Expansion of Waste Plastic Incineration - Waste Policy, Social Background and Related Technologies before and after 2007 (November 2007)

Expansion of Waste Plastic Incineration - Waste Policy, Social Background and Related Technologies before and after 2007 (November 2007)

In Japan in the mid-2000s, there was a major shift in policy regarding the treatment of waste plastics. Traditionally, plastic waste was disposed of in landfills as "noncombustible waste" by many municipalities because of the high temperatures required for combustion and the high risk of dioxin generation. However, the situation changed drastically when large-scale renovation of incinerators progressed and high-efficiency furnaces that could meet dioxin regulations became widely used, while final disposal sites became increasingly tight.

According to a survey conducted in 2007, about 70% of the 50 cities in Japan had switched to incineration of waste plastics as "combustible waste," and this number was rapidly growing. In the background was a shortage of landfill space and advances in incineration technology. Stoker furnaces and fluidized bed furnaces achieved complete combustion with staged air supply and high-temperature secondary combustion chambers, while fabric filters and activated carbon adsorption efficiently removed dioxins and mercury. As a result, plastics, once considered dangerous, were deemed safe to dispose of.

Furthermore, the combination of a high-temperature, high-pressure boiler and extraction condensate turbine has improved power generation efficiency, and the use of latent heat and cold heat from an exhaust gas condenser and absorption refrigerator has increased overall efficiency. As for chlorine-based plastics such as PVC, corrosion and dioxin resynthesis were suppressed by adopting corrosion-resistant materials and optimizing combustion conditions.

The Containers and Packaging Recycling Law has expanded the practical response to the problem of waste plastics that are difficult to recycle, while continuing material recycling of PET and other plastics, and allocating waste plastics that are difficult to recycle to thermal recovery. In addition, alternative routes such as RPF (solid fuel) and cement kiln use coexisted, and a treatment system linked to local industries was sought.

Ultimately, the expansion of waste plastic incineration was positioned as an integrated solution that simultaneously achieved landfill life extension, energy recovery, and compliance with environmental regulations, and became the technical and institutional foundation that supported Japan's transition to a recycling-oriented society.