1、Designation: D7825 12D7825 18Standard GuidePractice forGenerating a Process Stream Property Value through theApplication of a Process Stream Analyzer1This standard is issued under the fixed designation D7825; the number immediately following the designation indicates the year oforiginal adoption or,
2、 in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers and provides a workflow overview of the necessary steps relate
3、d to generating a Process Stream PropertyValue obtained from the application of a process stream analyzer.1.2 Generating a Process Stream Property Value from the application of a process stream analyzer requires the use of severalASTM standards. These standards describe procedures to collect a repre
4、sentative sample, establish and validate the relationshipto the primary test method, and calculate a property value with an expected uncertainty. Each standard builds or prepares data, orboth, to be used in another standard. The workflow process culminates to produce a process stream analyzer result
5、 that representsa user defined batch of product. The sequence in which the standards are to be utilized is defined in this guide.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establis
6、h appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D3764 Practice for Validation of the Performance of Process Stream Analyzer SystemsD4177 Practice for Automatic Sampling of Petroleum and Petrole
7、um ProductsD6122 Practice for Validation of the Performance of Multivariate Online, At-Line, and Laboratory Infrared SpectrophotometerBased Analyzer SystemsD6299 Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measure-ment System Performance
8、D6624 Practice for Determining a Flow-ProportionedAverage Property Value (FPAPV) for a Collected Batch of Process StreamMaterial Using Stream Analyzer DataD6708 Practice for Statistical Assessment and Improvement of Expected Agreement Between Two Test Methods that Purportto Measure the Same Property
9、 of a MaterialD7235 Guide for Establishing a Linear Correlation Relationship Between Analyzer and Primary Test Method Results UsingRelevant ASTM Standard PracticesD7278 Guide for Prediction of Analyzer Sample System Lag TimesD7453 Practice for Sampling of Petroleum Products forAnalysis by Process St
10、reamAnalyzers and for Process StreamAnalyzerSystem ValidationD7808 Practice For Determining the Site Precision of a Process Stream Analyzer on Process Stream MaterialE1655 Practices for Infrared Multivariate Quantitative AnalysisE2617 Practice for Validation of Empirically Derived Multivariate Calib
11、rations3. Terminology3.1 DefinitionsPlease refer to the individually cited ASTM standards for definitions.3.2 Acronyms:1 This test method practice is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.2
12、5 on Performance Assessment and Validation of Process Stream Analyzer Systems.Current edition approved Nov. 1, 2012Oct. 1, 2018. Published February 2013October 2018. Originally approved in 2012. Last previous edition approved in 2012 asD7825 12. DOI: 10.1520/D7825-12.10.1520/D7825-18.2 For reference
13、dASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the us
14、er of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard a
15、s published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2.1 FPAPV(s)Flow Proportional Average Property Value(s)3.2.2 MLRMultilinear Regression3.2.3 PCRPrincipal Components Regres
16、sion3.2.4 PLSPartial Least Squares3.2.5 PSPV(s)Process Stream Property Value(s)3.2.6 PTMPrimary Test Method3.2.7 PTMR(s)Primary Test Method Result(s)3.2.8 PPTMR(s)Predicted Primary Test Method Result(s)3.2.9 QCQuality Control3.2.10 UAR(s)Uncorrected Analyzer Result(s)4. Significance and Use4.1 The s
17、tandards employed in the Process Stream Analyzer PSPV Generation Flow Diagram each have a specific deliverablethat when combined into a single system produces a PSPV enabling the representation of product by process stream analyzer.4.2 The description of each standard in the process provides the use
18、r with an overview of the application of the standard in theprocess for developing a PSPV.5. Flow Diagram and Work Process5.1 A flow chart showing the process for generating a PSPV is shown in Fig. 1.5.2 The various standards shown in the flow chart are applied in sequence, building on the results o
19、f the previous standards.The end result is a PSPV which is expected to agree with a PTMR for the same material to within the user-specified requirements.6. Supporting Practices6.1 While practices D6299 and D6708 do not appear directly as part of the Flow Diagram/work process, the methodologiesdescri
