DE2719587A1 - RAW MIXTURE FOR THE PRODUCTION OF REFRACTORY CLAY DECENT - Google Patents

Description

A ' i

PATENT LAWYERS CELLENT

ZWEIBRÜCKENSTR. 15th 8OOO MUNICH 22

Tashkentsky J Kautschno-Issledowatelski j i Frojektnyj Institute

p AQ 4o

Stroitelnych Mate ^ ialow
"KII3TR0M -PROJECT" ² * ^Kai

ROHMISCSUIi G TO GENERATE FEUSHFiSIEU T CIvZHIS " CEMENT

The present invention relates to the cement industry, in particular a roll neck for the production of refractory alumina decent designed for use in the Refractories technology is bestiznat.

Raw mixtures for the production of refractory are known Alumina cement, technical alumina, barium or Contain strontium carbonates or sulfates (A. 3ranisky, Silikattechnik No. 1, 1961, pp. 17 to 85).

Use cement to produce the refractory alumina the above-mentioned raw mixtures are fired at temperatures of 1500 to 160 ° C., which requires a considerable amount of energy and the need to use refractory lined kilns.

Also known is a raw mixture for producing ^a refractory alumina-containing barium-zirconium cement, the earium carbonate as the main component and technical alumina

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and contains zirconia as an acidic component (SU Copyright Certificate No. 3 ^ 5 773).

The cement produced from the above-mentioned raw mixture is characterized by a high and extremely high level of fire resistance (Ms 2500 ⁰ C). To produce the zenens mentioned, however, the raw mixture is "fired at a temperature of 1600 to 16 ° C ⁰ C, which is associated with a considerable expenditure of energy and the need to use specially refractory-fed kilns.

It is the purpose of the present invention to eliminate the disadvantages mentioned.

The invention is based on the problem of the energy expenditure and the firing temperature in the production of refractory alumina cement by intensifying the formation of clinker by introducing catalytic additives into the corresponding raw mixture.

This problem was solved in that the

one

Raw mix for making / refractory clay.

earth cementSi the barium or strontium carbonate as the main

a

constituent and clay or / Toneide-zirconium dioxide mixture contains as an acidic component, also according to the invention Chloride of at least one of the metals barium, strontium, sodium, potassium with the following ratios between has the mentioned ingredients in lass percentage:

E & rium or strontium carbonate 40 to 62

Chlorides of the metals mentioned 5 to 20

Alumina or alumina-zirconium dioxide mixture in a ratio of 1:14 to 5 * 1 remainder to 100. 70984 7/0802

The inventive Rohmischurig the solubility is necessary to reduce the ijiergieaufwand in Zenenterzeugung un 30 to 35% and the firing temperature to 3CO to 50O ⁰ C.

one

For the production / alumina-containing strontium zirconium cement of the highest fire resistance (2250 to 2500 ⁰ C), a raw mixture is recommended, which consists of the following components in percentage:

Strontium carbonate 40 to 56

Zirconia 36 to 29

Alumina 4 to 10

Chlorides of the metals mentioned 5 to 20

Tsar Egg? 7, '.? U (/ un £; / 2 & riuir.-aluminous cement from 1? 20 to

1830 ⁰ C fire resistance, a raw mixture is recommended, which consists of the following components in percent by mass: barium carbonate 50 to 60

Alumina 30 to 35

Chlorides of the metals mentioned 20 bis

one

For the purpose of producing / alumina-containing bariur-zirconium

with a <^ ~>

cement <from 1850 to 2300 ° ^ fire resistance becomes a Soem mixture recommended, which consists of the following ingredients in oily percentage consists of:

Barium carbonate 50 to

Zirconia 5 bis

Alumina 25 to

Chlorides of the metals mentioned 20 bis

one

For the purpose of producing / alumina-containing Bariux-Zirkoniux-

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For cement with the highest level of fire resistance (25CC to 25CO ⁰ C), a raw mixture is recommended that consists of the following components in percent by weight;

Barium carbonate AO to 62

Zirconia 37.3 to 22

Alumina 2.7 to 11

Chlorides of the aforementioned metals 20 to 5. The process for producing the raw mixture according to the invention is carried out as follows.

The starting ingredients are ground together or separately and then mixed.

