LABORATORY OF INORGANIC MATERIALS

Mathematical modeling using

a Computed Fluid Dynamics (CFD)

simulation to calculate the velocity

and temperature distribution in the

melting space.

Quantitative evaluation of the main

melting processes in a continuous

melting space.

The behavior of bubbles in the vis-

cous fl uid under the action of cen-

trifugal force.

MAIN RESEARCH SUBJECTS

Optimization of the glass melting

process by infl uencing the course

of the chemical reaction to sulphur

compounds.

Corrosion of refractories by molten

glasses.

The development of new types of

glasses, eliminating heavy metal

oxides, particularly lead and barium.

Preparation and development of

special glasses for photonics.

THEMATIC RESEARCH FOCUS

MELTING PROCESSES AND

THEIR MODELING

CHEMICAL REACTIONS DURING

GLASS MELTING

THE DEVELOPMENT OF NEW

TYPES OF GLASSES

MATERIALS FOR PHOTONICS

AND OPTOELECTRONICS

The Laboratory of Inorganic Materi-

als is a successor for the Laboratory

of Chemistry and Technology of Sili-

cates of the Czechoslovak Academy

of Sciences and Institute of Chemi-

cal Technology, Prague, founded in

1961. In 2012, the laboratory was

transformed into a joint workplace

of the Institute of Chemical Tech-

nology, Prague and the Institute

of Rock Structure and Mechanics

ASCR, v. v. i.

Temperature distribution in the melting space on the top melt level

INSTITUTE OF ROCK STRUCTURE AND MECHANICS of the Czech Academy of Sciences

KEY RESEARCH EQUIPMENTSPreparation of glasses

under defi ned conditions

Visual observation and image

analysis processes in glass melts

Determination of the solubility

of gases in the melts (GC-MS)

Analysis of the evolved gases (EGA)

Determination of the oxygen partial

pressure in glass melts

Thermal analysis (DTA / TG / DSC)

Polarizing microscopy

Measurement of glass absorption

in the UV / VIS and IR regions

C/SO42- = 0.5

0

20

40

60

80

100

120

140

160

180

200

220

240

260

200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600

Temperature (oC)

CO

, O2,

SO2 (

μl/g

)

0

200

400

600

800

1000

1200

1400

1600

1800

2000

2200

2400

2600

CO

2 (μl

/g)

CO/12

O2/32

SO2/64

CO2/44

( )2 24 2 2

o

2 ( ) 2 (g) + (g) + 2 ( )

1200 1500 C

SO l SO O O l− −↔

−

( )24

22

( ) + 4 ( )

4 ( ) + ( ) 800 1050 oSO l CO g

CO g S l C

−

−

↔

−

( )

24

22 2

( ) + ( ) ( ) + ( ) + ( )

1000 1100 o

SO l CO gCO g SO g O l

C

−

−

↔

−

( )2 24

22 4 ( ) + 4 ( ) 1100 1200 oSO g O l C

− −

−

3 ( ) + ( ) SO l S l ↔

−

High temperature observation furnace Bubble size measured by image analysis

Evolved gas analysis of glass batch containing sodium sulphate and carbon

Crucible with refractory material corroded by glass melt

Laboratory furnaces for glass preparation

Nucleation of bubbles on Pt wire

Glass melting processes - Experimental observation of bubble sources

Change of the mechanism

gas insoluble,

glass saturated

gas well soluble,

glass under-saturated

bubble is centrifuged bubble disssolves

high pressures

1200

800

400

00 50 100 150 200

τF [s]

ω [rad/s]

The effect of rotational velocity on bubble removal time.

ACHIEVEMENTS

Glass melting processesL. Němec, P. Cincibusová, 2009. Glass melting and its innovation potentials: The potential role of glass fl ow in the sand-dissolution process. Ceramics-Silikáty 53, 145–155.

M. Polák, L. Němec, 2011. Glass melting and its innovation potentials: The combination of transversal and longitudinal circulations and its infl uence on space utilisation. Journal of Non-Crystalline Solids 357, 3108–3116.

