China's packaging waste types and resource utilization (3)

3.2.3 Plastic Packaging Waste: There are two main categories - plastic bottles and plastic films.

All countries in the world regard plastic recycling as the main development direction of plastic waste disposal in the world today, and the recycling rate of plastic packaging waste has reached about 42.5% in 2002 in the United States. Germany reached 70% in 2001. Nowadays, in order to facilitate recycling, many plastic manufacturers use the coding system developed by the plastics industry, with the symbol on the bottom of the bottle. Recycled used plastic bottles in other industries are constantly evolving. The need to process recycled PET into polyesters for the manufacture of textiles far exceeds the recovery capacity. The uses of recycled PVC include the manufacture of industrial strapping, highly wear-resistant wallcoverings, manufacturing of drains, wire conduits, electrical fittings and insoles, waste polypropylene and high-density polyethylene for outdoor and street use Benches, chairs, picnic tables, turnover boxes, signs, support frames, etc. The recovered HDPE bottle can be processed into a recycled material, used between the inner layer and the outer layer made of opaque HDPE resin, and co-extruded and blown into plastic bottles containing oil, detergent and the like; the plastic film is generally larger than the plastic bottle. Difficult to recover and difficult to recycle, but they can be burned as energy for recycling. The waste plastics oiling technology uses high-performance catalysts to "depolymerize" high-density polyethylene or polypropylene plastics to produce diesel and gasoline that meet the national standards, and the oil production rate reaches over 75%.

3.2.4 Steel and metal packaging waste: These two types of packaging waste have a long recycling time.
For example, many garbage plants are equipped with electromagnetic suction devices, and the use of magnetic absorption method to recover steel and metal, its use is more extensive. Such as aluminum can be made of recycled raw materials, production of bicycle rims, aluminum plate packaging, etc.; tinplate can be made into industrial automation steel, cans, boxes and so on. According to the statistics of the material department, in the past 40 years, China has recycled more than 300 million tons of scrap steel and scrap steel more than 3 million tons. The value of recycling can be imagined.

3.2.5 Glass packaging waste: Waste glass can be processed into glass, high-quality insulation materials used in construction or prefabricated components.

3.2.6 Composite material packaging waste: Waste composite materials can also be used as paper scrap, tear-resistant paper, corrugated paperboard, core board, textile tissue paper, paper backpack, etc. after recycling.

3.3 Incineration and energy reuse: Plastics have the highest energy values. Some countries in Japan and Europe mainly generate electricity through incineration. Belgium and other countries provide industrial steam through incineration. They believe that the recovery of incineration heat energy is a recycling of plastic waste. The important approach is also the most realistic means of managing plastic waste. The main components of pyrolysis-produced wood gas are carbon dioxide, carbon monoxide, methane, ethylene, hydrogen, etc. It is an excellent gaseous fuel that does not pollute the environment.

3.4 Composting: Some packaging products are difficult to separate after being crushed but are also rich in organic matter. For example, waste paper scrap, wood chips, fiber materials and biodegradable plastic waste are mixed with other substances and then composted by microbial fermentation. Make organic compound fertilizer.

4 Conclusion

It can be expected that the recycling economy triggered by the recycling of waste will form a large-scale industry in the future and it will have an attractive development prospect. It will certainly make a useful contribution to the rational use of resources, the protection of the ecological environment, the development of a recycling economy of resources, and the promotion of sustainable economic development. Although there are many ways to utilize waste packaging resources, it is after all a secondary use. With the limitations of various factors, waste is inevitable. Therefore, we advocate green packaging, try our best to reduce, lighten, or thin the packaging, eliminate excessive packaging, research and develop packaging materials that are degradable or edible, reduce waste of resources, and make the whole society recognize the recycling economy. The importance of attention to resources, care for the environment, the rational use of limited resources.

(Guo Caifeng Xu Bo)

Chinese packaging