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11 APPNDIX K COAL RACTIVITY ANALYSIS

12 Hazen Researh, In 461 Indiana Street Golden, CO 843 Tel: (33) Fax: (33) April 2, 2 FDRAL XPS TRANSMITf AL Mr Paul White Pioneer Coal Ltd 1535 Druond Road Westville, Nova Sotia Canada BOK 2AO Re: Analyses and Reativity of Pioneer Coal Saple Hazen Projet 9653 Dear Mr INTRODUCTION AND SUMMARY Pioneer Cape Ltd (Pioneer) authorized Hazen Researh In to ondut tests on one subitted oal saple to easure its relative reativity as detennined by the oxygen uptake test in air and the selfheating test in oist oxygen Pioneer also asked Hazen to obtain ultiate, proxiate, British theral unit (Btu), and su1fur-for values The oal saple did not evolve gases (ethane or other low-oleular weight hydroarbons) during the oxygen uptake tests, and the saple exhibited slow oxygen absorption The alulated firstorder oxygen adsorption rates were relatively low, between 18 and 2 hour-i after 24 hours A referene saple of reative subbituinous oal obtained fro the Powder River Basin (PRB) in Wyoing had a higher reation rate of 4 hour-i, twie as high as the Pioneer saple The self-heating tests showed that the oal saple had very little tendeny to self-heat at 74 C in the presene of oist oxygen, J, The ultiate, proxiate, and Btu analyses were onsistent with high-volatile A bituinous oals The sulfur ontent of the oal saple was 126% on a dry basis The oal saple did not exhibit signifiant self-heating at its as-reeived oisture ontent of 881 % The oxygen uptake tests indiated a slow rate of oxygen uptake for the oal saple, I An ployee-owned Copany

13 Mr Paul White April 2, 2 Page 2 TST PROCDUR OXYGN UPTAK TSTS Hazen has adapted the sealed flask test proedure developed by the US Bureau of Mines (USBM)\ to provide a relative indiation of low-teperature reativity of raw or upgraded oals In Hazen's proedure, saples are tested without drying, rather than having been dried and rushed prior to testing, as in the USBM proedure Test results are reported in ters of a first-order reation rate onstant The oxygen uptake test provides an indiation of oxidation and/or oxygen adsorption at abient teperature Neither the oxygen uptake nor the self-heating test should be used to diretly predit spontaneous obustion tendenies during storage of large bulk saples Saples for oxygen uptake tests were sealed in one-liter stainless steel bobs ontaining an air abnosphere A ratio of 1 gras of as-reeived saple to one liter of air was hosen on the basis of USBM work and the antiipated reativity of the range of saples tested The pressure in eah bob was adjusted to sea-level pressure (76 illieters (in) of erury absolute) by injeting air fro a large syringe through a septu fitted into the top of the bob This adjustent allowed eah test to be onduted under standard onditions, without variations due to loal atospheri pressure Pressure easureent was ade via a transduer, whih was fitted into the bob lid The transduer easures fro to 776 erury absolute, with an output fro to 1 illivolts (v) After a bob ontaining the desired weight of oal was sealed air was injeted until a pressure transduer reading of about 1 v was obtained Tests were perfored in a water bath aintained at 24 C (75 F) Pressure transduer illivolt readings were onverted to pressure readings expressed in illieters of erury orreted to a onstant teperature of 23 C Prior to starting tests with oal, eah bob lid and all fittings were heked for leaks by puping eah epty bob to about 76 erury absolute pressure to deonstrate no loss of pressure for about 24 hours The oxygen uptake tests on the as-reeived raw oal saples were run in tripliate Routine easureents taken during the tests inluded bath teperature, transduer pressure (illivolt reading), and elapsed tie for eah flask Typially, after the first day of eah test, readings were obtained about one or twie eah day At the end of the test, the gases above the oal saple were analyzed for oxygen, nitrogen, hydrogen, arbon onoxide, arbon dioxide, ethane, ethane, and aetylene 1 Miron, Yael, Sith, A C, and Lz:lra, C P (199), Sealed Flask Test for valuating the Self-heating Tendenies of Coals, US Bureau of Mines, Report of Investigations RI 933

