Effect of Addition of Mixed Gas Including Hydrogen onReaction Behavior of Pulverized Coal
BackgroundIn the steel industry, establishment of a new ironmaking process to reduce CO2 emissions is being studied.
As on of them, a method of blowing hydrogen-based gas flue together with pulverized coal is considered

COG（Coke Oven Gas）Iron ore
CokeTar reforming
Limestone BFG（Blast Furnace Gas）

Coke ovenHigh temperature air
Pulverized coal

H2、CH4、CO

Schematic diagram ofCOURSE50 process
Blow pulverized coal, hightemperature air,H2, CH4,
CO into the blow pipe.

Blow pipeTuyere

Hot metal(Fe)Steam gasification
C + H2O = H2 +CO
CO2 gasification
C + CO2 = 2CO

Blast furnace

In blow pipe,H2,CH4 ,CO
combust and produce.

Gasification of pulverizedcoal by CO2, H2O.

Objective：Elucidation of gasification behavior of coal char at high temperature

Research contents

Using a thermogravimetric apparatus
Consider the following contents
・Temperature dependence⇒1273, 1473, 1673K
・Coal type dependence⇒Coal S(Low volatile), Coal E(High volatile)
・Gasifying agent dependence⇒CO2, H2O(steam)Experimental apparatus

Formulation
Experimental result•

Volumetric model𝑑𝑋= 𝑘𝑣 (1 − 𝑋)
𝑑𝑡•

Grain model
2𝑑𝑋= 𝑘𝑔 (1 − 𝑋)3
𝑑𝑡

•time

𝑋:Conversion[-]𝑡:time[s]𝑘𝑣 :Rate constant(volumetric[1/s]
𝑘𝑔 :Rate constant(garin)[1/s]
𝑘𝑝 :Rate constant(pore)[1/s]𝜑:Pore constant[-]

Pore model𝑑𝑋= 𝑘𝑝 (1 − 𝑋)𝑑𝑡

1 − 𝜑 ln(1 − 𝑋)Measurement of unburned carbon in ash by LIBS
Background• In the coal gasification process, harmful traceelements in coal are a problem.
• It is necessary to monitor in real time.
灰中未燃炭素の成分計測が必要

Conventional method

LIBS※

Pretreatment of samples required

Component measurement in molten
steel is possible

It takes time to adjust components

Time to component adjustment is earlyObject
Determination of optimum analysis conditions
for unburned carbon measurement in ash※Laser Induced Breakdown Spectroscopy

research content
Ash inSample

Ash Feeder

lens

lens
Spectroscope＋ICCD

Gas
Nd:YAG
Laser
Nd:YAGレーザー
OutletIrradiate the sample with laser

ICCD：

A detector capable ofmeasuring light of nanosecond order

Plasma light is generated
from the sampleMeasured with spectrometer and ICCD

Spectroscope: Measure electromagnetic
wave spectrum of light

Preparation of calibration curve of carbon in ash using ratio with silicon

Control of the Ash Deposition on the Surface of Heat Transfer
Tubes in Pulverized Coal-fired Boiler
BackgroundAsh deposition in pulverized coal-fired
boiler causes problems.
Slagging
Molten ash particles collide with thefurnace wall, and form ash deposition
layers.
Fouling
Molten ash particles deposit on heattransfer tubes, and form ash deposition
layers.
 Operating troubles
 Decrease of thermal efficiency

Ash deposition
reduction

High efficiency

CO2 Reduction

Objectives
Reduction of ash deposition inpulverized coal-fired boiler

Research content
1. Ash deposition experiment by verticalash deposition furnace
2. Study on differences in ash deposition
characteristics by thermodynamics
equilibrium calculation
3. SEM/EDX observation of ash samples

Schematic of vertical furnace forash deposition experiment

Fraction of liquid slag [wt%]60

Calculation result (1200C)
Fe₂O₃50

NiO

K₂O

40

Al₂O₃30

CaO
TiO₂20

SiO₂10

Na₂O

MnO0SUS304
SUS304

Alloy1NiSAAlloy2
Alloy3
NiSA-N1
50Ni-50Cr

Clarify the production of NOx by burning waste
Burning waste
NOx production
Purpose• Clarify NOx mechanism
for burning waste
Sample：RDF
Refuse Derived Fuel
Made of general waste

RDF

Stoker image

ResultExperiment
100

20.0
NOx80

15.0

60

10.0

40
20

5.0

0

0.0-100

Butch furnace

O₂100

300
Time[s]500

Burning Simulation（LOGE）

O₂ [%]NOx [ppm/g(sample)]

Burning RDF in butch furnace
Measuring gas and weightAdhesion characteristics of Si compounds
on the denitration catalyst surface
Background

