ASTM D 2013 - 1986 Standard Method of Preparing Coal Sample for Analysis

March 24, 2018 | Author: Aditya Supriyadi | Category: Variance, Bias Of An Estimator, Errors And Residuals, Statistical Hypothesis Testing, Standard Deviation


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By Authority OfTHE UNITED STATES OF AMERICA Legally Binding Document By the Authority Vested By Part 5 of the United States Code § 552(a) and Part 1 of the Code of Regulations § 51 the attached document has been duly INCORPORATED BY REFERENCE and shall be considered legally binding upon all citizens and residents of the United States of America. HEED THIS NOTICE: Criminal penalties may apply for noncompliance. e Document Name: ASTM D2013: Standard Method of Preparing Coal Samples for Analysis CFR Section(s): Standards Body: 40 CFR 60, Appendix A-7 American Society for Testing and Materials Official Incorporator: THE EXECUTIVE DIRECTOR OFFICE OF THE FEDERAL REGISTER WASHINGTON, D.C. . 3.2.1 Referee Method--This m. Last previous edition D 2013 -72 (1978)". A good text for this purpose is Grubbs. up to and including the individual portions for laboratory analysis.1ethod to obtain repeatable results.3 Two methods are given for preparing the analysis sample for making the moisture determinations: 1. Referenced Documents 2.2 Reduction and division procedures are prescribed for coals of the following groups: 1.7 laboratory sample-the sample.. 60 (250-llm) sieve and divided to not less than 50 g. 1. an instrument. a measure of the chance error as expressed by the variance. 1986.02. 218-226. Current edition approved Aug. Published October 1986. Details appear in standard texts.) indicates an editorial change since the last revision .10 rifJle-a hand-feed sample divider device that divides the sample into two parts of approximately the same weight. Descriptions of Terms Specific to Tltis Standard 3. Originally published as D 2013 . analysis variance which is n0 more than 20 % of the total allowable variance. 3. 4 Discontinued. or a multiple of the standard error (see Practice E 177). "Determination of Quantities Needed in Coal Sample Preparation and Analysis. pp 133-143. 3. 3. 1.6 gross sample-a sample representing one lot of coal and composed of a number of increments on which neither reduction nor division has been performed. 3. F.3 Group A allows smaller weights of laboratory samples to be retained than Group B. not less than the permissible weight given in Table 1. Unknown coals are to be considered under Group B. see 1988 Annual Book of ASTM Standards.9 representative sample-a sample collected in such a manner that every particle in the lot to be sampled is equally represented in the gross sample.~~l~ Designation: D 2013 . No. the year oflast revision." JTEVA. 3 Annual Book of ASTM Standards. 29.1 This method2 covers the reduction and division of gross or divided samples.2 analysis sample-final subsample prepared from the original gross or divided sample but reduced to 100 % through No. 5 Annual Book of ASTM Standards.5 divided sample-a sample that has been reduced in quantity.2.8 precision-a term used to indicate the capability of a person. 1.4 This standard does not purport to address all of the safety concerns.1 Group A includes coals that have been cleaned in all sizes. These lower weights may be used for particular coals if they have been shown by using the procedure of Annex A1. in the case of revision.05.2 to give a sample preparation and. Scope 1.2 Group B includes all other coals. ASTM Test Methods 5 3.3 bias (systematic error)-an error that is consistently negative or consistently positive. 3. D 2234 Test Methods for Collection of a Gross Sample of CoaP D 3173 Test Method for Moisture in the Analysis Sample of Coal and Coke3 D 3 P 4 Test Method for Ash in the Analysis Sample of Coal and Coke from Coal3 D 3302 Test Method for Total Moisture in Coal3 E 11 Specification for Wire-Cloth Sieves for Testing Purposes5 E 177 Practice for Use of the Terms Precision and Bias in . It is intended to be used for evaluation of nonreferee methods.or reapproval.62 T. associated with its use. Vol 05. 2.2 Nonreferee Method-This method may be used for routine work. Vol 05. E.05. or a IJ. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 3." Transactions.ethod shall be used where the possibility of unaccounted changes in moisture content during the reduction and division of the gross or divided sample mu~t be held to a minimum.3.2. 2 For more detailed explanation of this method see Keller. the standard error. 3. if any. 6 236 .23 on Sampling. Vol 232. delivered to the laboratory for further preparation and analysis.86 (Reapproved 1994) Standard Method of Preparing Coal Samples for Analysis 1 This stlll'ldard is issued under the fixed designation D 2013. E. A superscript epsilon (. 