New Hydrocarbon Reservoir Sweet Spot Identifier Enabling Optimal Field Development Plans

摘要

To attain an optimum field development plan in hydrocarbon reservoirs,well placement can be a cumbersome and time-consuming task.A major reason for this is the lack of a sweet spot identification system to direct the process of placing wells in optimum locations.In this article,a novel method is presented for identifying sweet spots in hydrocarbon reservoirs.A new tool devised from this method is able to identify potential well locations,thereby enhancing optimum field development and maximizing field economic recovery.The developed tool,the optimal reservoir productivity index(OPTIMA-two patents;one granted’and one pending2),is an innovative parallel simulation-based algorithm for generating an accurate reservoir dynamic productivity index(PI)with efficient high performance computation utilization,which guides decision making in well placement,and field development and management.OPTIMA reduces the computational expense of reservoir simulation,especially for large models by’targeting only specific grid cells based on cutoffs of porosity,permeability,and fluid saturations.The tool runs the evaluation based on a set of production control constraints and the duration of the well productivity evaluation.It generates several simulation runs and calculates a time-dependent 4-dimensional array of layer productivity indices for each grid cell in the model.OPTIMA combines the results of the different simulation cases into a 3-dimensional(3D)property array based on calculated values of the total dynamic PI.The 3D property,once loaded into a post-processor,can be used to define an area of interest to evaluate different well types and configurations.To optimize well placement,the use of static parameters utilization alone is not sufficient since the reservoir reaction is dynamic once the wells start producing.OPTIMA enables robust and speedy evaluation of sweet spots in hydrocarbon reservoirs while capturing reservoir complexity and heterogeneity.The main advantage of OPTIMA is that it calculates the contribution of each grid cell to the well PI based on dynamic parameters that implicitly combine fluid and rock properties with pressure and saturation as they change with time.This ensures that both static and dynamic reservoir parameters are considered in the process of identifying sweet spots.When compared with conventional methods,OPTIMA surpasses in terms of extending the production plateau and maximizing recovery on a field level performance.This article introduces OPTIMA to identify sweet spots in green and brown fields,which can be used to generate sweet spot maps in a very short time.In fact,the integration of OPTIMA with a reservoir simulator provides a unique opportunity for reservoir engineers to quickly analyze their fields,evaluate the sweet spots,and optimize a field development plan to maximize ultimate recovery of hydrocarbons.