CN111662730A - Composite lining plate for splicing coke tank and preparation method - Google Patents

Abstract

A composite lining plate for splicing coke tanks comprises a metal shell, an anchoring part and a casting material layer, wherein the metal shell at least comprises two sectors; the metal shell is provided with an anchoring piece, and the anchoring piece is connected with the metal net layer; coating a buffer layer; a heat insulation plate is arranged between the metal shell and the castable layer, and the anchoring piece is connected with the metal shell; the upper end and the lower end of each metal shell are respectively provided with a first connecting piece or a second connecting piece which are mutually matched and connected. The preparation method comprises the following steps: placing the metal shell into a mold; the anchoring piece is welded on the metal shell, and the upper end and the lower end of the outer wall of the metal shell are matched and connected with the first connecting piece or the second connecting piece; the metal mesh layer is fixed on the anchoring piece; coating a buffer layer; coating a refractory adhesive in the metal shell and paving an insulation board; pouring a casting material layer; standing and maintaining; baking; and (5) standby. On the premise of not increasing the manufacturing cost, the replacement cycle is prolonged from the original 6-12 months to the average service life of at least 12 months, and the maintenance cost can be reduced by at least 20%.

Description

Composite lining plate for splicing coke tank and preparation method

Technical Field

The invention relates to equipment for dry quenching in the coking industry, in particular to a structure of a refractory material composite coke tank lining plate.

Background

Compared with wet quenching, the dry quenching technology (CDQ) has obvious advantages, can recover the sensible heat of red coke, improve the coke strength, is beneficial to the iron-making operation of a blast furnace and reduces the coke ratio. The dry quenching device has long service life, and if the dry quenching production volume of an enterprise is not surplus, the production stop maintenance has great influence on the iron-making production, and the gap and guarantee problem of the iron-making dry quenching exists.

The coke tank is arranged on a coke tank carrying vehicle and is dragged by an electric locomotive to reciprocate under a coke oven hole and a dry quenching lifting derrick. The coke tank carries the red coke pushed out from the coking chamber, and the red coke is conveyed to the top of the dry quenching furnace and is matched with a loading device to load the red coke into the dry quenching furnace. Due to the continuous operation of the coke dry quenching system, the coke drum, which is in direct contact with the red coke, must have a high operational reliability. The temperature of the mature red hot coke pushed out from the coking chamber of the coke oven is about 1050 +/-50 ℃, the rotary coke tank drives a speed reducer by a driving motor to enable the coke tank to rotate around the center in the coke receiving process, and the speed reducer rotates 6-9 revolutions per minute, so that the loading coefficient of the coke can be improved, the weight and the volume of the coke tank can be reduced, and meanwhile, the particle size distribution of the coke in the coke tank can be improved. The rotary coke tank mainly comprises a coke tank body, a lining plate, a hanging rod, a transmission rod, an annular octagonal beam, a guide wheel set, a bottom gate, a buffer seat, refractory materials, a lubricating pipeline and the like. The coke tank body is mainly formed by welding a steel plate with the thickness of 10mm and T-shaped steel and is used as a support of the whole coke tank body, and the structural member is made of Q345B. The coke drum lining plate is used as a part which is in direct contact with red hot coke, and the material of the part needs stronger heat resistance and wear resistance, strength and toughness in a hot state and the performance of adapting to the alternating change of cold and heat. Some straight parts of the lining plate are made of heat-resistant iron castings, and the materials are QT 600-3, G35Cr24Ni7, ZG3Cr7Si2 or heat-resistant stainless steel 20X23H 18; the cone section and the bottom gate part lining plate are made of heat-resistant cast steel ZG35Cr24Ni7SiN, heat-resistant stainless steel 20X23H18 and the like, have good wear resistance and heat resistance, and can resist heat of 1100 ℃ in a short time. The lining plate of the coke tank of some companies is made of heat-resistant stainless steel, the connecting bolt in contact with the red coke is made of stainless steel with a large square head structure, and the connecting mode of the lining plate and the coke tank framework is firmer and more reliable; to improve the life of the lining plate and avoid premature damage.