Attention to coal as an energy source
High reserves available
Ubiquity of reserves

large amountsof NOx emissions

Increase of the need to improve catalysts for NOx reduction
NOx removal technology
SCR：Selective Catalytic Reduction
4NO + 4NH3 + O2 → 4N2 + 6H2O
2NO2 + 4NH3 + O2 → 3N2 + 6H2O

Degradation of catalyst performance due to various causes
Si compound attached

Cause of deterioration
Mapping analysis

Line analysis

TEM/EDX(catalyst used for 6 years)

TEM (Transmission Electron Microscope)Adhesion characteristics of Si compounds
on the denitration catalyst surface
Objective
Si is a cause of catalyst deterioration.
Adhesion possibility of the Si compoundon the catalyst surface
and Catalyst performance evaluation

Content1)Exposure test
・Siloxane gas kept concentration wasexposed to a catalyst heated to 350℃ .
・ Attach SiO2 .
2) Immersion test
・The catalyst was immersed in siloxane.
・Firing in a heater heated to 400℃ .
→SEM/EDX→Catalyst performance evaluation
SEM (Scanning Electron Microscope)
EDX (Energy dispersive X-ray spectrometry)

Exposure test Pattern diagram

Siloxane M2(hexamethyldisiloxane)

Immersion test Pattern diagram

Elucidation and Control of the Ash Deposition
Mechanism in Pulverized Coal-fired Boiler
Ash deposition in pulverizedcoal-fired boiler causes problems

HeattransferSlagging
Molten ash particles collide withthe furnace wall, and form ash
deposition layers

AshFouling
Molten ash particles deposit onheat-transfer tubes, and form ash
deposition layers

 Operation troubles
 Decrease ofthermal efficiency

Fowling in the pulverized coal
combustion boiler for electricpower business(After 2 years operation)

Elucidation and control of the ash deposition
mechanism in pulverized coal-fired boiler
Ash deposition
reduction

High efficiency

CO2
Reduction

To reduce ash deposition…

Focus on thermal spraying

Heat transfer tube
(JIS-SUS304)

Thermal spraying
Thermal spraying material molten byarc or gaseous plasma are sprayed
to coat the material surface

Ni alloy(thickness：200μm)

Contents

1. Ash deposition experiment
2. Study on change in ash deposition characteristics
by thermodynamics equilibrium calculation
3. SEM/EDX observation of ash samples afterWet biomass gasification with oxygen-enriched air
renewableenergy13%

BackgroundFossil fuelAtomicenergy5% Cause of global warming Limited resources

Oil32%
Natural gas
21%
Coal
29%

Biomass
Advantage
 Carbon neutral Renewable Big resources

Reference: IEA Renewable Information 2014

Disadvantage
 Low energy density
 High gathering and reserving cost

Demand on high efficiency gasification technology

Wet biomass gasification with oxygen-enriched air
Biomass

In the past
Air, H2 O・Dry→ Gasification

Biomass・Energy comsumption for drying biomass
black pine pellets

Direct gasification of wet biomass

Pyrolysis&Combustion

introduce oxygen-enriched air

Gasification

Contents
・Optimize gasification condition(O2 concentration , additional water , Temperature)
・ Measuring temperature distribution in the reaction tube
・Syngas analysis with Micro-GC(TCD) and GC-14A(FID)

Syngas（CO，H₂）
Packed-bed gasifier

Ash particle behavior in reaction process of coke
Role of coke in blast furnace

Ironmaking process
Limestone
Iron ore
Coke

Fusing zone

・Heat source (combustion )・Generate reduction gas (gasification )・Carburizing source
・Maintaining aeration and liquid permeability

Hot air
Pulverized coal
The most important for stable operation of blast furnace

Tuyeremolten iron

Blast furnaceCoke

Ash particles in coke andpulverized coal

RacewayForm raceway shell

Pulverized coal
Raceway shell

Breathability of lower partof blast furnace lower

PurposeSchematic drawing near the raceway shell

Elucidation of ash particle behavior
in reaction process of coke

Ash particle behavior in reaction process of coke
Preparation of sample for analysis

Emission gas

Watercooking
jacketResin filling

Furnace moves
up and down

Cooling water

Seal gas

Electric balance

Weight dataCutSample

Polishing

Mass flowN2O2Cooling water

CO+CO2CO 22 mm

Carbon coating

Cross section analysis
・Ternarization of cross section
・Analysis of ash, carbon , pore

2 mm

1400℃Combustion SEM image 1400℃ Gasification SEM image· Combustion, large ash particles
exist near the interface⇒Combustion reaction proceeds
near the interface
・Gasification, many void are
distributed as a whole⇒Gasification reaction proceeds
even inside coke

