Part 2 CCT Overview
Multi-purpose Coal Utilization Technologies (Powdering, Fluidization, and Co-utilization Technologies)

4C4. Coal and Woody Biomass Co-firing Technology
Research and development: New Energy and Industrial Technology Development Organization;
Chugoku Electric Power Co., Inc.; Hitachi, Ltd.; Babcock-Hitachi K.K.
Project type: High-efficiency biomass energy conversion technology development
Period: 2001-2003 (3 years)

Technology overview

1. BackgroundAs part of their global warming countermeasures, industriallyco-firing options. One is to simply pulverize the woody biomass inadvanced countries are implementing policies to promote theexisting mills and combust the pulverized coal-biomass mixture

adoption of power generation using renewable energy. One offuel in a boiler, using the existing burner. This method requires

these is the Renewable Portfolio Standard (RPS) system. The

fewer equipment modifications and therefore costs less. However,"Special Measures Law concerning the Use of New Energy by

mixtures of more than several percent of biomass cause the mill’sElectric Utilities" (RPS Law) was enacted in April 2003, andpower consumption to sharply increase due to the difficulty ofobligates electric utilities to obtain a specified amount of theirgrinding woody biomass with ordinary pulverizers. The otherenergy from new energy power generation sources. The portion

option is to establish a biomass-dedicated mill. Despite the higherof energy derived from alternative sources is expected toequipment costs, this method is advantageous not only because

increase from 3.3GkWh in 2003 to 12.2GkWh in 2010. Included

a higher ratio of biomass can be utilized but also because thein the definition of new energy is biomass fuel.

amount of NOx generated can be reduced.

The co-firing of coal and woody biomass in the power generation

Technology development of the latter option, commissioned bysector, though already underway in the U.S. and European

the New Energy and Industrial Technology Development

countries, is new to Japan and is facing a variety of technologicalOrganization (NEDO), is underway.

problems. For pulverized coal-fired boilers, there are roughly twoCombustion test/evaluation

Woody biomass
technology investigation
BoilerFlue gastreatment

MillCoalBurner
Woody biomass

Separation Storage DryingCrushing

FS for commercialization

Pre-treatment technology
development

Fig. 1 Process flow of coal/woody biomass co-firing system

73Clean Coal Technologies in Japan

2. Development target

3. Technologies to be developed(1) Co-firing ratio of woody biomass: 5-10%(1) Woody biomass pre-treatment technology (mainly grinding)(2) Clearance of current regulatory environmental restrictions(2) Woody biomass combustion technology (co-firing burner/biomass-(3) Power generation efficiency comparable to that of existing

dedicated burner)coal thermal power plants: A decrease in net thermal efficiency ofless than 0.5% with a woody biomass co-firing ratio of 5% (on acalorific base).
Bagfilter
BurnerMill [1]To stacks

BinBiomass

Furnace

HopperFeederHopperCycloneFeederHeaterCrusher

BlowerDrier

Mill [2]Fig. 2 Process flow of pilot-scale test facility

4. Development progress and results
This project, was conducted at Chugoku Electric Power Co., Inc.,

NEDO, for the evaluation of the pilot plant’s combustion results,

Hitachi, Ltd., and Babcock Hitachi K.K., and commissioned bywith an eye toward commercialization.

R&D timetable20012002

20032004

2005

Coal/woody biomass co-firing technology R&D (commissioned by NEDO)

Demonstration test

Development of component technologies for processes from receiving to storage,
crushing, dry-boiler combustion, and flue gas/ash disposal

Component technology development results-based
deployment toward demonstration tests

1. Woody-biomass technology investigation
2. Pre-treatment technology development

Planning

3. Combustion test and evaluation

Installation work

4. FS for commercialization

Demonstration test

Review of forest biomass utilization by local governments
Utilization planning and system design/verification

Supply system and other improvements/developments

References

1) Kazuhiro Mae: Coal Utilization Technology Information Journal No. 253, pp. 3-5, Feb. 2002.
2) Hiroshi Yuasa: A collection of lectures from Thermal/Nuclear Power Generation Convention, Fukuoka, pp. 102-103, Oct. 2003.

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