石油天然气工程标准手册第二卷.pdf

STANDARD WILLIAM C. LYONS EDITOR MEB X D 2 1 F STANDARD HANDBOOK OF Engineering STANDARD HANDBOOK OF Engineering WILLIAM C. LYONS, PH.D., P.E. EDITOR Gulf Professional Publishing an imprint of Butternorth-Heinemann STANDARD HANDBOOK OF ROLEUM GAS Engineering Copyright 0 1996 by Butterworth-Heinemann. All rights reserved. Printed in the United States of America. This book, or parts thereof, may not be reproduced in any without permission of the publisher. Originally published by Gulf Publishing Company, Houston, TX. 10 9 8 7 6 5 4 3 2 For ination, please contact Manager of Special Sales Butterworth-Heinemann 225 Wildwood Avenue Tel 78 1-904-2500 Fax 781-904-2620 For ination on all Butterworth-Heinemann publications available, contact our World Wide Web home page at Library of Congress Cataloging-in-Publication Data Wobu, MA 01801-2041 Standard handbook of petroleum and natural gas engineering / [edited by William Lyons]. p. cm. Includes bibliographical references and index. ISBN 0-88415-642-7 Vol. l, ISBN 0-88415-643-5 cV01.2 1. Petroleum engineering. 2. Natural gas. I. Lyons, William William C. TN870.S6233 1996 665.5-dc20 96- 13965 CIP ISBN 0-88415-643-5 Printed on Acid-Free Paper - iV Contributing Authors .................................................. vii Preface ........................................................................... ix 5-Reservoir Engineering ............................................ 1 Basic Principles, Definitions, and Data, 3 ation uation, 86 Pressure Transient Testing of Oil and Gas Wells, 214 Mechanisms and Recovery of Hydrocarbons by Natural Means, 225 Material Balance and Volumetric Analysis, 228 Decline-Curve Analysis, 244 Reserve Estimates, 249 Secondary Recovery, 259 Fluid Movement in Waterflooded Reservoirs, 269 Estimating Waterflood Residual Oil Saturation, 30 1 Enhanced Oil Recovery s, 319 References, 344 6-Production Engineering ..................................... 363 Properties of Hydrocarbon Mixtures, 365 Flow of Fluids, 426 Natural Flow Perance, 533 Artificial Lift s, 594 Stimulation and Remedial Operations, 664 Surface Oil Production Systems, 702 Gas Production Engineering, 754 Corrosion and Scaling, 889 Environmental Considerations, 939 Offshore Operations, 964 References, 971 7-Petroleum Economics ......... , .... , ........ , ................ 985 Estimating Oil and Gas Reserves, 987 Classification of Petroleum Products, 989 s for Estimating Reserves, 990 Non-Associated Gas Reservoirs, 99’7 Production Stimulation, 1004 Determining the Value of Future Production, 1010 The Market for Petroleum, 1010 Economics and the Petroleum Engineer, 1012 Preparation of a Cash Flow, 1012 Valuation of Oil and Gas Properties, 1023 Risk Analysis, 1025 References, 1030 Appendix Units and Conversions SI ............... 1035 Index .......................................................................... 1049 Contributing Authors Robert 4. Col it P.G. Consultant in Ecology and Geophysics Socorro, New Mexico Micheal J. Economides, Ph.D. Texas A all those many individuals that assisted in the typing and other duties that are so necessary for the prepara- tion of original manuscripts; and all the families of the authors that had to put up with weekends and weeknights of writing. The editor would especially like to thank the group of individuals that assisted through the years in the overall organization and preparation of the original written manuscripts and the accompanying graphics, namely; Ann Gardner, Britta Larrson, Linda Sperling, Ann Irby, Anne Cate, Rita Case, and Georgia Eaton. All the authors and their editor know that this work is not perfect. But we also know that this handbook had to be written. Our greatest hope is that we have given those that will follow us, in future editions of this handbook, sound basic material to work with. William C. Lyons, Ph.D., P.E. Socorro, New Mexico X STANDARD HANDBOOK OF Engineering 5 Reservoir Engineering F. David Martin New Mexico Institute of Mining and Technology Socorro, New Mexico Robert M. Colpitts, P.G. Consultant, Geology and Geophysics Socorro, New Mexico Basic Principles, Definitions, and Data .................................................... 3 Reservoir Fluids 3. Fluid Viscosities 7. ation Volume Factors 12. Fluid Compressibilities 20. Estimating Fluid Properties Using Computers 27. Properties of Fluid-Containing Rocks 35. Porosity 33. Pore Volume 35. Permeability 36. Capacity 38. Transmissibility 38. Resistivity and Electrical Conductivity 38. Rock Compressibility 49. Properties of Rocks Containing Multiple Fluids 32. Total Reservoir Compressibility 52. Resistivity Index 53. Surface and Interfacial Tension 58. Wettability and Contact Angle 61. Capillary Pressure 68. Effective Permeabilities 72. Relative Permeabilities 76. Effect of Wettability on Fluid Rock Properties 79. ation uation ............................................................................. 