condensation of zinc vapor on solid media in zn(g)-co-co2-ar mix.pdf

Condensation of Zinc Vapor on Solid Media in Zn(g)-CO-CO2-Ar Mixtures

N.X. FU, T. TAMAGAWA, M. KOBAYASHI, and M. TANAKA

The condensation experiments of zinc vapor on the solid media in Zn(g)-CO-CO2-Ar mixtures wereconducted in a flow reactor at 800 °C to 1000 °C under a zinc partial pressure of 0.6 to 7.9 kPa. Thecondensates were weighed, and the zinc contents and their morphology were analyzed to investigatethe effects of various factors on the condensation. It was found that the initial temperature of themedia should be as low as possible in liquid condensation for the efficient recovery of zinc. Thecondensation is enhanced with zinc partial pressure of the gases. The medium made of silica with asmooth surface is favorable for the efficient condensation. In the gases not oxidizing to zinc vapor,metallic zinc can be obtained on the medium with an initial temperature over the range of 120 °C to400 °C. For obtaining metallic zinc, it is necessary to raise the temperature of the gases, appropri-ately limit the zinc partial pressure, or maintain a sufficient CO/CO2 ratio to avoid the oxidation ofzinc vapor.

I. INTRODUCTION

CURRENTLY, the quantity of crude steel produced bythe electric arc furnace (EAF) approaches 30 million tonseach year in Japan, which amounts to about 30 pct of thetotal output of crude steel. At the same time, over 0.5 mil-lion tons of dust from the EAF exhaust gases are generatedannually.[1,2] The dust containing about 33 pct iron, 20 pctzinc, and small amounts of other valuable metals is con-sidered a significant resource. About 60 pct of the dust istreated via the processes of the Waelz kiln at 1100 °C andthe Mitsui furnace and electric distillation both at 1300 °C,in which zinc oxide is reduced by coke followed by theevaporation of zinc and the reoxidation of zinc vapor toproduce crude zinc oxide or zinc white with low commer-cial value.[3] These processes are complex and require alarge quantity of energy. Additionally, about 30 pct of thedust is disposed of by landfilling after stabilization, and10 pct is used as raw materials for cement. To save energyand minimize environmental load, a new process to recoveriron and metallic zinc with a yield of more than 80 pctdirectly from the EAF exhaust gases is being developedby the Japan Research and Development Center for Met-als (JRCM).[4,5] In this process, the hot exhaust gases froma sealed EAF are first treated by a moving coke bed filterto deposit iron, and second by a condenser to recover metal-lic zinc on falling ceramic balls with an average diameterof 0.5 mm.

Efficient condensation of zinc vapor as metallic zinc iscritical to the success of developing the process. The poten-tial for zinc vapor to be oxidized by CO2 on cooling obstructsthe acquisition of the metallic zinc. These are influencedby various factors including (1) temperature, flow rate, and

composition of the gases, and (2) initial temperature, material,and surface roughness of the condensation media. To furnishthe basis for the condenser design and the determinationof the optimum operational conditions, it is necessary toinvestigate the effects of these factors on the condensationprocess. For this purpose, the condensation experiments wereconducted in the present work by inserting the media intoZn(g)-CO-CO2-Ar mixtures in a flow reactor to condense zincvapor within a short time. The amounts of the condensateswere measured, and the zinc contents and their morphologywere analyzed.

II. THEORETICAL CONSIDERATIONS OF CONDENSATION

A. Condensation Efficiency

The equilibrium vapor pressure, , of zinc, as a func-tion of temperature,[6] is plotted in Figure 1. To condensea superheated vapor at a temperature of T0 and partial pres-sure of pi, it has to be cooled to a temperature below itsdew point, Td, at which saturation occurs. The condensateswill appear in the liquid and solid form at a temperatureabove and below 419 °C, respectively, which is the melt-ing point of zinc. The condensation efficiency of a con-denser in recovering liquid zinc from the mixtures of zincvapor with noncondensing gases depends on the zinc par-tial pressure and the condenser temperature, which can beunderstood by the theoretical percentage recovery, R,expressed as follows:[7]

[1]

where P is the total pressure, and pi and pf are zinc partialpressures in the incoming gases and the exhaust gases of thecondenser, respectively. This indicates that the condensationefficiency can be favored by reducing the dilution of thezinc vapor or the condenser temperature to decrease the zincpartial pressure at the exit.