The heat-resistant cast iron has good high-temperature resistance, is low in material price, but has high hardness, large brittleness, frangibility, incapability of finishing, poorer thermal fatigue performance and short service life, and is generally only used for a side wall lining plate. The medium chromium cast steel ZG3Cr7Si2 has good high temperature resistance, good chilling and heating resistance, better performance and moderate price, and has the defect of poor heat insulation performance compared with heat-resistant steel; the service life is short, and the cost is high. The heat-resistant alloy steel can resist the high temperature of 1130 ℃, but has high price, poor processability and difficult manufacture, and some domestic materials need to be imported.

As the coke tank and the coke tank cover of the dry quenching coke have short service life, the lining plate falls off, burns and damages and causes various equipment problems in the using process, thereby influencing the normal production of the dry quenching coke. 2520 cast steel pouring blocks are used for dry quenching rotary coke tank lining plates of a certain company, and the cast steel pouring blocks need to be integrally replaced once in 0.5-1 year on average. Due to the problems of materials and production operation, coke of a furnace end with a part of furnace number is generated to cause a coke tank of a cake coke, a lining plate is burnt for a long time, the local replacement of the lining plate of the coke tank is too frequent, and the maintenance cost is high; frequent replacement of the lining plates results in reduced dry quenching rate, reduced steam yield and reduced coke quality. If the damaged lining plate falls into the dry quenching furnace, the health of the maintainers can be seriously threatened in the treatment process. The bottom welt easily drops, causes the direct burnt cage structure that loses of red burnt, and life is shorter. Generally, a maintainer needs to stop the machine for overhauling the lower structure of the focusing cage frame once in 1-2 months, and is often forced to water to cool the coke tank due to the time and heavy task, and the quenching and suddenly heating of the lining plate and the structure of the focusing tank are greatly damaged. Frequent overhaul causes equipment materials, the cost of labor to be in the high consumption state all the time, and the structure warp after repairing repeatedly and is difficult to rectify seriously, leads to the welt installation difficulty, and vicious circle also can shorten the life of cage by a wide margin.

In the retrieved data, the dry quenching coke pot lining plate body described in Chinese patent CN108485684A is made of refractory castable by molding and baking; the liner plate keel is an n-shaped bracket made of phi 12mm stainless steel, and the n-shaped bracket is arranged in the length direction in the block body. The middle part of the top end of the n-shaped stainless steel bracket is welded with the head of a bolt, so that the screw is perpendicular to the plane of the bracket and extends out of the surface of the block body for a certain distance. The problem is that the diameter of a stainless steel keel in the refractory castable is too thick, the expansion coefficient is far larger than that of a refractory material, and the stainless steel keel is connected and fixed by one bolt only and is not firm, so that cracking is easily caused.

The thickness of the lower end of the lining plate at the root of the straight cylinder of the coke tank, which is described in the Chinese patent CN108531199A, is increased by 35mm compared with the original design value of the lining plate; the thickness of the lining plate of the coke discharge port of the lower cone body is reduced by 10mm compared with the original design value of the lining plate; wherein the material of the lining plate at the root of the straight cylinder of the coke tank changes the originally designed stainless steel material into a refractory castable. The problem is similar to CN 108485684A.

Chinese patent CN208980641U the compound welt of circular dry coke quenching coke jar include several coke jar bottom welts, conic section position welts, cylinder section position welts or go up the border welt, all set up several vertical and horizontal fin on the internal surface of every welt, make the internal surface form several recess, all set up the through-hole of being connected with the coke jar on every welt or/and set up the erection column of being connected with the coke jar at the welt back, the internal surface of welt all sets up the nanometer ceramic layer. The problem is that the nano ceramic layer is only arranged between the longitudinal and transverse convex ribs and grooves of different lining plates, the expansion coefficient difference between the ceramic layer and the steel structural member is large, and the ceramic layer is easy to expand, crack and fall off.

The dry quenching coke pot lining plate described in Chinese patent CN204265692U comprises a lining plate body, wherein the lining plate body is provided with a wire planting bolt hole and a connecting plate pin hole. The lining plate is characterized in that a 90-degree corner hook is arranged on the back of the lining plate body, an adjacent plate connecting through hole is formed in the 90-degree corner hook, and an adjacent plate connecting piece penetrates through the through hole. The purpose of which is merely to secure adjacent liner panels.

