The paper describes the introduction and estimation of performance criteria for the gelling agent injection technology based on a general approach to modeling physical and chemical enhanced oil recovery (EOR) methods. The current mathematical models do not include performance criteria for the process of gelling agent injection and do not allow for assessing the level of success of a treatment job in production wells. The paper introduces such criteria for the first time. To simulate the effect on injection wells, the mass conservation laws and the generalized flow law are used, and closing relations for the gelling rate are taken into account. A conformance control coefficient is introduced which characterizes the positive effect of well treatments and injectivity drop which characterizes the negative effect. The performance criteria allow for identifying the wells where the treatment jobs were the most successful. The model verification, based on the comparison of post-treatment injectivity estimated in the developed model, with Rosneft’s field data showed a satisfactory match. The developed correlations can be used as the basis for a surrogate model that allows for avoiding building sector geological and flow simulation models of the treated zone.

Paper presents multi-fractured horizontals performance analysis in case of low-permeable formation. The puppose of the analysis is to suggest a method of optimizing multi-frac parameters (such as number of fracs, fracs spacing, Xf etc.) in different geological conditions. Paper describes an algorithm of estimating main formation and well characteristics and forecasting future production. In addition, an approach to multi-frac design optimization for new wells is shown.The main tools of well performance analysis are production logging, well testing, decline analysis and simulation. Authors have performed all these survey types analyzing multi-fractured wells behavior. Authors have developed and successfully implemented of Company fileds new technologies of testing and production logging on such wells. Active development and massive implementation of permanent data gauges systems (PDG) let Company to use decline analysis methods of well performance. A lot of data obtained has led to new interpretation theories development, allowing to explain wells behavior and match pressure and rate data. For more robust estimation of parameters, production logging was performed with use of modern tool with arrays of sensors.With the results obtained, series of one-layer model calculations was performed, resulting in optimal multi-frac design for one of the fields being studied.

The paper describes the use of pressure monitoring of producing and injecting wells for estimating the effectiveness of pressure maintenance system (PMS). On the first stage of forming such system, due to low replacement rate there is no traditional signs of effectiveness: producing rates increase, bottomhole pressures raise etc. In this case decline analysis based on permanent telemetric downhole gauge system, can be effective estimation tool. The authors have proved the effectiveness of pressure maintenance system on one of the oil fields of Orenburg region. Basing on pressure and rate analysis, hydrodynamic models were built in Ecrin software of Kappa Engineering of producing wells, placed right next to injection wells. Results of long-term well tests and decline analysis were the base of estimation approach. Based on complex analysis of producing wells, placed near first injection clusters, paper shows the stable influence of injection. Solving of this problem would be impossible without developing an online well parameters monitoring system on the field. The use of stationary telemetric system helps solving problems not only in wells or clusters scale, but also for the whole field. This work again proved the effectiveness of equipping wells with telemetric monitoring systems of all parameters. It provides the possibility to make fast and effective decisions of field development and maintain base production rates. The work shows significant value of hydrodynamic development monitoring as for specific wells and for the whole field.

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