R � 1 �pf (P � pi)

pi (P � pf)�

P (pi � pf)

pi(P � pf)� 100 pct

p0Zn

METALLURGICAL AND MATERIALS TRANSACTIONS B VOLUME 35B, AUGUST 2004—625

N.X. FU, Visiting Researcher, Metals Recovery Group, T. TAMAGAWA,Technical Staff Member, M. KOBAYASHI, Principal Research Scientist,and M. TANAKA, Group Leader, Metals Recovery Group, are with theResearch Institute for Green Technology, National Institute of AdvancedIndustrial Science and Technology (AIST), Ibaraki 305-8569, Japan. Contacte-mail: [email protected]

Manuscript submitted April 29, 2003.

03-03-221B-C.qxd 1/1/04 09:15 PM Page 625

626—VOLUME 35B, AUGUST 2004 METALLURGICAL AND MATERIALS TRANSACTIONS B

B. Oxidation of Zinc Vapor

When the mixtures of zinc vapor, CO, and CO2 are cooled,zinc vapor might be oxidized by the reaction

[2]

The occurrence of the oxidation depends on the CO2 con-tent, zinc partial pressure, and temperature of the gases,which can be understood in terms of the diagram of theequilibrium CO/CO2 ratio with the temperature shown inFigure 1.[7,8] Curve A1 (A2) gives the CO/CO2 ratio for Reac-tion [2] at the zinc partial pressure of 1.0 kPa (10 kPa). Ata given temperature, the mixtures at a CO/CO2 ratio belowcurve A1 (A2) are stable and will not form ZnO, but willtend to deposit ZnO above the curve. Evidently, the CO/CO2

ratio has to be correspondingly raised to avoid oxidationwhen the zinc partial pressure increases or the temperaturedecreases. Curve B represents the CO/CO2 ratio for the for-mation of ZnO from the mixtures in equilibrium with liquidzinc in the condensing temperature range. The CO/CO2 ratiohas to be kept above 5 � 103 to avoid ZnO formation oncondensation at 550 °C. However, the CO/CO2 ratio of theactual mixtures fed to the condenser is not so high. In thiscase, if the zinc vapor is condensed nearly at equilibriumconditions, one would find more zinc oxide than metalliczinc. Therefore, it is necessary to quench the mixtures withmedia at lower temperatures, thus condensing the zinc vaporwithout allowing time for the formation of zinc oxide.

Curve C gives the CO/CO2 ratio of the Boudouard reactionat a CO partial pressure of 50 kPa:

[3]

The mixtures with a CO/CO2 ratio above the curve tend toreact with solid carbon to reduce their CO2 content, but arestable in the absence of carbon. On the other hand, thosewith a CO/CO2 ratio below the curve tend to deposit carbonand thus to increase CO2. However, the carbon-depositionreaction is quite slow, so it does not constitute a practicalproblem.

CO2 � C � 2CO

Zn(g) � CO2 � ZnO � CO

III. EXPERIMENTAL METHOD

A. Apparatus

The apparatus for the condensation experiments consistedof a silica reactor tube with a 1330-mm length and a 45-mminner diameter horizontally placed in a furnace, as shown inFigure 2. The furnace was installed with heat elements inthree zones, which were separately controlled with a tem-perature regulator and a thermocouple to give the requiredtemperatures for the generation of zinc vapor, and the heat-ing and cooling of the gas mixtures. An inner silica tube witha 450-mm length and 35-mm diameter was mounted in theleft section of the reactor for zinc vaporization, in which argonwas introduced as the carrier gas, and a graphite boat chargedwith analytical-grade zinc ingots was initially placed in thelow-temperature side. The mixtures of CO and CO2 wereintroduced into the reactor through the gap between the reac-tor and the inner tube to mix with the zinc vapor in the heat-ing zone. Fiber blocks with some small holes were set in theoutlet of the inner tube and the passage of CO-CO2 to avoidthe backward diffusion of the gas mixtures causing oxida-tion of the zinc vapor. Another inner silica tube was mountedin the right section of the reactor, in which a silica tube withan outer diameter of 20 mm and a length of 600 mm as a con-densation medium was located in the low-temperature side inadvance, and counterflow nitrogen was introduced to avoidundesired condensation. In that place, the surface tempera-ture at the front end of the medium was determined as theinitial temperature of the medium (ITM), which was changedby its location.