1.1 air drying-a process of partially drying coal to bring moisture near to equilibrium with the atmosphere in the room in which further reduction and division of the sample is to take place. G. the number immediately following the designation indicates the year of original adoption or.4 C test-a standard statistical test for homogeneity of variance 6 • 3. July 1982. This method is under the jurisdiction of ASTM Committee D-5 on Coal and Coke and is the direct responsibility of Subcommittee D05. pp. 1. Vol 14. The mean of' errors resulting from a series of observations which does not tend towards zero. A number in parentheses indicates the year oflast reapproval. and for testing of equipment. 1965. Vol 10.4. specifically. 3. collected in accordance with Methods D 2234.1 ASTM Standards: D 197 Test Method for Sampling and Fineness Test of Pulverized CoaP D 410 Method for Sieve Analysis of Coal4 D 431 Test Method for Designating the Size of Coal from its Sieve Analysis4 . Only under certain conditions will this referee method be directly applicable to routine test programs.• "An Introduction to Some Precision and Accuracy of Measurement Problems. 1. 1. sledge. ever residual or total moisture or both.4 Scale-Gross Sample-A scale of sufficient capacity tion (or standard error).. room temperature with a maximum oven temperature of 3.1 Hammer Mill-Completely enclosed to avoid loss method as follows: of dust or moisture.19 top size-the opening of the smallest screen in the over 10°C (18°F) above room temperature.3). 6. 6.20 unbiased sample (representative sample)-a sample 6. the temperature shall not be 3. to 4/min.23 variance of division. 4. the following 4.~~ D 2013 TABLE 1 Preparation of Laboratory Sample Crush to pass at least 95 % through sieve No.2 Porcelain-lar Ball Mill-This mill shall be approxisample and mechanical crushing equipment for the reducmately 230 mm (9.0 in.36-mm) No. 6. its ability to meet specifications. Air changes shall series upon which is retained less than 5 % of the sample (see be at the rate of 1. that do not appreciably increase the ash content for the division of the sample and mechanical crushing of the sample.3 Combined Procedure A and B-The two procedures Equivalent) and Pestle-Only for reducing the small fraction may be combined atany stage of the preparation procedure.16 standard deviation-the square root of the variance.0 in. crushing. and including division and preliminary crushing of any large lumps in the sample before analysis of the single increments.5 Sample Dividers: 237 . case of easily oxidized coals. the sum of squared deviations (or cient size so that the sample may be spread to a depth of not errors) of individual observations with respect to their more than 25 mm (1.) high. Hard-steel Qr 3. 5.25 total variance.11 sample division-the process whereby a sample is reduced in weight without significant change in particle size. well-rounded.m) sieve after 4. the square of the standard devia6. 1. (104°F) in which case ambient temperature shall be used. g A Group A Group B 2000 500 250 50 4000 1000 500 50 A If a moisture sample is required.15 size consist-the particle size distribution of a coal. Divide to a minimum weight of. 6.2 These procedures include methods to be used whenpulverization.1. Summary of Method equipment may be used: 4. 40°C (104°F) unless ambient temperature is above 40°C 3. of sample. and mixing of a gross sample for the purpose of obtaining an unbiased analysis sample.2 Crushers or Grinders-Jaw. 6. and sensitive to 0.3. 20 (850 Jlm) No. sensitivity of 0.14 significant loss-any loss that introduces a bias in 6. Significance and Use 5.1. So2-the overall variance resulting chilled-iron plate with tamper. feeding into the crusher.1 Air Drying Oven-A device for passing slightly final results that is of appreciable economic importance to heated air over the sample.36-mm) sieve subsample by 500 g.) with sides not more than 38 mm arithmetic mean divided by the number of observations less (1.1 This method is intended to provide an analysis sample of coal from a gross or divided sample that has been collected in accordance with Methods D 2234. maintaining a temperature of 10 to 15°C (18 to 27°F) above 3.4 (4.m) sieve. 3. to pass the sieve designated in Table 1.3 Preparation of gross or divided samples for analyses or tests consists of air drying (where necessary). and dividing the gross or divided sample in stages to a small analysis sample representative of the original gross sample.5 g in 1000 g.0 in. 4. or rotary crusher. 60 (250-J.3 Pulverizer or Mill-For final reduction of laboratory sample to pass the No. 3. cone. 3. as well as for other purposes. or hand bar for from collecting single increments. of dust and excessive air currents. particle size reduction.8 (2. in height with smooth.3. increase the quantity of No.1.5 Balance-Laboratory Sample-A balance of suffierrors (deviations) of analysis.24 variance of division and analysis. Si-the variance due to chance .) in diameter and 250 mm (10.) tion of the sample.1 Procedure A-Rimes are used for division of the 6.1. not passing a No. one (degrees of freedom).1.13 sample reduction-the process whereby a sample is 6.2 Procedure B-Mechanical sample dividers are used equivalent. division.75-mm) No. 3.46 kg (100 lb).5 in.023 kg (0.1. equipment for the reduction of the sample.75-mm) or NO. its environmental impact.12 sample preparation-the process that may include air drying.4 (4.1 Air Drying-The following apparatus maybe used: 3.17 subsample-a sample taken from another sample. 