The coke pot lining plate described in Chinese patent CN203036233U comprises a lining plate body and a hook, and is characterized by also comprising a fastening device; can make the coke pot lining plate form a whole with the jar body better, the removal of the coke pot lining plate that has significantly reduced has also correspondingly reduced its expend with heat and contract with cold's deformation, has improved the life of coke pot lining plate.

The high-temperature wear resistant lining plate for the coke dry quenching tank, disclosed by the Chinese patent CN102212820A, is characterized by comprising a metal lining plate and a metal ceramic layer cladded on the surface of the metal lining plate, wherein the cladded metal ceramic layer is high-temperature resistant and wear resistant, and the problem is that the expansion coefficient of a metal piece and ceramic is difficult to match and is easy to crack and peel off due to too many hot and cold cycles of the coke tank.

The wear-resistant castable for coke pots, which is described in Chinese patent CN110668832A, comprises the following components: alumina with the diameter less than or equal to 5 mm: 30-68 parts of a solvent; alumina hollow spheres with the particle size less than or equal to 3 mm: 10-45 parts; alumina micropowder: 1-5 parts; silicon micropowder: 5-12 parts of a solvent; pure calcium aluminate cement: 3-10 parts; dispersing agent: 0.1-1 part; explosion-proof agent: 0.1-1 part; tartaric acid: 0.02-0.03 part. The wear-resistant castable for coke cans has good compressive strength, breaking strength and wear resistance, but has poor rapid cooling and heating performance and is easy to crack.

The castable for manufacturing the coke pot lining, which is described in Chinese patent CN109704792A, comprises the following components: high bauxite with a particle size in the range of 5mm to 8 mm: 10% -22%; calcium hexaluminate having a particle size in the range of 3mm to 5 mm: 20% -38%; calcined quartz with a particle size in the range of 1mm to 3 mm: 6 to 10 percent; forsterite having a particle size of 1mm or less: 11 to 21 percent; magnesium aluminate spinel with 180 mesh particle size: 9% -19%; ethyl silicate: 2% -7%; hydrated alumina with particle size less than 0.088 mm: 2% -10%; dextrin: 1% -4%; water reducing agent: 1 to 3 percent. The problem is similar to CN 110668832A.

The high thermal shock resistant wear resistant prefabricated part for the dry quenching coke tank, which is described in the Chinese patent CN110294623A, comprises: 20-30 parts of silicon carbide whiskers; 40-60 parts of bauxite-based homogeneous material; 5-10 parts of silicon dioxide micro powder; 1-3 parts of water; water reducing0.2-0.6 part of agent α -Al₂O₃15-20 parts of powder; MoSi₂8-12 parts of powder. The problems are that the alumina has poor thermal shock resistance, the silicon molybdenum powder is expensive, and the prefabricated member has poor effect.

The protection structure of the coke tank conical barrel section outlet, which is described in Chinese patent CN209669129U, comprises a conical barrel section positioned at the lower part of a coke tank, wherein the bottom of the conical barrel section is a conical barrel section outlet formed by pouring refractory materials, a circle of reinforcing rib plates are completely embedded in the refractory materials at the conical barrel section outlet, and the reinforcing rib plates are fixedly connected with the inner wall of the conical barrel section; the edge of the inner ring of the outlet of the conical cylinder section is also provided with a circle of stainless steel retaining ring, and the stainless steel retaining ring is connected with the reinforcing rib plate to form a protective groove wrapping the bottom of the outlet of the conical cylinder section. By designing the reinforcing rib plates, the reinforcing rib plates are matched with the poured refractory materials, so that the integral strength of the outlet of the conical cylinder section is enhanced, the conical cylinder section cannot collapse due to ablation, and the service life of the coke tank with the novel protective structure is prolonged; and meanwhile, the stainless steel protective ring is used for coating and protecting the refractory material, so that the problem that the refractory material falls into the dry quenching furnace due to abrasion or impact of coke is solved, and the usability of the dry quenching furnace is improved. The structure is that a circle of reinforcing rib plate is arranged in the refractory material of the outlet part, which has a reinforcing effect, but the expansion coefficient is different from that of the refractory material, so that the refractory material is easy to deform and crack at high temperature.

