deterioration of the properties of the well waterproofing system while simultaneously ensuring compliance with environmental protection standards.