CN101434490A - Composite fire resistant pouring material - Google Patents

Abstract

The invention relates to an organic-inorganic composite combined advanced monolithic refractory which has the formula of 40 to 56 percent of 5-1mm corundum or bauxite, 12 to 30 percent of 1-0.0088mm corundum or bauxite, 16 to 25 percent of corundum or bauxite with d90 less than 0.088mm, 0 to 5 percent of alpha alumina micropowder, 1 to 8 percent of hydratable alumina, 1 to 6 percent of siliceous dust, 0 to 2 percent of calcium aluminate cement, 0.05 to 0.4 percent of external efficient water reducing agents (polycarboxylic acid plus sulfonation naphthaldehyde polymer plus sulfonation melamine polymer), 1 to 6 percent of latex of the system of external polyacrylic acid, 1 to 6 percent of external water and 0 to 3 percent of external heat-resistant steel fiber. Casting materials of the invention have excellent performances of condensation, hardening, demoulding, drying and heating and are suitable for high-temperature furnace projects with changeful field conditions.

Description

A kind of composite fire resistant pouring material

Technical field

The present invention relates to the senior unshape refractory of the compound bonded of a kind of organic-inorganic.Under the normal temperature, but mainly rely on the reaction of inorganicss such as polyacrylic acid emulsion and ALUMINA HYDRATE to form polyacrylic acid aluminium (calcium), form three-dimensional crosslinking structure fast and controllably, thereby obtain good to condense, sclerosis, the demoulding and drying property.Under the high temperature, mainly rely on the reaction of silicon ash and aluminum oxide to form mullite and form stable pottery combination, thereby obtain the good temperature resistance energy through sintering.

Background technology

Unshape refractory is widely used.Wherein, low cement, ultra-low cement refractory castable are main unsetting descriptions of materials.Press the regulation of ASTM: CaO content=2.5 ~ 1.0% of low cement deposit material; CaO content=1.0 ~ 0.2% of ultra-low cement deposit material; CaO content≤0.2% of non-cement mould material.

Generally, mould material needs admixture cement to condense, harden with acceleration, improves demoulding strength and strengthens sintering.But cement contains more objectionable impurities CaO.Under the high temperature, CaO can increase the quantity of liquid phase, the performance of infringement material.Very high in temperature, perhaps corrode fierce occasion, CaO will have a strong impact on the result of use of material.In other words, if cement consumption is many, with the high-temperature behavior of infringement material; But cement consumption has lacked, and can not satisfy the workability of material again.For example, the low-cement refractory pouring material forming property is good, but high-temperature behavior is relatively poor.The ultra-low cement deposit material forming property is relatively poor, and high thermal resistance but increases; Non-cement mould material forming property is very poor, but through obtaining excellent high-temperature behavior behind the abundant sintering.

For avoiding introducing CaO, studied MgO-SiO ₂-H ₂O is in conjunction with system.Under the normal temperature, this system relies on the aquation of MgO, and Mg (OH) ₂Produce the cohesion combination with the effect of silicon gray surface, thereby obtain required shaping and drying property; Under the high temperature, rely on to form M ₂S-MA pottery is in conjunction with obtaining certain high thermal resistance.Because binding substances is alkalescence, this system can be used for making magnalium or fireproof magnesia alumina spinel mould material.Usually, this system is unsuitable for aluminium silicon series refractory material.

For improving the performance of aluminium silicon based material, but silicon sol wedding agent and ALUMINA HYDRATE wedding agent have been studied.Silicon sol is SiO ₂Colloidalmaterial, solids content is 25-30%.In the colloidal sol, these are tiny, dispersive SiO ₂Particle is difficult for polymerization becomes the high strength material.During curing, silicon sol generation drying shrinkage, cracking.After the curing, silicon sol becomes loose porous material.But ALUMINA HYDRATE is a kind of with ρ-Al ₂O ₃It is the mixture of master's the steady alpha-alumina crystals of Jie.But the sclerosis of some ALUMINA HYDRATE is slow, demoulding strength particularly in physical strength after the warm processing very low.As require well to be shaped and heating properties, but silicon sol or ALUMINA HYDRATE need the admixture solidifying agent in conjunction with mould material.Like this, some silicon sol or ρ-Al ₂O ₃In conjunction with mould material actual be ultra-low cement deposit material, its CaO content is at 0.4-0.7%.Because eutectic is more, the improvement of such material at high temperature performance is little.

Another research direction is to adopt organic substance as wedding agent, as the gel casting technology.The principle of gel injection is to mix the organic monomer of lower concentration in high solid loading (〉=50%), low viscous slip, adds initiator again.Then, make above-mentioned monomer generation polymerization under certain condition, form firm three-dimensional crosslinking structure, slip is solidified, behind the demoulding, drying, binder removal and sintering, make the ceramic fire resistant goods again.Thus, gel injection has been avoided the impurity that uses inorganic bonding agent to introduce.But gel injection has brought new problem again: 1) some monomers (as third rare acid amides) are toxic substance, or produce toxic gas when burning.2) polymerization requires high to reaction conditions.Therefore, require the control production environment.3) in the thermal treatment, organically combine destroyed and ceramic combination when not forming as yet, the intensity of material is low.Therefore, this moment, material can not bear mechanical stress.So gel injection can be used for making fire resistive material product in the fire-resistant factory, but is difficult to be used for the changeable kiln engineering of field condition as the unshape refractory technology.

