API MPMS 11 1-2004 Manual of Petroleum Measurement Standards Chapter 11-Physical Properties Data Section 1-Temperature and Pressure Volume Correction Factors fo.pdf

1、 Manual of Petroleum Measurement Standards Chapter 11Physical Properties Data Section 1Temperature and Pressure Volume Correction Factors for Generalized Crude Oils, Refined Products, and Lubricating Oils Adjunct to: ASTM D 1250-04 and IP 200 MAY 2004 ADDENDUM 1, SEPTEMBER 2007 REAFFIRMED, AUGUST 20

2、12 Manual of Petroleum Measurement Standards Chapter 11Physical Properties Data Section 1Temperature and Pressure Volume Correction Factors for Generalized Crude Oils, Refined Products, and Lubricating Oils Adjunct to: ASTM D 1250-04 and IP 200 Measurement Coordination MAY 2004 ADDENDUM 1, SEPTEMBER

3、 2007 REAFFIRMED, AUGUST 2012 SPECIAL NOTES API publications necessarily address problems of a general nature. With respect to particular circumstances, local, state, and federal laws and regulations should be reviewed. API is not undertaking to meet the duties of employers, manufacturers, or suppli

4、ers to warn and properly train and equip their employees, and others exposed, concerning health and safety risks and precautions, nor undertaking their obligations under local, state, or federal laws. Information concerning safety and health risks and proper precautions with respect to particular ma

5、terials and conditions should be obtained from the employer, the manufacturer or supplier of that material, or the material safety data sheet. Nothing contained in any API publication is to be construed as granting any right, by implication or otherwise, for the manufacture, sale, or use of any meth

6、od, apparatus, or product covered by letters patent. Neither should anything contained in the publication be construed as insuring anyone against liability for infringement of letters patent. Generally, API standards are reviewed and revised, reaffirmed, or withdrawn at least every five years. Somet

7、imes a one-time extension of up to two years will be added to this review cycle. This publication will no longer be in effect five years after its publication date as an operative API standard or, where an extension has been granted, upon republication. Status of the publication can be ascertained f

8、rom the API Standards department telephone (202) 682-8000. A catalog of API publications, programs and services is published annually and updated biannually by API, and available through Global Engineering Documents, 15 Inverness Way East, M/S C303B, Englewood, CO 80112-5776. This document was produ

9、ced under API standardization procedures that ensure appropriate notification and participation in the developmental process and is designated as an API standard. Questions concerning the interpretation of the content of this standard or comments and questions concerning the procedures under which t

10、his standard was developed should be directed in writing to the Director of the Standards department, American Petroleum Institute, 1220 L Street, N.W., Washington, D.C. 20005. Requests for permission to reproduce or translate all or any part of the material published herein should be addressed to t

11、he Director, Business Services. API standards are published to facilitate the broad availability of proven, sound engineering and operating practices. These standards are not intended to obviate the need for applying sound engineering judgment regarding when and where these standards should be utili

12、zed. The formulation and publication of API standards is not intended in any way to inhibit anyone from using any other practices. Any manufacturer marking equipment or materials in conformance with the marking requirements of an API standard is solely responsible for complying with all the applicab

13、le requirements of that standard. API does not represent, warrant, or guarantee that such products do in fact conform to the applicable API standard. All rights reserved. No part of this work may be reproduced, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photoc

14、opying, recording, or otherwise, without prior written permission from the publisher. Contact the Publisher, API Publishing Services, 1220 L Street, N.W., Washington, D.C. 20005. Copyright 2004, 2007 American Petroleum Institute FOREWORD API publications may be used by anyone desiring to do so. Ever

15、y effort has been made by the Institute to assure the accuracy and reliability of the data contained in them; however, the Institute makes no representation, warranty, or guarantee in connection with this publication and hereby expressly disclaims any liability or responsibility for loss or damage r

16、esulting from its use or for the violation of any federal, state, or municipal regulation with which this publication may conflict. Suggested revisions are invited and should be submitted to API, Standards department, 1220 L Street, NW, Washington, DC 20005, standardsapi.org. CONTENTS Section 1 Temp

17、erature and Pressure Volume Correction Factors for Generalized Crude Oils, Refined Products, and Lubricating Oils.1 11.1.0 Implementation Guidelines 1 11.1.1 Introduction IP 200; ANSI/ASTM D 1250), and later in their 20C tables. The implementation procedures are now incorporated in this Standard. Fo