60 (250-J.05 Ib) in 45.3 Drying Pans-Noncorroding metal pans of suffi~ of a set of observations. Apparatus reduced in particle size by crushing or grinding without significant change. The analysis sample can be used to determine the value of the coal represented. 3.1. 1 Three processes of sample division are covered in this 6. The oven shall be capable of concerned parties. 8 (2.4 Bucking Board (Chrome Steel) or Mortar (Agate or 4. In addition. a method to determine the percent air dried moisture loss of the sample is provided. mixing.1. flint pebbles or 4. errors (deviations) of sample division. : 3.22 variance ofanalysis. 3. Sda2-the variance hammer mill or other suitable crusher to reduce the sample due to the combined chance errors of division and analysis. A typical oven is shown in Fig.18 systematic error (see bias. Method D 431). In 3.2 Drying Floor-A smooth dean floor in a room free free of bias.l.l. cient capacity to weigh the sample and container with a 3. 60 (250 Jlm) (100 % through) or whenever other laboratory analyses or tests are to be made. 3.21 variance-the mean square of deviations (or errors) 6. hard. are to be determined. Sa2-the variance due to chance 6. and dividing the sample. In this device. It is preferable that feed chutes and enclosed . the containers and subsample shall be weighed.0 em)--i SIDE NOTE-Dimensions are typical but required.27em) Celotex Insulating Boord Attached . The sample shall be allowed to attain room temperature before weighing and further reduction.2 Number of Tests-Before preparing the gross or divided sample. may be used but care must be taken to avoid breakage in transport. handling. and free from excessive air movements.2 Feed Chute-A feed chute shall be used as shown in Fig. (I.5.rimes be used. such as time required for crushing.5.in Fig. the samples are in closed containers attached to the. Riffle divisi~ns should be at le~st three times the top size of coal being divided.36 mm 850). 7. mixing the sample thoroughly.1 Mechanical-A mechanical sample divider using a reciprocating or rotating cutter. 7.2 RifJles-A mapual sample divider which splits the coal stream into a number of alternate elements. The wheel should be rotated at a speed so that the particles fall gently from top to bottom of the container. 6.5. (1. and type of crushing equipment. properly sealed. Also. 6. (11. 7.ole~ __ CL --. the uncrushed gross or divided sample shall be protected from moisture change due to exposure to rain.1 Feed Scoop-A feed scoop or pan having straight sides and equal to the effective width of the riffle shall be useQ to feed the stand-type riffle. and analysis So2. A separate moisture laboratory sample may be required. 7. ~____-4~. . a reserve sample may be desired in case a check analysis or test is required. 1 ' Air Drying Oven 6. (86. FIG. 3. (61.3 em) _ 1--. 6.1 General-The preparation of the gross or divided sample shall be done by trained and experienced personnel. wind. and the weight loss or gain shall be used in the calculation of moisture content.5 While awaiting preparation. sealed with rubber gaskets.27em) angle of 45° with the horizontal wheel shaft.2e~ FRONT I-- 24in. rimer is shown .2.5-t/8m. 6. Precautions 7 . reofed.6 Mixing Wheel-One type of a mechanical device used for mixing the analysis sample. reducing.lm 250/lm 6. 4 Size 4. of the following sizes. ~ a:: w ro ~ <l I U Air Inlet Holes ~ ~ z W . equilibrated to the new atmosphere by air-drying. or noncorroding cans such as those with an airtight. 6. 2. (20. snow. The wheel provides space for a number of containers depending on its diameter and is turned slowly by a small motor and reduction gear.1 The sample preparation operations should be performed in an enclosed space.6 Whenever subsamples are stored or transported. The slope of feed chutes and rimes must be at least 60°. 7.cool. 7.j1~ ~=b====~ + ~-r<l~ ~----~-rL-----~~ 0 4-1/2in. It is necessary that the variance of sample division and analysis Sda2 be not more than 20 % of the total variance of sampling. Sample preparation should be checked at intervals by the methods described in Annex Al or A2. . since moisture loss depends on several factors other than total moisture content.(91. The container should be about half full and never more than two thirds full in order to obtain good mixing of the sample.5. the air drying procedure should not be prolonged past the time necessary to bring its moisture to equilibrium with the air in the room in which further reduction and division are to be made. Glass containers.. or other acceptable devices for dividing the sample.4 em) No. a rotating slotted cone. and portions may be required for grindability and other tests.3 Since most coals oxidize on exposure to air. friction top or screw top sealed with a rubber gasket and pressure-sensitive tape for use in storage and transport of the laboratory sample.J 7. Typical. -The discharge opening of the feed chute shall be the same width as the riffle opening. all operations shall be done rapidly and in as few operations as possible. and sun. _ 8in.75 mm 8 20 60 2.1. on contact with absorbent materials.2. Air Outlet __ I::!.8 Laboratory Sample Containers~Heavy vapor-impervious bags. a rotating hopper and spout. with cover and receiver: Celotex Insulating Boord 4 -500 Walt Strip Heaters Blower r 34 in.7 Sieves-A set of sieves whose dimensions are in accordance with Specification E 11.