Press ReleasesNippon Paper Industries Develops New Biomass Solid Fuel Effective for Reducing CO2 Emissions
Biomass Co-Firing Rate in Existing Coal Fired Boiler Rises
by an Approximate Factor of Ten- Confirms mixture of 25% in co-firing experiment with a pulverized coal boiler under the NEDO
project adopted for fiscal 2011 -
Nippon Paper Industries Co., Ltd.
Nippon Paper Industries Co., Ltd. (President; Yoshio Haga) is pleased to announce that it has developed new biomass solid fuel using torrefaction technology (Note 1) under the project of the New Energy and Industrial Technology Development Organization ("NEDO") adopted for fiscal 2011. The experiments of co-firing were conducted on a pulverized coal boiler at the Yatsushiro Mill (Yatsushiro, Kumamotro) of Nippon Paper Industries and as a result, 25% (as weight ratio) of new biomass solid fuel could be incorporated under the maximum load of the boiler. The experiments confirmed that there are no problems with the runnability of a coal pulverizing facility and the combustibility of a boiler.
In Japan, the rate of dependence to coal-fired power generation is increasing under the influence of the Great East Japan Earthquake, and reduction of the greenhouse gas (CO2) amount of emergence which is increasing in connection with it has been a subject. Recently, pulverized coal boilers with enhanced combustion efficiency are being used principally as coal fired boilers. Companies including Nippon Paper Industries are promoting the co-firing of woody biomass fuel such as wood chips and wood pellets to reduce CO2 emissions. However, the co-firing rate for these fuels in a pulverized coal boiler has remained about 2% to 3% because they cannot be pulverized efficiently and also because of their water resistance when storing them outside, among other problems.
New biomass solid fuel developed by Nippon Paper Industries recently under the project of NEDO can retain about 90% of its heat quantity by using technology to semi-carbonize woody biomass (torrefaction), compared with about less than 50% for normal carbonization. In addition, new biomass solid fuel may enhance the crushability and water resistance and significantly improve the co-firing rate of biomass in a pulverized coal boiler.
Nippon Paper Industries, as a comprehensive biomass company promoting the comprehensive use of wood, will further pursue the improvement and demonstration of the manufacturing process for new biomass solid fuel and will continue developments to provide next-generation biomass fuel with higher efficiency.
Also known as semi-carbonization, torrefaction is a technology similar to the roasting of coffee beans.
Carbonization of woody biomass at a relatively low temperature retains more heat quantity than normal carbonization does. In addition, wood pellets have less volume compared with wood chip fuel, leading to an improvement in transportation efficiency and etc.
In fuel manufacturing using torrefaction technology, it is necessary to carefully control the processing temperature and there are other requirements. Consequently, the establishment of the technology for practical application had been an issue that needed to be resolved.
- Note2:Pulverized coal boiler:
Coal fire power boilers in recent years have pulverized coal boilers in use which makes coal pulverized in order to improve combustor efficiency and makes it blow off in a boiler, and it burns. In order to be co-fired together with the woody biomass fuel, it is necessary to make it pulverized the same as coal.