86 Coring and Core Analysis 86. Drill Stem Tests 108. Logging 109. Influences on Logs 118. Openhole Logs and Interpretation 122. Determination of Initial Oil and Gas in Place 208. Productivity Index 210. Pressure Transient Testing of Oil and Gas Wells ................................. 214 Mechanisms and Recovery of Hydrocarbons by Natural Means .......... 225 Definitions and Concepts 214. Important Pressure Transient Analysis Equations 222. Petroleum Reservoir Definitions 225. Natural Gas Reservoirs 225. Primary Recovery of Crude Oil 225. Primary Recovery Factors in Solution-Gas-Drive Reservoirs 228. Material Balance and Volumetric Analysis ........................................... 228 Material Balance for Gas Reservoirs 231. Material Balance Equations in Oil or Combination Reservoirs 233. Generalized Material Balance Equation 234. Material Balance for Solution- Gas-Drive Reservoirs 237. Predicting Primary Recovery in Solution-Gas-Drive Reservoirs 238. Predicting Primary Recovery in Water-Drive Reservoirs 240. Volumetric Calculations for Recovery of Gas and Oil 241. Decline-Curve Analysis ......................................................................... 244 Exponential Decline 246. Hyperbolic Decline 247. Harmonic Decline 248. Production Type Curves 248. Reserve Estimates ................................................................................. 249 Definition and Classification of Reserves 249. s of Estimating Reserves 254. Quality of Reserve Estimates 258. Secondary Recovery .............................................................................. 259 Fluid Movement in Waterflooded Reservoirs ....................................... 269 Definitions 259. Gas Injection 260. Water Injection 262. Spacing of Wells and Well Patterns 262. Displacement Mechanisms 269. Viscous Fingering 275. Mobility and Mobility Ratio 276. Recovery Efficiency 277. Displacement Sweep Efficiency 279. Volumetric Sweep Efficiency 279. Permeability Variation 284. Estimation of Waterflood Recovery by Material Balance 292. Prediction s 293. Perance uation 293. 1 4 Reservoir Engineering Estimating Waterflood Residual Oil Saturation ................................... 301 Material Balance 301. Well Test Analyses 302. Coring and Core Testing 304. Tracer Tests for Determining Residual Oil 309. Geophysical Well Logging Techniques 312. Summary of s for Estimating Residual Oils 317. Recommended s for Assessing Residual Oil 318. Enhanced Oil Recovery M e t h o d s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319 Definition 319. Chemical Flooding 320. Gas Injection s 323. Thermal Recovery 326. Technical Screening Guides 327. Hydrocarbon Miscible Flooding 329. Nitrogen and Flue G a s Flooding 330. Carbon Dioxide Flooding 331. Surfactant/Polymer Flooding 332. Polymer Flooding 332. Alkaline Flooding 333. In-Situ Combustion 334. Steamflooding 335. Laboratory Design for Enhanced Recovery 342. References ............................................................................................. 344 5 Reservoir Engineering Reservoir engineering covers a broad range of subjects including the occurrence of fluids in a gas or oil-bearing reservoir, movement of those or injected fluids, and uation of the factors governing the recovery of oil or gas. The objectives of a reservoir engineer are to maximize producing rates and to ultimately recover oil and gas from reservoirs in the most economical manner possible. This chapter presents the basic fundamentals useful to practical petroleum engineers. Topics are introduced at a level that can be understood by engineers and geologists who are not expert in this field. Various correlations are provided where useful. Newer techniques for improving recovery are discussed. The advent of programmable calculators and personal computers has dramatically changed the approach of solving problems used by reservoir engineers. Many repetitious and tedious calculations can be pered more consistently and quickly than was possible in the past. The use of charts and graphs is being replaced by mathematical expressions of the data that can be handled with portable calculators or personal computers. Programs relating to many aspects of petroleum engineering are now available. In this chapter, many of the charts and graphs that have been historically used are presented for completeness and for illustrative purposes. In addition, separate sections will be devoted to the use of equations in some of the more common programs suitable for program- mable calculators and personal computers. BASIC PRINCIPLES, DEFINITIONS, AND DATA Reservoir Fluids Oil and Gas Reservoir oil may be saturated with gas, the degree of saturation being a function, among others, of reservoir pressure and temperature. If the reservoir oil has dissolved