M. Jebavá, L. Němec, 2011. Bubble removal from glass melts with slow vertical circulations. Ceramics-Silikáty 55, 232–239.

M. Polák, L. Němec, 2012. Mathematical model-ling of sand dissolution in a glass melting chan-nel with controlled glass fl ow. Journal of Non-Crystalline Solids 358, 1210–1216.

P. Cincibusová, L. Němec, 2012. Sand dissolu-tion and bubble removal in a model glass-melt-ing channel with a melt circulation. Glass Tech-nology: European Journal of Glass Science and Technology, Part A 53, 150–157.

L. Němec, P. Cincibusová, 2012. Sand disso-lution and bubble removal in a model glass-melting channel with a uniform melt fl ow. Glass Technology: European Journal of Glass Science and Technology, Part A 53, 279–286.

M. Jebavá, L. Němec, 2012. The fi ning perform-ance under the eff ect of physico-chemical pa-rameters. Ceramics-Silikáty 56, 286–293.

L. Němec, M. Vernerová, P. Cincibusová, M. Jebavá, J. Kloužek, 2012. The semiempirical model of the multicomponent bubble behaviour in glass melts. Ceramics-Silikáty 56, 367–373.

M. Jebavá, L. Němec, 2013. Numerical study of glass fi ning in a pot melting space with diff erent melt-fl ow patterns. Journal of Non-Crystalline Solids 361, 47–56.

L. Němec, M. Jebavá, P. Dyrčíková, 2013. Glass melting phenomena, their ordering, and melt-ing space utilisation. Ceramics-Silikáty 57, 275–284.

New melting concepts

V. Tonarová, L. Němec, M. Jebavá, 2010. Bubble removal from glass melts in a rotating cylinder. Glass Technology: European Journal of Glass Science and Technology, Part A 51, 165–171.

V. Tonarová, L. Němec, J. Kloužek, 2011. The op-timal parameters of bubble centrifuging in glass melts. Journal of Non-Crystalline Solids 357, 3785–3790.

L. Němec, J. Kloužek, V. Tonarová, M. Jebavá, 2013. The method of glass fi ning by centrifug-ing. Patent No. CZ 304044.

L. Němec, J. Kloužek, V. Tonarová, M. Jebavá, 2014. The device for glass-melt fi ning by centri-fuging. Patent No. CZ 304299.

Development of new types of glassesJ. Kloužek, L. Němec, J. Tesař, M. Hřebíček, K. Kaiser, 2010. Ruby glass coloured by gold. Patent No. CZ 302143.

J. Kloužek, L. Němec, J. Tesař, M. Hřebíček, K. Kaiser, 2010. Crystal glass without content of lead and baryum compound. Patent No. CZ 302142.

Longitudional section of glass melting space

TEM micrograph of gold nanoparticles in ruby glass.

J. Kloužek, L. Němec, J. Tesař, M. Hřebíček, K. Kaiser, 2010. Coloured glasses without con-tent of lead and baryum compound. Patent No. CZ 302144.

J. Kloužek, M. Polák, M. Hřebíček, K. Kaiser, V. Tonarová, 2011. Crystal non-lead and non-baryum glass with content of lanthanum and niobium oxides. Utility model No. CZ 22399.

J. Kloužek, M. Polák, M. Hřebíček, K. Kaiser, V. Tonarová, 2012. Crystal non-lead and non-baryum glass with content of lanthanum and niobium oxides. Patent No. CZ 303117.

MAIN COLLABORATING PARTNERS

– Institute of Chemical Technology, (Prague, Czech Republic)

– International Partners in Glass Research, (Switzerland)

– Glass Service B.V., (Netherland)

– Asahi Glass Co., Ltd., (Japan)

– Slovak Technical University, (Slovakia)

– UMR 6226, Université de Rennes 1, (France)

– Technical University Istanbul, (Turkey)

– Harran University, Sanliurfa, (Turkey)

– Preciosa a.s., (Czech Republic)

Laboratory of Inorganic Materials

V Holešovičkách 41182 09 Praha 8Czech Republicwww.irsm.cas.cz/materials

Doc. Ing. Jaroslav Kloužek, CSc. Head of Laboratory of Inorganic Materials E-mail: jaroslav.klouzek@irsm.cas.cz Phone: +420 266 009 422

J. Zavadil, P. Kostka, J. Pedlíková, ZG. Ivanova, K. Žďánský, 2010. Investigation of Ge based chalcogenide glasses doped with Er, Pr and Ho. Journal of Non-Crystalline Solids 356, 2355–2359.

