Modeling of filtration and mudcake buildup: An experimental investigation

This paper presents an experimental investigation and modeling of filtration and mudcake buildup during wellbore drilling. Extensive studies have been performed on this topic over the past seven decades and their general findings are summarized. In particular, the filtration model proposed in Dewan and Chenevert (2001) is discussed along with recommended methods for determining the model's parameters. New static filtration data were obtained using permeable filter discs manufactured from sand-cement mixtures to generate controlled formation material. The experimental results, consisting of fluid loss vs. time, mudcake porosity, and thickness at the end of the test, were used to evaluate the validity of the proposed methods and investigate the model's ability to predict the actual mudcake properties. Using the experimental results, some limitations of this model were identified. Therefore, modifications to Dewan and Chenevert's model were suggested to allow it to better capture the measured data, leading to the development of a new Wider Windows Filtration Model. Last, the effects of differential pressure, solids content of the mud, and filtration control agent on filtration and mudcake properties are presented and discussed.