The L'Ahlen and Voi ^ miuchung recovered in the ea ι speaking amounts of raw materials components is carried out either in a dry process, in which all the ingredients in dried egg iorrn together or separately in a. Grinding unit are introduced, or in the Hafe method with the addition of 25 to 35

one
Mass percent V "ater and / or aqueous solution of the ⁿ used

Chlorides for raw sludge processing, for the generation of grades

one

nalien are 6 to 9 percent by mass of water or / aqueous solution of chlorides introduced into the dry mixture.

The above-mentioned proportions of the components in dei Mixture are based on the content of -Barium- and Strontium monoaluminates and / or monozirconates that contain the Determine the properties of the cements, selected.

The length of the chlorides depends on the required Relationship between the above-mentioned minerals in the end product and the burning technology of the Eohmischunc.

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2 B. in the case of firing temperatures of 1000 to 11CO ⁰ C a larger number of chlorides (15 to 20 percent lilacs) and in the case of firing temperatures of 1200 to 1 CO ⁰ C 5 to 10 percent by mass of chlorides.

Las presence of chlorides in the raw mixture =; contributes to the development of the reaction medium:

the liquid phase already at a temperature of 900 to

presence

1COO ⁰ C at. I ⁿ / of the aforementioned acticnsmediuris, the /

from 'molten salts of barium, strontium, potassium and l.atriune chlorides exists, the Dekarbonisac ions before ^ LLn ever of barium and strontium carbonates η significantly intensified * the dissolution of oxides of the raw material star * a: rush and the Crystallization processes of the above-mentioned Zenent ^ ineralisi accelerated »

A spiked and homogenized dry raw mixture or granules or sludge are given to a V. ^! 'supplied är2iexaschir.ensat where the Katerial is fired at temperatures from 1000 to 1300 ⁰ C.

The clinker produced can be a predetermined amount of Contains residual chlorides. After the Brerjaen the clinker will be cooled and until the required 'ioilchendispersitat to cement grinding

One advantage of the present invention is the

Intensification of clinker formation with simultaneous production

the

Reduction of the energy expenditure among others $ 0 to 35 / <> and / or lowering of the firing temperature to 10C0 to 1300 ⁰ C with a corresponding reduction of the specific consumption ar. Fuel or electrical energy.

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Lie present invention allows the quality of the

Sncoroduktes to sell due to the increase in its purity and

better / He fire resistance and activity to increase.

rj.e raw mixture containing chloride enables the Exzeueines

gung / refractory alumina cement s in traditional · lined furnaces ^and reduces the existing constraints in terms of the
/ Purity of the raw materials used.

For a better understanding of the present invention concrete examples are given below.

Example 1.

A raw mixture for the production / alumina-containing

prepared strontium-zirconium cement with the following composition in oleo percent:

Strontium carbonate 40

Zirkoniundioacid 3 €>

Clay 4

Barium chloride 20.

The technical alumina is ground in the wet process to a residue on a sieve with 63 / na meshes of not more than 10 percent by weight. To grind the clay, 30 percent by weight Viasser is added. In the alumina sludge formed, arium chloride is introduced in a ratio of 1: 5 to the mass of the alumina with the addition of Viasser up to a total moisture content of the barium-alumina sludge of $ 0% . The above-mentioned sludge is treated with a stream prepared by the Gemein & sL e Haßverxahlung of strontium carbonate and zirconium dioxide with 32: s per cent water.

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tium zirconium dioxide with 22 liases per cent of the water Strontiuzi-ZirkoniuEKhlamni mixed.

The raw mixture produced is pre-dried in the air.

from
net and in Forz: \ 5 to 10 mn large particles granulated.

The granules are at a temperature of ICOO to 1100 ⁰ C until complete 3eenii ~ irr the kerbildung, which is due to the lack of unbound iirO and

BaO is tested, fired.

the

The clinker formed is characterized by / presence from 50 to 55 cash percent Strontiur ^ ionozirkcnat, up to 25 urea percent barium monoconate and 15 to 20 l'.acsc percent Strontium and barium moncaluxinate.

The clinker is up to a Küclc ^ tand'auf oir.'jrc ^ xc. with 80 / «ia v; side pockets (you can check 10 percent.

