METHOD OF OIL AND GAS CONDENSATE MULTIPAY FIELD DEVELOPMENT Russian patent published in 2014 - IPC E21B49/00 

FIELD: oil and gas industry.

SUBSTANCE: method of oil and gas condensate multipay field development includes based on the basis of seismic data and exploratory and operation drilling data identification of depths of occurrence, areas and net pays, plotting of subsurface maps, performance of detailed cross-borehole correlation with specification of boundaries for claying, bed thinning and tectonic disturbance, determination of permeability and porosity of collectors against data of standard and special experiments with core material, determination of initial pressure and temperature in the stratum against data of measurements made with a depth gage and of initial composition and properties of the hydrocarbon system saturating the stratum against results of laboratory researches of gas condensate characteristic, in process of commercial operation monitoring of the deposit development indices including measurement of bottomhole pressure and temperature, consumption rates of gaseous and liquid phases in the production system, field pipeline transfer and preparation of hydrocarbon products, performance of gas dynamic, gas condensate surveys and downwhole logging. Thereafter analysis of the development monitoring results is made, a numerical filtration model of the deposit is created on the basis of compositional approach and the model is adapted in two stages. Each of stages represents an exact algorithm excluding impact of each subsequent adaption step to results of the previous one. At the first stage material balance of hydrocarbon pseudo components is set for the deposit envisaging compliance with precise volume and mass production of the formation gas at the facility as a whole considering values of formation pressure. At the second stage the model is set for data of long-term operation of wells. At that values of bottomhole and wellhead pressure, group production of the formation gas are used as parameters for quality control of the model. Additional parameters of control include distribution of production by wells considering results of gas condensate surveys, inflow profile in compliance with bottomhole logging, values of formation pressure by wells, which are received on the basis of hydrodynamic research data. Upon adaption of the model in the above way and specification of characteristics of filtration and phase transitions in oil and gas condensate systems the model is started to calculate forecast of the development cost-performance ratio and, in result, basing on this model process modes for operation of wells, loops and gas processing facilities are defined against production levels for short-term and long-term prospects ensuring high final recovery factors of hydrocarbon products.

EFFECT: improving accuracy for determination of optimal process mode for operation of wells, loops and gas processing facilities against production levels for short-term and long-term prospects.