Part 2 CCT Overview
Multi-purpose Coal Utilization Technologies (Liquefaction Technologies)

4A2. Bituminous Coal Liquefaction Technology (NEDOL)
Research and development: New Energy and Industrial Technology Development Organization; Nippon Coal Oil Co., Ltd.
[Sumitomo Metal Industries, Ltd.; Idemitsu Kosan Co., Ltd.; Nippon Steel Corp.; Chiyoda Corp.; JFE Steel Corp.; Hitachi Ltd.; Mitsui Coal Liquefaction Co., Ltd.;
Mitsui Engineering & Shipbuilding Co., Ltd.; Mitsubishi Heavy Industries, Ltd.; Kobe Steel, Ltd.; Japan Energy Co., Ltd.; Sumitomo Metal Mining Co., Ltd.;
Asahi Chemical Industry, Co., Ltd.; Toyota Motor Corp.; Sumitomo Coal Mining Co., Ltd.; Nissan Motor Co., Ltd.; The Japan Steel Works, Ltd.; YokogawaElectric Corp.; and The Industrial Bank of Japan, Ltd.]
Project type: Development of bituminous coal liquefaction technology, and development of NEDOL Process
Period: 1983-2000 (18 years)

1. Overview of NEDOL Process development

2. Evaluation of NEDOL Process

The conceptual design of a 250 t/day pilot plant began inFigure 1 shows the progress of coal liquefaction technology sinceFY1984. Owing to changes in economic conditions, however, thebefore World War II, expressed by the relation between thedesign of a 150 t/d PP began in FY1988. As a support study toseverity of the liquefaction reaction and the yield of coal-liquefied

the pilot plant, the operational study of a 1 t/d process support

oil by generation. As seen in Figure 1, the NEDOL Process isunit (PSU) was carried out. The 1 t/d PSU, constructed in FY1988

competitive with the processes in Europe and the United Statesat Kimitsu Ironworks of Nippon Steel Corp., consisted of fourin terms of technology, economics, and operational stability, andstages: coal storage and pretreatment, liquefaction reaction,

thus the NEDOL Process is one of the most advanced processesliquefied coal distillation, and solvent hydrogenation. Over thein the field, reaching a position to shift to commercialization in theten-year period from FY1989 to FY1998, a joint study team fromshortest amount of time.

Nippon Steel Corp., Mitsui Coal Liquefaction Co., Ltd., andLarge

Technology overview

Nippon Coal Oil Co., Ltd. conducted operational studies on nine

Third generation

Yield of coal-liquefied oilcoal grades under 72 conditions. Through the 26,949 hours ofcumulative coal slurry operations, the stability and the overall
operability of the NEDOL Process were confirmed, andoptimization of the process was established. Finally, thenecessary design data was acquired. Construction of the 150 t/dpilot plant was launched in 1991 at Sumitomo Metal Industries,
Ltd.’s Kashima Steelworks (Kashima City, Ibaraki), requiring

NEDOL Process
CC-ITSL Process (U.S.A.)
IGOR+ Process (Germany)First generation
Processes in the ’40s

main facilities: the coal treatment unit, the consisted liquefaction
reaction unit, the liquefied coal distillation unit, the solvent

Severehydrogenation unit, and the hydrogen production unit.

Severity of reaction

Liquefaction/reaction unit

Coal liquefied oil distillation unit
Gas
Separator

Atmosphericpressure
distillation column

Circulation gas compressor
HydrogenSlurry mixer
Hydrogencompressor
Slurry tank

170kg/cm2G(16.7MPa)
450oC

Preheating
furnaceSlurry heatexchanger

Heating
furnace

Fuel

Hydrogen

Fuel

Preheating
furnace

110kg/cm2G(10.8MPa)
320oC

Residue
Solvent booster
pump

Stripper

Kerosene/gas oil distillate
Vacuumdistillation
columnLiquefaction
reactor(3 units)

Separator

Drying/pulverizingunit

NaphthaHightemperature
separator

Let-down valve
High-pressureslurry pump

(Hydrogen-donor solvent)

Mild

Fig. 1 Relation between the severity of liquefaction
reaction and the yield of coal-liquefied oil

Iron-based
catalyst

CoalCoal bin

Processes after the oil crises

Smallnearly five years for completion. The pilot plant consisted of five

Coal preliminary
treatment technology

Second generation

Solventhydrogenation
reactor
Fuel

Solvent hydrogenation unit

Fig. 2 Bituminous coal liquefaction process flowchart
59(Heavy distillate)Clean Coal Technologies in Japan

3. Features of NEDOL Process
The NEDOL Process is a coal liquefaction process developed

core process stages; andexclusively in Japan. The process has integrated the advantages(4) applicability to a wide range of coal ranks, ranging from sub-of three bituminous liquefaction processes (Direct Hydrogenation

bituminous coal to low coalification grade bituminous coal.

