The relatively scarce resources in Japan have prompted it to pay more attention to garbage classification and recycling, in order to achieve resource utilization and reduce land waste caused by landfilling. In the 1980s, Japan began implementing a strategy to control the growth of waste and shifted waste management from end of pipe treatment to front-end control. One of the measures was to implement garbage classification and collection. Generally, garbage is divided into three categories: combustible, non combustible, and resource-based (metal, paper, glass, fabric, etc.). At the same time, some cities are also subdivided into more than ten subcategories, and the plastic category is even subdivided into as many as nine subcategories. Figure 3-4 shows the classified garbage bins on the streets of Japan. At present, cities such as Nagoya, Hokkaido, and Yokohama in Japan have developed targeted garbage collection systems based on their own urban and population characteristics.
The Japanese resource waste classification and collection system can be roughly divided into three categories: household classification and recycling system, group recycling system and manufacturer, and circulation field recycling and reuse system. Garbage is sorted at home, collected by the local government, or recycled by groups and sales stores, and finally sent to sorting facilities for processing before being sent to various recycling facilities for reuse. This situation is related to the country's incineration of waste and the level of resource waste reuse. The finer the front-end classification work, the easier the back-end resource utilization work will be, which can reduce the difficulty of mechanical sorting. In order to facilitate processing and utilization, Japan has installed equipment such as bottle and jar sorting machines, magnetic separators, and glass crushers in some cities' waste resource recycling centers. In summary, in Japan, systematic theory has been fully applied and reflected in the process of waste management. Due to a series of measures such as garbage classification, the total amount of garbage in Japan has remained relatively stable since 1988, without significant growth, while the amount of garbage in cities such as Tokyo has even decreased. Figure 3-5 shows the schedule for garbage disposal in Japan.
The garbage pipeline collection system is a relatively advanced garbage collection method in the world today, which has been applied to cities in many countries around the world [13]. The application of garbage pipeline collection technology in Asia is mainly concentrated in Japan and Singapore, and it is also applied in Hong Kong, China. The process flowchart of this technology is shown in Figure 3-6. Currently, Japan mainly uses Mitsubishi's pipeline collection system to directly transport waste from the surrounding areas of incineration plants, such as Tokyo Bay and Yokohama.