14 Mr Paul White April 2, 2(XX) Page 3 Assuing that all pressure depletion was a result of oxygen uptake by the oal, the total pressure reaining in the flask opletely depleted of oxygen would be about 61 erury absolute This assues no byprodut gas fonnation (CO or CO2, for exaple) Generally, CO2 would be expeted to represent byprodut gas generated or released in greatest aounts at abient teperature Based on USBM data, oals that have been dried evolve uh less CO2 than fresh, raw oal saples In any event, the byprodut gas foration was expeted to be inor relative to oxygen uptake The rate of oxygen uptake is a funtion of the type of reation and the rate of reation A rate onstant is appliable to speifi test onditions (teperature, oal-to-air ratio, partile size, et), as shown below: -dc = kc -a;- where C is the onentration of oxygen, k the rate onstant, t the #e, and n the order of the reation By plaing dtis equationin its logarithi fonn, we obtain: -log (dcldt) = n log C + log k The slope of the plot of dc/dt versus C is the order of the reation, D By rearranging and integrating the original differential equation fro t1 to we obtain the following for a first-order reation (n = 1): In (CICt> = -k (t2 - tt> where: C1 = (76-6OO8)n6 = 295 ai C2 = (P 2-6OO8)n6 Hazen Researh,

15 Mr Paul White April 2, 2 Page 4 and where: CI = Oxygen onentration (or oxygen partial pressure reaining) at tl, at = Oxygen onentration (or oxygen partial pressure reaining) at, at p 2 = Absolute pressure in Hg, at elapsed tie, - lapsed tie, hours k Rate onstant, hour-i First-order reations also follow the general guideline that equal ties are required to redue, by the sae relative aount the value of C starting fro any initial value The rate onstant is used to opare the relative differenes in oxygen uptake fro one saple to another Generally, for siilar types of oal, higher rate onstants indiate greater reativity Rate onstants an vary by as uh as two orders of agnitude, depending on the reativity of the saple, storage onditions (previous exposure to oxygen), partile size, teperature, et SLF-HATING TSTS The self-heating test used at Hazen provides a relative oparison -'bf the self-heating tendenies of oarse oal saples by subjeting the saples to worst-ase onditions in a ontrolled environent By elevating the teperature of the saples to approxiately 74 C and then passing war oist oxygen at approxiately 74 C through the saples, onditions onduive to selfheating are produed The ehanis of self-heating has two steps: I) oisture adsorption on the surfae, whih raises the teperature due to the release of the latent heat of ondensation, and 2) if suffiient oisture ondenses on the surfae, it will raise the teperature of the oal enough to self-heat by adsorption and heial reation of the oxygen with the oal It should be noted that the test is intended only to provide a relative oparison of the saples under siilar onditions, not to predit the behavior of the produts in storage or in transport Beause exposure of saples to air or oxygen prior to testing an signifiantly affet test results by altering the surfae reativity, onsideration should be given to the sapling and storage ethods eployed The self-heating reator onsists of a stainless steel haber with a false botto A fine stainless steel sreen supports a sand bed that evenly disperses the gas entering fro the botto through the oal bed above A theroouple loated in the side of the reator extends into the enter of the oal bed A seond theroouple extends vertially fro the lid of the reator to near the botto of the oal bed Oxygen is passed through a water bubbler loated inside the oven, so that the inlet gas is preheated and saturated with oisture at the reator inlet teperature To run a test, the reator (ontaining a three-kilogra saple) and gas saturator were first purged with nitrogen and preheated overnight to approxiately 165 P (74 C) in a losed oven Oxygen flow was then started at 15 liters per inute Gas exiting the reator passed through a ondenser to reove oisture and then into a gas analysis train, whih analyzed for hydrogen, oxygen, nitrogen, aroon onoxide, arbon dioxide, ethane, ethane, and aetylene The teperature of Hazen Researdt k'i

16 Mr Paul White April 2, 2 Page 5 the oal inside the reator and the oposition of the gas leaving the reator were onitored throughout the test The tests were ontinued for approxiately five hours, or until the teperature of the oal bed exeeded 15 C At the onlusion of the test, the flow of oist oxygen was stopped, and dry nitrogen was introdued while the reator ooled ULTIMAT, PROXIMAT, BTU, AND SULFUR FORMS These standard tests were run aording to ASTM Proedures and D-3172 TST UL TS OXYGN UPTAK TS Figures la through lc (enlosed) show the pressure history of the oxygen uptake tests for the oal saple run in tripliate Figure 2 (enlosed) shows the results fot the reative referene PRB saple Table 1 shows the results of the gas analyses A saple of gas was reoved fro the head spae of eah of the three Pioneer saple flasks and fro one referene PRB oal saple flask using a gas-tight syringe Table 1 Pioneer Coal Ltd Oxygen Uptake Gas Chroatograph Data The oxygen ontents of the were very siilar, at 14% atospheres above the tripliate Pioneer saples after nearly 12 hours The reation rate alulated fro these test data assues that the rate Hazen ReseIW'h