To compare the condensation on the media made of differ-ent materials, small disks of silica, alumina, and graphitewith 10-mm diameter and 1-mm thickness were employed,which were attached to the condensation tube by a graphiteholder. To compare the condensation on the media withdifferent surface roughness, an ordinary silica tube and asatin-finish one were also used with the same outer dia-meter of 20 mm, wall thickness of 1.7 mm, and a length of600 mm. Additionally, a short silica cap with a 21-mm innerdiameter and 30-mm length was also used as a mediumsheathing the front end of the condensation tube to favorthe more accurate measurement of the weight of the con-densates for determining their zinc contents. The surfacetemperatures of the media in the reactor were measured byan infrared thermometer in independent experiments in nitro-gen to approximately simulate those in the condensationexperiments.

Fig. 1—Equilibrium vapor pressures of zinc and CO/CO2 ratios as a func-tion of temperature in Zn(g)-CO-CO2 gases at one atmosphere. Fig. 2—Apparatus for condensation experiments.

03-03-221B-C.qxd 1/1/04 09:15 PM Page 626


B. Procedure and Conditions

Argon, CO-CO2, and nitrogen were introduced into the sys-tem at appropriate flow rates during the heating of the reactor.After reaching the required temperatures in the reactor, theboat was pushed to the predetermined place to start the vapor-ization of zinc, where the temperature was measured by athermocouple. Passing through the heating zone, Zn(g)-CO-CO2-Ar gases were further heated to 800 °C to 1000 °C. Afterinterrupting the flow of nitrogen, the medium was quicklyinserted into the gases at high temperature to condense zincvapor within a given time and then immediately withdrawnto a low-temperature place for rapid cooling followed by therestoration of nitrogen. The boat was also withdrawn to theoriginal position for cooling. After removing the mediumfrom the reactor, the medium was weighed together withthe condensates by an electronic balance with a sensitivityof 0.1 or 1 mg depending on the known weight of themedium, which was subtracted from their total weight toobtain that of the condensates. The morphology of the conden-sates was observed by a microscope, and the zinc contents weredetermined by an EDTA titration method.

The vaporization rate of the zinc measured using theweight-loss method[9] was controlled by changing the tem-perature and the area of the boat. The experiments of sup-plying Zn(g)-CO-CO2-Ar gases for the condensation werecarried out previously. The partial pressure of the zinc vaporin the supplied gases was calculated by the vaporizationrate of the zinc and the flow rates of the CO-CO2-Ar gases.All the conditions for the condensation experiments are sum-marized in Table I. The calculated zinc partial pressure wasused to indicate the actual one, since the zinc vapor was notoxidized in the gases in most cases. In experiment F at 800 °C,G, and H, the oxidation of zinc vapor occurred to some extentdue to lower temperature or smaller CO/CO2 ratio; thus, theactual zinc partial pressure would be lower than the calcu-lated value.

IV. RESULTS AND DISCUSSION

A. Effects of Various Factors on the Quantity of the Condensates

1. Initial temperature of mediumExperiment A involved the condensation within 5 seconds

at 900 °C to 1000 °C at different ITMs. Figure 3 shows thatthe amounts of the condensates increase with the lowering

of the ITM from 450 °C to 250 °C to 300 °C, while they grad-ually decrease thereafter down to about 150 °C. It was con-firmed that the temperature of the medium quickly increasedwith time after it reached the high-temperature zone andreached a larger value by employing a higher ITM. In theITM between 250 °C and 450 °C, the zinc vapor condensedas a liquid; thus, the decrease in the temperature of themedium by reducing ITM was favorable for obtaining morecondensates. In the ITM between 150 °C and 250 °C, thecondensates appeared as a solid. Thus, the condensatesdecreased by lowering the ITM, probably because some finesolid particles of the condensates formed in a thermal bound-ary layer around the medium and were partly carried awaywith the gases. These results indicate that the ITM should beas low as possible under the liquid condensation to obtainmore condensates in a given time.