Process, Solvent Extraction Process, and Solvolysis Process),
Catalysts

thus providing superiority in both technology and economics. The
Liquefaction catalyst

Hydrogenation catalyst

48.2
51.0
0.8
Other (wt%)
Specific surface area (m2/g) 6.1
0.7-0.8
Size of pulverized catalyst [D50]( m)Ni-Mo/ Al2O3
1900.7Micropore volume (ml/g)
14.5
Mean micropore size (nm)advantages of the NEDOL Process include:(1) attaining high liquid yield under mild liquefaction reaction

Catalyst composition Fe (wt%)

conditions owing to the iron-based fine powder catalyst and to theS (wt%)

hydrogen-donating solvent;(2) producing coal-liquefied oil rich in light distillate;(3) assuring high process stability because of the highly reliable

Catalyst composition Fe (wt%)

Specific surface area (m2/g)

4. Typical reaction conditions of NEDOL Process
Liquefaction reaction
Temperature

450 C
170kg/cm2 GO

PressureType of catalyst

Iron-base fine powder catalyst
Added amount of catalyst 3 wt%(dry coal basis)

Solvent hydrogenation reaction

Slurry concentration 40 wt% (dry coal basis)

Temperature

Slurry retention time

Pressure

60 minGas/slurry ratio
700Nm3/t
Hydrogen concentration in recycle gas 85 vol%320 C
110kg/cm2 G
Ni-Mo-Al2O3
1 hr(-1)
O

Kind of catalyst
LHSV

Gas/solvent ratio
Hydrogen concentration in recycle gas

500Nm3/t
90 vol%5. Pilot plant: Objectives and achievements
Development objectives

TargetAchievements

1. Yield of coal-liquefied oil

For standard coal, 50 wt% or higher
yield of light to medium oils, and 54 wt% of higher total yield

With standard coal, attained 51 wt%
yield of light to medium oils, and 58 wt% of total yield

2. Slurry concentration

40-50 wt% of coal concentration in slurry

Stable operation achieved at 50 wt% of coal concentration in slurry

3. Added amount of catalyst

2-3 wt% (dry-coal basis) of added amount of iron sulfide-base catalyst Operation conducted in a range from 1.5 to 3 wt% of added amount of iron sulfide-base catalyst

4. Continuous operation time

1,000 hours or more for standard coalContinuous operation of 80 days (1,920 hours) achieved with standard coal

5. Range of applicable coal grades

Three coal ranks or more

Operation conducted with a wide range of coalification ranks, namely Adaro coal, Tanitohalm coal, and Ikejima coal

6. Research and development timetable of NEDOL Process pilot plants(Fiscal year)

~1983

1984

1985

1986

1987

1988

250 t/d PP design

1989

1990

1991

150 t/d PP design

1992

1993

1994

1995

1996

Construction

1997

1998

Operation

Core technology research and support study

7. Research and development results
All the acquired data, including the pilot plant data, the basic

Furthermore, the developed materials and new processes areresearch data, and the support study data, were summarized in a

expected to significantly influence development in other industries.

technology package in preparation for practicalapplication. At the Development and Assessment

Central control building
Solvent hydrogenation unit

Committee Meeting for Bituminous Coal Liquefaction
Technology in the Assessment Work Group of theIndustrial Technology Council, held on December 22,

Fuel tank

Liquefaction reaction unit

1999, the NEDOL Process was highly evaluated:
Coal-liquefied oil distillation unit

"The NEDOL Process is at the highest technology

Coal preliminary treatment unit

level in the world, and has reached the stage whereworldwide

diffusion

isexpected." Thus,

Hydrogen production unit

thedevelopment of coal liquefaction technology in Japan

Storage tanks

has already exited the research and development
stage and entered the practical application stage.

Fig. 3 NEDOL Process pilot plant (150 t/d)References

1) Sadao Wasaka: "Bulletin of The Japan Institute of Energy," 78 (798), 1999.
2) "Development of Coal Liquefaction Technology - A Bridge for Commercialization," Nippon Coal Oil Co., Ltd.
3) Haruhiko Yoshida: "Coal Liquefaction Pilot Plant," New Energy and Industrial Technology Development Organization.
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