+-(~13_. rim: of a wheel at an 238 . division.. 3. Typical mechanical sample dividers are shown in Fig.0_e~. the number and nature of the analysis and tests should be considered.~~ D 2013 1/2in. atmospheric temperature and humidity.4 In collecting.3 em) I ~.~~l ~ 1/2in.(l5. These illustrate four designs but others may be available.----o ~ 0 0 0 0 o 0 0 0 _ _ _ _ _ __ L_ _ _ _ _ _ 0 ~~ L-36in.4eml-----J __ 6i~. Sieve tests (see 6.7) shall be made and reported in accordance with 239 . Sieve Tests 8. One or more cutters may be used.19) and.1 Weights-The minimum allowable weight of the sample at any stage depends on the size consist. (d) Rotating Cone-A sampler developed by the British National Coal Board.36~mm) sieve shall be made in accordance with Test Method D 197. the variability of the constituent sought. 2(c) shows the totaling hopper that receives the crushed sample and discharges it through a' spout over one or more stationary cutters.1 The errors of sample division are sensitive to the top size (see 3. ' (c) Rotating Hopper and Spout-Fig. 8 (2. 2(a) shows a section of a cutter which is moved across a stream of coai. 7.VI 15 TO 50 RPM 2 / S'MPLE (c) Rotating Hopper and Spout (d) Rotating Cane (5) DRIVE / RP" SA .36-mm) sieve: Sieve tests on the portions passing the No. rotating shaft. . D. (b) Rotating Cutter-Fig.it is important to make a periodic sieve test of the product ofthe sample crusher.. 2(b) shows two cutters attached to a hollow. 9. 2 Mechanical Sample Dividers Method D 410..2 Air Drying: 8. therefore.and the degree of precision desired (Table 1). the subsample shpuld be weighed and its moisture equilibrated with the new atmosphere. and the weight loss or gain used in the calculation of moisture content.. Eacn cutter is designed to extract increments from the feed a'ndto discharge these into the hollow shaft. Two slotted cones' are lacked together and rotated an a vertical shaft so that on each revolution the common slot operating intercepts the falling stream of coal and collects an increment. Procedure 9. FIG. At regular intervals the cutter movement is reversed and a sample increment is collected on each trip through the coal stream.~t 02013 (a) Reciprocating MOTOR AND (b) Rotary Cutter Cutter (5) DRIVE REJECT AND FEED MECHANIS . 8 (2. except when more than 50 % passes the No. 9.7 Whenever a distinct change of humidity occurs during the course of preparation of an air-dried subsample. PLE (a) Reciprocating Cutter-Fig. without loss of coal pariicies.2 In the reduction and division of gross or divided samples for which total moisture content is to be determined.3 Divide the crushed sample by using a large rime. 9. or oha drying floor to a depth of not more than t'Y. Pass the coal through the rime from a feed scoop. to speed up air drying.8 (2.3. Spread the sample in the pan to a depth not to exceed 25 mm (1.5. 9.3. If an oven is not available.' Stirring at intervals will lessen air-drying time.3.3. 9. ' 9.1 Reduce the gross or divided sample to a top size of No.1 %jh.~t 02013 FIG.1 %jh.3. 9r a sample too wet t<:>. and hold it with its front edge resthlg on top of the feed chute.3.1 Gross or Divided Samples-Weigh and spread the moistur.3 through l7 fiust be followed. place it in. or rime pan having a' lip ot opening'the full width of the· rime. if an air drying oven is available. in pans.3.the oven along with the container and air dry until the loss in weight is not more than 0. the precautions in 7. 3 and described in 6.0 itt).2.e sample.iQe Jhe top size of 1.he coaL The coal may be stirred. cru~h without significant loss of moisture. Avoid'excessive drying time. the sample may be air-dried in a room free from dust and excessive air currents. A typical enclosed rime is shown in Fig.2 lJaboratory Samples-Weigh the sample. plus container. . plus pan. 9.75-mm) or No.3.3 Reduction and Division:.36-mm) sieve taking precautions as outlined in Section 7.4 (4. Continue air drying until the loss in weight of the total gross or divided sample is not more than 0. Rimes propedy used will reduce sample variability but cannot eliminate it. permissible weight in accordance with T. 9.3 Procedure A-Manual Riffling: 9. raise thecont'ainer. then slowly tilt it so that refer~e 240 . spread the coal evenly in the container.1 Samples may require air drying in order to feed properly through the reduction and dividing equipment. feed bucket. When using any of the above containeFs to feed the rime.2.3.2. if one is used. Avoid excessive drying.2 Determine the number of passes required in the riming operation from the total weight of the gross sample and the minimum.able 1. 