the coking properties of coal at elevated pressures. - Argonne ...

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to condense excess steam, the pressure of the cooled gases was reduced to atmospheric, and they were then analyzed. A quadrapole mass spectrometer was used to determine the product gas compositions. The flowrate of product gas was determined An experimental run was carried out in the following manner. Appropriate conditions of reaction temperature and reactant gas partial pressure were selected. The flowrates of nitrogen and carbon dioxide or hydrogen were adjusted to meet these specifications as measured by timed readings of the wet test meter. Steam flow was commenced by adjusting the water metering pump. and the coal entered the reaction zone. Finally the ball valve was opened During the first five minutes of the run, the flow of products was rapid due Table 1. Analyses of Illinois No. 6 coal. Proximate analysis (wt. %) Volatile matter Fixed carbon Ash Ultimate analysis (wt.%) Hydrogen Carbon Nitrogen Sulf ur Oxygen Ash Heating Value Moisture free Moisture an(l coal ash free coal 40.5 46.5 13.0 4.7 67.7 1.1 3.8 9.8 13.0 12307 Btu/lb (28619 kJ/kg) 46.5 53.5 -- 5.4 77.8 1.3 4.3 11.2 -- 14148 Btu/lll (32900 kJ/l..P) Free swelling index 3.5 3.5 . . ---- 68
I I to the devolatilization of the coal and the time at every one-quarter revolution of the wet test meter (0.0125 cu ft, 354 cm3) was recorded. After five minutes, the volume reading of the wet test meter was recorded at 3-minute intervals. Discrete values of the concentration of each gas were also read from a digital display and recorded by the operator at intervals of 2.5 minutes, beginning at 5 minutes. The length of time of each experiment varied. In the experiments conducted at 800°C and 900°C, the 10 g coal sample was usually allowed to react until 80- 90% conversion of carbon had been achieved. At 7OO0C, the experiments were terminated after approximately two hours. At the end of the experiment, flow of water to the steam vaporizer and flow of gases were terminated. All heaters were shut down, and the reactor furnace was opened. When the apparatus was cool, the reactor was depressurized and opened. The char and ash were withdrawn and weighed. All condensate was drained from the trap and the volume of water recorded. mediately. The tar filter was removed and weighed im- Results In this study, the influence of the following parameters on the steam gasification rate of Illinois No. 6 coal was investigated: the presence of K2CO3 as a catalyst; the partial pressures of steam, CO and H2; and reaction temperature. 2 The total pressure of the system was held at a constant value of 2.17 MPa (21.4 atm) throughout the study. The total flowrate of gases into the reaction zone was also kept fixed in each experiment at some value between 980 and 1020 sccm. Variation of the reactant gas composition was accomplished by increasing the mass flowrate of steam, C02 or H2 and simultaneously decreasing the mass flowrate of the inert carrier gas, nitrogen. Nitrogen was both a diluent and a carrier gas for product removal. Runs were made at 700, 800 and 9OO0C with the pretreated coal and coal imp--*mated with 10 wt.% K2CO3. The effect of C02 concentration on the gasification rate of K2C03-impregnated coal was studied at a constant steam partial pressure in a series of 6 runs. An additional 6 runs were made with a mixture of steam, N2, and H2 of constant composition to evaluate the magnitude of hydrogen inhibition of the steam gasification rates. Runs were made at each of the three temperatures, 700, 800 and 9OO0C, with both the pretreated coal and coal impregnated with 10 wt.% K2CO3. Using the data of each experiment, a number of calculations were performed. The gasification rate and carbon conversion were calculated from a balance of carbon-containing reaction products. The extent of reaction of the steam was determined from a balance of hydrogen-containing or oxygen-containing products. Reactant and product gas partial pressures were computed at the reactor inlet and outlet. From these partial pressures, the apparent equilibrium constants of the water-gas shift, carbon-steam, and carbon-HZ reactions were calculated. Finnllv. product gas sums and overall material balances were determined for each experiment. Gasification rate The carbon gasification rate was generally high initially, decreased rapidly and then slowly decreased throughout the remainder of the run. Fig. 2 shows typical results obtained at 70OoC with a catalyzed coal sample. The initial peal: in the curve seemed to be caused by devolatilization of the coal, which was €01.- lowed by gasification of the base carbon in the sample. TO obtain a quantitative measure of the reaction rate, the shrinking, unreacted- core model for the case of complete gasification of a spherical, solid particle under conditions of chemical reaction rate control was used to describe the carbon 69
Page 1 and 2:
I / The Coking Properties of Coal a
Page 3 and 4:
Procedure : Hand picked lunips of c
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Apparatus: The equipment for this t
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the total pressure on the swelling
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A comparison of the results obtaine
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was used, however, general trends a
