Disclosure of Invention
Aiming at the prior art, the invention aims to provide the environment-friendly fireproof coating prepared by taking the solid waste in the steel industry as the raw material. The environment-friendly fireproof coating is a novel non-intumescent fireproof coating, has the advantages of light weight, low cost, easy production, simple and convenient construction, environmental protection, safety, good fireproof effect and high cost performance, can be used as an ultra-thin and thin fireproof coating, and can be widely used for fireproof protection in different fields such as steel structures, concrete structures and the like.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides an environment-friendly fireproof coating, which is prepared from the following raw materials in parts by weight:
30-35 parts of cement, 6-10 parts of mica powder, 5-7 parts of modified sodium silicate powder, 12-18 parts of steel slag powder, 4-8 parts of water slag powder, 25-35 parts of fly ash floating beads and 2-4 parts of hydrophobic silicon dioxide.
Preferably, the environment-friendly fireproof coating is prepared from the following raw materials in parts by weight:
32 parts of cement, 8 parts of mica powder, 7 parts of modified sodium silicate powder, 15 parts of steel slag powder, 5 parts of granulated slag powder, 30 parts of fly ash floating beads and 3 parts of hydrophobic silicon dioxide.
Preferably, the cement is one or two of aluminate cement and portland cement; more preferably, the cement is a aluminate cement.
Preferably, the mica powder is sericite powder. The sericite powder is different from other mica powder, and has good dispersion and suspension property in an aqueous medium, fine white particles and good heat resistance and insulativity.
Preferably, the mesh number of the steel slag powder is 300-400 meshes.
Preferably, the grain slag powder has a mesh number of 400-500 meshes.
Preferably, the mesh number of the fly ash floating bead is 30-100 meshes.
The second aspect of the present invention provides a method for preparing the environment-friendly fire retardant coating, comprising the following steps:
and uniformly mixing the cement, the mica powder, the modified sodium silicate powder, the steel slag powder, the grain slag powder, the fly ash floating beads and the hydrophobic silicon dioxide to obtain the water-based paint.
In a third aspect of the present invention, there is provided the use of the above-mentioned environmentally friendly fire retardant coating for fire protection of metal members, fire protection of concrete members and/or fire protection of tunnels.
In the application, the environment-friendly fireproof coating and water are mixed according to the weight ratio of 1: (0.4-0.5) uniformly mixing to obtain slurry; coating the slurry on the surface of a base material, and maintaining for 7-10 days;
the substrate is a material to be protected against fire, such as metal members, concrete members, tunnel walls and vaults.
Preferably, the slurry is coated on the surface of the substrate to a coating thickness of 3 to 7 mm.
Preferably, the coating is by spraying or wiping.
The invention has the beneficial effects that:
the environment-friendly fireproof coating prepared by the invention has the following characteristics:
(1) the main raw materials of the product are solid wastes generated in the steel industry, including steel slag, water granulated slag and fly ash, which account for more than 50% of the raw materials for preparing the environment-friendly fireproof coating, so that the resource utilization of the bulk solid wastes of steel is realized, and the environment-friendly fireproof coating conforms to the principle of environment protection and sustainable development.
(2) The product has light weight, low cost, easy production, simple and convenient construction, environmental protection, safety, good fireproof effect and high cost performance.
(3) The product is a non-expansive fireproof coating, is easy to maintain and reform after disasters, and has wear resistance, crack resistance, aging resistance and long service life.
(4) The product is solid powder, and is convenient to store and transport.
(5) The product can form an effective fireproof insulating layer when the coating thickness is 3-7mm, the high temperature resistance reaches about 1500 ℃, the fire resistance limit reaches more than 2-3 hours, and casualties and economic loss caused by major fire accidents can be effectively prevented.
(6) When a fire disaster occurs, the product can not release toxic gas and substances, can not cause casualties and environmental pollution due to the toxic gas, and is safer and more environment-friendly to use.
Detailed Description
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
As described in the background art, the steel industry has a large amount of solid wastes and is difficult to reuse resources, which causes environmental pollution.
In order to solve the problem of recycling of solid waste resources in the steel industry, the invention creatively takes the solid waste in the steel industry as the main raw material to prepare the fireproof coating, thereby realizing the recycling of the solid waste in the steel industry and being beneficial to the environmental protection; and the prepared fireproof coating product has good economic value, and the added value of the solid waste in the steel industry is improved.