3 Sample Divider (Riffle) 9. 9. 8 (2.2. 8 (2. M. continue reduction and division in accordance with 9.3. 9. 9.3.4 (4. and 8. Section 2. M' = moisture (laboratory sample).6 and 9.3.75-mm).75-mm) or No. reduce to No. A = air-dry loss. and 9.4.2.4. 4 (4. Quickly pass the subsample through a No.2.5 After reducing to No.3). 60 (250-l1m) sieve size as described in 9. Under no circumstances shovel the sample into the rime.4. on a bucking board or mortar and pestle to pass the sieve.2. before extracting portions for analysis (see 6.2. 9. The percentage loss is A.3.4 (4. 9. take at least 60 increments.4. divide the subsample by riming to not less than the quantity specified in Table 1 for a No.4.4.3. 10. 9.8 (2.8 (2.4 (4. weighing not less than 50 g. and then reduce to No.3.4.4. 20 (850-l1m) sieve. 5.5. Reduce the particles retained on the screen. This is the analysis sample.3 Air-Dry Laboratory Sample-The percentage airdry loss is A.7.75-mm) or No.36-mm) with suitable crushing equipment and divide to quantity limits in Table 1 plus a minimum of 500 g.3.75-mm) sieve size.3.4 Reduction and Division of Moisture Samples: 9. At each stage of division.36-mm) sieve size. A air-dry loss gross or divided sample.3. and add to what passed through the sieve and. Divide the ground subsample by rifiling.75-mm) sieve size. 9.1.3.36-mm) sieve size after dividing to not less than the quantity specified in Table 1 for a No.4 Ifthe sample 'Nas reduced to No.3. 9.7 Calculate the total moisture. Divide to quantity limits in Table 1 plus 500 g.1 Reduce the gross or divided sample in stages and divide by suitable mechanical sample dividers (see 6.3.4.3.2. 9.8 (2.6. 9.4 If the initial crushing was only to No. M.A)/lOO] 9.1 Two procedures for reduction and division of gross samples for use in moisture determinations are given in 9. thence into the rime pans.3.6 If an analysis sample is required. the analysis sample.4.8 prior to extracting portions for analysis.3.36-mm) and divide to quantity limits in Table 1 plus 500 g.3.1. as follows: M = [R(lOO . Do not allow the coal to build up in or above the rime slots.3. 9. 9.8 (2. reduce to No. 241 .4.2) until a minimum of 50 g is obtained. 9.2.r ~~ 02013 the coal flows in a uniform stream through the hopp~r straight down over the center of the rime into all the slots. divided sample in accordance with 9. one-half of the sample being collected in a pan.3. 9.2 If the sample is dry enough to reduce to No. air-dry. 9.3.2 Mechanical division ·of the sample consists of automatically collecting a large number of increments of the properly reduced sample.8 (2. Referee Method.4.3.3.3.7.4 (4. mix thoroughly.4. air-dry the gross or divided sample in accordance with 9. 60 (250-l1m) sieve.75-mm) air-dry. Complete the preparation and calculations in accordance with 9.4.1 Before any sample reduction operations are performed. or dribble into the rime from a small-mouthed container.1 The precision of sample preparation (and analysis) can be checked by following Annexes A 1 and A2.36-mm) sieve size subsample may be reduced to pass 95 % through a No. 4. Precision and Bias 10.3 Air-dry the laboratory sample in accordance with 9.1 If the sample is too wet to reduce to No.4. Divide this subsample by riming with the small rime to not less than the quantity specified in Table 1.3.6).4.2 through 9.8 coal and determine the residual moisture in accordance with Test Methods D 3302. and R = residual moisture. 9.5 Divide out the moisture subsample and determine residual moisture in accordance with Test Methods D 3302.7 As an alternative to the procedure of 9. reduce the gross or divided sample with suitable crushing equipment and divide to quantity limits in Table 1 plus 500 g.6 If an analysis sample is required.4 (4.5. 9. 9.8 (2.3. Section 2.4 (4.3. determination of bias is not applicable.2.4. 9. 9. air-dry and reduce to No. 8 (2.3.8 Thoroughly mix. 9.4.2.1 and Fig.4. the No. 9.36-mm). in the case of mechanical division where an increment is not thoroughly mixed with other increments prior to division.A)/lOO] + A where: M = total moisture. 100 % through No.4. in accordance with 9.3.2. This is the laboratory sample.3.2. as follows: M' = [R(lOO . 9. 9.6.3.2 Referee Method-See 1. 9.36-mm) sieve size subsample to a No.2. 60 (250-l1m) sieve and weighing not less than 50 g.75-mm) or No.4 Procedure B-Mechanical Division: 9.7. A' = air-dry loss (laboratory sample).2.36-mm).3 Thoroughly mix the analysis sample.A ')/100] + A' M = [M'(lOO .6 With suitable pulverizing equipment (see 6.3. preferably by mechanical means.2. 