2. Flow rate and zinc partial pressureIn experiment B, the condensation was carried out within

10 to 30 seconds at 1000 °C by varying the flow rate of thegases from 925 to 2510 mL/min at the same zinc partialpressure. The changes in the amounts of the condensates asa function of time are given in Figure 4, showing that thecondensates obtained within the same time generally increaseby raising the flow rate corresponding to the enhancementof the mass transfer of the zinc vapor. However, it was foundthat the percentage of the condensation, defined as the ratioof the amount of the condensate to that of the feed zinc forthe same duration, gradually decreased with the flow rate.

Table I. Conditions for the Condensation Experiments

Series of Experiments , mL/min FCO�CO2

mL/min pZn, kPa CO/CO2 Ratio T, °C ITM, °C Medium

A 34 800 2.6 7 900 to 1000 150 to 450 capB 72 to 195 353 to 1815 7.9 9 1000 225 tubeC 34 to 110 800 2.6, 5.3, 7.9 9 1000 330 tubeD 34 800 2.6 9 1000 180 to 500 disksE 34 800 2.6 9 1000 150 to 545 tubesF 8 800 0.6 3.5 800 to 900 120 to 400 capG 8, 13, 22 800 0.6, 1.0, 1.7 3.5 800 300 capH 22 800 1.7 3.5 to 9 800 300 cap

*With a flow rate of argon: 500 mL/min; VZn: vaporization rate of zinc; FCO�CO2: flow rate of CO � CO2; pZn: calculated zinc partial pressure; T: gas

temperature; ITM: initial temperature of medium; cap: short silica cap; tube: silica tube; and disks: small disks of silica, alumina, and graphite.

VZn*

Fig. 3—Amounts of condensates as a function of ITM, PZn � 2.6 kPa, CO/CO2 � 7, time: 5 s.

03-03-221B-C.qxd 1/1/04 09:15 PM Page 627


Fig. 4—Amounts of condensates for different condensation times with vary-ing flow rates of gases at 1000 °C.

Fig. 5—Amounts of condensates with the condensation time under differ-ent partial pressures of zinc at 1000 °C.

Fig. 6—Amounts of condensates on different media by varying their ini-tial temperatures.

This is probably due to the increase in the temperature ofthe medium with the flow rate, because more latent heat wasreleased during the condensation, and the coefficient of con-vective heat transfer between the surface of the medium andthe gases could become larger. These facts imply that thefeed rate of the medium should be raised with the flow ratein the practical operation of the condenser to maintain highcondensation efficiency.

In experiment C, the condensation within 10 to 30 secondswas performed at 1000 °C by varying the zinc partial pressurefrom 2.6 to 7.9 kPa at the same flow rate of the CO-CO2-Argases. The amounts of the condensates with time, presentedin Figure 5, indicate that there were always more condensatesat a higher zinc partial pressure than at a lower one for the sametime. This is consistent with the fact that the supersaturationof zinc vapor increases with its partial pressure at a given tem-perature to give a larger driving force for the condensation.[10]