20、bed in these two practices are incorporated by reference.6.2 D6299 Practice for Applying Statistical Quality Assurance Techniques to Evaluate Analytical Measurement SystemPerformance:6.2.1 The statistical quality control procedures and tools described in D6299 are an integral part to the validation
21、of analyzersby D3764 or D6122.6.3 D6708 Standard Practice for Statistical Assessment and Improvement of Expected Agreement Between Two Test Methodsthat Purport to Measure the Same Property of a Material:6.3.1 D6708 covers statistical methodology for assessing the expected agreement between two stand
22、ard test methods thatpurport to measure the same property of a material, and for deciding if a simple linear bias correction can further improve theexpected agreement.6.3.2 Practices D3764, D6122 and D7235 which are part of the PSPV generation work process all make use of the statisticalmethodology
23、described in D6708.7. Sampling and Sample Delivery7.1 D7453 Practice for Sampling of Petroleum Products for Analysis by Process Stream Analyzer System Validation:7.1.1 Sampling is the initial process in the generation of a process stream property value, equally important as any other processin the c
24、hain it provides the material that everything will be based on. The sampling standard provides guidance on how to collecta representative sample from the sample stream and deliver it to the desired sample destination (line sample point, on-line analyzer,or composite sampler).7.1.2 This sampling meth
25、od is focused on sample stream delivery without the contamination that can be found in processstreams. The end use of the sample is to determine physical properties of the sample so filtering and coalescing are required toprotect the on-line analytical system. Sampling methods like D4177 are designe
26、d to collect a representative amount of sedimentand water so are not conducive to proper analyzer system operation.7.2 D7278 Standard Guide for Predicting and Measuring Lag Times for On-Line Sampling:7.2.1 The time it takes for a sample to travel from the process stream to the analyzer inlet or line
27、 sample point, including therequired flush volume, is a critical piece of information when establishing the relationship between the on-line analyzer and theprimary test method (D7235) and also the validation of the on-line system (D3764 and D6122).7.2.2 The lag time needs to be taken into account w
28、hen collecting samples and recording analyzer reading to correlate with labsample results and process conditions.D7825 1828. Analyzer System Site Precision8.1 D7808 Standard Guide for Determining the Site Precision of a Process Stream Analyzer on Process Stream Material:8.1.1 To properly apply D7235
29、, and as an extension of D7235 the application of D6708, the user needs to have determined theanalyzer site precision over the expected process stream operating range. The process employed to determine the Site Precisionof a Process Stream Analyzer on Process Stream Material results can be utilized
30、as part of a QC program as described in D6299.8.1.2 D3764 and D6122 require that the user has determined analyzer site precision in order to verify that the process analyzersystem is at steady state during the validation process.8.1.3 To reliably calculate the analyzer site precision, infrastructure
31、 must be in place to repeatedly introduce aliquots of one ormore bulk samples under the same conditions as the sample stream.9. Analyzer Calibration9.1 D7235 Standard Guide for Establishing a Linear Correlation Relationship between Analyzer and Primary Test MethodResults using Relevant ASTM Standard
32、 Practices:FIG. 1 Process Stream Analyzer PSPV Generation Flow DiagramD7825 1839.1.1 Guide D7235 covers a general methodology to develop and access the linear relationship between uncorrected analyzerresults (UARs) produced by a total analyzer system versus results produced by the corresponding prim
33、ary test method (PTMRs)that the analyzer is intended to emulate.9.1.2 Guide D7235 describes how the statistical methodology of Practice D6708 is employed to access the agreement betweenthe PTM and the analyzer results, and if necessary, develop a linear correlation to improve the agreement over the
34、completeoperating range of the analyzer.9.1.3 Guide D7235 applies two either of the following two cases: (1) the process stream analyzer system and the primary testmethod are based on the same measurement principle(s), or, (2) the process stream analyzer system uses a direct andwell-understood measu
35、rement principle that is similar to the measurement principle of the primary test method.9.1.4 If the process stream analyzer system uses a different measurement technology from the PTM, this practice also appliesprovided that the calibration protocol for the direct output of the analyzer does not r
