CO2 reconversion into fuel, building materials under development

The Yomiuri Shimbun
A demonstration of methanation equipment is seen at the Osaka Gas Energy Technology Laboratories in Konohana Ward, Osaka City.

Energy giants and other companies are stepping up the development of technologies to recycle carbon dioxide to produce city gas, construction materials, chemicals and other products.

If the companies can put to practical use the recycling of CO2 — a gas emitted in large quantities in power generation and other industrial activities — their business chances will increase. Thus, competition is intensifying to lower costs and realize mass applications of such processes.

Seeing CO2 as a resource

Osaka Gas Co. has been developing a technology called methanation that synthesizes CO2 and hydrogen to produce methane, the main component of city gas. CO2 will indeed be generated when city gas is burning, but that CO2 will be reused to produce city gas again, so CO2 emissions will be effectively zero, the company said.

The company has been running TV ads since April in which a narrator reads, “Everyone wants to reduce CO2, but it looked like a resource to us.”

Although there are no examples of putting CO2 recycling into practical use yet, the basic technology has been established. Osaka Gas is developing its own technology to reduce the electricity needed for methanation production and plans to replace 1% of its city gas supply with the recycled gas by 2030 and 90% by 2050.

“It must lead to significant greenhouse gas reductions in the future,” said Hisao Onishi at the Osaka Gas Energy Technology Laboratories.

Heavy machinery manufacturer Hitachi Zosen Corp. is strong in catalyst technologies — essential for the reaction of CO2 and hydrogen — and has been developing methanation technology since 1995. The company also sells methanation equipment for tests. It recently delivered methanation equipment to Tokyo Gas Co.

In May, Hitachi Zosen began test operations of methanation equipment at a waste incineration plant in Odawara, Kanagawa Prefecture. The equipment captures the CO2 emitted during incineration for the purpose of methanation — the first such use of methanation equipment at a waste incineration facility.

Competition may intensify

The government has set a goal of net-zero emissions of greenhouse gases including CO2 by 2050. As one of the technologies to achieve this goal, it will push for the capture and conversion of CO2 into a resource, called carbon recycling.

The Economy, Trade and Industry Ministry said that the technology to produce various materials from CO2, including plastics, jet fuel, minerals and concrete, will be commercially available by around 2030.

Electric power giants are also focusing on developing the reuse of CO2, as they emit large amounts of it.

Chugoku Electric Power Co. is trying to produce sand with good drainage properties using CO2. The sand is produced by exposing the mixture — CO2, concrete pieces from crushed unused utility poles and coal ash from thermal power generation — to microwaves. The sand is intended for use on playgrounds and other places.

Kansai Electric Power Co. has begun research on microalgae that produce a special substance from CO2. The substance has an ingredient applicable to therapeutic agents for arteriosclerosis.

Among major chemical companies, Asahi Kasei Corp. and Mitsubishi Chemical Corp. are developing technologies to mass-produce raw materials for urethane resins and plastics from CO2.

Research firm Fuji Keizai Co. estimates that the market for CO2 separation and carbon recycling will grow 17.2% from ¥4.857 trillion in 2019 to ¥5.693 trillion by 2030.