Method for expanding open-bore perlite by gas indirect heating

Abstract

The invention discloses a method for expanding open-bore perlite by gas indirect heating, which heats the open-bore perlite in a gas indirect heating mode. The method comprises the following step: a. a gas indirect heating expansion furnace comprising an expansion cylinder (3) with a small upper cylinder and a big lower cylinder is used; b. the open-bore perlite expands in a high temperature area(5) of the small expansion cylinder in the furnace chamber, so that the perlite micropowder loses crystal water, quickly expands and increases the volume; c. the expanded perlite quickly enters in a low temperature area (8) in the big cylinder to gradually drop temperature without sticking to the wall; d. a draft fan absorbs high temperature waste gas in the furnace chamber through a high temperature flue (6), so that the temperature of the low temperature area in the big cylinder drops, and the form of the perlite is defined; and the discharge end uses a graded closed-loop separating system to ensure no pollution on the environment. The method solves the problem of difficulty in the expansion of the perlite micropowder with 100-250 meshes, has the advantages of short expansion range of balls, quick product discharge, high efficiency, no sticking to the furnace, and low equipment investment, and is suitable for the expansion and the separation of large granules and micro granules.

Description

technical field [0001] The invention relates to the technical field of expansion furnaces, in particular to a gas-fired indirect heating perlite expansion method. Background technique [0002] At present, perlite is an acidic volcanic glass lava, brittle in nature, with pearl luster and grease luster, special arc cracks, hardness 5.5-7, density 2.2-2.4g / cm3. The expansion multiple can reach more than 7 to 30 times, and the refractoriness is as high as 1300 to 1380 °C. After crushing, sieving, preheating and roasting, it becomes a porous granular material --- expanded perlite, which can be used with different cementing agents to make perlite products of various properties and properties, with light weight and thermal conductivity. Low performance, strong sound absorption, no corrosion, no combustion, acid and alkali resistance, non-toxic and tasteless, etc., are high-efficiency and ultra-light heat preservation, heat insulation, sound insulation, decorative materials, widely...

AI Technical Summary

Problems solved by technology

[0006] In order to solve the above-mentioned problem that the existing open-cell and closed-cell expansion furnaces cannot expand perlite powder below 100-250 mesh, the present invention provides a method for indirect heating of perlite powder by gas-fired expansion, which can solve the problem of discharging perlite powder. Separation, cooling and collection of beads and gas waste gas, short expansion stroke of beads, fast discharge, high efficiency, no furnace sintering, suitable for expansion and separation of large particles and microscopic particles

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