The generated zone is characterized by the following properties marked:

Compressive strength, kp / cn

after 72 hours 245

after 168 hours 280

after 672 hours

Fire resistant ksit 2290 ⁰ C.

Example 2.

one

It is a raw mixture for production / alumina Strontiun zirconia incentives with the following composition processed in left percent:

Strontium carbonate 56

Zirconia 29

Clay 10

Strontium chloride 709847/0802 5.

AO

The technical alumina is up to a ^ residue au .. 'a sieve nit 10 m wide and vexation of not marry percent over 6 Hasse. Strontium chloride, zirconium dioxide, and strontium chloride are similarly ground. The ground components are vemischt and homogenized · Las erzeug te Hohnehl fired in limbo for a! Temperature from 1100 to 1200 ^0C. The hlinier formed is cooled and ground up to a residue on a sieve, via wide pockets of 7 percent by weight.

In the cement produced there is 65 to 70 percent strontium mono-zirconate and 30 to 55 percent by weight trorium monoaluminate, free SrO is absent.

The zenent generated is characterized by the following properties marked:

Compressive Strength, kp / cm

after 72 hours 290 after 168 hours 325 after 672 stands 410 Fire resistance 2240 ⁰ C. Example 3.

one

A raw mixture for the production / alumina

hajtigen strontium-zirconium cement with the following composition prepared in percent by mass:

Strontium carbonate 48

Zirconia 35

Clay 7

Barium chloride 8

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Strontius chloride 4

The components mentioned become ^ in Rohschlara formed in analogy to Example 1.

The granules are at a temperature of 12C0 to 13CO ⁰ C until the complete end of the

Burned clinker formation

the

The clinker formed is characterized by / before r ^ ndei- be from 70 to 75 liass% Strontiun ^ onozirl-cc.iat, up to 50% strontiucconoalucinate and 5% 7% barium nonaluminate

<f>

The clinker is down to one residue;

Sieve with 80 from wide meshes ^ on 10 mass percent = digging.

The cement produced has the following properties marked:

Compressive Strength, kp / cm

after 72 hours 260

after 168 hours 305

after 672 hours 325

Fire resistance 2430 ⁰ C.

Example 4.

one

A raw mixture for the production / alumina-containing strontium-zirconium cement is prepared with the following composition in percent by mass:

Strontium carbonate 40

Zirconia 36

Clay 4

Strontium chloride 10

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Potassium Chloride "8

Sodium chloride 2

A raw slurry is made from the ingredients mentioned formed in analogy to Example 1.

The granules v / earth at a temperature of 1200 to 130O ⁰ C up to the complete 3eendig \ inc der

Burned clinker formation.

the

The clinker formed is characterized by / presence from 65 to 70 percent Strontium zirconate and up to 35 percent strontium monoalumir.a- from

The clinker is ground to a residue on a sieve with 80 * _A m wide meshes ^ ron 1C permeable ^. The cement produced is procured by the following

marked:

Compressive Strength, kp / cm

after 72 hours 23Ο

after 168 hours 265

after 672 hours 315

Fire resistance 250O ⁰ C.

Example 5 »

one

It becomes a raw mix for production / alumina-containing strontium-zirconium cement with the following composition prepared in percent by mass:

Strontium carbonate 44

Zirconia; 32

Corundum (converted to alumina) '9

Barium chloride 3

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Strontium chloride 9

Potassium chloride 2

Sodium chloride 1

The corundum powder with a milk dispersity of under 90 / rna, ait is used in the above-mentioned components Mixes analogously to Example 2.

The Sohmehl produced is burned in floating state at a temperature of II50 to 1250 ⁰ C until complete termination of the clinker formation. The clinker marks

the
by / presence of 65 to 70 percent brron-

and
tium monozirconate / 30 to 35 percent by mass Strontiuc-ncno-

aluminate.

O The clinker becomes a bi3. Residue on one

80 mVO sieve. wide ashes <10 per cent / vs grind.

