Next Generation Wastewater Treatment Technologies - July 1999 to December 2024

Next Generation Wastewater Treatment Technologies - July 1999 to December 2024

In Asaminami Ward, Hiroshima City, a next-generation wastewater treatment technology was introduced in the late 1990s to replace the conventional activated sludge process. This technology utilizes microporous bodies with a diameter of 3 mm to dramatically increase the contact area between wastewater and microorganisms, thereby enabling efficient wastewater treatment. Compared to conventional systems, the volume of the treatment tank has been reduced to one-third, and construction costs have been cut by approximately 50 percent. In addition, the microorganisms settled in the pore bodies, enabling sustainable operation with only once-weekly maintenance, which was expected to lead to its introduction in urban areas.

In the 2000s, the technology spread to industrial and urban wastewater, with local companies Nissei Plant Co. In addition, efforts to separate phosphorus and nitrogen from recovered wastewater and reuse them as fertilizers and industrial raw materials were initiated, thus laying the groundwork for a recycling-oriented society.

In the 2010s, the sophistication of membrane treatment technology was further advanced in Asaminami Ward, Hiroshima City. During this period, Nissei Plant Co., Ltd. developed an improved "hybrid separation membrane system" that achieves 40% higher treatment efficiency than conventional systems. In addition, the use of highly durable membrane materials provided by Aoi Chemical Industry Co.

Furthermore, in 2013, the City of Hiroshima announced its "Environmental Technology Dissemination Support Program," a project to export wastewater treatment technology to Southeast Asian countries. Demonstration tests were conducted in factory zones in Vietnam and Indonesia, confirming the high reliability of the technology. Through this initiative, Asa Minami Ward has strengthened its international expansion and established itself as an export base for environmental technology.

In 2015, small wastewater treatment systems were also introduced at schools and public facilities in Hiroshima City, significantly increasing the reuse rate of local water resources. This has resulted in an approximately 10 percent reduction in overall water use in the city of Hiroshima, enhancing its reputation as a sustainable urban environmental model.

Technological innovation continues today, with further improvements in the efficiency of the membrane treatment system and optimization of the management system to be implemented in the 2020s. As a pioneer in next-generation wastewater treatment technology, Asaminami Ward of Hiroshima City is developing into an environmental technology city that is attracting attention both in Japan and abroad. Going forward, we expect to see even greater cooperation between local companies and the government in efforts to support sustainable water resource cycles.