Improved drilling and reservoir penetration efficiency is directly related to the quality of the drilling mud used. The right choice of mud type and its components will preserve formation productivity, stability of the well walls and reduce the probability of other complications. Oil and gas operators use barite, less often siderite or hematite weighting agent as a weighting component in the composition of drilling muds for the conditions of increased pressure. But the use of these additives for the penetration of the productive formation leads to the reduction of filtration characteristics of the reservoir, as it is almost impossible to remove them from the pore channels. Therefore, barite-free drilling mud of increased density based on formic acid salts with the addition of carbonate weighting agent as an acid-soluble bridging agent is proposed. The results of experimental investigations on rheological parameters of barite-free solutions are given and the obtained data are analyzed. Based on the comparison of results it is recommended to use high-density drilling mud on the basis of formic acid salts (sodium and potassium formate) and with the addition of partially hydrolyzed polyacrylamide with molecular mass of 27 million.
The importance of hydrocarbon resources and the oil and gas industry is currently difficult to overestimate. About one third of the world’s natural gas reserves are concentrated on the territory of the Russian Federation; in terms of oil reserves Russia is second only to five states, but even this is enough to develop and improve this branch of production. The Strategy for the Development of the Mineral Resource Base of the Russian Federation until 2035 outlines promising directions for economic modernization. They include rational use of the created mineral resource base by means of engaging hard-to-recover oil and gas reserves and undeveloped solid mineral deposits, reducing the negative impact of subsoil development on the environment, qualitative improvement of the information support system for subsoil use, monitoring and control over the development of the mineral resource base of the Russian Federation by developing information technologies. This requires, among other things, introduction of automated management and regulation systems in the field of geology and subsoil use, as well as systems for processing, interpretation, storage and provision of geological data to subsoil users.
Article presents investigations on the development of a drilling mud composition for directional wells in an oil field located in the Republic of Tatarstan (Russia). Various rheological models of fluid flow and their applicability for drilling muds are analyzed. Laboratory experiments to measure the main rheological parameters of a solution, such as plastic viscosity, dynamic shear stress, as well as indicators of non-linearity and consistency are presented. On the basis of laboratory investigations, it was concluded that high molecular weight polymer reagents (for example, xanthan gum) can give tangible pseudoplastic properties to the washing fluid, and their combination with a linear high molecular weight polymer (for example, polyacrylamide) reduces the value of dynamic shear stress. Thus, when selecting polymer reagents for treating drilling muds at directional drilling, it is necessary to take into account their structure, molecular weight and properties. Combination of different types of reagents in the composition of the drilling mud can lead to a synergistic effect and increase the efficiency of the drilling process as a whole.
The paper considers variants of lightweight cement compositions with additives of various substances, such as clay components, ash systems, silica additives, kerogen, gilsonite, microspheres, as well as the process of cement slurry aeration. Recommendations on the use of compositions in different conditions are presented. A decrease in the density of the solution is achieved not only due to the low density of the materials used, but also as a result of an increase in the water-cement ratio. In such conditions, it is not possible to ensure the formation of a durable and impermeable cement stone in the well, which creates high quality inter-reservoir insulation. The characteristics of the physical and mechanical properties of existing lightening additives are given, which allows determining the most rational conditions for the use of cement slurries for improvement of the well cementing quality.
The article deals with ways of rock weakening for efficiency increase of hard rocks drilling, also development of drilling fluid composition is considered. Aim of the project is to develop drilling fluid composition which increases efficiency of hard rocks destruction. Authors conducted experimental investigation of drilling fluid composition development and their main structural rheological and filter characteristics. Influence of various solutions, including developed one, on hard rocks destruction process is evaluated on introduced testing bench. Investigation results indicate that composition and characteristics of developed drilling fluid positively influence hard rocks destruction process. Implementation of clayless drilling fluid with anion-active surfactant composition additives allows boost of drilling operations performance by increase in mechanical velocity of drilling and drill meterage per bit.
The article deals with the problems of complex power supply of the well construction process in adverse climatic conditions. An option of associated petroleum gas utilization in power units for drilling operations is offered. The method of calculating heat losses of technological objects and required heating capacity for maintaining working temperature is given. A combined heat and power scheme enabling simultaneous electric and heat supply of oilfield objects with the use of associated petroleum gas as an energy source for power generation units is developed. Implementation of such a scheme guarantees power structure functioning without downfalls of produced en-ergy during the year, thus maintaining high efficiency of overall power generation.