From a literature search: the coke pot mainly comprises heat-resistant cast iron and heat-resistant alloy, and the pouring lining of the refractory material is reported, but the composite lining plate is usually only reinforced by a stainless steel rib plate, so that the problem of lining plate material peeling caused by mismatched expansion coefficients exists. Therefore, it is necessary to develop a more practical coke tank composite lining plate to meet the production requirements.

Disclosure of Invention

Aiming at the defects of easy damage, falling, large heat transfer, complex castable construction, easy cracking and the like of the existing coke dry quenching tank lining plate in the prior art, the invention provides the composite lining plate for splicing the coke tank and the preparation method thereof, wherein the service life of the coke tank lining plate can be prolonged by changing the structure of the coke tank on the premise of not increasing the manufacturing cost, and the replacement period is prolonged to at least 12 months from one year, so that the maintenance cost can be reduced by at least 20%.

The measures for realizing the aim are as follows:

the utility model provides a compound welt for splicing coke drum, by the anchor assembly and the pouring bed of material of metal-back, metal-back inner wall and constitute, its lies in: the metal shell at least comprises two fans; on the anchoring piece of each metal shell, the anchoring piece is connected with the metal net layer; the anchoring piece and the metal net layer are coated with buffer layers; an insulation board is arranged between the metal shell and the casting material layer, and the anchoring piece penetrates through the insulation board and is connected with the metal shell; the upper end and the lower end of the outer surface of each metal shell are respectively provided with a first connecting piece or a second connecting piece; the first connecting piece and the second connecting piece are connected in a mutually matched mode.

It is characterized in that: the thickness of the metal shell is 5-10 mm, and the temperature resistance of the metal shell is not lower than 1000 ℃.

It is characterized in that: the diameter of the anchor is not more than 10 mm.

It is characterized in that: 55-70% of the materials in the castable are composed of microporous mullite aggregate or microporous andalusite aggregate with the granularity of 2-8 mm or the mixture of the microporous mullite aggregate and the microporous andalusite aggregate in any proportion, the volume density of the microporous mullite aggregate or the microporous andalusite aggregate is 2.60-3.2 g/cm3, and the apparent porosity is 3-8%.

It is characterized in that: the buffer layer is made of an organic material with a melting point not higher than 120 ℃; the thickness of the buffer layer does not exceed 1 mm.

It is characterized in that: the diameter of the metal wires of the metal mesh layer is not more than 5 mm; the side length of the meshes of the metal mesh layer is 10-20 mm.

It is characterized in that: the heat insulation plate is fixed through a fireproof adhesive.

It is characterized in that: the organic material is polyethylene or polypropylene plastic.

It is characterized in that: the refractory adhesive is aluminum dihydrogen phosphate solution.

The preparation method comprises the following steps:

1) after the mold is set, a metal shell is placed;

2) welding the anchoring piece on the inner wall of the metal shell; welding a first connecting piece or a second connecting piece which are mutually matched and connected on the outer surfaces of the upper end and the lower end of the outer wall of the metal shell;

3) fixing the metal mesh layer on the anchoring piece; 4) Coating a buffer layer on the metal mesh layer and the anchoring piece;

5) coating a refractory adhesive in the metal shell and paving an insulation board;

6) pouring a refractory castable layer;

7) standing and maintaining for 24-48 h;

8) baking at 100-120 ℃ for 24-36 h;

9) standby;

preparing the lining plates of the coke tanks of other fans according to the steps 1) to 8);

10) when the coke tank needs to be assembled, the connecting piece I or the connecting piece II at the upper end between the two adjacent composite coke tank lining plates of each fan are mutually matched and connected; similarly, the connecting piece I or the connecting piece II at the lower end between the two adjacent composite coke pot lining plates of each fan can be matched and connected with each other.

Effects of the essential Components of the invention

The metal mesh layer is connected to the anchoring piece, so that the casting material is radially supported and strengthened by the anchoring piece to prevent the anchoring piece from cracking and peeling, and the strength and the thermal damage resistance of the casting material can be strengthened by the metal mesh layer in the circumferential direction.

