Project Subjects
Advanced Utilization Technology of Biomass and Waste
Background and Objective
Electric power companies are promoting the mixed ﬁring of biomass at coal-ﬁred power plants, which isone of the efforts for reduction of carbon dioxide emissions. This leads to more use of biomass fuel. However,
it is difﬁcult to secure a large amount of biomass fuel, so it is important to develop new business models considering the potential of biomass fuel. This project has two aims. One is the development of potential evaluation
technology, which supports a new biomass business. The other one is the development of the advanced utilization
technology of biomass. These technologies accelerate the creation of a recycling society.

Main results
1. Evaluation technology of domestic waste potential for power generation
In the PFI business etc., it is important to select an optimal scale when the power generating unit is introduced into the waste treatment facility. We investigated the introduction situation of the power generating unit
to the general waste treatment facilities of the municipality. The result shows that the power unit has not been
introduced into the waste facilities of throughput 100t/d or less. The introduction case with the power plant wasexamined according to the throughput based on above (Table 1). As the result, the region where the large-scale
power generation by the wide-area waste collection becomes possible is limited, and it is effective to introduce ahigh efﬁciency power generation unit into the waste treatment facilities of throughput 100t/d or less to expand theamount of power generation (Fig. 1).
2. Advanced utilization technology
1) Assessment of biomass storing safety
For establishment of safety guidelines of biomass storage, the spontaneous heating accelerated testing ofRDF (Refuse Derived Fuel) was carried out. As the result of the test, it succeeded in conﬁrmation of the RDF
temperature rise by the spontaneous heating and the generation of CO (Fig. 2).
2) Development of biomass carbonizing gasiﬁcation technology
To establish the carbonizing gasiﬁcation technology, it is necessary to understand the carbonization and gasiﬁcation characteristics of a biomass in which moisture and volatile matters are high. As the result of the water
addition gasiﬁcation test by the carbonized gasiﬁer with the pellets of red pine and EFB (Empty Fruit Bunch),
it succeeded to operate the carbonized gasiﬁer in 30% moisture biomass without increasing the gasiﬁcation
performance. And also, we showed that the concentration of tar in the syngas is governed by the temperatureof the reforming area in the gasiﬁer. This temperature is useful as an operational index of gasiﬁer to control
the concentration of tar (Fig. 3).
3) Development of small-sized next-generation gasiﬁcation technology
We are developing a molten carbonate gasiﬁcation process through which gas puriﬁcation is possible at thesame time as gasifying for a small-scale dispersed power system. In this process, because moisture in thefuel acts as a gasifying agent, the hydrogen concentration and heat value of syngas are high. The prototype
experimental apparatus of throughput 30-100 kg/d has been designed and produced (Fig. 4) based on thefundamental experiment result of gasiﬁcation performance to the temperature of molten carbonate [M08024].

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Stable Power Supply Technology
Table 1 Case of examination

Output [GWh/y]30,000Installation condition atreplacement

25,0001

Large-scale incineration
waste 300t/d or more

15,0002

Case1 & replacement within
5 years and broad areacollection from 50km range

3

Large-scale incineration
waste 200t/d or more

4

Middle-scale incineration
waste 100t/d or more

5

Small-scale incineration
waste 100t/d or lessCase1: over 300t/d
Case2: Case1+Wide Area
Case3: 200-300t/d
Case4: 100-200t/d
Case5: 10-100t/d

20,000Efficiency 30％

High
Efficiency

10,0005,00002010 2015 2020 2025 2030 2035

2010 2015 2020 2025 2030 2035[y][y]

Fig. 1 Introduction effect of power unit
Difference of replacement time greatly inﬂuences the introduction amount.
High efﬁciency power unit and its installation at 10-100t/d scale incineration
plant for the expansion of waste power generation.

90

90
Inlet air temp.

80

Outlet CO Conc.

70
RDF temperature

Spontaneous Heating byFurmentation and Oxidation

RDF Temp.

8070

Initial Spontaneous
Heating by Chemical
Diffusion

60
5060
50

40403030

CO Generation at
Exoergic

20

CO concentration [ppm]

Case

Efficiency 10％2010100005101520[day]25303540Fig. 2 Trend of RDF/air temperature and CO concentration
RDF temperature is higher than inlet air temperature. CO generation at exoergic is able to be conﬁrmed.

Tar concentration [g/Nm 3]

2.0Red Pine
EFB
1.5
1.0
0.5
EFB：Empty Fruit Bunch

0.0
960

980

1000

1020

1040

1060

1080

1100

Temperature of reforming area in the gasifier [degC]

Fig. 3 Correlation between Tar and temperature
Tar concentration depends on temperature of reforming area in
gasiﬁer, and is lower than 1.0g/Nm3 to maintain a temperatureof 1020degC or more.

Fig. 4 Molten carbonate gasiﬁer
Molten carbonate plays a role of dehalogenation agent
and desulphurizer at the same time as supplying heatfor gasiﬁcation reaction as a heat transfer medium.

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