PRODUCTION IMPROVEMENT FROM NATURALLY FRACTURED OIL RESERVOIR USING MULTILATERAL WELLS

摘要

Naturally fractured reservoir give the most important part of oil and gas reserves and production in the world. More than 40% oil and gas reserves exist in naturally fracture reservoir that have a large productivity. Characteristic of this reservoir is unique, because there are two fluid flow mechanisms in reservoir. Reservoir fluid flows to the matrix the fracture and then flows to well. Modeling of naturally fractured reservoir in this study is using Warren and Root model with dual porosity model. In this study reservoirs have two porosity and two permeability that are matrix and fracture.Results of core laboratory and well test analysis indicate that the X field is a naturally fracture reservoir. Characterization of naturally fractured reservoir at X field from well test yield omega and lambda, which is the most important parameter to characterize the naturally fracture reservoir. There are two well in the X field X-1 and X-2.The objective of this study is to predict and analyze oil recovery at X field using the application of multilateral well. Modeling naturally fractures reservoir with reservoir simulator is conducted to determine the performance of oil productivity in the wells. By analyzing few branches and length of lateral section of the well can predict the optimum oil productivity in the X field.The result of simulation for horizontal well, dual horizontal wells and multi branches well indicates that dual horizontal wells yield the most large of oil recovery than the others. Horizontal well with longer lateral section than the dual horizontal and multi branches well with the same lateral section with the dual horizontal apparently do not yield a large oil recovery.After analysing the effect of lateral length penetration to a few branches, now study is focusing on the effect of characteristic of omega and lambda to design multilateral well. Omega is indicated as fluid storage of matrix and fracture, meanwhile the lambda is the inter porosity flow of matrix to the fracture. There are three parameters those will be discussed such as porosity fracture, fracture spacing and permeability fracture. These three parameters are very important in influence the design of multilateral well.