3. Materials and surface roughness of the mediaThe condensation on the disks of silica, alumina, and gra-

phite was compared in experiment D. The amounts of thecondensates within 5 seconds with the ITM over the range180 °C to 500 °C are shown in Figure 6. The data seem toscatter because the time taken for inserting the disks intothe gases at high temperature was not identical for the dif-ferent runs due to the limitation of the operating conditions.However, it can be seen that the condensates on the silicadisks are generally about 0.2 to 1.5 mg more than those onthe alumina ones, while those on the graphite ones are muchless. It was observed that the condensates mostly formed asliquid droplets, and those on the silica disks were muchplumper and denser than those on the alumina ones, as shownin Figure 7. When the ITM was about 180 °C, additionally,it was found that the condensates appeared as solid particlesin the lower left section of the silica disk and as liquid dropletsin the rest, while those formed on the alumina disk were allfine liquid droplets (Figures 8(a) and (b)). These findingsshow that the temperatures of the silica disks would be some-what lower than those of the alumina ones during the con-densation. This was probably caused by a difference in theheat conduction between the silica disks and alumina onesdue to their different physical parameters such as the ther-mal conductivity, specific heat, and density (Table II[11,12,13]).As a result, more condensates were obtained on the silica

disks than on the alumina. Relative to the silica and alu-mina disks, the temperatures of the graphite disks wouldbecome much higher in the gases at high temperature dueto smaller specific heat and density of graphite (Table II),which made the condensation very difficult.

Fig. 7—Droplets of condensates on silica disk (upper half) and on aluminadisk (lower half), initial temperature of medium: 340 °C.

03-03-221B-C.qxd 1/1/04 09:15 PM Page 628


The comparisons between the condensation on the silicamedia with smooth and rough surfaces were made in experi-ment E. The changes in the amounts of the condensates withIMT and condensation time are shown in Figure 9. On thesmooth medium, there were about 1 to 4 mg more conden-sates than on the rough one depending on the IMT and thecondensation time, except for the results with a high IMT of545 °C or a short time of 1 second. In the case of liquid con-densation, moreover, the droplets on the smooth mediummostly were even in size and dense in distribution, while thoseon the rough one were uneven and relatively dispersed. Thesemay be attributed to the fact that the temperature of the roughmedium would be higher than that of the smooth one duringthe condensation, since more radiation energy is probablyabsorbed by the former than by the latter due to less absorp-tivity of the smooth surface.[14]

Fig. 8—(a) Solid particles with a few droplets of condensates on silica diskand (b) droplets of condensates on alumina disk. Initial temperature ofmedium: 180 °C.

Table II. Physical Constants of the DifferentMaterials (200 °C to 600 °C)

Thermal Conductivity Specific Heat Density

Materials W/(m � °C) kJ/(kg � °C) g/cm3

Silica 1.32 to 1.98 0.86 to 1.13 3.94Alumina 4.67 to 6.92 1.05 to 1.17 3.88Graphite 93.44 to 154.01 0.79 1.56

Fig. 9—Amounts of condensates on silica media with different surface con-ditions as a function of ITM and condensation time.

B. Effects of Several Factors on the Qualityof the Condensates

1. Gas temperature and ITMIn experiment F, the condensation was conducted at 800 °C

to 900 °C within 5 seconds at the zinc partial pressure of0.6 kPa and the CO/CO2 ratio of 3.5. The ITM was variedfrom 120 °C to 400 °C to change the cooling rate of thegases. The zinc contents of the condensates are presented inFigure 10 and compared with those of the condensatesobtained in experiment A shown in Figure 11. Those ofalmost all the condensates were approximately 100 pct inthe two experiments at 900 °C to 1000 °C, at which the feedgases were not oxidizing to the zinc vapor. This shows thatthe medium with the ITM ranging up to at least 400 °Ccaused a sufficient cooling rate of the gases to avoid the oxi-dation of the zinc vapor during the condensation on it; thus,metallic zinc was obtained. In experiment F at 800 °C, thegases were oxidizing to zinc vapor by CO2

[15–19] due to thelower temperature and smaller CO/CO2 ratio. Although thezinc contents of some condensates approached 100 pct, thoseof others were obviously lower than this limit, indicatingthat they contained small amounts of zinc oxide. Since thepossibility of the oxidation of zinc vapor on the medium isexcluded due to its cooling role on the gases, zinc oxide inthe condensates probably results from the partial deposi-tion of that formed in the gases because of the oxidation ofzinc vapor on the existing solid fine particles, which prob-ably dropped from the fiber blocks in the outlet of the vapor-ization tube.