9.36-mm).5 Divide out the moisture sample from No.3. Nonreferee Method.3. This is the laboratory sample.7 Calculate the total moisture.4.36-mm) sieve size. 60 (250-l1m) sieve size. continue the reduction and division in accordance with 9.3.3.4.3.3.large number of increments equally throughout the entire discharge from the sample crusher because crushers can introduce appreciable segregation.3. reduce the No.3 Nonreferee Method-See 1. shake or vibrate the rime to facilitate even flow.2 Reduce the gross sample to No.3. and R = residual moisture.1) to quantities not less than those shown in Table 1. This is R.4 If the gross or divided sample was reduced originally to No.4. Distribute this .4. and reweigh the entire gross or +A where: M = total moisture. using the small rime (see 6. If it does not flow freely through the slots. This air-dry loss is A '.3.2 and Fig.3. a portion of each increment be collected by the subsequent stage increment collection process. This is R. weigh.6 above.8 (2. Since this method does not produce a numerical result. NOTE-It is recommended that.8. 7 and 9.2. 8 (2.4 (4.3.8) DETERMINE RESIDUAL MOISTURE IN ACCORDANCE WITH METHODS D 33 2 DETERMINE MOISTURE IN ACCORDANCE WITH METHODS 0.3.36-mm) SIEVE (SECTION 9.4. 8 (2.3.4 and 9.4.3.75-mm) SIEVE (SECTION 9.2.:3173 FOR OTHER ANALYSES FIG.2.6.2.2. AIR DRY.~t D 2013 COLLECT GROSS SAMPLE IN ACCORDANCE WITH METHODS D 2234 REDUCE TO NO.2.8 (2. 9.4.5 REDUCE TO NO.2) ~ ~ WEIGH.75-mm) OR NO. 4 Gross Sample Preparation for Moisture Determination (Referee Method) 242 . 'REWEIGH (SECTION 9.4.36-mm) SIEVE SUBSAMPLE (SECTION 9.3) j REDUCE TO NO.3.4.4) DIVIDE INTO AMOUNTS REQUIRED (SECTIONS 9.3.4.4 (4.2. 60 (250-pm) SIEV SUBSAMPLE (SECTIONS 9.2) NO.2) NO.36-mm) SIEVE (SECTION 9.4. 6) DETERMINE MOISTURE IN ACCORDANCE WITH METHODS D 3173 FOR THE OTHER ANALYSES FIG.8 (2.4.4. ACCORDANC!.4.4.2 and 9..um) SIEVE SUBSAMPLE (SECTION 9.36-mm) SIEVE SUBSAMPLE WITHOUT SIGNIFICANT LOSS REDUCE TO NO..75-mm) SIEVE NO.: WITlt ~ETHODS D 3302 REDUCE TO NO. 60 (250-.3.36-mm) SIEVE SUBS AMPLE WITHOUT SI GNIFICANT LOSS OF MOISTURE IF TOO WET TO REDUCE TO NO.4.4 (4.75-mm) OR NO.75-mm) OR NO.8 (2.3.4 (4. 4 (4.36-mm) SIEVE (SECTION 9. DIVIDE INTO AMOUNTS REQUIRED (SECTIONS 9.36-inm) SIEVE REDUCE TO NO. NO.75-mm) OR NO.8 (2.4) ANALYZE SUBSAMPLEQUANTITY LIMITS OF TABLE 1 DETERMINE RESIDUAL MOISTURE IN .1 and 9.3.3.8 (2.3.36-mm) SIEVE SUBSAMPLE (SECTIONS 9.4) .3. 5 Gross Sample Preparation for Moisture Determination (Nonreferee Method) 243 .~I 02013 COLLECT GROSS SAMPLE IN ACCORDANCE WITH METHODS D 2234 IF DRY ENOUGH TO REDUCE TO NO.8 (2.4 (4.4. however.% VP.6.~I 02013 ANNEXES (Mandatory Information) At.2.2.5 Determine ash in accordance with Test Methods D 3174. A 1. Al. Divide each subsample to no less than the minimum weights as outlined in Table 1. Al. into two equal parts.1. as follows: VP = (l/4N) ~[(XI .1 Make calculations on the first set often samples so that the variance for each of the stages may be checked and corrective action. 4 (4.8.2. the duplicate determinations should be made at different times and preferably by different analysts. 8 (2. If. Al. may be taken. the vanance of the difference between the averages of duplicate analyses.3 Calculation A1.6 Treat three sets of ten samples each in the above manner.8.8 (2.2.2.4 (4.X2)2 + (X3 .8. X4. in duplicate on each analysis sample. Sda2 .36-mm) sieve and divide. Al. if needed. it is desired to crush directly to No.3. Calculate the variances of these combinations: VP.2A Reduce each part of the No. .2.2.2. Al.1 Individual weights should not vary more than ±20 % from the weights given in Table 1 and the average of all tests should be within ± 10 % of the weights.2 The variances can be resolved further in terms of variance due to the first stage of sample preparation. instead of ash.75-mm) sieve laboratory sample 95 % through No.2. METHOD OF CHECKING THE PRECISION OF SAMPLE PREPARATION AND ANALYSIS At.5.x4f + (YI + (Y3 . 60 (250-llm)·· sieve and divide to no less than 50 g.1 This method covers procedures for checking precision of sample preparation and analysis at the various stages. Y3. Al.2 Procedure Al.1 This test can be used for sulfur.75-mm) sieve and divide. Xl.2 Coals used in each series of tests should be of similar ash content. X2 _ VR = (lIN)}: [(Xl X3.8 would give a variance no greater.2. the varianc~ of the difference between duplicate analyses. is given by the equation: Sd/ = Va + V2 + VI Al. A 1.2.8 subsampJe to 100 % through No.3A The calculations of the variances of sample preparation are illustrated in Table A 1.1 Many laboratories are crushing directly to No.3 The total variance of sample preparation and analysis.6. Y2 _Y3. using either rimes or mechanical sample dividers.l Scope A 1. and the variance of analysis. AI. V2.3. V2 = Ih VQ . Al.2. Y2)2 VQ = (2~)}: [(1. and probably less.4 and then to No. Al. X4f + (Yl + X2: X3 + X4 _ . Y4 = individual ash determinations. than crushing to No.Y4)2] where: N = number of tests.1. VI = Ih VR . Al.3 Reduce the No.3. Y4fJ Yl + Y2: Y3 + Y4fJ Al. AI. but for purpose of test it is usually best to use both No. X3. but to find out actual variances of preparation and analysis in the normal routine of a 244 laboratory following a prescribed procedure. Al.1 Reduce the gross sample to 95 % through No.1. The data obtained from tests using consistent sample preparation and analysis method are used to estimate the random errors in the various stages of sample division and analysis. The purpose of these tests is not to find out how accurate a laboratory can