Degradation behavior of ＳＯＦＣ
Benefits of SOFC！Reduced power
generation efficiency

CO + H2！Decrease of celllife

CO2 + H2O

H2 CO CO2 H2H 2 H 2O H 2 H 2 O
O2- O2- O2O2O2O2O2- O2O2 O 2 O2O2AireACurrent

 loss is small and higher
power generation efficiency
can be obtained because
electric energy can be takenout directly.
 SOFC is composed of ion
conducting ceramics andoperates at hightemperature of 900 ~
1000 ℃, so it is possible toobtain higher power
generation efficiency by
performing combined gas
turbine power generation．

Minor constituents in practical SOFC fuelsSulfur –related impurities
Halogen-gas(Cl2 gas in water ,HCL in coal gas etc.)
Ammonia(Biogas)
Aromatic compounds(Petroleum-related fuels)e-◆Schematic diagram of chemical reaction of fuel cell

studyPurpose of study

アノード集電体

電解質

カソード◆Schematic diagram of
power generation cell・Analyze degradation
characteristics of SOFC
by trace hydrocarbon inbiomass gasified gas

Study contents
・Thermodynamic
equilibrium calculation
By Factsage

・Electrical generation
experiment・ Surface observation ofcells before andafter Electricalgeneration experimentusing SEM/edx

Biomass and coal co-combustion behavior
Primary energy supply in Japan

Background

Reliance of fossil fuel is very high• Fossil fuel is limited• High CO₂ emission

In thermal power generation,
movement toward reducing
CO₂ emission is progressing
原子力・エネルギー図面集2016

Expectation of biomass co-combustion incoal fired power generation
Biomass• Organic matter derived from animals and plants
excluding fossil resources and can be used asenergy source• Biomass energy don’t emit CO₂ and it is effective
as measures against global warmingBiomass and coal co-combustion behavior
Objective• Biomass co-combustion in pulverized coal combustion field• Elucidation of the influence of biomass fuel co-combustion rate
and fuel type on flammability and ash properties
Research content•

Evaluation by
thermogravimetric analysis

Schematic of thermogravimetric analysis•

Evaluation of co-combustion behavior by drop
tube electric furnace

Schematic of drop tube electric furnace

21

Elucidation and control of the ash deposition mechanism in biomass-fired boiler
Ash deposition in biomass-fired
boiler causes some problems.

Slagging
Molten ash particles collide withthe furnace wall, and form ash
deposition layers.
・Fouling
Molten ash particles deposit onheat-transfer tubes, and form ash
deposition layers.

 Decrease in thermal efficiency
 Reducing heat transfer
 Erosion of heat transfer tube

Heat exchange tube

Fouling Ash

Enlarged Photo

FoulingObjectives
Reduction of ash deposition in biomass-fired boiler

Contents
1.
2.
3.
4.

Study on ash melting characteristics by TMA
Ash deposition experiment
Study on change in ash deposition characteristics bythermodynamics equilibrium calculation
SEM/EDX observation of ash samples after ash
deposition experimentEquipment of TMA
RIGAKU TMA8311→Measuring of displacement as afunction of temperature and time.

TMA : Thermomechanical Analysis
SEM : Scanning Electron Microscope
EDX : Energy Dispersive X-ray spectrometer

Biomass fired behavior in a fluidized bed
Research BackgroundRenewableenergy ;The reliance on fossil fuel is high in Japan

OthersWhite pellet

Hydraulicpower ;

CoalFossil fuelproduce a lot of 𝐶𝑂2
is limited

2014 year
Reliance 88%
NaturalgasOil ;substitute for fossil fuelBiomass
Advantage・ Carbon neutral
・ Renewable
・ Big resources

Reference: 2014年度の一次エネルギー
国内供給量(経済産業省）

Disadvantage
・ Low energy density
・ Low production per unit density

Expansion of usage of biomass is expected

PKSFluidized bed combustion technology
Experimental device

Principle
Gas is supplied to the particulatematter in the boiler from the bottomof the boiler

The particles are in a hightemperature flow state
Biomass

Fuelis instantly dried and igniteduniformly dispersed

Merit
Fluidized bed

・In-furnace desulfurization possible
・Since it operates at lower temperature (900℃)
or lower, thermal NOx can be suppressed・Compatible with diverse fuelsResearch content

Clarify the influence of the combustion rate and the ash propertyof the combustion rate and fuel type (white pellet, PKS) of
biomass fuel in the fluidized bed combustion fieldAkutsu
Elucidation of mercury capture in exhaust gas
AkutsuAkutsuFeature of mercury
・Poisonous・High volatility

Mercury is of great concern
as an air pollutant

Artificially emissions of mercury in the world

Total emissions of mercury▶1960 tons/year
about 5% of the total come from waste
Come from waste combustion▶98 tons/year（ UNEP (2013) ）Purpose・Reduce mercury emissions by using adsorbents
・Elucidate adsorption and oxidation mechanism

Akutsu
Elucidation of mercury capture in exhaust gas
AkutsuAkutsuMatter・Search of a highly efficient capture agent
・Consideration of a mercury absorption

Analysis on behavior of trace element
during biomass gasification process
BackgroundFossil Fuel
Global warming is caused by CO2 emission
Fossil fuel is limited
Biomass ：Alternative resource of fossil resource
Advantage
・Renewable
・Carbon neutral

PurposeDisadvantage
etc..