2. Partial pressure of zinc vaporIn experiment G, the condensation was conducted at 800 °C

within 5 seconds by varying the zinc partial pressure from0.6 to 1.7 kPa at a CO/CO2 ratio of 3.5. The zinc contentsof the condensates are compared in Figure 12 at the ITMof 300 °C. Those are more than 95 pct at 0.6 kPa, but lessthan 90 pct at 1.0 and 1.7 kPa, showing a tendency that thezinc contents of the condensates decrease with the partialpressure of zinc. The gases were oxidizing to the zinc vaporunder these conditions, which is the reason for the existence

03-03-221B-C.qxd 1/1/04 09:15 PM Page 629


Fig. 11—Zinc contents of condensates with varying initial temperaturesof medium, PZn � 2.6 kPa, CO/CO2 � 7.

of zinc oxide in the condensates, as previously mentioned. Thus,the decrease in the zinc content of the condensates with thepartial pressure of zinc may be attributed to the fact thatthe oxidation extent of the zinc vapor increases with the par-tial pressure of zinc when the temperature and CO/CO2 ratioare given.[16,17]

3. CO/CO2 ratioThe condensation was carried out at 800 °C within 5 seconds

with varying CO/CO2 ratio from 3.5 to 9 in experiment H.Figure 13 shows that the zinc contents of the condensatesincreased with the rise in the CO/CO2 ratio. They were lowerthan 90 pct at lower CO/CO2 ratios up to 5, but tended tobe 100 pct thereafter. These results demonstrate that the con-densates obtained at lower CO/CO2 ratios contained partialzinc oxide formed in the gases, and there was a trend toobtain metallic zinc by raising the CO/CO2 ratio up to 9. Thisis attributed to the fact that the oxidation potential of the zincvapor increases with the lowering of CO/CO2 ratio or raisingCO2 content in the gases.[7,9] Therefore, the CO/CO2 ratiohas to be maintained above a limit under the given conditions;otherwise, the oxidation of zinc vapor would occur to reducethe zinc content of the condensates. This limit would behigher for the gases at lower temperature or higher zinc partialpressure, as shown in Figure 1.

V. CONCLUSIONS

The condensates increased by lowering the ITM on theliquid condensation, and decreased by further reducing that onthe solid condensation due to partial losses of the solid parti-cles with the outlet gases. The ITM should be as low as pos-sible for efficient condensation in the liquid form. Althoughthe condensates increased with the flow rate of the gases dueto the enhancment of the mass transfer, the percentage of thecondensation simultaneously decreased. This suggests that thefeed rate of the medium should be raised with the flow rateto gain condensation efficiency in the practical operation onthe condenser. The condensates increased with the zinc par-tial pressure because of the increased supersaturation of thezinc vapor at a given temperature.

The materials of the media affect the amounts of the con-densates due to their different heat conductivities, which arerelated to their thermal conductivity, specific heat, and den-sity. Silica appears to be preferable to alumina as a mediumfor efficient condensation. In addition, it was confirmed thatthe medium with a smooth surface is more favorable to thecondensation than one with a rough surface because of theirdifferent absorption properties of radiation energy.

The medium with the ITM over a broad range from 120 °Cto at least 400 °C could cause a sufficient cooling rate of the

Fig. 12—Zinc contents of condensates with varying partial pressures ofzinc, CO/CO2 � 3.5, ITM � 300 °C.

Fig. 13—Zinc contents of condensates as a function of CO/CO2 ratio inthe gases at 800 °C.

Fig. 10—Zinc contents of condensates with varying initial temperaturesof medium, PZn � 0.6 kPa, CO/CO2 � 3.5.

03-03-221B-C.qxd 1/1/04 09:15 PM 30


gases to prevent the oxidation of zinc vapor during the conden-sation on it. When the feed gases were oxidizing to zinc vapor,zinc oxide arose on some fine particles in the gas stream anddeposited with the condensates on the medium. To obtainmetallic zinc, it is essential to avoid the oxidation of zincvapor in the gases. The zinc contents of the condensatesincreased by raising the temperature of the gases, loweringthe partial pressure of zinc vapor, or increasing the CO/CO2

ratio to reduce the oxidation tendency of the zinc vapor. It issuggested that we have a combined control of these parametersaccording to the actual conditions for obtaining metallic zinc.

