Standard Test Method for
Moisture in the Analysis Sample of Coal and Coke1
This standard is issued under the ﬁxed designation D 3173; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 1.1 This test method covers the determination of moisture in the analysis sample of coal or coke. It is used for calculating other analytical results to a dry basis. When used in conjunction with the air drying loss as determined in accordance with Method D 2013 or Practice D 346, each analyticalresult can be calculated to an as-received basis: 1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. 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. 2. Referenced Documents 2.1 ASTM Standards: D 346 Practice forCollection and Preparation of Coke Samples for Laboratory Analysis D 2013 Practice for Preparing Coal Samples for Analysis D 3180 Practice for Calculating Coal and Coke Analyses from As-Determined to Different Bases D 3302 Test Method for Total Moisture in Coal 3. Summary of Test Method 3.1 Moisture is determined by establishing the loss in weight of the sample when heated under rigidly controlledconditions of temperature, time and atmosphere, sample weight, and equipment speciﬁcations. 4. Signiﬁcance and Use 4.1 Moisture as determined by this test method is used for calculating other analytical results to a moisture free basis using procedures in Practice D 3180. Moisture percent determined by this test method may be used in conjunction with the air-dry moisture loss determined in Method D2013 and Test Method D 3302 to determine total moisture in coal. Total moisture is used for calculating other analytical results to “as received” basis using Practice D 3180. Moisture, ash, volatile
matter, and ﬁxed carbon percents constitute the proximate analysis of coal and coke. 5. Analysis Sample 5.1 The analysis sample is that sample which has been pulverized to pass 250-µm (No. 60) sieveas prepared in accordance with Practice D 346 or Method D 2013. 6. Apparatus 6.1 Drying Oven, for coal samples: 6.1.1 For determining the moisture of coal, the oven shall be so constructed as to have a uniform temperature in all parts, have a minimum of air space, and be capable of temperature regulation between the limits of 104 and 110°C. It may be of the form shown in Fig. 1. Provision shallbe made for renewing the preheated air in the oven at the rate of two to four times a minute, with the air dried as deﬁned in 7.1. 6.1.2 In the oven shown in Fig. 1, the door should contain a hole of approximately 3.2 mm (1⁄8 in.) in diameter near the bottom to permit a free ﬂow of air through the oven space. 6.2 Drying Oven, for coke samples. For determining the moisture of coke, an ordinarydrying oven with openings for natural air circulation and capable of temperature regulation between limits of 104 and 110°C may be used. 6.3 Capsules, with covers. A convenient form, which allows the ash determination to be made on the same sample, is a porcelain capsule, 22 mm (7⁄8 in.) in depth and 44 mm (13⁄4 in. ) in diameter, or a fused silica capsule of similar shape. These capsules shall be usedwith a well-ﬁtting ﬂat aluminum cover, illustrated in Fig. 2. Platinum crucibles or glass capsules with ground-glass caps may also be used. They should be as shallow as possible, consistent with convenient handling. 7. Reagents 7.1 Dry Air—Air used to purge the drying oven should be dried to a moisture content of 1.9 mg/L or less. (Dew point − 10°C or less.) Any desiccant or drying method...