Drying out and Heating up of refractory installations in the cement

industry

Dirk Basten

Refratechnik Cement Supervisor Training Course 2012

Refractory installation

of a complete plant

static

predominantly castable

dynamic

predominantly bricks

Scheme of the refractory installation of a complete plant

static

predominantly castable

Water sources physically bonded water

Installation of wet bricks Strictly follow guidelines

Avoid leaking water

0100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

0 12 24 36 48 60 72 84 96 108 120 132 144 156 168

t [h]

T [C]

approx 13 K/h

approx 10 K/h

approx 30 K/h

approx 10 K/h

TrocknungTrocknungTrocknungTrocknung AufheizenAufheizenAufheizenAufheizen

Anmerkungen: Genere ll sollt e vor dem Beginn de r Trocknung und des Aufhe izens e in mindestens 24 stndiges Aushrten der Masse stat tgefunden haben!

1* > Ofendrehung 180 a lle 45 minutes - Re fe renzmante lt empera tur in de r Brennzone ca . 100 - 150C

2* > Ofendrehung 90 a lle 30 minutes - Referenzmante lt emperatur burning zone ca .. 200 - 235C

3* > Ofendrehung kont inuie rlich - Referenzmante lt empe ratur burning zone ca . 260 - 310C

* t heoret ica l ca lculated she ll t emperature - depends on environment condit ions

1*

2*

3*

Entfernen der

Abdichtungen / Start des

Hauptbrenners

850C -1000C

Inbetriebnahme

Typical dry out curve for complete new plant

Aufheizdiagramm feuerfester Massen (LCC, MCC, SC, JC)

Heating diagramm of refractory concretes (LCC, MCC, SC, JC)

0

100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

1500

0 10 20 30 40 50 60 70 80 90 100 110

Zeit nach Einbau / h

Time after installation / hrs

T

e

m

p

e

r

a

t

u

r

/

C

T

e

m

p

e

r

a

t

u

r

e

/

C

10 h / 500 C

min. 24 h Erhrtungsdauer

min. 24 hrs setting time

20 h / 110 - 150 C

15 C/h

25 C/h

30 C/h

bis zur Einsatztemperatur

up to temp. of application

Heating Up

Drying

Time after installation / hTime after installation / hTime after installation / hTime after installation / h

Heating diagram of refractory concretesHeating diagram of refractory concretesHeating diagram of refractory concretesHeating diagram of refractory concretes

Heating diagram of refractory concretes (AR, LCC, SC, JC, G, Heating diagram of refractory concretes (AR, LCC, SC, JC, G, Heating diagram of refractory concretes (AR, LCC, SC, JC, G, Heating diagram of refractory concretes (AR, LCC, SC, JC, G,

MCG, LCG) Stationary areas wall thickness 50MCG, LCG) Stationary areas wall thickness 50MCG, LCG) Stationary areas wall thickness 50MCG, LCG) Stationary areas wall thickness 50---- 300 mm300 mm300 mm300 mm

Behaviour of drying rate

as a function of drying time

0

10

20

30

40

50

60

70

80

90

100

1 2 3 4 5 6 7 8 9 10 11 12 13

Dryiing time

D

r

y

i

n

g

r

a

t

e

Drying time [h]Drying time [h]Drying time [h]Drying time [h]

D

r

y

i

n

g

r

a

t

e

[

q

u

a

n

t

i

t

y

/

h

]

D

r

y

i

n

g

r

a

t

e

[

q

u

a

n

t

i

t

y

/

h

]

D

r

y

i

n

g

r

a

t

e

[

q

u

a

n

t

i

t

y

/

h

]

D

r

y

i

n

g

r

a

t

e

[

q

u

a

n

t

i

t

y

/

h

]

Drying rate as a function of timeDrying rate as a function of timeDrying rate as a function of timeDrying rate as a function of time

tkn

Phase 1Phase 1Phase 1Phase 1

continous drying

rate

Phase 2Phase 2Phase 2Phase 2

Decreasing drying rate

Low vapour pressurelow drying rate

Ppore openingPmeniskus >Phase 1:

outletInletair

100100100100CCCC

/1 bar/1 bar/1 bar/1 bar

20202020CCCC

/0.02 bar/0.02 bar/0.02 bar/0.02 bar

T [C]

Ppore opening

Pcapillary

PmeniskusP 1 bar

Low temperatur, continous airstream with high ventilation

Ppore opening

Pcapillary

Pmeniscus

T [C]

OutletInletAir stream

350350350350CCCC

/165 bar/165 bar/165 bar/165 bar

100100100100CCCC

/1 bar/1 bar/1 bar/1 bar

< Ppore openingPMeniskusPhase 2:

P 164 bar

High temperature, low ventilation and airstreamHigh temperature, low ventilation and airstreamHigh temperature, low ventilation and airstreamHigh temperature, low ventilation and airstream

Pressure- and temperatur gradient in a to be dried refractory body

(Dissertation: Modell zur Beschreibung der Trocknung von Feuerbetonen, Ingo Growendt, 2007, p.25)

0

50

100

150

200

250

0 50 100 150 200 250 300 350 400

T empe r a t ur e (C )T empe r a t ur e (C )T empe r a t ur e (C )T empe r a t ur e (C )

S

a

t

u

r

a

t

i

o

n

v

a

p

o

u

r

p

r

e

s

s

u

r

e

(

b

a

r

)

S

a

t

u

r

a

t

i

o

n

v

a

p

o

u

r

p

r

e

s

s

u

r

e

(

b

a

r

)

S

a

t

u

r

a

t

i

o

n

v

a

p

o

u

r

p

r

e

s

s

u

r

e

(

b

a

r

)

S

a

t

u

r

a

t

i

o

n

v

a

p

o

u

r

p

r

e

s

s

u

r

e

(

b

a

r

)

Aufheizdiagramm feuerfester Massen (LCC, MCC, SC, JC)

Heating diagramm of refractory concretes (LCC, MCC, SC, JC)

0

100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

1500

0 10 20 30 40 50 60 70 80 90 100 110

Zeit nach Einbau / h

Time after installation / hrs

T

e

m

p

e

r

a

t

u

r

/

C

T

e

m

p

e

r

a

t

u

r

e

/

C

10 h / 500 C

min. 24 h Erhrtungsdauer

min. 24 hrs setting time

20 h / 110 - 150 C

15 C/h

25 C/h

30 C/h

bis zur Einsatztemperatur

up to temp. of application

Explosive spalling of castable surface (satellite cooler)

Dry out - surface cracking

Typical view on a badly

predried castable , cooler

sidewalls

Explosive spalling of Castable

Spalling of wet LCC castable on burner

Optimized drying schedule

Exhaust gas sealing of kiln and ducts

Protection against humid exhaust gases (filter, basic bricks)

Evaporation holes in the cycloneroof

lockable socket for controled evaporation

Heating up of kiln

Contraction at tyre

Limiting mechanical components

Temperaturedistribution in brick and kiln shell during heating up

In 8h to 1000C

Too slowly heating up, too early turning of kiln

Loose lining

migration, relativ

movement

Too fast heating up

Axial and radial pressure

Spalling , cobblestone surface

Done: Drying and heating successfully finished

first clinker in cooler

Typical timing:

78 h 120 h