4P42 Section: 1 .I Reference: 2 Title: Steam: It Generation And Use, 38th Edition, Babcock and Wilcox, New York, B ITUMINOU COAL COMBUSTION AP-42 Section Reference Number 1 149 3 Q Babcockg Wikox D 161 East42ndStreet, NevrY0rk.N Y 10017 I L"" Price $15 .. .,h' j9th edition of "Steam," a book by :k,& Wilcox Company that details Copyright 0 1975 by The Babcock & \Vilcos Company wces in the production of steam Revised thiry-eighth edition iization of fuels. First printing :2nt change in this new edition is ?d coverage of nuclear steam gen- ipment in recognition of the grow- :rice of nuclear fuels as a source 3r the production of steam. [ion also reflects the augmented m quality control, which has ef- mtant improvements in product ing the last twenty years concur- large increases in the capacity of steam generating units. i .issue of "Steam" appeared in long after a New Jersey engineer ohen Wilcox applied his knowledge .culation theory to perfecting a new cept. In 1867, Wilcox formed a 2 with George H. Babcock and the Qcock&Wilcox Company succeeded ttle more than a century since the' I was formed, B,&W has grown from id one product into an organization ian 36,000 men and women em- lacilities throughout the world. Its ring activities range from nuclear o specialty steels and refractories ed machinery. npanY gratefully acknowledges the ooperation and loyalty of its patrons syees. which have made possible ~~,bc~~l:& ~vilcox~orrtporiy. AII rights rcscrccd a Igj5>j960, 1963, lgj2, by UtiOnS in the field of steam genera- ?'hisbook, m,y ,,ads tjLcrcof,moy riot be reproduced ita atry for,jr toilhod SreSSeS the hope that this volume Gritten permission of the publi.sIm t@x tlmulate further advances in Stea rn/its generation and use Babcock&Wilcox 161 East42ndStreet NewY0rk.N.Y. 10017 Copyright 0 1975 by The Bahcock & Wilcax Company Revised thirty-eighth edition Fint printing 0 1955,1960,1963, 19i2, by The Babcock & Wilcox Cnnipuny. All riglita resewed. This book, orony parts thereof, may not Lc reproduced in any form without written permission of the publisher. Librory of Congress Catalog Cord Number: 75-7696 Printed in the United Stores of Americo 22 Sampling of coal 290 21 Although thc coal consumption in a ccntral station may be incasured in thousands of tons per day, the samples 20 nscd for laboratory ;in;ilysis are incnsurcd in grams. It = c is tliercfore important and difficult to obtain representa- 2 280 19 .E c ” tivc sainplcs of coal. IhW playcd a prominent part in P .-- 18 resolvirlg this dilliculty, and thc first ASTM Standard for G !? Sampling Coal. (I1 21) was based 1;rrgely on the work of 270 17 9 3? B&W pcrsonncl. : II ASTM Standard 11492 now in usc was developed, a 16 adoptcd in 1948, and rcapprovcd in 1958. In this stand- 260 15 ard, which is less laborious than thc original, allowances arc made for the probable ash content of the coal, per- 14 mitting the use of smallci gross samplcs for the coals of lower ash content. 250 - 13 19M1 ‘61 ‘62 ‘63 ‘64 ‘65 ‘66 ‘67 ‘68 ‘69 ‘70 Two sampling procediires are recognized in thc pres- Year ent standard. 1. Commercial-Sampling Procedure. Fig. 4 Recoverable reserves and the reseNesproduction ratio of natural gas in the United States. (Source. Bureau of Mines.) 2. Special-Purpose Sampling Procedurc. The “Commercial-Sampling Procedure” applies to the average commercial sampling of coal. This procedure is Table 13 Recoverable natural gas reserves and production designed to measure the average ash content of a large in the ten leading states of the US. number of samples within -t 10% to a 95% probability. (Trillion cu ft) The “Special-Purpose-Sampling Procedure” applies to Reserves Production the sampling of coal when special accuracy is required. Jan. 1, 1970 1969 This rocedure should be used to supply samples for the ~~~ Texas 112.4 4.6 classigcation of coals and the establishment of design or performance parameters. The special-purpose sample Louisiana 85.1~~ ~ 7.28 Oklahoma 17.6 1.68 can be one of two sizes, either 4 times that of the com- New Mexico 14.3 1.09 mercial sample, giving an accuracy of e 5% of the ash Kansas 14.1 0.89 content of the coal samples, or 9 times that of the com- California 8.9 0.84 mercial sample, giving an accuracy of * 3.33% of the ash Alaska 5.2 - content of the coal sampled. Wyoming 3.9 0.32 Standard D 492 also sets procedures for reducing gross Arkansas 2.6 0.17 samples and for obtaining samples for standard and spe- West Virginia 2.4 0.21 Mississippi - 0.17 cial moisture determinations. Two additional pertinent - - publications by the ASTM are: Symposium on Bulk Total 264.5 20.11 Sampling (STP242, 1958) and Symposium on Coal Total in the US. 275.1 20.12 - Samplinz (STP 162, 1955). A new method has also been Source, Ameriqn Gas Association, Inc. adopted-in 1968 covering the mechanical sampling of coal.