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1 D 13 3 G
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Table 8 L_ Effect os FaeO Compo.lrl
Page 18 and 19: i-l SPARE SAblPLE Plortlc 209 Figur
Page 20 and 21: - z c 100,000 50,000 10,000 0 n 5,0
Page 22 and 23: Flnure 9 SWELLltlG PROPERTIES OF PI
Page 24 and 25: Fi ure 13 EFFECT OF TOTAL PRESSQRE,
Page 26 and 27: TABLE 1. OPERATING CONDITIONS Opera
Page 28 and 29: 1. . 2. 3. 4. 5. 6. 7. 8. 9. REFERE
Page 30 and 31: Figure 4. SCANNING ELECTRON MICROGR
Page 32 and 33: Turkgodan et al. (18) studied the p
Page 34 and 35: Materidl balance on packed bed Boun
Page 36 and 37: These phenomena iiiay be described
Page 38 and 39: Walker, P. L., Rusinko, F., and Aus
Page 40 and 41: -""I- *I,".. I Dlrf".,on Co.1flcl.n
Page 42 and 43: After a variable residence time, th
Page 44 and 45: Changes in Char Chemistry The infra
Page 46 and 47: 20. 21. 22. 23. 24. 25. 26. 27. 28.
Page 48 and 49: 0s-a 00-a OS'S 00-E os-2 00-2 02.1
Page 50 and 51: COAL PYROLYSIS AT HIGH TEMPERATURES
Page 52 and 53: actions, decreasing the secondary c
Page 54 and 55: 01 40 60 TI MEISeC) 80 100 120 140
Page 56 and 57: Reaction Temperature OC In-situ Ini
Page 58 and 59: and the gas velocity is often repre
Page 60 and 61: The mathematical model developed he
Page 62 and 63: si sio Fraction of solid species i
Page 64 and 65: Table 2. Differential Equations Mod
Page 66 and 67: 1 60 I I RUN KE-5 50 T.1121K(1557'F
Page 70 and 71: conversion-time data.* The integrat
Page 72 and 73: catalyzed and uncatalyzed runs were
Page 74 and 75: CATALYTIC EFFECTS OF ALKALI METAL S
Page 76 and 77: %me thermogravimetric measurements
Page 78 and 79: than in steam. Figure 9 shows data
Page 80 and 81: C - C02 REACTION C - H20 REACTION L
Page 82 and 83: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
Page 84 and 85: n 'm L u. t m - L 84
Page 87 and 88: i 5360-096bw \ KINETICS OF POTASSIU
Page 89 and 90: t 5360-096pj There is an interactio
Page 91 and 92: 1 I > \ i I 5360-096bw bed data. Be
Page 93 and 94: I 1. I 5360-096bw ranging from atmo
Page 95 and 96: uY.ku ICHlMAlIC OF MINI-FLUID BE0 R
Page 97 and 98: 800-12-1133 -9 FIGURE IO CALCULATED
Page 99 and 100: Mexico coal. Table 1 shows an analy
Page 101 and 102: ', Complete results from all runs c
Page 103 and 104: I the methanol down to atmospheric
Page 105 and 106: TABLE 3 -----______________________
Page 107 and 108: \ "I N z 107 c. . 0 0
Page 109 and 110: I. INTRODUCTION DIRECT METHANATION
Page 111 and 112: The catalyst development program fo
Page 113 and 114: Preparing process flow diagrams and
Page 115 and 116: \ \ i 1. 2,000 4,000 6,000 8,000 10
Page 117 and 118: (JMS-OlBM-2). The mass spectra were
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I I Fairbridge, R.W. (ed.) 1972, En
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v- W V z d 3 z m 4 ? P m W c3 W m N
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e. \ I , W 2 m 4 t- CI 99-79 noooo
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L Table I: Compositions of High Tem
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\ " \ I For all three coals, the pr
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4 , 1024 1024 3a 3b J Mineral Parti
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The Determination of Mineral Distri
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pyrite crystals in framboids locate
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FIG. 1. TEM MICROGRAPH OF A HIGH VO
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\ \ FIG. 5. SEM MICROGRAPH SHOWING
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\ , species. In fact, combustion ex
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1, It is possible to make a reasona
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\ i SURFACE AND BULK ENRICHMENT OF
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I Coal Ash Sintering Model and the
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5 carried out such sintering measur
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I this ash and other bituminous coa
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forming propensity. However, none o
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t I 153
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CENTRAL ELECTRICIN RESEARCH LABORAT
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157 18 I I a I
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temperature, sulfur species concent
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The facility is fired with coal usi
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Tests have been carried out to dete
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under which conditions sulfur speci
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I TITANIUM L Corn AS A TRACER FOR D
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E 6 i i h \ 1 1 \ on the XRF is cau
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\ ? CONCLUSIONS Titanium can accura
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NY) m * oa
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GFETC constructed a 0.2 square mete
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\: Stage 3. Sulfated ash-cemented a
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I FIG. 1. Initial ash coating on qu
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FIG 9. Limestone bed material alter
