Japan waste disposal method draws attention in Africa as way to curb global warming

SHARM EL-SHEIKH, Egypt (Mainichi) -- The issue of waste in Africa was discussed extensively at the COP27 climate change summit here. Expectations are high for waste treatment technology from Japan, but how are global warming and waste processing related?

In Africa, it is estimated that less than 10% of all waste is currently being properly disposed of at controlled landfill sites or through recycling. In many cases, waste is just piled up in naturally formed dumping areas, and these sites are drawing attention as a source of methane.

Methane is a potent greenhouse gas, and an international framework aiming for a 30% reduction of the gas from 2020 levels by 2030 was established at the COP26 summit in 2021. About 20% of the world's methane emissions come from waste, and during the 27th Conference of the Parties (COP27) to the United Nations Framework Convention on Climate Change, the host country, Egypt, proposed a framework aimed at reducing methane, with the goal of properly disposing of at least 50% of Africa's waste by 2050.

To contribute to this initiative, the Japanese government promoted landfill technology called the "Fukuoka method" as a measure to reduce methane emissions.

When food scraps are piled up in fields, filthy water accumulates inside, causing a lack of oxygen, and methane is generated by microorganisms that are active in such an environment.

The method, developed by Fukuoka University and the Fukuoka Municipal Government, is a technology in which drainage pipes and gas venting pipes are installed to drain water and allow air to flow naturally into the stacked layers of waste, thereby suppressing methane generation. It has been introduced in many parts of Japan, and in 1979 it was adopted as the standard structure in the country under national guidelines for final landfill sites.

The advantage of the Fukuoka method is that it can be implemented with materials that are easily available in developing countries, such as bamboo and scrap tires. According to the Fukuoka government, the method has already been adopted in 21 countries around the world including in Asia, Latin America and Africa, with technical cooperation from the Japan International Cooperation Agency (JICA) and other organizations.

Yasushi Matsufuji, professor emeritus at Fukuoka University, who was involved in the development of the method, told the Mainichi Shimbun, "It is important to use materials that can be obtained locally and to convey technologies that local people can master. The waste problem in developing countries is not only environmental, but also encompasses poverty, industry, and many other issues."

Matsufuji has been supporting waste management in Africa and elsewhere as a representative of a nonprofit organization.

"Sharing the technology should help improve the livelihood of Africa as a whole," he said.

(Japanese original by Tomoko Mimata and Ei Okada, Science & Environment News Department)