ACKNOWLEDGMENTS

The authors are grateful to the New Energy and IndustrialTechnology Development Organization (NEDO) for the finan-cial support for this work. We carried out the present workas participants on the project “Technology for Energy-SavingRecovery of Metallic Dust” organized by JRCM.

REFERENCES1. H. Sasamoto and T. Furukawa: Proc. 6th Int. Symp. on East Asian

Resources Recycling Technology, Gyeongju, Korea, Oct. 23–25, 2001,Program Committee, ed., The Korean Institute of Resources Recycling,Korea Environment Institute, Seoul, Korea, pp. 9-17.

2. T. Furukawa and H. Sasamoto: Proc. 6th Int. Symp. on East AsianResources Recycling Technology, Gyeongju, Korea, Oct. 23–25, 2001,Program Committee, ed., The Korean Institute of Resources Recycling,Korea Environment Institute, Seoul, Korea, pp. 393-97.

3. M. Shima and S. Kawakita: J. Min. Mater. Processing Inst. Jpn., 1991,vol. 107, pp. 85-94.

4. S. Sato: J. Min. Mater. Processing Inst. Jpn., 1999, vol. 115, pp. 484-85.5. M. Yasui and H. Sasamoto: Proc. 21st Int. ATS Steelmaking Conf., Paris,

France, Dec., 2000, ATS (The French Steel Technical Association),pp. 214-15.

6. O. Kubaschewski: Metallurgical Thermochemistry, Pergamon Press,Ltd., London, 1956, p. 330.

7. C.H. Mathewson: Zinc: The Metal. Its Alloys and Compounds, ReinholdPublishing Co., New York, NY, 1959, pp. 79-95.

8. T. Rosenqvist: Principles of Extractive Metallurgy, McGraw-Hill BookCo., New York, NY, 1974, p. 307.

9. T. Tamagawa, M. Kobayashi, and N.X. Fu: Proc. TMS Annual Meeting,New Orleans, LA, Feb. 11–15, 2001; EPD Congress 2001, P.R. Taylor,ed., TMS, Warrendale, PA, pp. 195-201.

10. J.P. Hirth: in Vapor Deposition, Carroll F. Powell, ed., John Wiley &Sons, New York, NY, 1966, pp. 126-33.

11. International Critical Tables of Numerical Data Physics, Chemistryand Technology, E.W. Washburn, ed., McGraw-Hill Book Co., NewYork, NY, 1928, vols. II, III, and V.

12. Handbook of Heat Transfer, W.M. Rohsenow and J.P. Hartnett, eds.,McGraw-Hill Book Co., New York, NY, 1973, pp. 2-71.

13. Max Jakob: Heat Transfer, John Wiley & Sons, New York, NY, 1949,pp. 95-98 and 278-83.

14. Hoyt C. Hottel: Radiative Transfer, McGraw-Hill Book Co., New York,NY, 1967, pp. 140-45.

15. P.M.J. Gray and S.E. Woods: Proc. 9th Commonwealth Mining andMetallurgical Congr., M.J. Jones, ed., Institute of Mining and Metal-lurgy, London, 1970, vol. 3, pp. 872-75.

16. F. Noguchi and T. Nakamura: J. Min. Mater. Processing Inst. Jpn.,1995, vol. 111, pp. 181-85.

17. J.A. Clarke and D.J. Fray: Trans. Inst. Min. Metall., Sect. C, 1982,vol. 91, pp. C26-C31.

18. L.A. Lewis and A.N. Cameron: Metall. Mater. Trans. B, 1995, vol. 26B,pp. 911-18.

19. J.M. Osborne, W.J. Rankin, D.J. McCarthy, and D.R. Swinbourne:Metall. Mater. Trans. B, 2001, vol. 32B, pp. 37-45.

03-03-221B-C.qxd 1/1/04 09:15 PM Page 631

condensation of zinc vapor on solid media in zn(g)-co-co2-ar mix.pdf

Documents