~..~ .-n22’4. ~~-~ Careful coal sampling is of prime importance since any in circumstances which prevented the free access of air. data resulting from subsequent analyses are only as At intervals, wind and water covered this mass with sedi- representative as the sample provided. ment, sand and dirt to form the overburden now found above coal seams. During millions of years, these layers Coal analysis of vegetation were subjected to moisture, heat and pres- Customary practice in reporting the components of a sure, and portions of the cellulose and other organic ma- mal is to use two different analyses, known as “proxi- terials were converted to carbon and hydrocarbons. In mate” and “ultimate.” The proximate analysis is defined this manner wood and vegetation were changed, perhaps as the determination of moisture, volatile matter, and ash, progressively, to peat, brown coals and lignite, subbitu- and the calculation of fixed carbon by difference. The minous and bituminous coals, and finally to anthracite. ultimate analysis from a dried samplc is defined as the The intrinsic ash of coal was largely in the vegetation determination of carbon, hydrogen, sulfur, nitrogen and from the beginning. The extraneous ash came from mud ash, and the estimation of oxygen by difference. The deposits of shale and pyrites that filled the cracks and scope of each is indicated in the following analyses of a crevices caused by thc movemcnt of the earth‘s crust. West Virginia coal, in which the ultimate analysis has Most of the coal mined in the US. corncs from.scams been converted to the as-received basis. 3 to 6 ft thick, with the average about 5.5 ft. One seam The nnalysis on thc as-received basis includes the total ncar Lakc De Sniet, Johnson County, Wyoming, aver- moisture content of coal received at the plant. Similarly, ages more than 100 feet in thickness and acquircs a maxi- the as-fired basis includcs the total moisture content of mum thickness of 220 ft. The thickcst known scam in the the coal as it enters thc Iioilcr furnace or pulverizers. The world, 425 ft, is in Manchuria. various values from such analyses are needed to imple- Steam / Sources of chemical energy 5-9 Coal analyses ing and h;indling equipment and. in the &sign and On asreceived basis (Pittsburgh Seam Coal. West Virginia) arr;ingcment of hcat trnnsfcr surfaces. Mcthods and principlcs of burning arc closely :issociated with specific Proximate Analysis Ultimate Analysis types of equipment, and rcfcrencc should be madc to Component Weight,% Component Weight,% Chapters 9, 10 and 11. Thc nature and effccls of impuri- ties in coal arc discusscd in Cliaptcr 15. Moisture 2.5 Moisture 2.5 One classification of coal is by rank, ix., according to Volatile matter 37.6 Carhon 75.0 the degree of mct;imorphism, or progrcssivc nltcration, Fixed carbon 52.9 Hydrogen 5.0 in the natural scrics from lignite to anthracitc. Volatile Ash -7.0 Sulfur 2.3 matter, fixed carbon, inhcrcnt or bed moisturc (equi- Total 100.0 Nitrogen 1.5 lil)r:itcd moisturc at 30C and 97% humidity), and oxy- Oxygen 6.7 gcn arc all indicative of rank, but no one item completely Heating value, Ash -7.0 dcfilies it. In thc ASTM classification, thc basic criteria Bhi/lb 13,000 Total 100.0 iirc the fixcd carbon and the calorific values calculated on a mineral-matter-free basis. It is necessary, in establishing the rank of mals, to use ment the formulas in this chapter and in Chapter 6. information showing an appreciable and systcmatic vari- Standard laboratory procedures for making these analy- ation with age. For the older coals, a good criterion is ses appear in ASTM D 271. A list of other testing stand- thc “dry, mincral-matter-free fixed carbon or volatile.” ards is given in Table 14. However, this valuc is not suitable for designating the rank of the younger coals. A dependable means of classi- ASTM classification by rank fying the latter is the “moist, mineral-matter-frcc Btu,” Coals are classified in order to identify end usc and also which varies little for the older coals but appreciably to provide data useful in specifying and selecting burn- and systematically for younger coals. Table 14 ASTM standards for testing coal, specifications and definitions of terms ASTM Standards for Testing Coal ‘D 1756 Carhon Dioxide in Coal OD 2234 Sampling, Mechanical, of Coal ‘D 2361 Chlorine in Coal OD 2013 Samples, Coal, Preparing of Analysis ‘D 291 Cubic Foot Weight of Crushed Bituminous Coal *D 410 Screen, Analysis of Coal ‘D 440 Drop Shatter Test for Coal D 311 Sieve Analysis of Crushed Bituminous Coal OD 547 Dustiness, Index of,of Coal and Coke D 310 Size of Anthracite ‘D 1857 Fusibility of Coal Ash ‘D 431 Size of Coal, Designating from ‘D 1412 Equilihlium