1、Designation: D7454 08D7454 14Standard Test Method forDetermination of Vibrated Bulk Density of CalcinedPetroleum Coke using a Semi-Automated Apparatus1This standard is issued under the fixed designation D7454; 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. Scope Scope*1.1 This test method covers the determination of bulk density of a represent
3、ative 2-kg sample of calcined petroleum coke, aftervibration to increase compaction, using a semi-automatic apparatus.1.2 The procedure is applied, but not limited, to particles passing through a 4.75-mm opening sieve and retained on a 1.18-mmopening sieve. Further, the procedure is applied, but not
4、 limited, to a specific test sample having particles passing through a0.85-mm opening sieve and retained on a 0.425-mm opening sieve. This procedure could also be applied to other sieve fractionsbeing agreed on in the aluminum industry as specified in Annex A1.1.3 The values stated in SI units are t
5、o be regarded as standard. No other units of measurement are included in this standard.1.4 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 establish appropriate safety and health practices
6、and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E11 Specification for Woven Wire Test Sieve Cloth and Test SievesE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method3. Terminology3.1 Definit
7、ions:3.1.1 as-calcined particles, nof coke, those particles that have not been subject to laboratory crushing.3.1.2 bulk density, nof coke, the ratio of the mass of a collection of particles of a specified particle size range to the volumeoccupied.3.1.3 laboratory crushed particles, n of coke, those
8、 particles of petroleum coke that have been crushed in the laboratory.4. Summary of Test Method4.1 The natural 4.75 by 1.18-mm fraction of the original coke is separated from the sample by manual screening, ground to 0.85by 0.425 mm, and fed at a controlled rate into a graduated cylinder on a vibrat
9、ing table until the coke reaches the 50-mL mark.The collected coke is weighed and the bulk density is calculated and reported in g/mL.4.2 The procedure is empirical; close adherence to the technique and apparatus is necessary to ensure reproducible results. Toprovide comparable results in different
10、locations, exact adjustments of operating parameters are required using reference samples.5. Significance and Use5.1 Vibrated bulk density (VBD) is an indicator of calcined petroleum coke porosity, which affects its suitability for use inpitch-bonded carbon applications. (WarningVibrated bulk densit
11、y for a sample of calcined petroleum coke is strongly dependent1 This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.05 on Properties of Fuels, Petroleum Coke and Carbon Mate
12、rial.Current edition approved Oct. 15, 2008May 1, 2014. Published October 2008 May 2014. Originally approved in 2008. Last previous edition approved in 2008 asD7454 08. DOI: 10.1520/D7454-08.10.1520/D7454-14.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer
13、 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 user of an ASTM standard an indication of what changes have been made to the pr
14、evious 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 as published by ASTM is to be considered the official document.*A Summary of C
15、hanges section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1upon average particle size and particle size range. Bulk density tends to increase with decreasing coke size. A narrow particle sizerang
16、e for this test minimizes the possibility for variation due to skewing of the test sample toward either screen defining thesample.)6. Apparatus6.1 Pan BalanceAccurate to 0.1 g, with a capacity of 2.0 kg.6.2 Riffle SamplerEnclosed drawer, approximately 380 by 290 by 360 mm, 24-slot.6.3 SievesMeeting
17、Specification E11.6.4 Sieve ShakerElectrical drive with an automatic timer; should have a rotating and tapping action.6.5 Roller CrusherLaboratory type; glass hardened rolls; roll diameter of approximately 150 mm; roll width of approximately150 mm; gap range from 0 to 12.7 mm.6.6 Thickness Gauges (l
18、eaf-type)0.4, 1.0, 1.5, and 4.0 mm.4.0 mm.6.7 Semi-Automated VBD Apparatus, As shown in Fig. 1. See also comments about installation in Annex A1.6.7.1 Borosilicate Glass Powder Funnels8-cm diameter funnels with 1-cm internal diameter and stems about 3.5 cm long.Tips of funnels should be cut at a rig
19、ht (not oblique) angles (see Fig. 1). The distance between the tip of the upper funnel and thebottom of the vibrating bowl should be around 6 mm.6.7.2 Electromagnetic JoggerWith approximately 175- by 250-mm deck, and shall be capable of vibrating at a frequency of60 Hz.6.7.3 Acrylic ClampTo hold cyl
