Part 2 CCT Overview
Coal-fired Power Generation Technologies (Combustion Technologies)

2A6. Pressurized Fluidized-bed Combustion Technology (PFBC)
Research and development: Japan Coal Energy Center; and J-POWER
Project type: Coal Production and Utilization Technology Promotion Grant
Period: 1989-1999 (11 years)

Technology Overview

1. Background and process overview(1) The research and development of pressurized fluidized-bed(2) Overview of facilities

combined power generation technology was conducted atPlant output 71.0 MWe

J-POWER’s Wakamatsu Coal Utilization Research Center (nowPressurized fluidized-bed combustion boiler (ABB-IHI production)

known as Wakamatsu Research Institute) using a 71 MWe-PFBC

Bubbling-type pressurized fluidized-bed, coal water paste

Plant, the first PFBC plant in Japan. The test plant was the first(70-75%) injection-type

plant in the world to adopt a full-scale ceramic tube filter (CTF)

Combustion temperature: 860oC

capable of collecting dust from high-temperature, high-pressure

Combustion air pressure: 1 MPa

gas at a high-performance level. An overview of the process isshown in Figure 1.

Ammonia water injection(Non-catalytic denitration)
Ash recirculationcyclone

Ceramic tube filter(CTF)

Main steam/Reheated steam
593 C/593 C
Steam turbine
OOAir
Gas turbine

CTF ashFuelnozzle

Intercooler

Condenser

Coal,limestone,
water

Denitration
unit

Pressurevessel
Bottom ash (BM)Deaerator

Water
supplypump

Fuel slurry pumpWater
supplyheaterEconomizer

Fig. 1 Flowchart of PFBC process31Clean Coal Technologies in Japan

2. Development objective and technology to be developed
PFBC technology development objectives:

elimination of the desulfurization unit.

(1) Increase efficiency through combined power generation

Results of PFBC technology development:utilizing pressurized fluidized-bed combustion with a gross(1) Gross efficiency of 43% was achieved by increasing efficiency

efficiency of 43%.

through combined power generation utilizing pressurized(2) Providing advanced environmental features, including:

fluidized-bed combustion.

SOx reduction through in-bed desulfurization; NOx reduction(2) SOx level of approximately 5 ppm through in-bed desulfurization;

through low-temperature combustion (approximately 860oC); Dust

NOx level of approximately 100 ppm through low-temperature

reduction by CTF; and CO2 reduction through increased

combustion (approximately 860oC), and dust of less than 1

efficiency.

mg/Nm3 by CTF.

(3) Space-savings through a compact pressurized boiler and the3. Progress and development results
Detailed design of the facilities began in FY1990 and1997. After that, the plant was modified to adopt the ash-recycling

construction began in April 1992, with equipment installation

system. Phase 2 of the demonstrative operation was conductedcommencing in October 1992. Test operations began in April

from August 1998 to December 1999. The cumulative operating

1993, while coal combustion was commenced in September

time of the PFBC system was 16,137 hours, including 10,981

1993, and 100% load capacity was achieved in January of 1994.

hours in phase 1 and 5,156 hours in phase 2. In phase 2, theThe two-stage cyclone system passed inspections before

system was operated continuously for 1,508 hours. Through theentering operations in September 1994, and the CTF passed

operation, valuable data and findings were made in terms ofinspections before entering operations in December 1994. Phase

performance and reliability. Three electric power companies have

1 of the demonstration operation was conducted until December

already applied these results during the construction ofcommercial facilities.

PFBC development schedule
FY1990

FY1991

FY1992

FY1993

FY1994

FY1995

FY1996

FY1997

FY1998FY1999Final assessment

FY1989Interim assessment

Fiscal year
Item

Basic and detailed design
Construction begins Integration
Construction of demonstration plant
Test operation and adjustments
Demonstration operation phase 1

Test operation
Modification

Modification

Demonstration operation phase 2

Test operation

4. Issues and feasibility of practical application
Due to its environment-friendly characteristics, including SOxmaterials and waste by utilizing the technology’s superior

emissions of 10ppm or less, NOx emissions of 10 ppm, and dust

combustion performance; the in-bed desulfurization; theconcentration of 1mg/Nm3 or less, and also due to the space-combination of catalytic or non-catalytic denitration; and the high-savings brought about by the elimination of the desulfurization

temperature and high-performance dust collection from the CTF.

unit, the PFBC system is highly suitable for urban-operation.

An outstanding issue is improving the cost-efficiency by fully

These advantages are obtained by: the flexibility to utilize aleveraging these characteristics of the system and by selecting avariety of fuels, such as difficult-to-combust or low-grade

proper location.

Reference

Yamada et al., "Coal Combustion Power Generation Technology," Bulletin of the Japan Institute of Energy, Vol. 82, No. 11, pp. 822-829, November 2003.

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