Mathematical Modeling of the Differential Sticking Coefficient of Clay Drilling Fluids

Document Type : Research Paper

Authors

1 Mechanical Engineering Academic Unit, Petroleum Engineering, Federal University of Campina Grande, Brazil

2 PPG-CEMat, Center of Science and Technology, Federal University of Campina Grande, Brazil

Abstract

The main objective of this work is to propose a mathematical model for the differential sticking coefficient of clayey drilling fluids with a lubricant as an additive and evaluate the influence of differential pressure and lubricant content on filter cake thickness and permeability. Tests were carried out on fluids composed of water and 4.86% of active bentonite clay prepared in Hamilton Beach agitators at a high rotation speed (17000 rpm) for 20 minutes. After a 24-hour time-out in a closed container, lubricants were added to the fluids at different levels. To obtain the differential sticking coefficient (DSC), and the filter cake, a differential sticking tester by Fann with a spherical torque plate was used, and the filter cake thickness was determined in an extensometer. The setting time, differential pressure, and lubricant content were defined as the input variables (independent variables) to the DSC mathematical model. The differential pressure and lubricant rate were the independent variables to the mathematical model of filter cake thickness (FCT) and permeability (K), which varied according to a factorial planning, was known as a second order model. The experimental data regression was performed utilizing Statistic software, version 7.0. The results clearly showed that it was possible to obtain a statistically meaningful and predictive mathematical model for DSC. It was also observed that the increase in the lubricant content was responsible for a DSC value reduction due to the fact that the lubricant was a dispersing agent reducing the filtrate volume and the filter cake thickness, and thereby decreasing the sticking risk due to differential pressure. Finally, from the analysis of point values and response surfaces for FCT and K, it was possible to observe tendencies that made clear that the differential pressure and lubricant content influenced filter cake properties.

Keywords


      [1]     Medeiros B. E. A., Barros Neto E. L. E., and Neto A. A. D., “Efeito de Viscosificantes e Redutores de Filtrados na Filtração de Fluidos de Perfuração à Base Agua,” Plano de Trabalho de Pesquia, 2008.##
      [2]     Darley H. C. H. and Gray G. R. “Composition and Properties of Drilling and Completion Fluids,” (5th ed.), Houston, Texas, Gulf Publishing Company, 1988.##
      [3]     Thomas J. E., “Fundamentos da Engenharia de Petróleo,” Editora Interciência, Rio de Janeiro, 2001.##
      [4]     Miura K., Guilherme I. R., Morooka C. K., and Mendes J. R. P., “Processing Technica Daily Reports in Offshore Petroleum Engineering-an Experience,” Journal Advance Computational Intelligence and Intelligent Informatics, 2003,7, 223-228.##
      [5]     Reid P. I., Meeten G. H., Way P. W., Clark P., et al., “Mechanisms of Differential Sticking and a Simple Well Site Test for Monitoring and Optimizing Drilling Mud Properties,” SPE 22549, New Orleans, Louisiana, 1991.##
      [6]     Simon K., Gaurina-Medimurec N., and Pasic B., “Drilling Fluid Differencial Sticking Tendency,” Rudarsko-geološko-naftni Zbornik, UDC 622.244.442, Zagreb 2005, 17, 31-35.##
            [7]            Pereira E., Uso de Inibidores de Argilas Como Solução de Problemas em Sondagem., Disponível em: <http//:www.systemmud.com.br, Acesso em: 28 dez, 2010.##
      [8]     Reid P. I., Meeten G. H., Way P.W., Clark P., et al., “Differential-sticking Mechanisms and a Simple Wellsite Fest for Monitoring and Optimizing Drilling Mud Properties,” SPE 64114, SPE Drilling & Completion, 2000.##
      [9]     Krol D. A., “Additives Cut Differential Pressure Sticking in Drillpipe,” Oil & Gás Journal Technology, 1984, 82, 55-59.##
    [10]    Isambourg P., Ottesen S., Benaissa S., and Marti J., “Down-hole Simulation Cell for Measurement of Lubricity and Differential Pressure Sticking,” SPE/IADC 52816, 1999.##
    [11]    Kelessidis V. C., Tsamantaki C., Pasadakis N., Repouskou E., et al., “Permeability, Porosity and Surface Characteristics of Filter Cakes from Water-bentonit Suspensions,” WIT Transactions on Engineering Sciences, 2007, 56, 173-182.##
         [12]         Courteille J. M. and Zurdo C., “A New Approach to Differential Sticking,” paper SPE 14244, SPE Annual Technical Conference, Las Vegas, 1985, 22-25.##
    [13]    Byck H. T., The Effect of Formation Permeability on the Plastering Behavior of Mud Fluids,” API Drilling Production Practice, New York, 1940, 40-44.##
    [14]    Krumbien W. C. and Monk G. D., “Permeability as a Function of the Size Parameters of Unconsolidated Sand,” Transactions of the AIME, 1943, 151, 153-163.##
    [15]    Bradley W. B., Jarman D., Plott R. S., Wood R. D., et al., “A Task Force Approach to Reducing Stuck Pipe Costs,” IADC/SPE 21999, IADC/SPE Drilling Conference, Amsterdam, 1991.##
    [16]    Santos H., “Differentially Stuck Pipe: Early Diagnostic and Solution,” SPE/IADC 59127, IADC/SPE Drilling Conference, New Orleans, Louisiana, 2000.##
    [17]    Nascimento R. C. A. M., Amorim L. V., Lira D. S., and Lira H. L.,Revista Eletrônica de Materiais e Processos,” O Fenômeno de Prisão Diferencial: Uma revisão da Literatura, 2010.##
    [18]    Farias K. V., Amorim L. V., Ferreira H. C., and Pereira E., “Estudo da Reologia e Espessura do Reboco de Fluidos de Perfuração: Influência de Dispersantes e Umectante Aniônicos” Revista Cerâmica, 2006, 52, 307-314.##
 
    [19]    Reid P. I., Meeten G. H., Way P. W., and Clark P., et al., “Mechanisms of Differential Sticking and a Simple Wellsite Test for Monitoring and Optimizing Drilling Mud Properties,” SPE/IADC 35100, New Orleans, Louisiana, 1996.##