The existing fire-retardant coating can be divided into an intumescent fire-retardant coating and a non-intumescent fire-retardant coating according to a fire-retardant mechanism; it can be divided into thick-coating type fire-retardant coating, thin-coating type fire-retardant coating and ultra-thin type fire-retardant coating according to thickness. The thick-coating fireproof coating is basically a non-intumescent fireproof coating, the main components of the thick-coating fireproof coating are inorganic salts, a flame-retardant binder and an inorganic fiber reinforcing filler, the fireproof principle of the thick-coating fireproof coating is that the inorganic compound is utilized, the heat conductivity coefficient is low, the thick-coating fireproof coating has good heat insulation performance, and the fire resistance limit can be as long as 3 hours; the disadvantages are thick coating, large specific gravity, unsmooth coating surface, bad decorative property, easy moisture absorption, cracking and powder removal. The thin-coating type fireproof coating and the ultra-thin type fireproof coating are basically expansion type fireproof coatings, the fireproof principle is that expansion heat-insulating property is utilized, when the thin-coating type fireproof coating and the ultra-thin type fireproof coating are heated, foaming expansion is carried out, a thick honeycomb-shaped compact porous carbon layer is formed, and the purpose of heat insulation is achieved due to the fact that the thermal conductivity of the carbon layer is low; however, the existing intumescent fire-retardant coating is mainly composed of organic materials, can generate harmful gases and toxic substances at high temperature, is sensitive to humidity, has quick performance attenuation and low fire resistance limit, and has great harm to human health in the production and construction processes.
Based on the above, the invention aims to provide a novel environment-friendly fireproof coating. The environment-friendly fireproof coating is prepared by taking solid wastes in the steel industry as main raw materials, and is a non-intumescent fireproof coating. The non-intumescent fire-retardant coating is different from the existing non-intumescent fire-retardant coating, the environment-friendly fire-retardant coating can be used as a thin coating type and an ultrathin type fire-retardant coating, an effective fire-retardant insulating layer can be formed when the coating thickness is 3-7mm, the high temperature resistance reaches about 1500 ℃, and the fire-retardant limit reaches more than 2-3 hours.
As described above, conventional thin-coat type and ultra-thin type fire retardant coatings utilize intumescent heat insulating properties to achieve fire protection. The fire-retardant coating is a non-expansion type fire-retardant coating, the fire resistance and the heat insulation of the coating are utilized, the non-expansion type fire-retardant coating is used as a thin coating type and an ultra-thin type fire-retardant coating, the requirement on the product performance of the coating is higher, and the design difficulty of the product is higher.
In addition, the environment-friendly fireproof coating is a pure inorganic water-based fireproof coating, and the commercially available ultrathin fireproof coating is a coating composed of ethyl cellulose, paraffin oxide, fireproof material, an additive, an oily solvent and the like, and the solvent is inflammable, so that toxic and irritating gases and peculiar smell are easily generated during construction; although the thin fireproof coating is mostly called water-based coating. However, the base material emulsion mostly adopts four kinds of pure acrylic emulsion, silicone acrylic emulsion, styrene-acrylic emulsion or EVA emulsion as the base material, and these are all organic components. Compared with the prior art, the environment-friendly fireproof coating disclosed by the invention takes water as a solvent, so that the environment-friendly fireproof coating is more economical and environment-friendly to use.
The fire-retardant coating is further different from the existing fire-retardant coating in that: the environment-friendly fireproof coating can be applied to the fire prevention of steel structures, high-rise buildings, tunnels of roads and railways, petrochemical engineering and underground garages. It is known that the performance requirements of fire-resistant coatings may vary depending on the environment of application, for example, tunnels are mostly in mountainous areas, tunnels are shady, moist, and have poor ventilation. The inner wall of the concrete is easy to damp, mildew, alkali return, shedding and the like, so that the fireproof coating of the tunnel needs to consider the excellent fireproof performance, the waterproof performance, the mildew-proof property, the bonding strength, the aging resistance and the construction convenience and safety. The environment-friendly fireproof coating disclosed by the invention is very excellent in water resistance, acid resistance, alkali resistance, cold and hot cycle resistance, fire resistance, bonding strength and the like, so that the environment-friendly fireproof coating disclosed by the invention can be applied to fireproof protection of different scenes.
