Kazakhstan journal for oil & gas industry

The relevance of this work is caused by the need to reduce operating costs in the group of companies of NC «KazMunayGas» JSC in general and in «Ozenmunaigas» JSC in particular by increasing the service life of the tubing used. In this regard, the purpose of research and testing was to select the optimal tubing material for each group of wells. Correct grouping of wells (PSL – zoning) is also important for the selection of the optimal tubing material. The article indicates the methodology and characteristics for the distribution of wells into groups (PSL – zoning). analysis of the causes (wiping, corrosion) contributing to the rapid wear of tubing in the fields of JSC Ozenmunaigas, and recommendations for their solution.

The article presents the main geological reasons for the emergence of problems with the waterflooding efficiency at Karazhanbas field, as well as an overview of the main methods used to increase the coverage of its productive formations by development: periodic injection of steam and water into the formation, alignment of the injectivity profiles of injection wells, as well as gel-polymer flooding used in the neighboring field confined to the same productive formations. The results of a differential analysis of the development indicators of individual objects of this field are described with the aim of selecting areas of influence in them using the indicated methods. The article describes the results of the analysis of the effectiveness of the application of the WFP method of injection wells in the selected areas of this field.

The process of tar thermal cracking in a mixture with crushed oil shale to obtain components of motor fuels and raw materials for the process of thermal cracking is investigated in this paper. The optimization results of technological parameters (shale concentration, temperature, and duration) are presented and the material balance (mass.%) of the process is made. It was found that during single-stage processing under relatively mild conditions (5 MPa, 425°C, feed space velocity of 1.0 h-1), a deep destruction of tar is achieved (the yield of the gasoline fraction from boiling point to 200°C is ~12 wt.%; medium distillates with boil. point 200–370°C-43-44 mass.%; raw materials for thermal cracking with boil. point above 370°C ~15-16 wt.% on per the original tar). The generating coke-like products and the V and Ni contained in the raw materials are deposited on the mineral part of the shale and removed from the reaction zone with the liquid products of the process.

Nowadays, it is especially important and relevant to improve the efficiency of existing methods of enhanced oil recovery, in particular, thermal methods using water steam. The use of catalysis at the stage of development of unconventional hydrocarbon fields, namely super-viscous and bituminous oils, will allow solving this problem. This work is devoted to the study of the transformation of heavy oil from the Ashalchinskoye field in the process of catalytic aquathermolysis. The oil samples were extracts from sandstone, which was subjected to thermal steam treatment in a high-pressure reactor at temperatures of 200 and 250°C for 24 h. Nanosized iron (II, III) oxide in complex with a hydrogen donor was used as a catalytic composition. According to the results of SARA-analysis, it was found that at a temperature of 200°C, iron oxide does not show its catalytic properties, and there is no noticeable improvement in the composition of heavy oil. The destruction of resins and asphaltenes is observed after thermocatalytic treatment at 250°C. This leads to the enrichment of oil with lighter hydrocarbons, which is confirmed by GC-MS data of the saturated fraction of oil. All this provides a significant decrease in the viscosity of heavy oil compared to the non-catalytic process from 1140 cP to 37 cP The formation of coke-like substances adsorbed on sandstone as a result of thermocatalytic action at 250°C was revealed by the results of TG-DSC.

This paper discusses the boundary values of the reservoir properties of carbonate rocks of the Triassic sediments of South Mangyshlak, which are important for the interpretation of production geophysical data and for perforating and blasting operations.

In terms of lithological composition, Triassic deposits are represented by two types of commercial reservoirs – terrigenous and carbonate. Carbonate reservoirs are localized in the volcanic-dolomite and volcanic-limestone strata of the Middle Triassic. These rocks are characterized by a complex type of reservoir: porous-fractured, porous-cavernous and fractured. Sediments of the Upper Triassic occur with erosion on the Middle Triassic sedimentary complex and are represented by alternating tuffaceous, silt-sandy and mudstone rocks. Polymictic sandstones are oil-saturated to varying degrees; oil deposits are confined to them.

To substantiate the quantitative criteria of the reservoir, the results obtained during special laboratory studies of the core were used. Filtration studies were carried out, where physical and hydrodynamic characteristics were determined when oil was displaced by displacing reagents. The obtained parameters were used to construct correlations “collector – non-collector”. Using the relationships between the reservoir properties of the reservoir, the dependence of the porosity and permeability on the residual water content, as well as open porosity and permeability on the dynamic porosity, the boundary values were determined.