The cement produced is characterized by the following properties

marked:

2
Compressive Strength, kp / cm

after 72 hours 275

after 168 hours 320

after 672 hours 360

Fire resistance 24A-O ⁰ C

Example 6,

one

It becomes a raw mixture for production / containing toner Strontium zirconium cement with the following composition prepared in percent by mass:

7 Ci 9847/0802

Strontium carbonate 4-1

Zirconia 31

Clay 3

Potash dichloride 20

The raw meal is prepared in analogy to Example 2. The raw meal produced is burned in a suspended state at a temperature of 1150 to 12CO ⁰ G until the clinker formation is complete. The clinker is noticeable

the

by / presence of 70 to 75 ^ asseiDrozent Ssrcntium- and

monozirconate / 25 to 30 percent by mass of strontiumonc ^ luniinate

The clinker is up to a backward anal on a ^ ii \

with 80 ^ m wide tabs / of 10 cash percent). Zecent produced is by the following Sigenschafcer. marked:

Compressive Strength, kp / cm.

after 72 hours 253

after 168 hours 310

after 672 hours 33Ο

Fire resistance e.g. 10 ° C.

3 example 7 »

of a raw mixture for the production / alumina

containing strontium zirconium cement with the following composition prepared in I £ ate percent:

Strontium carbonate ^ -1

Zirconia 29

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Clay 10

Potassium chloride 5

Sodium chloride 15

The raw meal is prepared in analogy to Example 2. The Hohmehl produced is burned in suspension at a temperature from 1200 to 1250 ⁰ C until full completion of the clinker formation · The clinker is characterized

the
due to the presence of 60 to 65 percent strength by mass

and
tium monozirconate / 35 to 40 percent by weight Strcnsiuczor-oalu-

minat. .

The clinker is bi3 to a residue - on a she ": with 80 aahl broad lashes / of 10 lass% / veneer. The cement produced is characterized by the following properties:

Compressive Strength, kp / cm

after 72 hours 265 after 168 hours 310 after 672 hours 335 Fire resistance 2300 ⁰ C. Example 8,

A high mixture is used to produce g / barium

High alumina cement with the following composition in mass percent processed:

Barium carbonate 50

Clay 30

Barium chloride dihydrate (converted to ararium chloride) 20

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The technical clay is ix wet process "up to one Residue on a sieve nit 6J * a v.eiten pockets \ yon not more than 10 percent). For choices of clay 30 percent by mass of 7 water is added. In the educated Alumina is in a ratio of barium achloride dihydrate 2: 3 to the balance of the alumina based on BaCl- introduced. The Schiana mentioned is connected with one by the aüver :: ^ hlur.c; prepared Ecjrivojschlanm mixed.

The raw mixture produced is pre-dried in the air

from
and granulated in particles from 5 to 10 mm in size.

The granules are burned at a temperature of 1050 to 115O ⁰ C until the clinker formation is complete, which is checked by the absence of unbound BaO.

The clinker formed is cooled. The clinker ^is /

Barium monoaluminate The clinker is left to a residue 'on a sieve with 63 * / ΐη wide i »iaschen <ycn 10 percent / nahlen.

The cement produced is characterized by the following properties

marked:

Compressive Strength, kp / cm

after 24 hours 310

after 72 hours 39Ο

after 168 hours 490

after 672 hours 510

Fire resistance 1330 ⁰ G.

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Example 9

one

Ls v; ird a raw mixture for the production / Bariun alumina scents with the following composition ir. Lla-sc percent processed!

Barium carbonate 58

Clay 32

Earium chloride 8

Potassium chloride 1

Iv & trium chloride 1

The mixture is prepared for Example 8 by means of a grinding mill. The granules produced are tested at a temperature from 1100 to 1200 ⁰ C until the complete cessation of clinker formation, as lel'len unbound BaO, burned. I replied

the end
Clinker made of barium monoaluminate is cooled down.

and then up to a residue / on a sieve cit 63, ^ a wide meshes of 10 percent by mass / niching.

The cement produced has the following properties, marked:

Compressive Strength, kp / cm

after 24 hours 29p

after 72 hours 355

after 163 hours 460

after 672 hours 49O

Fire resistance 1820 ° C.

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BATH ORIGINAL Example 10.

one

A raw mixture is used to produce / Bariu ^ -

Clay decents with the following addition in ... '. Uss cent processed:

Barium carbonate 60

Clay 35

Barium chloride 4

Sodium chloride 1

The mixture is prepared by the procedure of Example Naßvermahl ^s. 1

The granules produced are at a · 'temperature 1200-1250 ⁰ C until the complete cessation of integrated clinker formation, which is checked by the absence of unbound BaO, burned.

the end

The clinker produced, the / Bariummonoaluninat is, it is cooled and "to a residue on a Siebymit 63 μ m wide stitches on ^ 10 ^ Hassepro; ■ -;:; '- ^ milled.