be. variance due to the second stage of sample preparation.1/4 VQ. using either rimes or mechanical sample dividers. if desired. Y2. Va.5.2. follow the same procedure as if crushed to No. where: Va Ih VP.4 and then to No.2 Divide each subsample by riming or mechanically to no less than weights as outlined in Table 1.2 If possible. or other determinations. Btu. X2. the variance of the difference between the average of each four analyses.1 The analysis of variance is based upon the calculations of mean squared differences with the eight determinations for each sample taken in different combinations.2 Continue this cycle oftests until three successive sets of ten samples are satisfactory. Al.4. VI.36-mm) size instead of to No. Yl.4 and 8 sizes since we can assume that crushing directly to No. into two equal parts without discarding. VQ. VR. 00 -0.03 10.0182 0.10 0.12 -0.2 = Y(1 = 0.93 12.52 12.38 119.02 -0.00 -0.11 -0.0081 0.0182 0.0066 Sd.07 0.54 118.14 12.10 11.0323) = 0.57 11.35 12.84 11.21 12.12.0049 0.94 11.0000 0.0012 0.0289 0.0081 0.0323) .0456 12.09 11.2932 0.12 11.15 118.0009 0.28 12.82 11.80 11.0004 0.03 0.0121 0.09 0.02 -0.05 10. 0.48 118.00 10.11 10.1.38 11.84 12.78 11.61 11. Thus.05 12.02 -0.65 11.0100 0.50 11.03 0.09 -0.20 12.0036 0.0081 0.17 12.15 11.60 11.23 0.13 12.44 11.00 10.05 0.02 12.0144 V.20 0.22 12.0009 0.96 118.79 11.01 0.13 -0.10 0. A 245 .0071) = 0.85 0.01 12.WI (0.WI (0.77 11.45 12.28 12.5491 + 0.37 12.03 -0.04 12.70 11.02 -0.0256 0.03 -0.21 0.11 12.07 -0.58 11.02 0.00 10.0009 0.70 12.77 11.39 -0.96 12.18 0.0009 0.17 -0.0035 + 0.0004 0.1521 0.03 0.19 11.06 0.71 12.57 12.94 11.48 118:78 11.0289 0.0874 12.60 12.57 11.07 -0.17 12.0071) = 0.0049 0.68 11.03 10.0323 VR = 'I'D (0.02 0.0002 0.57 11.74 12.94 12.20 11 :73 12.2162 0.0006 0.58 11.0056 0.72 12.04 10.0064 0.69 11.11 -0.0203 0.93 12.0009 0.85 11.57 118.0691 + 0.03 -0.15 11.85 1 2 3 4 5 6 7 8 9 10 Total Average Test No.63 12.0400 0.18 -0.90 VP = '140 (0.95 11.0456 + 0.0016 0.76 11.59 11.62 11.45 12. X(1 + 2)/2 12.17 -0.07 0.51 12.81 11.0691 Y1 Y2 Difference Difference2 Y3 Y4 Difference Difference2 12.0049 0.1122 0.36 12.0552 0.1 Illustrations of the Calculation of the Variances A of Sample Preparation at the Various Stages and Analysis X1 X2 Difference Difference2 X3 X4 Difference Difference2 12.04 0.0035 V2 = '12 (0.15 11.09 -0. data taken at intermediate steps are not consistent within limits of these rounding errors.57 11.72 12.0324 0. the difference 0.88 11.06 0.73 11.05 10.0156 0.81 12.0036 0.00 10.32 11.76 12.39 11.0081 0.0022 0.60 12.45 118.08 12.0121 0.14 -0.0001 0.84 1~n 11.0000 0.0306 0.73 12.60 12.0169 0.81 12.12 0.46 0.0025 0.99 12.84 11.09.0138 0.72 12.0969 Test No.71 12.07 0.61 11.87 12.17 0.0009 0.2932) = 0.01 -0.0056 0.0036 0.17 12.60 11.0144 + 0.0056 0. 1 2 3 4 5 6 7 8 9 10 Total Average X(3 + 4)/2 12.04 0.0840) = 0.06 -0.09 -0.23 12.12 12.100 0.47 11.03 12.52 12. = '12 (0.0066 = Y(3 + 4)/2 12.01 12.13 0.42 .11 -0.07 2 shows a result of 0.00 10.0004 0.05 -0.21 -0.52 118.16 -0.08 0.0293 Then: Va = '12 (0.8 11.0004 0.02 12.70 11.10 12.86 12.13 10.0056 0.01 .04 0.40 12.04 0.11 .0000 0.59 '11.37 119.53 11.17 -0.07 12.0462 0.0025 0.47 12.46 11.0293) .0036 0.0324 0.16 -0.93 12.03 0.0441 0.04 12.35 12.21 12.87 + 2 + 3 + 4)/4 12.00 -0.13 -0.5491 0.~t 02013 TABLE A1. 1 2 3 4 5 6 7 8 9 10 Total Average Test No.Q7 0.0289 0.12.14 0.0081 0.90 12.0144 0.0272 0.33 0.82 0.0071 VQ = '120 (0.60 11.96 -0.94 X(1 + 2 + 3 + 4)/4 Y(1 12.07 0.0840 Difference Difference2 Difference Difference2 0.0036 0.0056 which is correct when all places are carried in the calculation.42 11.10 12.0245 This table contains data taken from a computer printout with rounding errors that are not involved in the over-all calculation.00 -0.92 118.10.81 Difference Difference2 0. Average Test No.67 10.0004 0.06 -0.0196 0.0000 0.69 11.00 10.06 0.40 119.30 11.36 118.07 + 2)/2 12.10 10.88 -0.05 11.73 11.0874 + 0.88 118.0210 0.0969) = 0.0016 0.01 10.40 12. 1 2 3 4 5 6 7 8 9 10 Total . 99.2 Divide the sample into four equal parts. the highest individual ash sample in the group.3 Make progressive checks a~ t:p.4 Analyze each analysis sample for dry ash content. METHOD FOR DETERMINING THE OvE:R. and (~X)2 = sum of the ash results.~:ALL VARIANCE OF DivIsION AND ANALYSIS4 where: Sda2 = variance of division and analysis.1 Legitimate estimates of the variance of division and analysis. A2. A2:2. follow the procedure described in Method D 2013 for the necessary information to improve techniques of division and analysis. according to the normal routine laboratory procedure.2. 24.2. can only be made using data obtained from tests that were run using consistent division and analysis methods. Investigate values in excess of thi~ ratio before proceeding with the test.1 Crush the gross sample to the same mesh as that normally obtained when preparing the gross sample for processing. the variance of division and analysis may be taken as the over-all average Sda2 of the 30 sets of data.