The buffer layers are coated on the anchoring piece and the metal net layer, because the expansion coefficient of the metal anchoring piece is large, and the expansion coefficient of the casting material is small, an expansion gap must be reserved so as to prevent the casting material from cracking caused by abnormal expansion in the temperature rise use process. The buffer layer does not absorb water in the molding process of the casting material, can be molded, is softened and melted to shrink in the temperature rising process, and is carbonized at high temperature to reserve an expansion joint, thereby being beneficial to digesting the expansion amount.

According to the invention, the refractory adhesive is coated in the metal shell and the heat-insulation board is laid, because the weight and the volume of the tank body limit, the pouring material layer cannot be too thick, so that the heat conduction is too large, the surface temperature of the metal shell is increased, the deformation is caused, and the heat loss is also caused; the nano-scale insulation board is adopted, only the insulation board with the thickness not greater than 8mm is needed, the surface temperature of the metal shell can be reduced, and the safety range is below 200 ℃.

Compared with the prior art, the service life of the coke pot lining plate can be prolonged by changing the structure and the materials of the coke pot lining plate on the premise of not increasing the manufacturing cost, the replacement period is prolonged from the original 6-12 months to the average service life of at least 12 months, and the maintenance cost can be reduced by at least 20%.

Drawings

FIG. 1 is a schematic view of a composite liner for splicing coke drums according to the present invention;

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1;

in the figure: the heat insulation structure comprises a metal shell 1, anchoring parts 2, a pouring material layer 3, a metal net layer 4, a buffer layer 5, a heat insulation plate 6, a connecting piece I7 and a connecting piece II 8.

Detailed Description

The invention is described in detail below with reference to the attached drawing figures:

a composite lining plate for splicing a coke tank comprises a metal shell 1, an anchoring part 2 connected with the inner wall of the metal shell 1 and a casting material layer 3, wherein the metal shell 1 at least comprises two sectors; a metal net layer 4 is connected or spot-welded with the anchoring piece 2 on the anchoring piece 2 of each metal shell 1, and a buffer layer 5 is coated on the anchoring piece 2 and the metal net layer 4; an insulation board 6 is fixed between the inner wall of the metal shell 1 and the castable layer 3 through a refractory adhesive, and the anchoring piece 2 penetrates through the insulation board 6 to be connected with the metal shell 1; the upper end and the lower end of the outer surface of each metal shell 1 are connected with a first connecting piece 7 or a second connecting piece 8 by welding or bolts; the first connecting piece 7 and the second connecting piece 8 are connected in a mutually matched mode.

The metal shell 1 is alloy steel, the thickness of the metal shell is 4mm/5mm/6mm, and the temperature resistance of the metal shell is not lower than 1005 ℃/1125 ℃/1150 ℃.

The diameter of the anchor 2 is 5mm/8mm/10 mm.

The castable layer 3 is formed by mixing heavy mullite or andalusite or the mixture of the heavy mullite and the andalusite with the granularity of 2-8 mm and containing micropores in any proportion, and the density of the heavy mullite or the andalusite is 2.60 cm³/2.85 cm³/3.20cm³The apparent porosity was 3%/5%/8%.

The melting point of the buffer layer 5 is 116 ℃/88 ℃/105 ℃/organic material, or polyethylene or polypropylene; the thickness of the buffer layer was 0.83mm/0.92mm/1 mm.

The diameter of the metal wire of the metal mesh layer 4 is 3mm/4.2mm/5 mm; the side length of the grid of the metal net layer 4 can be within any value of 8-20 mm.

The preparation method comprises the following steps:

1) after the mould is set, a metal shell 1 is put in;

2) welding the anchoring piece 2 on the inner wall of the metal shell 1; welding a first connecting piece 7 or a second connecting piece 8 which are mutually matched and connected on the outer surfaces of the upper end and the lower end of the outer wall of the metal shell 1;

3) coating a fireproof adhesive on the inner wall 1 of the metal shell, laying and fixing a heat insulation plate 6;

4) fixing the metal mesh layer on the anchoring piece;

5) coating a buffer layer 5 on the metal mesh layer and the anchoring piece;

6) pouring a refractory castable layer 3;

7) standing and maintaining for 24-48 h;

8) baking at 100 ℃/112 ℃/120 ℃ for 29.5h/36h/24 h;

9) standby;

preparing the lining plates of the coke tanks of other fans according to the steps 1) to 8);

10) when the coke tank is assembled, the connecting piece I7 or the connecting piece II 8 at the upper end between the two adjacent composite coke tank lining plates of each fan are mutually matched and connected.