The cement produced is characterized by the following properties marked:

Compressive Strength, kp / cm

after 24 hours 305

after 72 hours 335

after 168 stands 460

after 6-2 hours 485

Fire resistance 1830

70984 7/0802

C.

Example 11.

one

It "becomes a raw mixture for spontaneous production / Bariun alumina cement with the following composition in lass percent processed:

Barium carbonate 53

Clay 3 ^ ·

• Strontius chloride 10

Potassium chloride 3

The mixture is then ground in analogy Example 8 prepared.

The granules produced are of clinker formation, which is checked by the absence of unbound 2AO at a Te nperasur 1100-1200 ⁰ C until complete i "bschlu5 fired.

the end

The clinker produced, which in the v / e sent borrowed / B

aluminate with a strontium monoaluminate content of 10 until 15 hatred percent is there, it is cooled down and on to a residue 'on a sieve with 63 z * si Meshes of 10 percent by weight).

The cement produced is characterized by the following properties:

Compressive Strength, kp / cm

after 24 hours 310 after 72 hours 390 after 168 hours 445 after 672 hours 470 Fire resistance 176C ⁰ C. 709847/0802

8.0

Example 12 «

of one It becomes a mockery of the generation / tonerio-

containing barium-zirconium cement with the following additions preparation in percent by mass:

Barium carbonate 50

Zirconia 5

Clay 25

Barium chloride 20

The mixture is prepared in analogy to Example 1 by wet grinding.

The granules produced are at a temperature of 1000 to 1100 ⁰ C until the clinker formation is complete, which is due to the lack of unbound. BaO is tested, fired. Dev clinker produced "consists of ice 80 mass percent Bariummonoaluminat and 15 to 20 percent by mass ^ ariummonozirkonat The clinker is to a residue / on a sieve of 63 t., M wide stitches

Γ / on a sieve with 62 /, 10 percent by weight / ground.

The cement produced is characterized by the following properties marked:

Compressive Strength, kp / cm

after 72 hours 59O

after 168 hours 830

after 672 hours 890

Fire resistance 1890 ⁰ C.

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Example 13 «

of a video mixture for spontaneous generation / alumina

containing Bariun zirconia cement with the following composition prepared in I ^ ate percent:

Barium carbonate 62

Zirconia 22

Clay 11

Strontium chloride 5

The mixture is made by Naßfrermahjen in analogy to Example 1 prepared.

The granules produced are fired at a Itaperatür 1200-1250 ⁰ C to initially full completion of the clinker formation, which is checked by unbound 3AO and SrO at Rehlen. The clinker produced consists of 30 to 35 percent barium monozirconate and up to 70 percent barium monozirconate. The Klinl-ctr v. Is ground up to a residue on a sieve with 63> av / iron meshes of 10% by weight. The cement produced is characterized by the following properties:

Compressive strength, kp / cm ²

after 2 hours 410 after 168 hours 490 after 672 hours 560 Fire resistance 2280 ⁰ C. Example 14.

There is a high mix for the production / tcnerde-

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containing Bariun-Zirkoniurizenients with the following composition prepared in percent by mass:

Barium carbonate 56

Zirconia 14

Clay 17

Barium chloride 10

Potassium chloride 2

sodium chloride 1

The mixture is prepared by means of cash milling in ^ nalo ^ ie for example 1 and burned at a temperature of 1100 "to 1200 ⁰ C until the clinker formation is complete, which is checked for the absence of unbound EaO. The clinker produced consists of ρ 5 up to 40 percent by mass of barium monocircnate and 60 to 65 percent by mass of ariuamonoaluminate

O /

Grind residue on a sieve with 63 ^ n wide flaps \ by mass percent /. The cement produced is characterized by the following properties:
Compressive Strength, kp / cia

after 72 hours 450 after 168 hours 610 after 672 hours 720 Fire resistance 2050 ⁰ C. Example 15.

