Hokubu Waste-to-Energy Plant
TOKYO, Apr 22, 2026 - (JCN Newswire) - Mitsubishi Heavy Industries Environmental & Chemical Engineering Co., Ltd. (MHIEC), a part of Mitsubishi Heavy Industries (MHI) Group, has recently completed the improvement of core equipment for Hokubu Waste-to-Energy Plant, a municipal solid waste incineration facility in Kagoshima City. The work consisted of renovation of the stoker type incinerators, capable of processing 530 tonnes per day (tpd) (1), to extend the plant's service life and reduce CO2 emissions. This was a project spanning a six-year period from fiscal 2020 to fiscal 2025.
The Hokubu Waste-to-Energy Plant was originally designed and constructed by MHI, and completed in March 2007. It comprises two units of stoker type incinerators, each with processing capacity of 265 tpd, plus related equipment, delivering power generation capacity of 8,700 kW.
Under the refurbishment work, upgrades have been made to deteriorated major equipment, to achieve stable combustion and operation over the long term. Additionally, a low-temperature catalyst, a proprietary technology of MHIEC, was introduced to the SCR (Selective Catalytic NOx Reduction) system to improve the heat recovery rate (2), a low excess air ratio incineration technology (3) was adopted to improve combustion and the efficiency of the boiler, and the output of the steam turbines was increased from 8,700 kW to 10,005 kW, which will reduce CO2 emissions by approximately 33.1% per year.
MHIEC took over MHI's waste treatment plant business in 2008, acquiring the technological development capabilities in environmental systems and broad-ranging expertise in the construction and operation of waste management facilities both in Japan and overseas that MHI honed over many years. A strength of this company is its ability to propose total solutions from construction to operation based on its extensive track record. Going forward, MHIEC will continue to proactively make proposals to extend the life of existing waste treatment facilities, take measures against global warming, and reduce lifecycle costs (LCC) such as maintenance and management costs to contribute to the decarbonization of energy through the collection of energy from waste.
(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.
(2) An SCR system removes nitrous oxides (NOx), an air pollutant in exhaust gases, and typically operates at a high temperature. With MHIEC's technology, a catalyst that can remove NOx at low temperatures was introduced to the SCR system, eliminating the need to heat the exhaust gas to a high temperature and increasing the heat recovery rate.
(3) The volume of air required for combustion is suitably distributed to reduce the volumes of combusted air and exhaust gas, increasing the efficiency of the boiler and decreasing the energy consumption of the induced draft fan.
About MHI Group
Mitsubishi Heavy Industries (MHI) Group is one of the world’s leading industrial groups, spanning energy, smart infrastructure, industrial machinery, aerospace and defense. MHI Group combines cutting-edge technology with deep experience to deliver innovative, integrated solutions that help to realize a carbon neutral world, improve the quality of life and ensure a safer world. For more information, please visit www.mhi.com or follow our insights and stories on spectra.mhi.com