Baking-free brick and method for utilizing silicon sludge formed in polycrystalline silicon production to manufacture baking-free brick

Abstract

The invention discloses a baking-free brick and a method for utilizing silicon sludge formed in polycrystalline silicon production to manufacture the baking-free brick and belongs to the technical field of treatment for the silicon sludge formed during the polycrystalline silicon production process. The method for utilizing silicon sludge formed in polycrystalline silicon production to manufacture the baking-free brick provided by the invention comprises the following steps of: 1) dechlorinating and filtering the silicon sludge; 2) adding aggregates and cement into the silicon sludge, and carrying out compression moulding; and 3) naturally maintaining. An environment-friendly application capable of generating economic value is supplied to the treatment for the silicon sludge; the recycling of the wastes of the silicon sludge is realized; and the environment is protected. The baking-free brick provided by the invention comprises the following components by weight percent: 30%-60% of silicon sludge, 6%-8% of cement and the balance aggregates, wherein the water content of the silicon sludge is 10%-35% and the grain size of the aggregates is 0.5mm-10mm. The baking-free brick provided by the invention is practicable to reuse the silicon sludge; the wastes are reused; the environmental pollution is reduced; the cost is low; and the baking-free brick is suitable for being popularized.

Description

technical field [0001] The invention relates to the technology for treating the silicon mud formed in the polysilicon production process. Background technique [0002] In the production of polysilicon, waste gas that has no reuse value generally needs to be treated by hydrolysis. During the treatment of waste gas, a hydrolyzate that is slightly harmful to the environment can be obtained—silica mud, which is composed of silicon dioxide and water, and contains a certain amount of chloride ions. When there is less silica mud, it does not have any impact on production. However, as production continues, a large amount of silica mud can only be stacked or buried and cannot be reused. On the one hand, it consumes a lot of land for stacking, and the processing cost is high. On the other hand, silica mud contains a small amount of chloride ions, which will infiltrate after long-term stacking If it enters the groundwater, it will pollute the environment, so it is urgent to find a wa...

AI Technical Summary

Problems solved by technology

It uses the silica mud to make unburned bricks. By this method, silica mud can be made into unburned bricks, thereby solving the problem of high cost of silica mud treatment, and at the same time providing feasibility for the repeated use of silica mud. When it comes to the reuse of waste, the pollution of the environment is reduced. The unburned brick made of the silica mud is low in cost, easy to make, and can achieve a certain economic value, which is suitable for popularization and application.

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