Industrial production device and method for producing nanometer SiO2 rice hull ash

Abstract

The invention discloses an industrial production device and an application method for producing nanometer SiO2 rice hull ash. The industrial production device comprises a fluidized bed boiler, a cyclone separator, a heat exchanger and a bag-type dust collector; and the fluidized bed boiler has the characteristics of adoption of a section-variable hearth, sectional type temperature control and air distribution, adoption of a secondary air system and rise of a dilute phase area. The running temperature of the fluidized bed boiler is 670-720 DEG C, the running wind-speed of the fluidized bed boiler is 0.9-1.4m / s and the excess air coefficient of the fluidized bed boiler is 1.16-1.21. According to the industrial production device, the self energy of rice hulls can be effectively utilized for supplying heat, the thermal efficiency of the boiler is improved, the energy sources are saved, the SiO2 rice hull ash with a high-purity nanometer structure can be produced, and the stability of reaction conditions is ensured. Proved by experiments, the produced rice hull ash contains more than 90 percent of amorphous high-purity SiO2 which is in a form of 15-30nm nanoparticles.

Description

technical field [0001] The present invention relates to the preparation of nanostructured SiO 2 of rice husk ash, particularly relating to a nanostructured SiO 2 An industrialized production device of rice husk ash and a method for using the same. Background technique [0002] my country's annual rice output is about 200 million tons, accounting for 1 / 3 of the world's total output, ranking first in the world. Rice husk is a by-product of rice processing, accounting for about 20% of the weight of rice grains, and produces about 40 million tons of rice husk every year, which is a huge resource. A large number of rice husk resources have not been fully utilized. In rural areas, field burning is the main treatment method, which pollutes the environment and wastes energy. In recent years, studies have shown that rice husk ash contains about 20% amorphous SiO 2 , which has high activity and is an additive for building materials. After purification, it can be used as industrial...

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Problems solved by technology

[0003] The invention patent of application number 93116790.6 "the device for producing active rice husk ash" introduces the method of preparing rice husk ash by intermittent incineration device, but this technology has the following disadvantages: 1. It cannot feed continuously, and the two-step method is complicated to operate, and it is not It is beneficial to the promotion of industrialization; 2. The energy of the rice husk itself is not fully utilized, resulting in energy waste

The invention patent of application number 200410026459.5 "a rice husk incineration device and its output nano-structure SiO2 rice husk ash" uses a closed rice husk incineration device to prepare nano-structure SiO2 rice husk ash. The heat released by the combustion of rice husks is limited by the closed incineration device, which cannot continuously feed materials, and it is difficult to solve problems such as industrialization promotion.

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