Foam equipment-foam machinery and equipment-recycling

　　As a feasible method of reconciling EPS and the environment, chemical recycling has attracted the attention of various countries. The method is to decompose waste EPS into reusable components such as monomers, compounds, and fuels, making EPS recycling a truly closed-loop process. Compared with mechanical recycling, this method has the following advantages: the quality of the chemical raw materials generated by decomposition can be comparable to that of new materials; in addition, it has the potential to treat a large amount of waste, which can realize the re-resource and achieve the real pollution of EPS to the environment. . The processes with industrialization potential in current chemical recovery are cracking, vaporization, hydrogenation, and pyrolysis.

　　Although chemical recovery is not new in terms of reaction mechanism, there are still many engineering problems that need to be solved if it is to be put into practical use.

　　1. Anti-foaming and reducing volume treatment for

　　Past experience, the key to the EPS waste treatment method is to defoam and reduce the volume on the spot. Transporting the recovered materials that have been restored to a density close to the density of the new material polystyrene to various places of use can save a lot of transportation costs. After the EPS waste is defoamed, the volume of the material calculated by density is only about 3% of the original EPS foam machinery. The material obtained by defoaming has good properties and can be directly used as a raw material for plastic processing, and can also be used for other purposes such as adhesives and coatings. The defoaming recovery equipment is simple and easy to operate. It can also be designed into a vehicle-mounted form to facilitate mobile recovery at various EPS recovery centers.

　　2. Making chemical products

　　The EPS foam machinery can be dissolved in organic solvents such as aromatic hydrocarbons and halogenated alkanes, and the waste EPS foam machinery can be made into coatings or adhesives. Some manufacturers have tried to put EPS foam machinery, benzene and kerosene into the kettle in a certain proportion, heat and stir to melt, and then add an appropriate amount of inorganic fillers and inert materials to make a modified waterproof material. The disadvantage of this use is: Due to the weak polarity of the EPS macromolecular structure, it has low adhesion to other materials when used as a coating and adhesive, and can only be used for rough-surfaced items such as concrete and paper products. Utilizing the properties of EPS that can be dissolved in asphalt and rosin, waste EPS foam machinery is used to change the melting point of asphalt, increase the strength of asphalt, improve the phenomenon of asphalt cracking in winter and summer stickiness, and overcome the shortcomings of rosin brittleness.

　　(1) Waterproof coating used to make paper boxes

　　Because the polystyrene molecule has no hydrophilic group, the water absorption rate (0.06%) is low, and it can maintain the strength and size in a humid environment, so it can be used as a waterproof coating. Generally, it is first formulated into an emulsion, the diameter of the latex particles is about 0.01 μm to 5.00 μm, and each rubber particle contains many macromolecular chains. When the ambient temperature during painting is higher than the minimum film forming temperature, the coating is applied to the surface of the object to be coated. After the water volatilizes, many macromolecules in the latex particles penetrate and diffuse each other, coalescing and cross-linking to form a continuous transparent film. When the ambient temperature is lower than the minimum film-forming temperature, the coating is applied to the surface of the coated object. After the water volatilizes, the latex particles become discrete particles and cannot be glued together, making the surface of the coated object chalky. The lowest film-forming temperature can be determined by experiment. The coating can form a film at normal temperature.

　　(2) Used in the manufacture of architectural coatings

　　Using waste EPS as the base material, the mixture of cellulose acetate, polyvinyl chloride copolymer, phenolic resin, and xylene cyanate as modifier, with other additives and fillers, can be used to produce interior wall waterproof coatings and exterior wall coatings , Floor coatings.

　　3. Depolymerization regeneration (manufacturing styrene monomer)

　　The defoamed waste EPS foam is mechanically crushed to 3mm～5mm particles, which can be used to prepare styrene monomer. The weaker link in the styrene polymer happens to be the continuous bond of each monomer, which is heated at high temperature to generate the styrene monomer, that is, the depolymerization process.