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Reservoir Formation Damage Episode 3 Part 6

Tham khảo tài liệu 'reservoir formation damage episode 3 part 6', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Part VI Formation Damage Models for Field Applications Fluids and Solids Invasion Sand Production and Scale Formation Chapter 18 Drilling Mud Filtrate and Solids Invasion and Mudcake Formation Summary Near wellbore mud filtrate and fines invasion during drilling operations and the resulting formation damage and filtercake formation are amongst the most important problems involving the petroleum reservoir exploitation. This chapter reviews the fundamental processes and their mathematical formulation necessary to develop models that can be used for assessment of the damaged zone filtrate and fines concentrations fluid saturations and the filtercake thickness and permeability alteration during drilling. The effects of under and over balance drilling on near wellbore formation damage are discussed. The models for simulation of the single and two-phase flow situations in the formation with water or oil based drilling mud cases are described. External particle invasion prior to filtercake buildup and its effect on the formation damage by particle invasion and retention and filtercake formation are described. These models are demonstrated by various applications. The models presented here can be used for accurate estimation of the near wellbore fluid saturations and resistivity profiles which are necessary for accurate welllog interpretation. Introduction As illustrated in Figure 18-1 by Yao and Holditch 1993 drilling of wells into subsurface reservoirs is usually accompanied with mud circulation in order to remove the frictional heat generated as the drill bit penetrates the rock to provide a lubrication for reduction of the frictional 608 Drilling Mud Filtrate and Solids Invasion and Mudcake Formation 609 Figure 18-1. Mud filtrate invasion in the near-wellbore formation after Yao and Holditch 1993 SPE reprinted by permission of the Society of Petroleum Engineers . effects and to transport the cuttings of the rock produced during drilling. However mud fines and filtrates