Kawasaki Develops Forty-percent-hydrogen Mixed-fuel Technology in Gas Turbine DLE Combustors

Dec. 07, 2021

December 7, 2021 — Kawasaki Heavy Industries, Ltd. (Kawasaki) announced today Hydrogen mixed-fuel combustion technology up to 40 percent in gas turbine DLE combustors*1 that enables stable combustion with low NOx*2 emissions has been developed. This advanced technology can be adapted for use with existing DLE combustors in operating Kawasaki gas turbine generators, encouraging effective utilization of existing facilities. Kawasaki is confident to significantly contribute toward achieving a future carbon-neutral society through practical applications of hydrogen energy.

Hydrogen has a faster combustion speed and higher combustion temperature than natural gas, leading to technical challenges such as a significant increase of NOx emissions and overheating of the burners when it is used in lean-premixed combustion*3. In response to these issues, with its know-how of hydrogen combustion, Kawasaki developed a system that properly controls fuel ratios for lean-premixed combustion and supplemental combustion*4 to mitigate NOx emissions and realize stable, mixed-fuel combustion using hydrogen.

Kawasaki utilizes an original and unique combination of lean-premixed combustion and supplemental combustion. In the lean-premixed combustion, fuel is mixed with air prior to combustion in order to eliminate localized high-temperature spots where the most of NOx emissions are produced. Supplemental combustion injects fuel after lean-premixed combustion, and stably increases the power output with no increase of NOx emissions. The use of the two combustion technologies together enables the NOx emissions to be kept below 15 ppm (converted at 15% O2) at a wide range of power output.
By successfully applying this proprietary combustion technologies to hydrogen-mixed fuel combustion as well, Kawasaki has realized a stable combustion while maintaining low NOx emissions on a par with those of natural gas combustion. Furthermore, the company has also a means of adapting existing systems for hydrogen-mixed fuel combustion with only a modification of auxiliary system for existing gas turbines, thus preserving the reliability of proven Kawasaki gas turbine generation system.

Kawasaki is currently pursuing development and commercialization of three types of hydrogen- compatible gas turbine combustors*5. The latest development relates to combustor type (2) below, which will play an important role in promoting hydrogen-based energy usage.

With an eye to the popularization of hydrogen energy, which will play a vital role in the future achievement of a zero-carbon-emission society, Kawasaki is developing a range of different products that serve variously in the production, transportation, storage and utilization scenes of the hydrogen supply chain. Among these, hydrogen gas turbines are vital utilization products that will make significant contributions toward the elimination of carbon emissions in Japan’s power generation industry, which accounts for roughly 40 percent of the nation’s CO2 emissions. Moving forward, Kawasaki will continue to develop gas turbine combustion technologies that enable utilization of hydrogen, working as one for the good of the planet.

*1    A method of mitigating NOx emission volumes by keeping combustion temperatures low without relying on water and steam injection.
*2    Nitrogen oxides. A category of oxides formed through the joining of nitrogen and oxygen in the air as a result of high-temperature combustion. NOx are causal factors in photochemical smog and acid rain. Emission amounts for NOx are limited by the Air Pollution Control Act and local-government ordinances.
*3    A method of combustion in which fuel is evenly mixed with air prior to combustion and the lean mixture is injected into the combustor. This method greatly reduces NOx emissions by achieving a uniform temperature distribution without local high-temperature spots.
*4    A method of combustion in which fuel is injected downstream of lean pre-mixed combustion. This method can be used to change output levels while maintaining stable lean pre-mixed combustion by adjusting supplemental fuel, and enables NOx emissions to be kept low.
*5    For more information, refer to Kawasaki’s hydrogen gas turbine development roadmap:



If you need more information about our business,
please feel free to contact us.