17 Mr Paul White April 2 2 Page 6 of oxygen absorption is a first-orner reation with respet to oxygen onentration The oxygen onentration above the ore reative PRB oal saple was 2%, about I % of the starting value of 295% SLF-IlA TIN G TSTS The self-heating test with the Pioneer oal saple was uneventful, as shown in Figure 3 (enlosed) The teperature of the bed never rose above the :tloc error band of the starting teperature When the flow of oist oxygen was started, the lower-bed teperature was 75 C During the next hour, this teperature briefly rose to 8 C After two hours, this teperature returned to the starting teperature of 75 C No arbon onoxide and only trae aounts of arbon dioxide were deteted, at 4 to 55% ULTIMAT, PROXIMAT, AND BTU ANALYSS Table 2 (enlosed) shows the results of the ultiate, proxiate, and Btu analyses The Pioneer oal an be lassified as high-volatile A bituinous oal, aording to the 1994 Annual Book of ASTM Standards, Volue 5 D 388 This lassifiation is based on a flxed-arbon ontent of less than 69%, volatile ontent of over 31 %, and HHV of over 14,(XX) Btu/lb (all on a dry, ineral-free basis)! If you have any questions onerning this report, please all Mr Rik Kenney or e Sinerely,,1;,,l,;:e:,,<z2 Robert A Reeves, P Projet Manager RAR:wk nlosures x: Rik Kenney,Hazen 2 Perry, R H and Green, D W, loo it, p 27-4 Hazen Reseaa,

18 !?iq OQ) :1: -t N Ḡ) Coo - ': "C W t::> D! u: "C t- o - <- - -Q o:- t! "Q ""ee?:!e QC/)! e t")t")!?ot") ON :1: -t N ii: L; 1!o oec &"'6 '-o '-!! e,>l:o scc 9:o -'- -:i:! oot 'B UZ e e! g> :I:-o [LIJ NNCDO M Q :g l== ;t5-- ee s ejj :: a N > i= ooo (o)nn 8uIUIRW8H zo % Ut- i i - ("i! CJ a: f «) N - Co 'ii -- (/) - I e U a '- a: 8 «) «) C N " - :I: D -g os o{ 9 «) "i U 21 u 8!! e 'B $ z :1: sf: J i N f

19 I I!!OQ OQ ('\I < ('\1('\1() ; j j (/) - - "C - )( W j -Co ::J a a) e u: "C 8 qq ('\I! ll L:"":e: 2-- f!! B>i:O -S;- 2o a:'" "jj oot: :go Oz - a: 2'> :I:-o IIrn NN M, a Ẹ e Q 8 - " os - n: " 8 U) - "Ci U) "iu u a: d I a: : NC :l: '5J I i N! (/) <M := -J -Q I :- (!) f JI! Qee!e QC/) e i t -a;!ll ::;_- e -!! -J-J I 8! 'Ḅ Il: Z 1 il

20 '" Q) n - C -: Q) "C )( w Q ::> C G> ) (I) u: "C a> Q) CJ) L- a> -J I - e "'a e(,) Q> [rnm NN(OQ) to- CO t= "ill ;;:t:_-!! :ee ejj It " Q a 8 - " e, J e '6ṫI a: j z - a: " C/) 1U u : () C) ii: <i I GI a: :I: fj G J i N f

21 - U Q) > "'i (/) -; :u Q) = ; C - "C W Q => u u: "C (/)! I - ĠQ eo:!: Q> IJ]JM NNCOQ r- U) :8 ee "t: == "'iitl ;;s-- e! -o2!ee ejj Ik:ee e e fj)fj)! Q) GI N "i) - U - Q " '-' - C U) = "5 - GI '- OJ : 8 - " g n :I: -g -C - U),g i 1) = 8 " - GI 'B N CJ Q) : GI -C) - u z 1 :! Q Q) u t '1 I j J J

22 a a Q)Q)o 1-1-;,-'- -= B Q)Q) a: a: '- Q) U Q)=ON :2 -JU t t i se ua/\ u! ap!xo!o uoqje % 46!aM ) o o ) N T- 8CO) "CO (J 'Ḡ) G) a: I (I) - "5 (I) It) G)r d 8 N - ::J C Q) i= o W _ (1) G)1t) -- C) :I: :;: CO G) :I: - -a; (/) M e :JC) ii: e 8) Q) (l: Q) N :I: 8 It) - - N 8 < :) 6ep 'ajejoowal N

23 I Table 2 Ultiate, Proxiate, Btu, and Sulfur Fors Analyses I t" I I Hazen Researh,