Summary of the invention

The objective of the invention is to invent a kind of composite fire mould material, the present invention proposes a kind of new combination: normal temperature, but rely on ALUMINA HYDRATE and micro-cement and polyacrylic acid reactant emulsion, generate polyacrylic acid aluminium (calcium) polymer in conjunction with phase.After the thermal treatment, above-mentioned polymer decomposes, and organic constituent wherein burns and loses, and inorganic component generation sintering forms ceramic combination.Thus, material of the present invention can obtain good to condense, sclerosis, the demoulding, drying and heating properties, is applicable to the high temperature kiln engineering that field condition is changeable.

Because of the impurity of wedding agent is reduced to bottom line, material has good temperature resistance.The main chemical reactions that invention relates to is as follows:

At first, carry out ρ Al ₂O ₃And cement (main component is CaOAl ₂O ₃) aquation; Then, be hydrate and polyacrylic chemical reaction.By formula 3)-4) high volence metal ion Al, Ca will replace the H on the emulsion carbonyl, and glue connects a plurality of polyacrylic acid molecules formation polyacrylic acid aluminium (calcium) three-dimensional frameworks.ρ-aluminum oxide also can be directly and the polyacrylic acid reaction.This is the principle that produces physical strength after condensation of materials, sclerosis and the oven dry.Simultaneously, reaction has the character of interfacial diffusion, thereby is convenient to control with chemical admixture.Relevant reaction is seen following various:

ρAl ₂O ₃+3H ₂O＝2Al(OH) ₃ 1)

2CaAl ₂O ₄+11H ₂O＝C ₂AH ₈+2Al(OH) ₃ 2)

Al(OH) ₃+3R-COOH＝(R-COO) ₃Al+1.5H ₂O 3)

C ₂AH ₈+3R-COOH＝2(R-COO) ₂Ca+(R-COO) ₃Al+9.5H ₂O 4)

In the thermal treatment, polyacrylic acid aluminium (calcium) decomposes, and organism burns and loses.Then, following solid state reaction takes place:

CaO+Al ₂O ₃+2SiO ₂＝CAS ₂ 5)

3Al ₂O ₃+2SiO ₂＝A ₃S ₂ 6)

By reaction formula 5～6: cement can condense, harden in improvement, improves demoulding strength, strengthens the sintering aspect and plays a role.But the volume of cement seldom even also can not water mixing mud.Generally speaking, the calcium oxide content that cement is brought into is about 0.1%, total calcium oxide content≤0.2% of material.So the mould material of inventing out still belongs to the non-cement mould material, has goodish high-temperature behavior.

In view of more than, the prescription that proposes invention is:

5-1mm corundum or bauxitic clay 40-56%

1-0.0088mm corundum or bauxitic clay 12-30%

d ₉₀＜0.088mm corundum or bauxitic clay 16-25%

αYang Hualv micro mist 0-5%

But ALUMINA HYDRATE 1-8%

Silicon ash 1-6%

Aluminous cement 0-2%

Add high efficiency water reducing agent (poly carboxylic acid+sulfonated naphthalene yuban+sulfonated melamine polymkeric substance) 0.05-0.4%

Add polyacrylic emulsion 1-6%

Add water 1-6%

Add heat-resistant steel fiber 0-3%

The feature of above raw material:

Described corundum is commercially available corundum refractory product, comprise fused corundom (compact alumina, white fused alumina, inferior white＜high alumina corundum and brown corundum), and alundum (tabular alundum, ordinary sinter corundum).

Described alumina is commercially available alumine refractory raw material.

Described αYang Hualv micro mist is commercially available refractory products of the same name, its particle diameter d ₅₀(account for total amount 50% small-particle in the powder and account for total amount 50% oarse-grained boundary size)≤8 microns.

But described ALUMINA HYDRATE is the commercially available prod, and its principal constituent is ρ-Al ₂O ₃The mixture of the steady alpha-alumina crystals of Jie.

Described silicon ash is commercially available refractory products.

Described aluminous cement is commercially available refractory cements, comprises Al ₂O ₃Content 80% and 70% aluminium 80 and aluminium 70 pure calcium aluminate refractory cementss.

Described high efficiency water reducing agent is commercially available cement water reducing agent, comprises sulfonated naphthalene yuban high efficiency water reducing agent, sulfonated melamine polymer high efficiency water reducer, and any cooperation of polycarboxylic acid series high efficiency water reducing agent.

Described polyacrylic emulsion is commercially available building polyacrylic acid emulsion, comprises building polyacrylic acid emulsion, building vinylformic acid and acrylate copolymer emulsion and vinylformic acid-acrylate-styrene terpolymer non-ionic water-soluble emulsion.The solids content 40-60% of emulsion, typical particle diameter 0.1-0.3 μ m, pH value 6-9.

