Asahi Kasei Unveils Biogas Purification System at Kurashiki Sewage Treatment Plant
Asahi Kasei and Kurashiki City celebrated the grand opening of a groundbreaking biogas purification system at the Kojima Sewage Treatment Plant in Kurashiki, Okayama Prefecture, Japan. This system utilizes Asahi Kasei’s innovative CO2 separation and recovery technology, specifically leveraging zeolites to efficiently purify biogas. This collaboration aims to evaluate and demonstrate the performance of the system, marking a significant step in the quest for carbon neutrality.
A Step Toward Carbon Neutrality
This new project is a product of the partnership between Asahi Kasei and Kurashiki City, formalized through a comprehensive agreement signed on September 15, 2022. The partnership focuses on advancing decarbonization efforts and achieving carbon neutrality, aligning with global sustainability goals. The demonstration trial of the biogas purification system is a crucial component of this initiative, which will help evaluate the potential of the technology for wider adoption in future energy applications.
Asahi Kasei’s commitment to sustainability is reflected in this technology, as the company actively works toward reducing the environmental impact of energy production and consumption. The biogas purification system is one of the many steps being taken to reduce carbon emissions in Japan and abroad, contributing to global decarbonization goals.
The Technology Behind the Biogas Purification System
The system implemented at the Kojima Sewage Treatment Plant utilizes Asahi Kasei’s advanced CO2 separation technology, which employs a combination of a specialized zeolite as an adsorbent and a unique pressure vacuum swing adsorption (PVSA) process. The zeolite is a crystalline aluminosilicate material that possesses regular channels and cavities, enabling it to selectively adsorb CO2. This allows for the efficient separation of CO2 from biogas, refining high-purity methane gas (biomethane) at a high recovery rate.
The PVSA process is key to the system’s success. It uses pressure changes to separate specific gases, making it ideal for isolating CO2 from the biogas mixture. This method is highly efficient, with a high recovery rate of methane, making it a valuable tool for biogas purification. The separation process results in the production of biomethane, a carbon-neutral fuel that is considered a sustainable substitute for natural gas.
Biogas typically consists of approximately 60% methane and 40% CO2. While biogas has been recognized as a potential renewable energy source, the separation of CO2 is crucial to refining the biogas into usable biomethane. This purification process helps to increase the quality and purity of the methane, which can then be used for power generation, heating, or other energy needs.
Utilizing Biogas for Sustainable Energy Production
At the Kojima Sewage Treatment Plant, biogas is generated from sewage sludge and used to produce electricity. The new biogas purification system will process a portion of this biogas during the demonstration trial. The goal is to demonstrate the viability of biogas purification and recovery as a renewable energy source that can be effectively integrated into existing energy production systems.
One of the exciting aspects of this system is its potential for carbon capture, utilization, and storage (CCUS). In the demonstration trial, the CO2 separated by the system could be utilized or stored, resulting in a carbon-negative process. This is a major advancement in carbon capture technology and offers significant potential for reducing the carbon footprint of industrial processes.
Additionally, the purified methane produced during the process will be returned to the system and used as fuel for generating electricity, further enhancing the sustainability of the biogas utilization process. By refining the biogas into high-purity biomethane, the system contributes to the efficient use of renewable energy and the reduction of greenhouse gas emissions.
Collaboration and Global Expansion Plans
The demonstration trial of the biogas purification system began in February 2025, with Asahi Kasei responsible for the design, installation, and operation of the system. The company is also tasked with evaluating the performance of the system throughout the trial period. Kurashiki City plays a vital role in supplying the biogas derived from sewage sludge and providing the site for the trial.
This collaboration between Asahi Kasei and Kurashiki City is an excellent example of the public-private partnerships needed to drive sustainable innovation. It demonstrates the critical role of local governments in supporting green technologies and promoting environmental stewardship.
Looking ahead, Asahi Kasei plans to commercialize the biogas purification system by around 2027. Before this, additional trials will be conducted in regions where biogas purification is already underway. These trials will help to further refine the system and assess its scalability, making it ready for global deployment.
A Global Vision for Sustainability
Asahi Kasei’s ultimate goal is to expand the use of its biogas purification system globally. By forming partnerships with other countries and regions involved in biogas production, the company aims to accelerate the development and adoption of this technology worldwide. The company is actively working to establish co-creation partnerships with key players in the biogas and energy industries to facilitate the global implementation of this technology.
Osamu Matsuzaki, Senior Executive Officer of Asahi Kasei and Senior General Manager of Corporate Research & Development, shared his enthusiasm for the project: “We are excited to start the on-site demonstration trial of a biogas purification system using Asahi Kasei’s zeolite and PVSA process technology. As the next step, by expanding co-creation partnerships globally, we will accelerate the advancement and practical implementation of this outstanding technology that can reduce environmental impacts, contributing to sustainability for the world.”
Through global partnerships, Asahi Kasei hopes to play a leading role in the development of a circular economy, where waste and byproducts are utilized as resources to create sustainable energy. The biogas purification system is a key component of this vision, demonstrating the potential for renewable energy solutions to contribute to a more sustainable future.
Conclusion
The grand opening of the biogas purification system at the Kojima Sewage Treatment Plant marks a significant milestone in the journey toward a more sustainable and carbon-neutral future. Through innovative technology and strategic partnerships, Asahi Kasei is helping to pave the way for the global adoption of renewable energy solutions. With continued collaboration and research, the company is poised to make a meaningful impact in the global effort to reduce greenhouse gas emissions and mitigate climate change. Asahi Kasei’s commitment to sustainability and carbon neutrality is evident in this groundbreaking project, and it serves as a model for future innovations in the field of clean energy.
