Synthetic plastics have made tremendous contributions to promoting industrial development and improving people's living standards. In the early days of the development of the plastics industry, the chemical stability of synthetic materials is one of the most concerned and important research topics. After several decades, its stability has been well resolved. Dramatically, its stability has become an important reason hindering its further development. “Agricultural film†is a good example. Because it is difficult to be biodegraded, it can only be used once. The easiest way to deal with it is to burn it. This not only wastes resources, but also causes air pollution.
The recycling and utilization of waste plastic products has become a worldwide issue. Traditional landfill and incineration processes are being replaced by reuse, degradation or decomposition processes. The recycling of waste plastic products not only protects the environment, saves energy, but also has good economics.
Sound insulation material
After the waste foam is pulverized, it is heated by infrared irradiation to reduce its volume to less than 1/20; and then mixed with special cement to make a "rice sugar"-like building material. This building material has an average of 60% noise reduction and 90% noise suppression for certain frequencies. This material has now been used as a wall and ceiling for soundproofing of power stations.
Manufacture of lightweight roofing insulation
The waste expanded polystyrene is pulverized, added with expanded perlite and cement, mortar, stirred and mixed evenly, cured on the roof for 3 days, naturally dried, and then smoothed with a cement mortar into a lightweight concrete insulation layer. The material produced by the method has low production cost, good heat preservation property, and the house is warm in winter and cool in summer.
The production process is as follows: the waste expanded polystyrene is washed, pulverized to a particle size of 0.1 cm to 0.5 cm, and 32.5 grade Portland cement is added, and the volume ratio of the two is 2:1 to 3:1, and the mass ratio is 1% to 3% of early strength agent (inorganic alkali), stirred with water to form a slurry, adding rosin soap foaming agent, and then stirring into a slurry, into the mold, demoulding after 1 hour, curing for 7 days, making 10cm thick The heat transfer coefficient and compressive strength of the plate are good, and the heat preservation performance can reach the heat preservation effect of the clay brick wall with a thickness of 95 cm. When using the roof, apply a layer of cement mortar on the board, use water to maintain, and then use asphalt felt to make waterproof layer.
Manufacturing waterproof membrane
Washing and drying the waste expanded polystyrene, dissolving it with cheap phenol or chlorohydrocarbon residue, adding a toughening agent and a film-forming anti-seepage anti-wear agent to form a viscose, which is blown or coated on the surface of the glass cloth. Dry to roof waterproofing or waterproofing membranes for pipes. The solvent can be recycled by cooling.
It is worth noting that both chemical methods and physical methods are faced with a major difficulty, that is, the recycling of waste plastics is mixed, it is difficult to identify the classification, on the other hand, it is particularly dirty, the cleaning is very difficult, and the operating cost is high. Therefore, the enthusiasm of the manufacturers is not high.
There are two main solutions at present: limiting the production of multi-component plastic products and improving the level of classified collection and tillering. In the past, in order to protect the beverages such as juice from the bottle from ultraviolet rays, the manufacturer will use blue and green plastic bottles. At present, it is considered that the transparent treatment of ultraviolet rays is to cover all the transparent bottles with labels, leaving A small hole in the needle of the sewing machine for easy peeling.
In addition, tillering is an important factor in determining the economics of material reuse. At present, foreign branching technology has developed rapidly, and many automated branching lines have been put into use, which can be used to accurately classify different types of materials.
Aluminium High Speed Spiral Door
Dongguan HengTaichang Doors Co, Ltd. , https://www.dghtcdoor.com