CN102372489A - Production method of waterproof magnesite brick - Google Patents

Abstract

The invention relates to a production method of a waterproof magnesite brick for building permanent linings of an electric furnace and a revolving furnace in the field of ferrous metallurgy. The raw materials include 95-99.5 parts of magnesia containing more than or equal to 91% of MgO, 0.5-5 parts of boric acid and 3 parts of paper pulp; and a finished product is produced through the operation steps such as burdening, mixing, forming, drying, sintering, sorting and the like. The magnesite brick produced by using the method has high waterproof capacity, the problem of water leakage of a water cooled wall of the electric furnace and a water cooling tank at the opening of the revolving furnace at high temperature can be effectively solved, and the service life of the furnace lining can be greatly prolonged.

Description

A kind of method of manufacture of preventing hydration magnesia brick

Technical field

The present invention relates to the ferrous metallurgy field and build electric furnace and converter permanent liner working method by laying bricks or stones with the preventing hydration magnesia brick.

Background technology

Electric furnace and the converter safety liner overwhelming majority is with common magnesia brick (MgO >=91%) now; Because electric furnace water wall and converter saliva ice chest at high temperature move; Often leak inevitably; Make electric furnace and converter safety liner burn the magnesia brick aquation, and then cause part even big area furnace lining to come off, seriously shorten lining life.

Summary of the invention

The method of manufacture that the purpose of this invention is to provide a kind of preventing hydration magnesia brick; The magnesia brick that adopts this method to produce has very high preventing hydration ability; Can effectively solve the problem that electric furnace water wall and converter saliva ice chest at high temperature leak, the work-ing life that can improve furnace lining significantly.

For realizing above-mentioned purpose, the present invention realizes through following technical scheme:

A kind of method of manufacture of preventing hydration magnesia brick, the preventing hydration magnesia brick is processed by the following raw materials in parts by weight ratio:

Magnesia 95-99.5 part of MgO >=91%

Boric acid 0.5-5 part

3 parts of paper pulp

The grain size distribution of the magnesia of said MgO >=91% ratio by weight is:

The method of manufacture of said preventing hydration magnesia brick, step is following:

1) raw material pulverizing screening fine grinding; By described grain size distribution the magnesia of MgO >=91% is ground, sieves into desired particle size;

2) feed in raw material, mix; In said raw material weight ratio, add the magnesia particle of 3-5mm, 1-3mm granularity earlier, add the sand particle of 0.088-1mm granularity again, mixed 2-5 minute; Add paper pulp again, wet mixing 5 minutes; The magnesia powder of adding≤0.088mm and boric acid simultaneously then; Mixed 5-15 minute discharging again;

3) moulding; Pug after will mixing joins extrusion forming in the friction press mould;

4) drying; In temperature is dry in 100～140 ℃ the tunnel moisture eliminator, time 12-16 hour, requires moisture content in the base substrate≤0.5%;

5) burn till; Dried adobe delivered in the calcining kiln burn till 1600 ℃～1650 ℃ of firing temperatures, firing time 200-300 minute;

6) selection; To the finished product selection, permissible variation in dimension and outward appearance selection are according to the national standard of magnesia brick.

7) performance index; The performance index of preventing hydration magnesia brick require as follows: MgO>=91%; Compressive strength 55～75Mpa; 0.2MPa refractoriness under load T _0.6>=1550 ℃; Volume density>=2.83g/cm ³Apparent porosity 17～22%.

Compared with prior art, the invention has the beneficial effects as follows:

Compare with the existing magnesia brick of producing by national standard (MZ-1); Preventing hydration magnesia brick compressive strength than higher, volume density than higher, apparent porosity is lower; Especially more between its periclasite principal crystalline phase " liquid phase is glued " parcel; Reduce the chance that the periclasite principal crystalline phase contacts with water and steam, reduced material and water and steam response capacity significantly, increased substantially lining life.