20、inder.6.7.4 Vibrating BowlHaving a diameter of approximately 7.5 cm and a height of 4.0 mm, such as that being used with rotarymicro riffler.6.7.5 Displacement Probe and Reading DevicePermitting continuous monitoring of amplitude vibration.6.7.6 Graduated Cylinder50 mL, with inside diameter approxim
21、ately 23 mm and height approximately 19 cm.6.7.7 Photoelectric Sensor Switch.6.7.8 Control DevicePermitting real-time adjustment of the vibration amplitude and automatic stopping of the feeding devicewhen the coke level reaches the 50-mL mark.6.7.9 Automatic Timer, Clock, or WatchWith a second indic
22、ator.6.7.10 Line Stabilizer (Optional)Use if the noise on the power line is significant and affects the apparatus performance.6.7.11 Round Level.6.7.12 Balance0 to 300 g and sensitive to 0.01 g.FIG. 1 Example of Semi-Automated Apparatus Set-UpD7454 1427. Hazards7.1 Exercise care in the operation of
23、the roll crusher.7.1.1 Wear safety glasses and keep hands clear when feeding material.7.1.2 Turn power off at the source when equipment is opened for cleaning after the grinding operation.8. Sample Preparation8.1 Reduce the original sample volume to about 1 kg.8.2 Manually screen out the natural to
24、4.75 by 1.18 mm and 0.85-mm fraction.8.8 Adjust the roller spacing to 0.5 mm and grind the 0.85-mm fraction. Manually screen out the 0.85 by 0.425-mm fractionand add this fraction into the same plastic bag referred to in 8.7. Discard the 0.85-mmfraction, if present.8.9 Repeat, if necessary, the grin
25、ding procedure in 8.8 of the 0.85-mm fraction, until all particles pass through the 0.85-mmsieve. It is possible that at this step, about 1 to 3 g of particles larger than 0.85 mm cannot be ground to finer particles. Do notattempt to grind them using roller spacing smaller than 0.5 mm. Simply discar
26、d them (these particles are in general, plate-like shapeparticles and should not be used for bulk density measurement).8.10 Manually mix the contents of the plastic bag.8.11 Divide the 0.85 by 0.425-mm material between two sets of sieves with openings of 0.85 mm and 0.425 mm and their pan.Using a si
27、eving shaker screen out the 0.85 by 0.425-mm fraction for 7 min. Discard the 0.425 mm material.8.12 Transfer the 0.85 by 0.425-mm material into an appropriate plastic container and manually mix the contents (about 100mL of material is needed for analysis).9. Preparation of Apparatus9.1 Install the a
28、pparatus as shown Fig. 1.10. Calibration and Standardization10.1 Calibration of Graduated CylinderAdjust the height of the photodetector, and determine the true volume at the 50-mLmark of the graduated cylinder, following the detailed procedure given in Annex A2. Calibration shall be made each time
29、a newcylinder is used or when the apparatus is moved.10.2 Determination of the Displacement Speed Target of the JoggerDetermine the displacement target, in accordance withAnnexA3, using standard reference materials. Once established, this target shall be kept indefinitely unless the probe, the contr
30、olleror the jogger have to be changed.10.3 Feeding RateCheck/adjust the feeding rate for each sample.11. Procedure11.1 Make sure that the vibrating table is levelled.11.2 Turn on the apparatus at least 10 min before initiating measurements.The power should not be turned off between readings.11.3 Wei
31、gh the graduated cylinder to the nearest 0.01 g, insert it into the clamping device on the vibrating table while ensuringit does not touch the photoelectric sensor, and let the table vibration stabilize to the set points (it takes a few seconds).11.4 Fill the upper funnel with the coke sample.11.5 F
32、ill the cylinder to about half, using maximum feeding rate, to make a constant bed in the vibrator bowl. Stop the feeding,empty the cylinder in the upper funnel, and reinsert it in the clamping device.D7454 14311.6 Using the automatic mode, reset the chronometer, initiate the feeding and adjust if n
33、ecessary, the bowl vibration intensityto obtain the feeding time of 30 6 3 s/10 mL. The feeding will automatically stop when the 50-mL mark is reached. If no feedingtime adjustment was necessary and if the discharge time falls within 135 and 165 s, proceed to 11.7. Otherwise, repeat 11.6 untilthe ti
34、me target is met.11.7 Empty the cylinder in the upper funnel, reinsert it into the clamping device, and let the table vibration stabilize to the setpoints (it takes few seconds). Then, using the automatic mode, reset the chronometer and initiate feeding. The feeding will stopautomatically.11.8 Check