Through test tests, the three coke cans spliced by the composite lining plate respectively tried at present are tried for 10 months, 13 months and 16 months correspondingly, the coke cans of 10 months and 13 months are tried, the phenomena of damage, shedding and cracking are not found, and the coke cans can be tried for at least 3.5 months according to the conditions; the coke pot which is tried for 16 months has the phenomenon of local small amount of damage and shedding, and can still be continuously applied for 1-3 months after being repaired according to the condition.

The specific embodiments are merely preferred examples and are not intended to limit the embodiments of the present invention.

Claims (10)

1. The utility model provides a compound welt for splicing coke pot, comprises the anchor assembly and the pouring bed of material of metal-back, metal-back inner wall, its characterized in that: the metal shell at least comprises two fans; on the anchoring piece of each metal shell, the anchoring piece is connected with the metal net layer; the anchoring piece and the metal net layer are coated with buffer layers; an insulation board is arranged between the metal shell and the casting material layer, and the anchoring piece penetrates through the insulation board and is connected with the metal shell; the upper end and the lower end of the outer surface of each metal shell are respectively provided with a first connecting piece or a second connecting piece; the first connecting piece and the second connecting piece are connected in a mutually matched mode.

2. The composite liner for splicing coke drums of claim 1, wherein: the thickness of the metal shell is 5-10 mm, and the temperature resistance of the metal shell is not lower than 1000 ℃.

3. The composite liner for splicing coke drums of claim 1, wherein: the diameter of the anchor is not more than 10 mm.

4. The composite liner for splicing coke drums of claim 1, wherein: 55-70% of the materials in the castable are formed by microporous mullite aggregate or microporous andalusite aggregate with the granularity of 2-8 mm or by mixing the microporous mullite aggregate or the microporous andalusite aggregate with the granularity of 2.60-3.2 g/cm in volume density or by mixing the microporous mullite aggregate or the microporous andalusite aggregate with the microporous andalusite aggregate in any proportion³The apparent porosity is 3 to 8%.

5. The composite liner for splicing coke drums of claim 1, wherein: the buffer layer is made of an organic material with a melting point not higher than 120 ℃; the thickness of the buffer layer does not exceed 1 mm.

6. The split-joint composite coke drum liner of claim 1, wherein: the diameter of the metal wires of the metal mesh layer is not more than 5 mm; the side length of the meshes of the metal mesh layer is 10-20 mm.

7. The composite liner for splicing coke drums of claim 1, wherein: the heat insulation plate is fixed through a fireproof adhesive.

8. The composite liner for splicing coke drums of claim 5, wherein: the organic material is polyethylene or polypropylene plastic.

9. The composite liner for splicing coke drums of claim 7, wherein: the refractory adhesive is aluminum dihydrogen phosphate solution.

10. The method of making a composite liner for splicing coke drums of claim 1, wherein:

1) after the mold is set, a metal shell is placed;

2) welding the anchoring piece on the inner wall of the metal shell; welding a first connecting piece or a second connecting piece which are mutually matched and connected on the outer surfaces of the upper end and the lower end of the outer wall of the metal shell;

3) fixing the metal mesh layer on the anchoring piece;

4) coating a buffer layer on the metal mesh layer and the anchoring piece;

5) coating a refractory adhesive on the inner wall of the metal shell and paving an insulation board;

6) pouring a refractory castable layer;

7) standing and maintaining for 24-48 h;

8) baking at 100-120 ℃ for 24-36 h;

9) standby;

preparing the lining plates of the coke tanks of other fans according to the steps 1) to 8);

10) when the coke tank needs to be assembled, the connecting piece I or the connecting piece II at the upper end between the two adjacent composite coke tank lining plates of each fan are mutually matched and connected; similarly, the connecting piece I or the connecting piece II at the lower end between the two adjacent composite coke pot lining plates of each fan can be matched and connected with each other.

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