In one embodiment of the invention, the environment-friendly fireproof coating is prepared from the following raw materials in parts by weight:
30-35 parts of aluminate cement, 6-10 parts of sericite powder, 5-7 parts of modified sodium silicate powder, 12-18 parts of steel slag powder (300 meshes-400 meshes), 4-8 parts of granulated slag powder (400 meshes-500 meshes), 25-35 parts of fly ash floating beads (30 meshes-100 meshes) and 2-4 parts of hydrophobic silica.
In the environment-friendly fireproof coating, the raw materials are an inorganic whole, the defects are overcome, and the raw materials have a synergistic effect, wherein the steel slag powder, the grain slag powder and the fly ash floating beads are all derived from solid wastes in the steel industry, and have the characteristics of good fire resistance, low heat conductivity coefficient, small water absorption rate and the like, particularly the fly ash floating beads are of a closed-hole hollow structure, light weight, high strength, wear resistance, high temperature resistance, insulation and flame retardance. The aluminate cement, the sericite powder and the modified sodium silicate powder are combined together, so that the modified sodium silicate cement has the advantages of high temperature resistance, strong adhesive force, high bonding strength, high compressive strength, good crack resistance, small thermal expansion coefficient, good wear resistance, good water resistance and the like, and particularly the viscosity, the water resistance and the strength of the aluminate cement can be increased by matching the modified sodium silicate with the aluminate cement. The hydrophobic silica can further enhance the water resistance of the environment-friendly fireproof coating, but because the environment-friendly fireproof coating takes water as a solvent, the addition amount of the hydrophobic silica is very critical, and if the addition amount is too small, the improvement on the water resistance of the fireproof coating is limited; if the addition amount is too large, the tackiness of the fireproof coating is affected; through a plurality of tests, the hydrophobic silicon dioxide with the addition amount of the invention has the best effect.
In conclusion, the environment-friendly fireproof coating prepared by optimizing the selection and the dosage of the raw materials has excellent fireproof performance, good water resistance, low thermal expansion coefficient, easy reconstruction and maintenance after disasters and excellent durability. More importantly, the environment-friendly fireproof coating can be suitable for a plurality of different application scenes such as metal member fire prevention, concrete member fire prevention, tunnel fire prevention and the like.
In order to make the technical solutions of the present application more clearly understood by those skilled in the art, the technical solutions of the present application will be described in detail below with reference to specific embodiments.
The raw materials used in the examples and comparative examples of the present invention are conventional or existing materials in the art, and are commercially available.
Example 1: preparation of environment-friendly fireproof coating
1. The raw materials comprise:
30 parts of aluminate cement (525 type), 8 parts of sericite powder, 7 parts of modified sodium silicate powder, 15 parts of steel slag powder (300 meshes), 5 parts of granulated slag powder (400 meshes), 32 parts of fly ash floating beads (30 meshes) and 3 parts of hydrophobic silicon dioxide.
2. The preparation method comprises the following steps:
the raw materials are fully mixed and evenly stirred to prepare the environment-friendly fireproof coating.
3. The using method comprises the following steps:
mixing the prepared environment-friendly fireproof coating and water according to the weight ratio of 1: (0.4-0.5) uniformly mixing to obtain slurry; coating the slurry on the surface of the base material, and curing for 7-10 days.
Example 2: preparation of environment-friendly fireproof coating
1. The raw materials comprise:
32 parts of aluminate cement (525 type), 5 parts of sericite powder, 5 parts of modified sodium silicate powder, 10 parts of steel slag powder (400 meshes), 10 parts of granulated slag powder (500 meshes), 35 parts of fly ash floating beads (100 meshes) and 3 parts of hydrophobic silicon dioxide.
2. The preparation method comprises the following steps:
the raw materials are fully mixed and evenly stirred to prepare the environment-friendly fireproof coating.
3. The using method comprises the following steps:
mixing the prepared environment-friendly fireproof coating and water according to the weight ratio of 1: (0.4-0.5) uniformly mixing to obtain slurry; coating the slurry on the surface of the base material, and curing for 7-10 days.
