Part 2 CCT Overview
Multi-purpose Coal Utilization Technologies (De-ashing and Reforming Technologies)

4D1. Hyper-coal-based High-efficiency Combustion Technology (Hyper-coal)
Research and development: Japan Coal Energy Center; National Institute of Advanced
Industrial Science and Technology; and Kobe Steel, Ltd.
Project type: Development and Survey of Next Generation Technology for Coal Utilization, promoted by New Energyand Industrial Technology Development Organization (NEDO)
Period: 2002-2007 (6 years)

Technology overview

1. Background and objectives
Because of abundant coal reserves, the expectations of a stablecombined-cycle power generation systems (a combination of gas

supply, and low cost, the demand for coal is expected to increase.

turbines and steam turbines) achieves more efficient power

The emission of CO2 and other substances during thegeneration than existing pulverized coal-fired power generation. If

combustion of coal, however, has a more significant impact on

impurities such as ash and alkali metals can be removed from coal,

the environment than does the use of other fossil fuels.

the clean coal can be used as fuel to be directly combusted in gas

Given this, it is essential to decrease CO2 emissions from coal-turbines.

fired power plants, which account for a large percentage of theNEDO is promoting the development of combined power generationcoal consumed. To do so, new power generation technology withtechnology, where coal treated by solvent extraction and ion

higher thermal efficiency must be developed and disseminatedexchange processes to remove the ash and alkali metals to obtainworldwide.

clean coal (Hyper-coal), can be directly combusted in gas turbines.

If coal is directly utilized as a gas turbine fuel, the adoption of2. What is Hyper-coal?
A solvent with a high affinity to coal is applied during the ash

Once the solvent is removed from the solution, the final product,extraction process. Ash present in the coal is removed from theHyper-coal, has little ash content.

solution though the use of a solid-liquid separation technology.
CharcoalHyper-coalSolvent

Coal

Solvent penetrates coal.

Cohesiveness of coal breaks down,
and soluble portions are dissolved.

Insoluble portions and ash areremoved as sediment.

Residue coalFig. 1 Conceptual drawing of Hyper-coal manufacturing from coal

3. Hyper-coal production facilities(1) Heating-extraction unit

(2) Solid-liquid separation unit

Coal is first treated with a solvent, and then thePictured in Photo 2 is a settler with the ability tosolution is treated by a high-temperature

separate coal from the sediment, (designfiltration process to remove residue, thus

temperature: 500oC, design pressure: 5 MPa).

producing Hyper-coal. (Design temperature:

Five vertically arranged valves collect samples

500oC, design pressure: 3MPa) This unit canto determine the sedimenting state of un-

produce various grades of Hyper-coal samples.

dissolved matter under pressurized and heatedconditions.

Photo 1 Heating-extraction unit

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Photo 2 Solid-liquid separation unit

Clean Coal Technologies in Japan

4. Features of Hyper-coal- Ash content is decreased to 200 ppm or less. The concentrationof alkali metals (Na, K) is decreased to 0.5 ppm or less by ion
exchange.
- Calorific value increased by approximately 10-20% versus thatof original coal.
- Inorganic sulfur is completely removed.
- Heavy metal content is significantly decreased to 1/100 or less.
- Residue coal, which amounts to 30-40% of original quantity ofcoal, can be used as steam coal.
- Low production costs: about $100/ton of Hyper-coal (HPC).
- HPC has excellent ignitability and combustion properties.
- HPC exhibits good thermal plasticity, and is a good carbon
material for direct reduced iron and for smelting nonferrous metals.
- Since HPC is rich in volatile matter and is free from ash, it is an

Photo 3 Test apparatus for continuous manufacturing of Hyper-coalexcellent gasification feedstock, and it is expected to improve theefficiency of gasification.
5. Configuration of Hyper-coal-based high-efficiency power generation system
Overseas mining site
(coal mine)
Roughly de-ashed coal(ash content: 5% or less)Ion exchange vessels
remove alkali metals thatcause high-temperature
corrosion.

Coal is mixed with the solvent,and the mixture is pressurized
and heated to dissolve thecoal’s organic portions into thesolvent. Insoluble ash is treatedby the settler with gravity. It isremoved as residue coal. Thesolvent,containing
thedissolved coal, is sent to the ion
exchange vessels.

The solution is flash-sprayed
into the drying tower toseparate the solvent. The
solvent is recovered for reuse.

The gas-turbine combined-cycle power generation system is a power
generation system that combines a gas turbine with a steam turbine. With a gas
turbine operating at 1350oC, CO2 emissions are reduced by approximately 20%
compared to a pulverized coal-fired power generation system.

Conventional power generation system. Power isgenerated by combusting the residue coal.

6. Concept of Hyper-coal based power generation system

7. Research and development timetable

Post-evaluation

Interim evaluation76