Yergali Auyelkhan

Hydrate formation and erosion-related pipe wear are critical operational challenges in natural gas pipelines. This study evaluates a pyrocondensate-based liquid composition modified with fine clay particles as a dual-function formulation for apparent hydrate-onset control and erosion-wear mitigation. The liquid phase contains pyrocondensate solvent, heavy gasoline fraction, and white oil. Laboratory screening was performed for composition ranges including 60/20/20 and 65/15/20 with formulations at reported dosages of 20–25 g/1000 m³. Under the applied procedure, visible hydrate formation for model gas samples was suppressed down to −24 °C with the 60/20/20 formulation. For a field gas sample from well No. 422, the 65/15/20 formulation shifted the observed apparent hydrate-onset temperature from +6 °C to approximately −20 °C at a dosage of 20 g/1000 m³. To mitigate erosion-wear, fine clay particles were added at 10 wt.% of the liquid composition. Laboratory tests demonstrated increased visual erosion-onset time in gas–liquid–solid flows. A preliminary four-month field application on well No. 422 recorded no hydrate formation or visible erosion-related complications. The results demonstrate the empirical potential of this dual-function composition under the investigated conditions.

This study characterizes the hydrochemistry and geochemical signature of the Upper Cretaceous geothermal aquifer in the Zharkunak zone (Eastern Ili Depression, SE Kazakhstan) using certified analytical datasets from five deep wells (5539, 1-RT, 3-T, 1-TP, and 2-TP). The waters are hyperthermal (89–103 °C), alkaline (pH 8.1–9.0), and weakly mineralized (TDS 0.3–1.0 g/L), with sodium-dominated facies ranging from Na–HCO₃–SO₄ to Na–SO₄–Cl. Hydrochemical analysis indicates that water–rock interaction and cation exchange are the primary controls on fluid evolution, with limited influence from evaporation or external salinity sources. Elevated fluoride (up to ~10 mg/L) and dissolved silica (H₂SiO₃, often >50 mg/L) reflect prolonged high-temperature interaction with silicate-rich lithologies under low Ca²⁺ conditions. Trace elements and radon activity (up to 0.32 nCi/L) further support deep, fault-controlled circulation pathways. PHREEQC modeling indicates near-equilibrium to slight supersaturation with respect to silica phases, suggesting a potential risk of silica scaling during cooling, while carbonate scaling remains limited. Although the dataset is based on discharge conditions from a limited number of wells, the results demonstrate that the Zharkunak system has strong geothermal utilization potential, with management considerations related to fluoride, radon, and silica scaling. Future work should focus on integrating isotopic analyses and reactive transport modeling to better constrain subsurface processes and long-term system behavior.

Groundwater is an important source of water supply in the regions of Northern Kazakhstan. The formation and management of exploitable groundwater reserves in a given region are closely related to hydrological conditions. This article analyzes the influence of climatic factors, hydrogeological features and human activity on the formation of operational groundwater reserves in Northern Kazakhstan. The study is based on an analysis of the results of prospecting and assessment work and data from the pilot operation of the Alekseevskoye groundwater deposit in the Akmola region of the Republic of Kazakhstan.