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Tokyo, October 16, 2025 – Mitsubishi Heavy Industries Environmental & Chemical Engineering Co., Ltd. (MHIEC), a part of Mitsubishi Heavy Industries (MHI) Group, has received a contract from the city of Kanazawa (Ishikawa Prefecture) to refurbish and improve the core facilities of the city’s East Environmental Energy Center, a municipal solid waste (MSW) incineration plant. The renovation of the stoker-type incinerators(Note1) with processing capacity of 250 tons per day (tpd) aims to extend the life of the facility, enhance energy efficiency, and reduce CO₂ emissions. The total value of the contract is 4.3 billion yen before tax, with work scheduled to be completed in March 2029.

The East Environmental Energy Center was engineered and built by MHI, and completed in March 1991. It comprises two stoker-type incinerators, each with processing capacity of 125 tpd. Power generation capacity utilizing residual heat from the plant is 3,000 kilowatts (kW).

The plant’s core facilities have previously been refurbished twice, first over a four-year period from 2004, followed by a round of construction over a four-year period from 2014. This third refurbishment aims to extend the operational life of the facility through renewal of major equipment that has become impossible to maintain due to deterioration over time and production discontinuation, including the facilities for waste reception and feeding, combustion, combustion gas cooling, exhaust gas treatment, and waste heat utilization. In addition, energy efficiency will be enhanced with the adoption of high-efficiency motors and transformers, while upgrades to MHIEC’s proprietary new combustion control system, previously installed as part of the earlier improvement work, will allow for a lower air ratio(Note2) and provide more stable combustion.

In recent years, the number of renovation projects for MSW facilities has increased as a measure to extend the operational life of such plants, and reduce their impact on global warming. MHIEC took over the waste treatment plant business in 2008, acquiring MHI’s technological development capabilities in environmental systems and broad-ranging expertise in the construction and operation of waste management facilities both in Japan and overseas. This extensive experience allows MHIEC to provide comprehensive solutions, from plant construction to operations. Going forward, leveraging this latest order and its past results, MHIEC will proactively propose further energy-saving enhancements and system improvements for stable operation at existing waste treatment facilities, as well as ways to reduce lifecycle costs, including maintenance and management costs, leading to further business contracts.

• 1 A stoker-type incinerator injects air from beneath heat-resistant fire grates, mixing the waste and other material by pushing it up, and allowing for efficient incineration. It is the most common system used for municipal solid waste (MSW).
• 2 The air ratio is the value of the actual amount of air supplied to the incinerator for combustion, divided by the theoretical minimum amount of air required for complete waste combustion.