Journal articleOpen access
Methods for determining hydrodynamic parameters at hydrogenic stratal deposits mined by in-situ leaching
Методы определения гидродинамических параметров на гидрогенных пластовых месторождениях, отрабатываемых способом ПВ
- Navoi State University of Mining and Technologies, Navoi, Uzbekistan
Highlights
- Pumping tests: 6–8 days, at the preliminary or detailed exploration stage.
- Discharge kept constant within ±10%; the measuring vessel should take at least 1 minute to fill.
- Levels read at 3, 5 and 10 minutes after the start, then with each discharge reading, about three times a day once the level has steadied.
- Temperature measured at the wellhead, at the bottom and sometimes along the whole well.
Abstract
In the process of prospecting and exploration of hydrogenous deposits enclosed in loose sedimentary rocks, as well as their development by the method of in-situ leaching, it becomes necessary to obtain a whole range of initial hydrogeological data for the design of in-situ leaching enterprises, as well as for the qualitative conduct of the process and the economic feasibility of their working off. The most important hydrodynamic parameters in this case are: coefficients of filtration, water conductivity, piezo conductivity and level conductivity, productivity and injectivity of wells, as well as the magnitude of the radius of influence and the hydraulic relationship of the productive formation with other aquifers.
English abstract from the paper. The authors’ abstract, reproduced under CC BY-NC 4.0.
In plain English
Pumping tests lasting 6–8 days are run at the preliminary or detailed exploration stage to obtain the data for designing pilot and pilot-industrial in-situ leaching plants. They give the effective thickness of the productive aquifer and its hydraulic conductivity, transmissivity and diffusivity and how these change across the deposit and with depth; its water yield, well productivity, radius of influence and drawdown; the hydraulic link with the aquifers above and below; the static level, or the initial formation pressure in flowing wells, and the direction and gradient of flow; and the chemistry, mineralisation, pH, Eh, temperature and suspended solids of the water.
Tests pump single wells, one well watched from observation wells (cluster tests) or several interacting wells at once; each productive aquifer is tested separately. Water is lifted by submersible pumps or air-lifts; a two-string air-lift lets the dynamic level be read through its inner pipe. Before a test the water in the well is replaced with formation water and the static level, formation temperature and well depth are measured. The discharge is kept constant within ±10%, or raised in steps where the rock around the screen is unstable. Discharge is measured by volume, levels at 3, 5 and 10 minutes and then with each discharge reading, and the temperature of the water at the wellhead, at the bottom and sometimes along the whole well. Levels of acid leaching solutions are corrected for their density.
After each test the recovery of the level is followed in the pumping and observation wells, and drawdown and recovery curves on a semi-logarithmic scale give the hydraulic conductivity, transmissivity and diffusivity. The authors note that such field work builds a hydrogeological database for managing the underground leaching process.
How to cite
S. B. Khamidov, N. M. Karimov, G. B. Bakoeva and D. Z. Mansurova (2022). Methods for determining hydrodynamic parameters at hydrogenic stratal deposits mined by in-situ leaching. Journal of Advances in Engineering Technology, 2022, No. 4 (8), pp. 22–24. https://sciencealgorithm.uz/?portfolio=%D0%BC%D0%B5%D1%82%D0%BE%D0%B4%D1%8B-%D0%BE%D0%BF%D1%80%D0%B5%D0%B4%D0%B5%D0%BB%D0%B5%D0%BD%D0%B8%D1%8F-%D0%B3%D0%B8%D0%B4%D1%80%D0%BE%D0%B4%D0%B8%D0%BD%D0%B0%D0%BC%D0%B8%D1%87%D0%B5%D1%81%D0%BA%D0%B8