_ one

ms is a mixture for the generation / alumina

prepared barium-zirconium cement with the following additive in percent by mass:

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Barium carbonate 40 Zirconia 37.3 Clay 2.7 Barium chloride 15th Potassium chloride 5

The mixture is prepared in analogy to Example 2.

The raw meal produced is burned in a suspended state at a temperature of 1150 to 125O ⁰ C. The clinker produced contains 5 to 7 percent barium monozirconate, the rest - barium monozirconate.

The clinker is deposited on a sieve with 63 / jo. wide liaschenvron IO let percent ^ wed.

The cement produced has the following properties:

Compressive Strength, kp / cm

after 72 hours 155 after 168 hours 270 after 672 hours 340 Fire resistance 2500 ⁰ C. Example 16.

A raw mixture for the production / tcnerde-

containing barium-zirconium cement with the following composition prepared in percent by mass:

Barium carbonate 62

Zirconia 22

Clay 11

709847/0 802

Barium chloride

The mixture is aufbereite in analogy to Example 2 The Hohmehl produced is burned in suspension at a temperature of 1250 to 130o C ^0. The clinker produced consists of 60 to 65 mass percent - ^ ariuiorionozirkonat and up to 40 mass percent barium monoaluminate.

The clinker is ground to a residue / on a sieve with 63 µm wide casings of 10 percent percent. The cement produced has the following properties: compressive strength, kp / cm

after 72 hours after 168 hours

after 672 hours fire resistance 239O ⁰ C.

Example 17.

A mixture is used to generate it / alumina

containing barium-zirconium cement with the following composition prepared in percent by mass:

Barium carbonate 50

Zirconia 30

Clay 7

Barium chloride 8

Strontium chloride 2

Potassium chloride 2

sodium chloride 1

The mixture is prepared in analogy to Example 2

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The raw shark produced is in suspension at a temperature of. · Baked 1200 to 1250 ⁰ C. The blinker formed consists of 70 to 75 percent by mass Sariucncnozirkonat and 25 to 30 percent by mass Bariucnonoaluninat.

The clinker is nailed down to a residue / on a sieve with 63 .mu.m wide pockets of 10%. The zenent produced has the following properties: compressive strength, kp / cm

after 72 hours 320 after 168 hours 44-5 after 672 hours 500 fire resistance 2410 ⁰ C,

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Claims (5)

PATENT Attorneys ^ P 69 ZELLENTiN - 2 ¹ S ZWEIBRÜCKENSTR. 15th 8OOO MUNICH 22 "7 719 FILE ACTION . 1. High mixing for .production of refractory m lOr.erds- cement, the barium or carbonate carbonate as the main a
constituent and alumina or / l'on earth-zirconium-oxide ge-isch having as an acidic component, characterized that they also contain chloride of nin- ens
at least one of the metals barium, Strontina, Ilatriun, Potassium with the following ratios between the; Ingredients in percent by mass: I. Barium or strontium carbonate 40 to 62 chlorides of the metals mentioned up to 20 alumina or alumina-zirconium dioxide mixture in a ratio of 1:14 to 5: 1, each remainder up to ICO. 2. hat according to claim 1, characterized in that, mark t that they consist of the following. Duration- , divide in l'.asse percent consists of: Strontium carbonate 4-0 to 56 ZirkorJ-uc-dioxide 36 to 29 Alumina 4 to 10 chloride of at least one of the metals - barium, strontium, sodium, Potassium - 20 to 5. 3. hollow mix according to claim 1, characterized marked that they are from folger.cc-n 2e- 709847/0802 ORIGINAL INSPECTEÖ standard parts in lass epr ο ζ ent consists: Barium carbonate 50 to 60 (Alumina 30 to 35 Chloride of at least one of the metals - barium, strontium, Sodium, potassium - 20 to 5. 4-, unmixed according to claim. 1, thereby characterized in that they a \ js the following Be süändieilen in üass% consists of: Barium carbonate 50 to 62 Zirconia 5 to 22 I'onerde 25 to 11 Chlorides of at least one of the metals - barium, strontium, Sodium, potassium - 20 to 5 5. Mixture according to claim 1, characterized marked that it consists of the following components in slaughter percent: Barium carbonate 40 to 62 Zirconia 37.3 bis Clay 2.7 to Chlorides of at least one of the lethal - barium, strontium, sodium, potassium - 20 to 5 _# 709847/0802