18、r business reasons the Tables have been extended to lower temperatures and higher densities (i.e., lower API gravities). Real-time density measurement using density meters has become more prevalent in the industry for input into VCF calculations. These density measurements are often made at pressure

19、s greater than atmospheric. This pressure effect must be taken into account simultaneously with any temperature effect when determining the density at standard conditions. Hence, pressure and temperature corrections have been combined into one procedure. Rounding and truncation of initial and interm

20、ediate values have been eliminated. Rounding will only be applied to the final VCF values. The previous Standard used a format that resulted in CTL values rounded 4 or 5 decimal digits, depending upon whether the CTL value was greater than or less than one. The final VCF values will now be rounded t

21、o a consistent 5 decimal digits. The Standard also provides a mechanism to provide unrounded factors that, when combined, give the overall rounded CTPL. Implementation procedures needed to be updated to reflect changes in computer technology. The 1980 Tables implementation procedure used integer ari

22、thmetic in order to allow all existing computer equipment to achieve consistent results. With the advent of the IEEE Standards and the predominance of 32 bit and higher level machines, this complexity of the 1980 procedure was no longer needed. This procedure now uses a double-precision floating-poi

23、nt math procedure. Flow computers in the field became common for real-time measurement of petroleum fluids. These require improved convergence methods for the correction of observed density to base density. A more robust convergence scheme now accomplishes this calculation. The range of application

24、for the 1980 Chapter 11.2.1 method has been extended to be consistent with the range used here. This is so that a single pressure correction method could be used. Since the 1980 Chapter 11.2.1M method was not completely consistent with the 11.2.1 method, it has been withdrawn. The implementation pro

25、cedure for the pressure correction is now the standard, not the printed table values. When the number of decimal digits is increased and the floating-point math format used, discrepancies between the previous 60F, 15C and 20C Tables become apparent. Starting from the same input density SECTION 1 VOL

26、UME CORRECTION FACTORS FOR CRUDE OILS, REFINED PRODUCTS, NGLs and LPGs are excluded from consideration in this Standard. The combination of density and volume correction factors for both temperature and pressure is collectively referred to in this Standard as a Correction for Temperature and Pressur

27、e of a Liquid (CTPL) (VCF). The temperature portion of this correction is termed the Correction for the effect of Temperature on Liquid (CTL), also historically known as VCF (Volume Correction Factor). The pressure portion is termed the Correction for the effect of Pressure on Liquid (CPL). As this

28、Standard will be applied to a variety of applications the output parameters specified in this Standard (CTL, Fp, CPL, and CTPL) may be used as specified in other API Manual of Petroleum Measurement Standards (MPMS) Chapters. SECTION 1 VOLUME CORRECTION FACTORS FOR CRUDE OILS, REFINED PRODUCTS, as ro

29、unded values, they may numerically fall just outside of the actual limits established by the defining values. In 1980 the correlation for CTL was chosen so that it would be monotonic with respect to temperature (both the function and its temperature derivative). It also did not have any discontinuit

30、ies over a very wide range of temperatures and densities. This does not say that the correlation is valid outside the data that was used to generate it. Due to needs of industry to accommodate commerce at temperature and density ranges well outside those originally tested, the limits of density and

31、temperature have been extended. This extension is purely mathematical. The algorithms that correctly predict volume correction within the original test limits have simply been applied to regions beyond the original temperature and density limits. The following figures show the range of the original

32、data, the extensions to give the previous standards, and the current extensions for the Generalized Crude Oils, Generalized Refined Products, Generalized Lube Oils, Special Applications, and the compressibility factors. Computed values in any of these extended regions should be used with caution. Cu

33、rrently, there are no data in these regions to establish uncertainty. SECTION 1 VOLUME CORRECTION FACTORS FOR CRUDE OILS, REFINED PRODUCTS, however, thermal expansion factors can be determined and these pure compounds can be treated as a Special Application. It is recognized that there are some pure

34、 components whose densities put them in the range of this Standard and the standard(s) for light hydrocarbons. The two standards give results that are of comparable accuracy but are slightly different. It is up to the contracting parties to decide which is more appropriate to use. SECTION 1 VOLUME C