Embodiment

Embodiment 1

Adopt the tabular alundum 52% of 5-1mm, 1-0.088mm tabular alundum 20%,＜0.088mm fused corundom 18%, alumina powder 3%, silicon ash 1.5%, aluminium 80 cement 0.5%, but ALUMINA HYDRATE 5%, add polycarboxylate water-reducer 0.1%, polyacrylic acid emulsion 3%, water 3% back companion and, obtain the slurry of good fluidity.After the shaping, slurry condensed in 0.5 hour, solidified in 1 hour, can the demoulding after 12 hours.Through 110 ℃ * 24H drying, sample obtains the folding strength of 14MPa, the compressive strength of 50MPa.Through the folding strength of thermal treatment in 1100 ℃ * 3 hours acquisition 11MPa, the compressive strength of 45MPa is burnt till line and is changed to 0.0%.Through the folding strength of thermal treatment in 1500 ℃ * 3 hours acquisition 17MPa, the compressive strength of 81MPa is burnt till line and is changed to 0.1%, refractoriness under load T _0.6=1510 ℃.

The calcium oxide content of bringing into because of cement only 0.1%, product of the present invention belongs to the composition range of non-cement refractory castable.This product has and significantly is better than the condensing of existing non-cement mould material, sclerosis, the demoulding, drying and heating properties and good high-temperature performance, and experiment has reached predetermined purpose fully.

Embodiment 2

Adopt the tabular alundum 42% of 5-1mm, 1-0.088mm tabular alundum 27%,＜0.088mm fused corundom 19%, alumina powder 3.5%, silicon ash 2.5%, aluminium 80 cement 1.0%, but ALUMINA HYDRATE 5%, add polycarboxylate water-reducer 0.1%, polyacrylic acid emulsion 3%, water 3% back companion and, obtain the slurry of good fluidity.After the shaping, slurry condensed in 0.5 hour, solidified in 1 hour, 12 hours with interior can the demoulding.Through 110 ℃ * 24H drying, sample obtains the folding strength of 20MPa, the compressive strength of 75MPa.Through the folding strength of thermal treatment in 1100 ℃ * 3 hours acquisition 18MPa, the compressive strength of 80MPa is burnt till line and is changed to 0.0%.

The calcium oxide content of bringing into because of cement only is 0.2%, and product of the present invention belongs to the composition range of ultra-low cement refractory castable.This product has and is better than the condensing of existing ultra-low cement deposit material, sclerosis, the demoulding, drying, heating and resistance to elevated temperatures, is suitable as that temperature height, the temperature difference are big, the wadding (as spray gun) at the serious position of fretting wear.

Mould material of the present invention can obtain good to condense, sclerosis, the demoulding, drying and heating properties, is applicable to the high temperature kiln engineering that field condition is changeable.

Claims (2)

1. composite fire resistant pouring material, work being characterised in that: the prescription of described mould material is:

5-1mm corundum or bauxitic clay 40-56%

1-0.0088mm corundum or bauxitic clay 12-30%

d ₉₀＜0.088mm corundum or bauxitic clay 16-25%

αYang Hualv micro mist 0-5%

But ALUMINA HYDRATE 1-8%

Silicon ash 1-6%

Aluminous cement 0-2%

Add high efficiency water reducing agent 0.05-0.4%

Add polyacrylic emulsion 1-6%

Add water 1-6%

Add heat-resistant steel fiber 0-3%

Described corundum is commercially available corundum refractory product, comprise fused corundom (compact alumina, white fused alumina, inferior white＜high alumina corundum and brown corundum), and alundum (tabular alundum, ordinary sinter corundum).

Described alumina is commercially available alumine refractory raw material.

Described αYang Hualv micro mist is commercially available refractory products of the same name, its particle diameter d ₅₀(account for total amount 50% small-particle in the powder and account for total amount 50% oarse-grained boundary size)=8 microns.

But described ALUMINA HYDRATE is the commercially available prod, and its principal constituent is ρ-Al ₂O ₃The mixture of the steady alpha-alumina crystals of Jie.

Described silicon ash is commercially available refractory products.

Described aluminous cement is commercially available refractory cements, comprises Al ₂O ₃Content 80% and 70% aluminium 80 and aluminium 70 pure calcium aluminate refractory cementss.

Described high efficiency water reducing agent is commercially available cement water reducing agent, comprises sulfonated naphthalene yuban high efficiency water reducing agent, sulfonated melamine polymer high efficiency water reducer, and any cooperation of polycarboxylic acid series high efficiency water reducing agent.

Described polyacrylic emulsion is commercially available building polyacrylic acid emulsion, comprises building polyacrylic acid emulsion, building vinylformic acid and acrylate copolymer emulsion and vinylformic acid-acrylate-styrene terpolymer non-ionic water-soluble emulsion.The solids content 40-60% of emulsion, typical particle diameter 0.1-0.3 μ m, pH value 6-9.