in it all the gas it is capable of holding under given conditions, it is referred to as saturated oil. The excess gas is then present in the of a free gas cap. If there is less gas present in the reservoir than the amount that may be dissolved in oil under conditions of reservoir pressure and temperature, the oil is then termed undersaturated. The pressure at which the gas begins to come out of solution is called the saturation pressure or the bubble-point pressure. In the case of saturated oil, the saturation pressure equals the reservoir pressure and the gas begins coming out of solution as soon as the reservoir pressure begins to decrease. In the case of undersaturated oil, the gas does not start coming out of solution until the reservoir pressure drops to the level of saturation pressure. Apart from its function as one of the propulsive forces, causing the flow of oil through the reservoir, the dissolved gas has other important effects on recovery of oil. As the gas comes out of solution the viscosity of oil increases and its gravity decreases. This makes more difficult the flow of oil through the reservoir toward the wellbore. Thus the need is quite apparent for production a 4 Reservoir Engineering practices tending to conserve the reservoir pressure and retard the evolution of the dissolved gas. Figure 5-1 shows the effect of the dissolved gas on viscosity and gravity of a typical crude oil. The dissolved gas also has an important effect on the volume of the produced oil. As the gas comes out of solution the oil shrinks so that the liquid oil at surface conditions will occupy less volume than the gas-saturated oil occupied in the reservoir. The number of barrels of reservoir oil at reservoir pressure and temperature which will yield one barrel of stock tank oil at 60F and atmospheric pressure is referred to as the ation volume factor or reservoir volume factor. ation volume factors are described in a subsequent section. The solution gas-oil ratio is the number of standard cubic feet of gas per barrel of stock tank oil. Physical properties of reservoir fluids are determined in the laboratory, either from bottomhole samples or from recombined surface separator samples. Frequently, however, this ination is not available. In such cases, charts such as those developed by M.B. Standing and reproduced as Figures 5-2, 5-3, 54, and 5-5 have been used to determine the data needed [1,2]. The correlations on which the charts are based present bubble-point pressures, ation volume factors of bubble-point liquids, ation volume factors of gas plus liquid phases, and, density of a bubble-point liquid as empirical functions of gas-oil ratio, gas gravity, oil gravity, pressure, and temperature. More recent correlations will be presented subsequently. Until recently, most estimates of PVT properties were obtained by using charts and graphs of empirically derived data. With the development of programmable calculators, graphical data are being replaced by mathematical expressions 57 54 51 48 E 04 45 - 42 3 s I - U 39 E 36 33 Figure 5-1. Change in viscosity and gravity of crude oil due to dissolved gas. Basic Principles, Definitions, and Data 5 Figure 5-2. Properties of natural hydrocarbon mixtures of gas and liquid bubble point pressure [1,2]. Figure 5-3. Properties of natural hydrocarbon mixtures of gas and liquid ation volume of bubble point liquids [1,2]. 6 Reservoir Engineering MMPLE Figure 5-4. Properties of natural hydrocarbon mixtures of gas and liquid ation volume of gas plus liquid phases [1,2]. Figure 5-5. Properties of natural hydrocarbon mixtures of gas and liquid density and specific gravity of mixtures [1,2]. Basic Principles, Definitions, and Data 7 suitable for computer use. In a later section, the use of such programs for estimating PVT properties will be presented. In the initial sections, the presenta- tion of graphical data will be instructive to gaining a better understanding of the effect of certain variables. Water Regardless of whether a reservoir yields pipeline oil, water in the commonly referred to as interstitial or connate is present in the reservoir in pores small enough to hold it by capillary forces. The theory that this water was not displaced by the migration of oil into a water-bearing horizon is generally accepted as explanation of its presence. The amount of the interstitial water is usually inversely proportional to the permeability of the reservoir. The interstitial water content of oil-producing reservoirs often ranges from 10 to 40 of saturation. Consideration of interstitial water content is of particular importance in reservoir studies, in estimates of crude oil reserves and in interpretation of electrical logs. Fluid Viscosities Gas Viscosity. Viscosities of natural gases are affected by pressure, temperature, and composition. The viscosity of a specific natural gas c