35、ORRECTION FACTORS FOR CRUDE OILS, REFINED PRODUCTS, this is the full VCF. Mathematically, the procedure starts with the density TeTP (, ) (and corresponding volume VVTPTe (, ) expressed at the base temperature T and base pressure Pe. Corrections are made to obtain the density (, )tP (and correspondi

36、ng volume VtP(, ) at the alternate temperature t and gauge pressure P. The thermal correction to an intermediate density (, )tPeis done first: ()()eeTLPTPtC, (1) and then the pressure correction to (, )tP: ()()ePLPtPtC, . (2) Note that the combined correction is simply the product of the first two c

37、orrection factors since: ()()()()()()PLTLeeeeTPLCCPtPtPTPtPTPtC =,. (3) Volume corrections use the same factors since the volume of a fixed mass is inversely proportional to its density: ()()()()eeeeTLPtVPTVPTPtC,= (4) ()()()()PtVPtVPtPtCeePL,= (5()()()()PtVPTVPTPtCeeTPL,= . (6) The density and volu

38、me at temperature t and pressure P can be calculated from the density and volume at base conditions as: () ( )eTPLPTCPt , = (7) ()()TPLeCPTVPtV, = . (8SECTION 1 VOLUME CORRECTION FACTORS FOR CRUDE OILS, REFINED PRODUCTS, based on density in kg/m3at 60F the A, B, C, and D values) but several sets of

39、coefficients for the 60 thermal expansion coefficient (the K0, K1, and K2values) depending upon the liquids classification and density at 60F. SECTION 1 VOLUME CORRECTION FACTORS FOR CRUDE OILS, REFINED PRODUCTS, this need was made even greater by the inclusion of the pressure correction term in the

40、 procedure. For this reason, a more sophisticated “Newtons Method” is used. Newtons method defines a specific way to calculate a new 60value from the previous value in Step 5 above. The non-linear Equations (16) and (17) are “linearized” about each estimate of the 60value. The equations are lineariz

41、ed by taking the derivative of all of these equations with respect to 60. This linearized equation can then be directly solved for a value of 60that gives the observed density o. The solution of the linearized equation is used as the next iterative steps estimate for 60. Newtons methods have two imp

42、ortant properties: (1) when an estimate is near the actual answer, the method is guaranteed to converge and (2) the convergence of the estimate to the correct answer is very quick. These properties give the power and robustness needed in this Standard. The derivation of the iteration equations is in

43、 Appendix F. The detailed steps to implement the iterative procedure (e.g., how to make the initial estimate, checks to keep values in bounds, convergence tolerances, etc.) are in 11.1.6.2. 11.1.3.6 Calculation of CTL and CPL Factors for Base Temperatures Other Than 60F The goal of this Standard is

44、to provide consistent results when performing corrections using either metric or customary units. That is, when one corrects an observed density to the density at alternate conditions of temperature and pressure, the same result should be obtained irrespective of the base conditions used or the unit

45、s in which they are expressed. For the equations and correlations used in this Standard, the 60F base condition must always be applied in the calculation procedure, even when input and output data are expressed in the metric system of units. It was a desire in this revision to modify the equations i

46、n 11.1.3.3 to enable direct input of densities at each separate base temperature (60F, 15C and 20C). Unfortunately this proved impossible to achieve while keeping all calculations consistent. Because of this, the 60F base condition must be incorporated into all of the CTL and CPL calculations used i

47、n this Standard. See Appendix C for details. SECTION 1 VOLUME CORRECTION FACTORS FOR CRUDE OILS, REFINED PRODUCTS, & LUBE OILS 18 11.1.3.7 Calculation Types Based upon the equations used for this Standard, there are three distinct types of calculations when using the 60F base density. These particul

48、ar classifications are based upon how the calculations are performed each calculation type requires the preceding type(s): Type 1. Starting with the density at the 60F and 0 psig base condition, correct the density (and volume) to an alternate temperature and pressure condition. Type 2. Starting wit

49、h an observed density at its temperature and pressure, correct the density (and volume) back to the 60F and 0 psig base condition. Type 3. Starting with an observed density at its temperature and pressure, correct the density (and volume) to an alternate temperature and pressure condition. A Type 1 calculation is straightforward starting with the density at 60F and 0 psig all parameters can be determined and the calculations can proceed in a “feed-forward” manner