・Low energy density
・Low production per unit density etc...

What is the effect of trace element in the biomass?

Analysis on behavior of trace element during biomass gasification processDevice (DTF)

Experiment
Biomass gasification experiment by DTF

Primary gas

Analysis of produced gas by Micro-GC
Collect according to particle diameter by LPI→measure concentration of trace element by ICP

Water inSteamgenerator

Mass flow controller

Biomass feeder

Water inWater out
Injector

Principle (LPI)
Secondary gas

Heater unit

Sampling probe
Micro GC
Water inWater out

N2 CO 2 Ar

LPI: Low Pressure Impactor

DTF : Drop Tube Furnace

Elucidation of biomass gasification behavior in packed bed

Backgroundrenewableenergy13%
Atomicenergy
5%Fossil fuel
 Cause of global warming Limited resources

Oil32%
Naturalgas
21%
Coal29%Reference: IEA Renewables Information 2014

Biomass
Advantage
 Carbon neutral Renewable Big resources

Disadvantage
 Low energy density
 High gathering and preserving cost

Demand on high efficiency gasification technology

Elucidation of biomass gasification behavior in packed bed
Small batch furnace
Gasification

CO,H2

Biomass
Gas fuel
BioBiomasmas
Purposes sTo make biomass gasification
highly efficient

Research content

Elucidation of biomass
gasification behavior

high←compression｜expansion→

Downsizing gasoline engine toimprove fuel economy

Occurrence of LSPIPressure

High temperature and highpressure inside the engine

Occurrence of LSPI

Normal combustion

low-180-90

090

Crank angle[deg]What is LSPI（Low-Speed Pre-Ignition）
In the low rotation and high load region of the engine, the ignition timing
suddenly got faster and abnormal combustion occurred.

180Research content
LSPI・・・It is occurred by self-ignition of deposit in the engine, lubricating oil, or fuel.
⇒The following research is necessary to elucidate the occurrence.

Research content
Object・・・Elucidation of LSPI

①Actual machine test

Proximate analysis
Ignition point analysis
ICP analysis

Figure of TG for Ignition point analysis
and proximate analysis

Figure of ICP※Inductively coupled plasma atomic emission spectroscopy（ICP）

Measurements of unburned carbon in ash by LIBS
Background・Harmful elements(Nox,HCl) come from plants.
・Low combustion efficiency means an amount of unburned
研究背carbon increases.
景Real-time monitoring is needed!

Previous method

LIBS

Preprocessing isneeded for samples.

No preprocessing.
Direct detection.

Principle of LIBSi) Irradiate the sample with Nd:YAG laserii) Plasma gasification of the sampleiii) Measurement the excitation light by Spectrometer and ICCD

Experimentalsystem

Measurement
unburned carbon in
frying ash by LIBS.

SO3 Behavior in Oxy-Fuel Coal Combustion
Oxy-Fuel combustion

Background of research
Utilization of primary energy resources
Oil has become a major in the world•••

Reserves to production ratio: 53 years
Regional reserves are unevenly distributed.
Stable supply is anxiety.

Pay attention to coalrich CO₂(over 90%)

Strong point••

Reserves to production ratio: 109 years
Regional reserves are distributed around the world

Strong point•

Weak point••

Compared to other fossil fuels, CO2 emissions arelarge
Generating NOx, SOx••

Development ofhigh efficiency・CO2 capture
combustion technology

No need for separation and concentration ofCO₂, liquefied and collected can be easily justcooling and compression
With only add the path of exhaust gas
recirculation, available in the remodeling of theboiler traditional
There is a possibility of reduction of NOx

Oxy-Fuel combustion＋Fluidized bed

Fluidized bedfeature•

Desulfurization in furnace can bedone by putting CaCO3 into the bedmaterial•

Mix fluidized gas and fuel efficiently
and combust efficiently•

Reduced thermal NOx emission as it
operates at low temperature(below 900 C)

Purpose of research• Elucidation of combustion characteristics of coal using bubbling fluidized bed• Comparison of combustion characteristics in air, CO₂-O₂, Oxy-Fuel atmosphere