36、equire use of the PTM.9.1.5 Procedures are described to ensure that the sample set used to generate the linear correlation are representative of thematerial type and property range for the intended analyzer service, and to ensure that the set provides adequate variation in propertylevel.9.1.6 Prefer
37、ably, line samples are collected in accordance with Practice D3764 from a sampling point after the sampleconditioning system. Taking into account the analyzer lag time (D7278), corresponding analyzer results are obtained. The linesamples are measured by the PTM. The UARs and PTMRs are accessed using
38、 the statistical methodology of D6708 to determineif there is an adequate linear relationship to allow PSPVs values to be estimated based on UARs.9.1.7 Alternatively, the statistical methodology of D6708 can be used to correlate PTMRs obtained from composite samples toFPAPVs generated from the analy
39、zer results using the methodology of D6624.9.1.8 PPTMRs are generated by applying the linear correlation to the measured analyzer result.9.2 E1655 Standard Practices for Infrared Multivariate Quantitative Analysis:9.2.1 Practice E1655 may be used to develop the calibration if the process stream anal
40、yzer system utilizes an indirect ormathematically modeled measurement principle such as chemometric or multivariate analysis techniques where results from PTMare required for the development of the chemometric or multivariate model.NOTE 1While the practices described within E1655 deal specifically w
41、ith mid- and near-infrared analysis, much of the mathematical and proceduraldetail contained therein is also applicable to other analytical methods. The user of E1655 is cautioned that typical and best practices for multivariatequantitative analysis using data from other multivariate analytical tech
42、niques may differ from that described in E1655 for mid- and near-infraredspectroscopies.9.2.2 E1655 describes procedures for collection and treating data for developing multivariate calibrations. Multivariatemathematics are applied to correlate spectra measured for a set of calibration samples to PT
43、MRs for this same set. The resultantmultivariate calibration model is applied to the analysis of the spectrum of an unknown sample to estimate the PPTMR for thatsample. Application of E1655 is limited to models developed by MLR, PCR or PLS.9.2.3 E1655 describes procedures for validating the calibrat
44、ion model. This validation tests for bias in model predictions, andfor the expected agreement between the PPTMRs and PTMRs. Validation of the model is intended to demonstrate the multivariatemodels capabilities, but it is not intended as a measure of analyzer performance. The performance of multivar
45、iate analyzer systemsmust be validated using procedures described in practice D6122.9.2.4 E1655 describes statistical tests which are employed to detect when samples being analyzed exceed the range for whichthe multivariate model has been validated. The analysis of such “outlier” samples represents
46、an extrapolation of the model, andthere is lower confidence that PPTMRs predicted by extrapolation will agree with PTMRs.9.3 E2617 Standard Practice for Validation of Empirically Derived Multivariate Calibrations:9.3.1 If the multivariate model is developed using techniques other than MLR, PCR or PL
47、S, then the model itself should bevalidated using E2617.As with E1655, the validation of the model is intended to demonstrate the multivariate models capabilities,but it is not intended as a measure of analyzer performance.9.3.2 For calibrations developed using Practice E2617, Practice D6122 is stil
48、l used to validate analyzer performance.10. Validation of Process Analyzer Performance10.1 D3764 Practice for Validation of Process Analyzers:10.1.1 For analyzers where Guide D7235 was used to establish the linear correlation relationship between UARs and PTMRs,Practice D3764 is applied for the vali
49、dation of performance.10.1.2 After the analyzer system has been calibrated per the manufactures requirements, and the correlation between the systemand a PTM has been completed (D7235) and implemented, the analyzer system is ready for validation. Analyzer validation isproving that all the previous steps in the work process have been successfully carried out and that the analyzer system producesPPTMRs that predict the PTM results to within the users expectations and requirements.10.1.3 After an analyzer is installed, or major maintenance is conducted, a probationary
