Novel method for recovering waste and old polystyrol

Abstract

The invention discloses a novel technology for recycling waste polystyrene with low cost. The technology is as follows: low-temperature hot pressing is performed on the waste polystyrene; the waste polystyrene is dissolved in good solvent of polystyrene; insoluble impurities are primarily filtered and removed; decolorization is performed; precipitator is added for precipitation; secondary filtration is performed and other technological processes; the waste polystyrene is reclaimed and polystyrene granules are regenerated; simultaneously, micro nucleating agent is added by the means of low-temperature cooling to realize high-efficiency separation of the solvent and the polystyrene precipitator, and the polystyrene granules are reclaimed; and the reclaimed granules can be used for continuous production of polystyrene downstream products. The technology can highly efficiently realize effective separation of the solvent and the precipitator, thereby greatly improving the quality of polystyrene reclaimed by adoption of the technology and the solvent recovery rate, and greatly reducing the polystyrene cost of recovering the polystyrene. The technology has the advantages of short technological flow, high production efficiency, low solvent consumption, high product quality, low energy consumption, no secondary pollution caused, environmental protection and so on, and has important industrial application value.

Description

technical field [0001] The invention relates to the field of polymer materials, in particular to the recovery technology of waste polystyrene. Background technique [0002] With the development of the economy, the lack of resources has become increasingly prominent, and the regeneration and reuse of waste materials is very important. Among various plastics, polystyrene (PS) and expanded polystyrene (FPS) are widely used. In recent years, the global consumption of polystyrene exceeds 10 million tons per year, of which expanded polystyrene exceeds 2 million tons. tons, with an increasing trend year by year. What is worrying is that this kind of waste products cannot be degraded even under natural conditions for 200 years. As a result, the existing polystyrene may have an impact on the living environment of several generations or even a dozen generations. Currently, waste such as polystyrene is increasing day by day , has caused serious "white pollution" and led to the deteri...

AI Technical Summary

Problems solved by technology

At present, although there are many methods for recovering polystyrene, the method for high-grade polystyrene that has commercial value is mainly the solvent recovery method. For example, my country's patent CN00108071.7 introduces a method for recycling waste polystyrene. However, this method only adopts a simple solvent recovery method, which is difficult to effectively remove the organic impurities of waste polystyrene, so the quality of the recovered polystyrene is low; patent CN200410055555.2 introduces a method using a good solvent as solvent to dissolve waste polystyrene, and then use vacuum spray drying to regenerate polystyrene, but this method also has problems such as incomplete removal of impurities, complicated equipment, and high energy consumption; patent CN100420059138.5 introduces a direct The simple recycling process of crushing and mechanical dust removal, the recycled products are variegated or opaque, and are usually used to manufacture non-food contact products. The quality of such recycled products is far from meeting the application needs of packaging materials and food contact products; patent CN200510032267.X introduces a method of recycling waste polystyrene by using limonene, but the solvent is expensive and has no industrial value; patent technology CN86100803 introduces a method of recycling waste polystyrene by using fatty alcohol as an extraction agent , but this process has problems such as long process flow, high requirements on equipment, and large energy consumption.

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