(~xf/4]/3 (5) 246 .1 Scope A2. A2. In any group of five estimates of Sda2 based on four subsamples for each es!i:ti1ate.3 Reduce the four subsamples to laboratory analysis samples. A2.1. Any gross change in the division and analysis methods or in the ash characteristics of the test coal will nullify the test results. in 19 out of 20 cases. The behavior of samples 21 to 30 indicates that trouble can be expected when the ash exceeds 15 % (see Table A2.1.1. If these criteria are met. in 19 cases out of20.2. A2.2 Procedure A2:2.e work is carried out by using the data in groups of five.~t 02013 A2.1). quantity squared.2 Calculate the variance of division and analysis for each gross or divided sample from the "within set sums of squares" for the replicate detenninations as follows: Sd/ = [~X2 . and A2. A2.1' The following four-step method uses the regular gross or divided samples obtained from normal sampling operations: A2. gross sample No.1. In additioni after completing 30 sets.2.1. x2 = s. In this example.4 Example-A complete example illustrating the procedure for determining the variance of division and analysis is given in Table A2. the ratio of the largest group average to the over-all average should not exceed 1. (19.um of the squares of the four ash results.1.88.2.2.28 % ash) has an unusually high variance of division and analysis. Coals used in these variance tests should be of similar ash content. If these criteria are not met. by groups of five. the ratio of the largest estimate to the average of the' llfouP should not exceed 2. Sd}. A2. 3571 55.39 0.0665 0.86 0.15 2.0185 0.0227 0.56 1.02 1.47 4.80 2.38 6.6940 0.0284 0.0931 2.0868 68.52 18.0926 1.0033 .27 4.1281 0. and the risk of infringement of such rights. This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised.1406 18.11 0.7922 0.23 1.59 4.2979 18.18 8.05 17.0005 0.2223 0.3898 42.43 4.61 3.94 4.98 2.90 1.34 14.52 3.2423 0.86 5. A The American Society for Testing and Materials takes no position respecting the validity of any patent rights asserted in connection with any item mentioned In this standard.71 2.4289 0.55 22.3684 128.78 2.65 2.0973 0.10 13.88 in 19 cases out of 2 0 . ' .29 1.1573 0.54 2.87 2.7068 68.0873 0.8031 1. are entirely their own responsibility.0427 0.81 4.9474 311.44 22.88.42 2. 247 .62 11.48 5.58 5.7819 128.1 Determination of Variance of Division and Analysis-Use of Four Analysis Samples for Each Gross Sample NOTE-10 % ash was subtracted from each of the ash results listed to simplify the calculations.36 35.0450 0.0068 0. o Above limit of 1.64 12.1786 0.2603 0.7230 8.46 2.09' 0.74 3.98 8.17 3.2945 0.23 5.0673 0.84 5..25 0.65 5.51 3.80 4.59 5.2556 55.8902 27.17 0.05 0. 0.93 3.24 1.3752 128.13 2.74 0.0599 0.47 2.37 2.6669 0.40 "C" for individuals in subgroup. 1916 Race St.35 4. Philadelphia.64 5.90 4.89 2.0470 0.1995 0.57 1.46 3.4270 66.9792 179.43 3.59 2.66 4.0355 0.03 4.64 2.11 5.1322 50.53 2.80 2.33 14.13 5.56 5.9024 311.33 21.11 11.0999 0.15 3. B "C" for subgroup averages. (1) Gross Sample Number 1 2 3 4 5 Average 6 7 8 9 10 Average 11 12 13 14 15 Average 16 17 18 19 20 Average 21 22 23 24 25 Average 26 27 28 29 30 Average Over-all average Sda2 (2) (3) (4) (5) Analysis Samples 2 3 4 1.15 0.6769 8.73 2.45 8.5770 0.69 5.48 9.21 4.14 0.42 0.1797 0.-- - ---- --- -- ----- ~I 02013 TABLE A2.0023 0.0291 0.1601 0.0162 0.67 0.89 2.52 4.57 3.91 1.0273 0.40 4.6772 49.12 0.25 14.5883 103.99 3.42 2.28 8.09 15.44 16.54 0.2779 0.92 5.17 1.14 0.22 1.37 20.11 (6) (7) (8) (9) (10) (11) (12) Average Sets of 5 Sda2 CIA CIB ~x ~X2 (~x)2/4 (6)-(7) (8)/3 = Sda2 5.15 0.70 3.28 6.0819 0.58 1.0007 0.3962 0.1381 0.88 4.6466 21.53 3.56 0.69 0. Users of this standard are expressly advised that determination of the validity of any such patent rights.07 4.0015 0.7187 111.80 3.3879 10.81 15.85 2.93 0.76 0.40 16.73 6.7386 81.0050 0.0460 0.39 4.25 8.3132 40.3460 103.6981 74.93 .0100 0.17 0.0487 0.93 6.73 2.0595 0.0808 0.0515 0.0172 0. either reapproved or withdrawn.3801 0.6320 58.7589 26.0054 32.1321 0.0465 1.73 3.05 5.21 4. Divide individual Sda2 values (Column 9) by average Sda2 (Column 1 0): Re~ults should be bel~w 2.0163 0.2.84 2. Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM Headquarters.0653 0.59 10.66 2.0150 0.87 1.04 8.6461 179. Your comments will receive careful consideration at a meeting of the responsible technical committee.52 0. Divide average Sda2 (Column 10) by over-all averages Sda2 • Result should be'below 1.48 3.29 20.6051 40.0320 0.65 14.2082 10.46 2.70 1.28 6. which you may attend.0021 0.0149 0.61 2.91 12.09 3.1524 38.4537 102.44 3.68 3.09 1. of 20.6281 21.71 4.7445 49.0333 1.53 2.6238 82.71 1.37 1.23 12.9543 30.26 3.13 3.1471 50.8923 27.2919 0.0036 128.0524 0.93 3.2484 66.13 2.67 14. ' .2276 82.02 1.31 8.86 5.97 2.0157 0.5632 303.32 4.6770 26.87 26.93 2.27 34.63 3.00 0 0.40 4.54 4.0534 30.5849 8.6807 58.1424 38.38 3.02 0.99 in19 cases out.67 12.55 5.5402 32.47 3.0982 0.6916 81.02 13.Q109 0.42 9.08 18.2542 102.61 1.18 9.4506 74.0062 0.71 3.66 5. PA 19103.3025 42.08 0.6913 304.47 10.765~ 0.17 1.6672 111.90 4.62 2.47 8.15 0.0244 0. If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards.
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