35、 that the discharge time falls within 135 and 165 s (150 6 15 s). If not, return the coke to the upper funnel and repeatfrom 11.6 to readjust the feeding time.11.9 Remove the cylinder containing the coke and weigh to the nearest 0.01 g. Take two additional readings according to 11.7,readjusting, if
36、necessary, the feeding time to meet the target (between 135 and 165 s).11.10 If the difference between the lowest and highest weight readings exceeds 0.40 g, check if the apparatus is properlyfunctioning, and repeat the test until two consecutive runs agree within the specified 0.40 g. Discard readi
37、ngs only if a malfunctionwas identified (for example, the apparatus was not on speed displacement target, or the time target was not met).12. Calculation or Interpretation of Results12.1 Calculate the average of all acceptable weight readings (at least three).12.2 Calculate VBD using the following e
38、quation:Vibrated Bulk Density g/mL!5 Average weight of coke g!Calibrated volume of cylinder mL! (1)13. Report13.1 Report the average of the readings to the nearest 0.001 g/mL.14. Precision and Bias14.1 PrecisionThe repeatability standard deviation has been determined to be 0.0036 g/mL by making eigh
39、t independentdeterminations (0.864, 0.860, 0.854, 0.859, 0.864, 0.859, 0.864, 0.863 g/mL) for a same sample within a very short period of time.The reproducibility of this test methodPrecicion was determined by interlaboratory testing of calcined petroleum coke samples.Samples covers the density rang
40、e included between 0.78 and 0.94 g/mL. Each sample were prepared by participants and statisticaltreatment of data was performed in accordance with Practice E691will be made available on or before December 200914.2 RepeatabilityWith a confidence limit of 95 %, the difference between consecutive resul
41、ts obtained with the sameoperator, the same machine within the same day under constant conditions do not exceed the following value.Repeatability r! = 0.02 g/mL14.3 ReproducibilityWith a confidence limit of 95 %, the difference between two single and independent analysis, performedby different opera
42、tors, with different machines, in different laboratories on identical test material would not exceed the followingvalue:Reproducibility R! = 0.02 g/mL14.4 BiasThis test method is empirical; no statement as to bias is made.15. Keywords15.1 calcined petroleum coke; porosity; vibrated bulk densityD7454
43、 144ANNEXES(Mandatory Information)A1. OTHER SIEVE FRACTIONS USED IN THE ALUMINUM INDUSTRY TO DETERMINED VIBRATED BULK DENSITYA1.1 From a 2 kg as-received sample, split the test sample with a riffle sampler to a subsample of 350 6 50 g.A1.2 Sieve the subsample to collect the as-received particle frac
44、tion to be measured in accordance with Table A1.1. Discard theundersized particle fraction.A1.3 Taking care to avoid overcrushing, crush the oversized fraction of the subsample in a jaw crusher (of the laboratory type,having manganese steel jaws capable of being set to gaps of approximately 3 to 15
45、mm) or roll crusher, and place the materialbetween the appropriate two sieves with a pan on the bottom and a lid on the top. Gently agitate the sieves by hand but vigorouslyenough to collect the crushed particle fraction to be measured and discard the undersized material. Repeat until at least 90 %
46、(andpreferably more) of the subsample passes through the upper size sieve for the particle fraction to be measured.A1.4 Mix the as-received and crushed particle fractions. A minimum of 110 g of sieved, crushed and mixed particles are requiredfor the VBD test. The mixed sample is sieved for 10 min 10
47、 min in a sieve shaker. Discard undersized material.A2. ADJUSTMENT OF THE PHOTOELECTRIC SENSOR HEIGHT AND GRADUATED CYLINDER CALIBRATIONA2.1 Ensure that the table is level, and turn the apparatus on.A2.2 Insert the cylinder into the clamping device of the VBD apparatus while ensuring it does not tou
48、ch the photoelectric sensor.A2.3 Fill the upper funnel with a typical coke sample.A2.4 Make sure the electromagnetic jogger is turned on, fill the cylinder approximately up to the 45-mL line using maximumfeeding rate, and stop the feeding.A2.5 Using the automatic mode, alternately start and stop the
49、 feeding whenever necessary to bring the coke level to the desiredposition (should be the 50-mL line of the cylinder).A2.6 Bring the photoelectric sensor very slightly above the desired position by sliding the bracket (the knob should be unscrewed)while holding the sensor (do not forget to screw the knob afterward).A2.7 Set the vibrating bowl control to OFF to avoid feeding. Reset the chronometer, press START to get the chronometer running,and adjust the photoelectric sensor height very slowly until it stops the chronometer.TABLE A1.1 Sieve Fra
