Well productivity decline have been widely observed in Western Desert, Egypt for oil and gas wells producing the reservoir fines. The phenomenon has been explained by the lifting, migration and subsequent plugging of the pores by the fine particles, finally resulting in permeability decrease. It has been observed in numerous core flood tests and field cases.
This extensive work deals with the subject of formation damage by drilling fluids. It discusses the impact of damage on well productivity, the major mechanisms of formation damage by drilling fluids, assessment and testing of damage, outline considerations for mud selection and optimization, and removal of mud damage.
Work in progress in oil companies, service companies and academic institutions will continue to improve our knowledge, which in turn will increase the efficiency with which we produce oil and gas.
Laboratory core flood tests had been used to determine the causes, degree, and extent of damage. Scanning electron microscopy (SEM) was used to analyze the rock samples used for the core flood test before and after the test. Core flood test had been done to evaluate the effect of acid on damaged cores. Matrix acid stimulation on a case study from the studied field was evaluated. In this work, the authors will suggest some unique solutions to mitigate formation damage using Nano-materials with especial emphasis on formation damage caused by drilling fluid which lead to clay swilling problem