General Overview

Energy Engineering Research Laboratory

Brief Overview
Amidst the profound changes of the business environment for energy companies due to the deregulation of the energy/power
market, worsening of global warming and lifestyle diversification, the Energy Engineering Research Laboratory aims at contributing
to (i) the creation of a new highly efficient, clean and low cost power/energy supply system and (ii) the shift towards a recycling-basedsociety while ensuring energy security. The Laboratory intends to achieve this by providing innovative fundamental technologies andpresenting alternative energy sources.
In FY 2007, the Laboratory analyzed the combustibility, characterized the burnt gas and identified relating issues of various
liquid fuels for gas turbines. Basic combustion characteristics of fuel droplets were also identified. The use of these fuels is expected
to increase from the viewpoint of energy security as the supply of LNG is expected to become tight in the near future.
Moreover, the scope of the application of the DME dewatering technology which was developed as a upgrading technology
for sub-bituminous coal was expanded to the removal of ice in cold regions and the removal of oil at normal temperature for thepurpose of environmental conservation and the feasibility of these applications was confirmed. The development of a low cost
technology to decompose volatile organic compounds (VOC) was advanced for the purpose of environmental conservation.
Furthermore, a basic study and examination of the analysis methods were conducted to expand the application scope of fuel cells andheat pumps as highly efficient energy conversion devices. In regard to fuel cells, for performance prediction was expanded to several
types of fuel cells. In regard to heat pumps, research was conducted to enhance the performance. The feasibility of an advanced humid
air turbine (AHAT) system was also examined.

Achievements by Research Theme
Operation and maintenance technology in thermal power generation[Objectives]
To understand the basic combustion characteristics of alternative or new type of liquid fuels, establish a fundamental
technologies for combustion and develop an assessment tool for reliabilities of equipment using under a high temperature environment
at existing thermal power plants, for the purpose of advancing the operation and maintenance technologies for thermal power generation[Principal Results]
・ The requirements for liquid fuel serving gas turbines were clarified. New types of fuels, including non-conventional fossil fuels,
such as oil sand, etc., and biofuels, such as jatropha oil, etc., were evaluated based on the property analysis results and their applicability to gas turbines and the problems were investigated.
・ To evaluate the applicability of palm methylester, a type of biomass fuel, to gas turbines, the evaporation characteristics of a single
droplet under micro-gravity were investigated using a micro-gravity experiment facility.
Fuel reforming and environmental protection technology[Objectives]
To develop base technologies relating to reforming of low grade fuels, coal ash utilization and decomposition of volatiletrace substances for the purpose of contributing to the diversification of fuel and environmental protection[Principal Results]
・ With the DME dewatering technology, the feasibility of ice removal from frozen coal and wood was affirmed at the temperature
below 0 ℃. Furthermore, the applicability of the DME extraction technology to oil removal was confirmed. Oil can be removed
from oil absorbing sheets/oil sorbents having absorbed vacuum pump oil, and also from glass, wood, paper and metal to whichinsulation oil is attached.
・ A VOC decomposing module using a ceria catalyst was developed and its performance for the decomposition of benzene, toluene
and xylene was verified (Fig. 1). An design of a practical scale system revealed a low cost and compact system is achievable.
High efficiency energy conversion technology[Objectives]
To develop fuel cell technologies, clean fuel technologies, heat transfer technologies of refrigerant for heat pumps, heatstorage technologies and an evaluation technology for various energy systems, on the basis for highly efficient energy conversion
technologies in the future28

Energy Engineering Research Laboratory[Principal Results]
・ In connection with a generating technology using fuel cells, performance models were developed for polymer electrolyte and solidoxide fuel cells. On a molten carbonate fuel cell, the dynamic characteristics were discussed and the dynamic model (Fig. 2) focusing on change of gas concentration in the cell was developed. The model clarified the characteristics of overload. Moreover, a new
application of the molten carbonate fuel cells was proposed as a mitigating function of voltage sag.
・ A basic survey was conducted with a view to expanding the scope of applicability of the heat pump technology to agriculture. The
evaluation of the basic characteristics of heat transfer was continued to enhance the performance of heat exchangers for CO2 heatpumps.
・ The feasibility of a AHAT system as a small to medium size, high efficiency power generation system was evaluated and the R&Dissues were identified for commercial plant.

TolueneDecomposing Rate (%)

XyleneBenzene

The decomposing rate is 98% orhigher with toluene and xylene
and 95% with benzene.

Reaction Temperature (℃)

Fig.1 Reaction Test Results for VOC Decomposing Module

PoroseElectrodeGasFilm

Gas
ChannelMaterial balance equation for gas concentration

Changes of gas concentration at the overload current: Gas concentration [mol/cm3],: Electrode volume [cm3],
2: Overload current density [A/cm ],: Space time [s],: Electrode area [cm2]: Volume transfer rate [cm3/s]: Time constant of internal current change [s]Fig.2 Schematic diagram of dynamic model on gas concentration change

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