Example 3: preparation of environment-friendly fireproof coating
1. The raw materials comprise:
33 parts of aluminate cement (525 type), 6 parts of sericite powder, 7 parts of modified sodium silicate powder, 12 parts of steel slag powder (300 meshes), 8 parts of granulated slag powder (400 meshes), 30 parts of fly ash floating beads (50 meshes) and 4 parts of hydrophobic silica.
2. The preparation method comprises the following steps:
the raw materials are fully mixed and evenly stirred to prepare the environment-friendly fireproof coating.
3. The using method comprises the following steps:
mixing the prepared environment-friendly fireproof coating and water according to the weight ratio of 1: (0.4-0.5) uniformly mixing to obtain slurry; coating the slurry on the surface of the base material, and curing for 7-10 days.
Comparative example 1:
1. the raw materials comprise:
32 parts of Portland cement (525 type), 8 parts of sericite powder, 15 parts of steel slag powder (300 meshes), 5 parts of granulated slag powder (400 meshes) and 30 parts of fly ash floating beads (30 meshes).
2. The preparation method comprises the following steps:
and fully mixing the raw materials, and uniformly stirring to prepare the fireproof coating A.
Comparative example 2:
1. the raw materials comprise:
32 parts of Portland cement, 8 parts of talcum powder, 7 parts of modified sodium silicate powder, 25 parts of steel slag powder (300 meshes), 25 parts of granulated slag powder (400 meshes) and 3 parts of hydrophobic silicon dioxide.
2. The preparation method comprises the following steps:
and fully mixing the raw materials, and uniformly stirring to prepare the fireproof coating B.
Comparative example 3:
1. the raw materials comprise:
30 parts of calcium hydroxide, 10 parts of silica sol, 0.1 part of sodium chloride, 5 parts of aluminum hydroxide, 3 parts of sepiolite and 3 parts of bentonite.
2. The preparation method comprises the following steps:
and mixing the raw materials with 100 parts of water, and performing high-speed dispersion and filtration to obtain the fireproof coating C.
Test example 1:
q235 steel is used as a substrate, rust is thoroughly removed, rust prevention treatment is carried out according to specified rust prevention measures, and the fireproof coatings prepared in example 1 and comparative examples 1 to 3 are respectively coated on the surface of the substrate.
The performance indexes of the fireproof coating are tested according to the method of GB14907-2002, and the method comprises the following steps: bond strength, water resistance, resistance to cold and heat cycles, acid resistance, alkali resistance, and fire resistance. The results are shown in tables 1 to 6.
Table 1: bond Strength test results
Table 2: water resistance test results
Table 3: test results of Cold-Heat cycling resistance
Table 4: results of acid resistance test
Table 5: alkali resistance test results
Table 6: test results of fire resistance
Test example 2:
the cold-rolled ribbed prestressed concrete hollow slab is used as a bottom plate for testing, the fireproof coatings prepared in the example 1 and the comparative examples 1 to 3 are uniformly coated on the lower surface of the bottom plate for testing to a fixed thickness, and then the bottom plate is placed in a ventilated and dried indoor natural environment for maintenance.
The performance indexes of the fireproof coating are tested according to the technical requirements of the concrete constructed fireproof coating in GA98-2005, including bonding strength, water resistance, alkali resistance, cold and hot cycle resistance test and fire resistance. The results are shown in tables 7 to 11.
Table 7: bond Strength test results
Table 8: water resistance test results
Table 9: alkali resistance test results
Table 10: test results of Cold-Heat cycling resistance
Table 11: test results of fire resistance
As can be seen from the test examples 1 and 2, the environment-friendly fireproof coating completely meets the performance requirements of steel structure fireproof coatings and concrete structure fireproof coatings, and can meet the fireproof requirements of a plurality of different scenes.
As can be seen from tables 1 to 11, when the composition of the raw materials of the environment-friendly fire retardant coating of the present invention is reduced or changed, the fire retardant property, water resistance, adhesive strength, acid resistance, alkali resistance, etc. of the prepared fire retardant coating are significantly reduced. Especially, in the case of the proportion 3, the performance requirements of the thin fireproof coating and the ultrathin fireproof coating can not be met by adopting the existing fireproof coating prepared from inorganic raw materials.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.