Development of a Software Package for Modeling and Optimization of Acid Treatment Technologies in Sandstone and Carbonate Reservoirs

Flow enhancement by influencing the bottomhole zone (BHZ) makes a significant contribution to oil field development, especially in carbonate reservoirs. Improving the effectiveness of bottomhole zone treatments (BHT) is achieved by selecting effective compositions, improving the search for candidate wells and developing an optimal design. In this work we propose to consider a solution for modeling the acid treatment on the reservoir. The main idea is to improve the effectiveness of acid treatment by more accurate and comprehensive simulation of hydrodynamic and physical-chemical processes in the well and bottomhole zone, a full-fledged simulation of the properties, structure and composition of the reservoir. The software solution is a set of tools that are aimed at performing tasks related to modeling hydrodynamics during injection and production of fluid in the bottomhole zone and well, as well as modeling physical and chemical processes in the reservoir. The created tools provide simulation of non-isothermal flows of non-Newtonian fluids in the reservoir and wellbore, taking into account the heterogeneity of properties, mineralogical composition of BHZ, and distribution of contaminants in the reservoir and hydraulic fractures. The program implements a tool to correct uncertainties in the data by performing adaptation to the historical data of the well operation as well as determining the effective design when solving the optimization problem. Special attention is paid to simulation of fluid flow in tubing in order to design treatments for wells with complex design or coiled tubing (CT). The software package contains a digital database of minerals, chemical reactions, injected fluids, and includes a simulation tool for laboratory experiments. Using the developed software, the influence of geophysical and chemical model parameters on the effectiveness of the treatment, as well as the influence of secondary and tertiary reactions on the process of acid treatment in sandstone reservoirs was studied. The influence of the characteristics of formation damages on the effectiveness of the treatment, and the flow of non-Newtonian fluid (diverters, emulsion compositions, etc.) in the well and reservoir was studied. The analysis of acid treatments on several assets of oil companies was carried out. These examples show the main scenarios of work with the program: evaluation of additional production and economic effect, adaptation and adjustment of the model to the fact, selection of the optimal design. The simulator includes both a simplified 2D model and a complex 3D model with varying degrees of detail when setting initial parameters (mineralogy, geometry) and when calculating dynamic characteristics. An important addition is the user-friendly of the interface for different levels of users.