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(4) Since the operating temperature
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I I maximum particle diameter leavi
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! suspension chambers and cyclone f
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Pilot Plant of a Coal Fired Fluidiz
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After the fiscal year 1982, the fol
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MBC CBC Fig. 1 Boiler Structure 193
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\ i Table 2. Coal Properties Planne
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-2- more than 3 years, since 1977.
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, I B. 2 which temporarily raised t
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-6- abrasion rate at the bottom of
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\if F3.3 - Particulate Circulation
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\' I/O. analog 1/13. industrial I/O
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ACQUISITION DATA UNIT < I L- J (T)
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SAMPLING SYSTEM FOR FLUIDIZED BED A
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GAS SAMPLING WITH ORIGINAL PROBE-FI
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Remove the quartz tube (gas sample
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' ' The modifications have been com
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n n D 217
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With regard to the similarity parti
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i \ ' 2.2. soz Emission and NOx Emi
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223
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Figure 9: Sulphur captLTre as 0 fun
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P SUMMARY OF TESTS Testing complete
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I Table 1 Comparison of Sulfur Capt
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, NITROGEN OXIDE REDUCTION Single-S
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0 The addition of air at the 96-inc
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m- Y i? 4: BO n 8 c Y l0- Bo- I I I
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E! w 2 z e Y 100 - 3 t 5 80- 0, 40
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0 f 0.so o'm: 0.300 0.zo - - A 5m 4
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&e- -A \ \ \ : ERCENT OVERBED AIR I
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PARTICLE ENTRAINMENT AND NITRIC OXI
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i 1' 1 ! I. i Chaung (15) showed th
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The maximum height that a large par
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3.0 Nitric Oxide Reduction in the F
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assumed to be identical to that of
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Nomenclature A *t cD ‘NO $3 _ _ _
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TABLE 2. OPERATING CONDITIONS AND E
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i 1 \ ', References 1. 2. ( 3. 1 4.
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\ ” Y) I 259
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t I 100 - - I I ] , I , I , I 'ii 9
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Feeding of the carbonaceous materia
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! Table 2 Proximate and ultimate an
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lb, , --pp---p-- 4 p? CHAR 1 Tu-IWO
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I CHAR Y Y /I TIME O i ' ' ' ' 1 '
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could not be assumed constant. Thus
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\ greatly acknowledged. Literature
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constructed and operated to demonst
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The experimental procedure for the
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atmospheric pressure fluidized bed
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1' TABLE 2 Screen Analysis of Sand
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n RECORDER I Ill I ’ NO. NOX THER
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\ 285 Y 0 I- 5 B 5 3 m "9 E5 3 uz 0
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CHAR1 TOC 0.85 M3/k 600 0 700 V 750
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f Durin all the experimental runs t
Page 291 and 292:
Assuming that large coal particles
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i 7 -_ 0 m\o --n 0 W i 293 a\o 0
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The influence of particle size dist
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all the initial values of x for whi
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\ - + 1) x. = 1 bL/n YO Defining di
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$ m. 1 Results and Discussion Evalu
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kl k2 k' KC KD m m. m P N P R R g t
Page 305 and 306:
UNBURNT FRACTION UNBURNT FRACTION m
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