High temperature resistant far infrared nano paint and preparation method thereof

Abstract

The invention relates to a high temperature resistant far infrared nano paint, which is made into porous ceramic with low heat conductivity and high infrared emission rate after sintering, and belongs to the technical field of high temperature resistant far-infrared paint. The component of the paint mainly comprises ZrO2, Cr2O3, Al2O3, Fe2O3, MnO2, Co2O3, MgO, Suzhou earth, bentonite, active carbon, and coal powder, and the high temperature resistant far infrared nano paint is prepared by grinding the raw materials into fine powder in nanometer stage (500nm or less), mixing them in proportion in the silicochromium aluminum composite sol and mixed solution of carboxy methyl cellulose, and forming a viscous suspension liquid. The paint can be sprayed or brushed onto the inner wall surface of the hearth after ash cleaning, and sintered in the temperature range of 900-1200 DEG C., so as to form a porous ceramic with certain strength, which is low in ceramic density, low in heat conductivity, high in 2.5-20 mu m full infrared wave band normal direction full emissivity (0.91-0.95).

Description

technical field [0001] The invention relates to a high-temperature-resistant far-infrared nano-coating and a preparation method thereof. The coating can be sintered at a relatively low temperature to form porous ceramics with low thermal conductivity and high emissivity in all infrared bands, and belongs to the technical field of high-temperature-resistant far-infrared coatings. Background technique [0002] After years of research and development, high-temperature infrared radiation materials have been successfully applied to various medium and high-temperature furnace linings and heating elements. Infrared radiation materials have high emissivity, fast heat transfer rate, and high heating quality. They are used in metallurgy, machinery, petrochemical and other industries. The high-temperature furnace inner wall coating can promote fuel combustion and optimize the temperature distribution in the furnace, which can save energy and protect the furnace lining. As a thermal ins...

AI Technical Summary

Problems solved by technology

[0003] Foreign infrared coatings mainly include ET-4 of British CRC Company, American CRC-10A, G-125 and SBE coatings, Japanese CRC1100, 1500 coatings, etc., as well as domestic patents CN 1114329A, CN 1131691A and CN 2195745Y, etc. Coatings have a certain energy-saving effect, but the following problems generally exist in different degrees: (1) The suspension and stability of the coating are poor, and the storage time is short; (2) The emissivity of the coating is unstable, and the emissivity decreases with the increase of temperature, such as With the increase of temperature, the emissivity of ET-4 paint decreases from more than 0.9 at 400°C to 0.84 at 1000°C; (3) The specific gravity of the paint is larger, the adhesion is weaker, and the thermal conductivity is higher

[0004] Patent CN 1552779A uses micro-nano ultra-fine powder to prepare high-temperature far-infrared coatings. The suspension and stability of the coatings are good, and it can be stored for a long time. However, it is mainly used in the metal inner wall of the boiler, and the thermal conductivity is high (0.977W / m· K), applied to the inner wall of the furnace lining will easily lead to an increase in the thermal conductivity of the furnace lining matrix, resulting in increased heat dissipation of the furnace body and energy consumption

[0005] Patent CN 2064770 uses a double-layer porous ceramic plate to increase thermal resistance, and CN 101113097A uses lightweight floating beads as a foaming agent to sinter to form a porous ceramic with low thermal conductivity. However, in the above two technologies, the double-layer porous ceramic plate and lightweight The manufacturing method of floating beads is relatively complicated, and the material of CN 101113097A patent has poor stability after mixing, and the coating is difficult to preserve for a long time