Embodiment

Embodiment 1

A kind of method of manufacture of preventing hydration magnesia brick, the preventing hydration magnesia brick is processed by the following raw materials in parts by weight ratio:

97 parts in the magnesia of MgO >=91%

2 parts of boric acid

3 parts of paper pulp

The grain size distribution of the magnesia of said MgO >=91% ratio by weight is:

The method of manufacture step of said preventing hydration magnesia brick is following:

1) raw material pulverizing screening fine grinding; By described grain size distribution the magnesia of MgO >=91% is ground, sieves into desired particle size;

2) feed in raw material, mix; In said raw material weight ratio, add the magnesia particle of 3-5mm, 1-3mm granularity earlier, add the sand particle of 0.088-1mm granularity again, mixed 2-5 minute; Add paper pulp again, wet mixing 5 minutes; The magnesia powder of adding≤0.088mm and boric acid simultaneously then; Mixed 5-15 minute discharging again;

3) moulding; Pug after will mixing joins extrusion forming in the friction press mould;

4) drying; In temperature is dry in 100～140 ℃ the tunnel moisture eliminator, time 12-16 hour, requires moisture content in the base substrate≤0.5%;

5) burn till; Dried adobe delivered in the calcining kiln burn till 1600 ℃～1650 ℃ of firing temperatures, firing time 200-300 minute;

6) selection; To the finished product selection, permissible variation in dimension and outward appearance selection are according to the national standard of magnesia brick.

7) performance index; The performance index of preventing hydration magnesia brick require as follows: MgO>=91%; Compressive strength 55～75Mpa; 0.2MPa refractoriness under load T _0.6>=1550 ℃; Volume density>=2.83g/cm ³Apparent porosity 17～22%.

Embodiment 2

A kind of method of manufacture of preventing hydration magnesia brick, the preventing hydration magnesia brick is processed by the following raw materials in parts by weight ratio:

95 parts in the magnesia of MgO >=91%

5 parts of boric acid

3 parts of paper pulp

The grain size distribution of the magnesia of said MgO >=91% ratio by weight is:

The method of manufacture of said preventing hydration magnesia brick is with embodiment 1.

Embodiment 3

A kind of method of manufacture of preventing hydration magnesia brick, the preventing hydration magnesia brick is processed by the following raw materials in parts by weight ratio:

99.5 parts in the magnesia of MgO >=91%

5 parts of boric acid

3 parts of paper pulp

The grain size distribution of the magnesia of said MgO >=91% ratio by weight is:

The method of manufacture of said preventing hydration magnesia brick is with embodiment 1.

Claims (1)

1. the method for manufacture of a preventing hydration magnesia brick is characterized in that, is processed by the following raw materials in parts by weight ratio:

Magnesia 95-99.5 part of MgO >=91%

Boric acid 0.5-5 part

3 parts of paper pulp

The grain size distribution of the magnesia of said MgO >=91% ratio by weight is:

The method of manufacture of said preventing hydration magnesia brick, step is following:

1) raw material pulverizing screening fine grinding; By described grain size distribution the magnesia of MgO >=91% is ground, sieves into desired particle size;

2) feed in raw material, mix; In said raw material weight ratio, add the magnesia particle of 3-5mm, 1-3mm granularity earlier, add the sand particle of 0.088-1mm granularity again, mixed 2-5 minute; Add paper pulp again, wet mixing 5 minutes; The magnesia powder of adding≤0.088mm and boric acid simultaneously then; Mixed 5-15 minute discharging again;

3) moulding; Pug after will mixing joins extrusion forming in the friction press mould;

4) drying; In temperature is dry in 100～140 ℃ the tunnel moisture eliminator, time 12-16 hour, requires moisture content in the base substrate≤0.5%;

5) burn till; Dried adobe delivered in the calcining kiln burn till 1600 ℃～1650 ℃ of firing temperatures, firing time 200-300 minute;

6) selection; To the finished product selection, permissible variation in dimension and outward appearance selection are according to the national standard of magnesia brick.

7) performance index; The performance index of preventing hydration magnesia brick require as follows: MgO>=91%; Compressive strength 55～75Mpa; 0.2MPa refractoriness under load T _0.6>=1550 ℃; Volume density>=2.83g/cm ³Apparent porosity 17～22%.