J. Macháček, P. Kostka, M. Liška, J. Zavadil, O. Gedeon, 2011. Calculation and analysis of vibrational spectra of PbCl2–Sb2O3–TeO2 glass from fi rst principles. Journal of Non-Crystalline Solids 357, 2562–2570.

P. Kostka, J. Zavadil, J. Pedlíková, M. Poulain, 2011. Preparation and optical characterization of PbCl2–Sb2O3–TeO2 glasses doped with rare earth elements. Physica Status Solidi A – Appli-cation and Materials Science 208, 1821–1826.

J. Zavadil, M. Kubliha, P. Kostka, M. Iovu, V. Labas, Z.G. Ivanova, 2013. Investigation of electrical and optical properties of Ge–Ga–As–S glasses doped with rare-earth ions. Journal of Non-Crystalline Solids 377 (SI), 85–89.

O. Bošák, P. Kostka, S. Minárik, V. Trnovcová, J. Podolinčiaková, J. Zavadil, 2013. Infl uence of composition and preparation conditions on some physical properties of TeO2–Sb2O3–PbCl2 glasses. Journal of Non-Crystalline Solids 377 (SI), 74–78.

M. Kubliha, P. Kostka, V. Trnovcová, J. Zavadil, J. Bednarčík, V. Labaš, J. Pedlíková, A. C. Dippel, H.P. Liermann, J. Psota, 2014. Local atomic struc-ture and electric properties of Ge20Se80-xTex (x=0, 5, 10 and 15) glasses doped with Ho. Jour-nal of Alloys and Compounds 586, 308–313.

Snapshot of the 3D structure of the ZnBr2-Sb2O3 glass modeled by using FP MD. Colour legend: Sb (violet), Zn (green), O (red), Br (brown).

MASS PERFORMANCE

FLUX OF HEAT LOSSES

500

450

400

350

300

250

200

150

100

50

00 0,2 0,4 0,6 0,8 1 1,2

THE FRACTION OF ENERGY APPLIED TO PROMOTE THE HELICAL FLOW

THE

MA

SS

PER

FOR

MA

NC

E O

F TH

E G

LAS

S

MEL

TIN

G S

PA

CE

IN t/

day

AN

D T

HE

FLU

X O

F H

EAT

LOS

SES

IN k

J/s

The cross section through the model-led glass melting space showing the arisen helical fl ow of the melt which allows the high melting per-formance and restricts heat los-ses of the melting space.

The increasing mass performance and decreasing fl ux of heat losses as a function of energy transferred to promote the helical melt fl ow.

Materials for photonics and opto-electronics

J. Zavadil, P. Kostka, J. Pedlíková, K. Ždanský, M. Kubliha, V. Labaš, J. Kalužný, 2009. Electro-optical characterization of Ge–Se–Te glasses. Journal of Non-Crystalline Solids 355, 2083–2087.

J. Kalužný, J. Pedlíková, J. Zavadil, M. Kubliha, V. Labaš, P. Kostka, 2009. Electrical methods for optimization of structural changes and defects in sulphide glasses. Journal of Optoelectronics and Advanced Materials 11, 2053–2057.

J. Kalužný, J. Pedlíková, J. Zavadil, M. Kubliha, V. Labaš, P. Kostka, 2009. Investigation of elec-trical and dielectric properties of Ge20Se80-xTex glasses doped by Er, Ho, Pr. Journal of Optoelec-tronics and Advanced Materials 11, 2063–2068.

INSTITUTE OF ROCK STRUCTURE AND MECHANICS of the Czech Academy of Sciences