日本エネルギー学会大会講演要旨集
第26回日本エネルギー学会大会

Options to realize sustainable energy supply and demand in the residential sector are energy conservation, demand response, introduction of renewable energy resources, and electrification. This paper provides the prospects of each options.

Some recent developments in pulverized coal combustion simulation including our research are summarized. Tabulated-Devolatilization-Process model has capability to predict devolatilization rate under different heating rate conditions. Oxidation rate of pulverized coal char increases with heating rate when char is generated. Devolatilization process inhibits mass transfer of oxidant to pulverized coal char particle and decreases oxidation rate. The inhibition rate can be modeled with a simple formula. So called Flamelet approach is successfully applied to pulverized coal combustion simulation instead of solving the conservation equations of mass fraction of chemical species and energy.

UN Sustainable Development Goals set 17 goals to transform our world which include ‘affordable clean energy’ in No.7 and ‘sustainable cities and communities’ in No. 11 to be achieved in 15 years. Paris agreement set by UN-FCCC implies zero carbon emissions toward the year 2050. Conventional energy system requires drastic and consistent changes based on an ideal design which satisfies multiple demands in future. The point of design inspires stakeholders to integrate physical, economic, and social dimensions to lead optimized energy configuration with less carbon emissions as well as reasonable costs. A practical approach of integrated design for sustainable energy systems is proposed to aid long term transition toward the Goals based on geographical/dynamic analysis.

Three years passed from the establishment of Fukushima Renewable Energy Research Center in AIST (FREA). FREA is the newest branch of AIST. FREA focuses on the researches and developments for Photovoltaic power, Wind power, Geothermal energy, Shallow geothermal, Energy network and Hydrogen energy. In this paper, the outlines of research and development and future view of FREA are introduced.

The discussion regarding the doctrine of Energy started in 2000 in Japan Institute of Energy. It was the base of the division named "Energy-Gaku" established in 2007. This article discussed how the doctrine would be defined and what its role would be. The author expects that the doctrine of Energy-Gaku provides a platform to connect various energyrelated fields to deal with issues caused by energy use. From the viewpoint of Energy education, the doctrine suggests skill sets for individuals to incorporate. It is emphasized that models to produce values from energy use or resources are important to create new social systems to attain rational and appropriate utilization of energy.

A workshop was held to discuss future energy systems and expectations for the research and development needed to build society after 2050. Twenty-one participants from academic societies on engineering in the energy field discussed their image of future society and the technologies that will become key drivers. Discussions were based on the individual expertise of participants and research trends in academic societies. Common points discussed were: 1) We should discuss this subject based on predictions for future society rather than starting with conventional technology. 2) Viewpoints should comprise not only technological aspects but also social structure transformations and the way people relate to energy. Given the above, a subsequent discussion is being planned for participants with engineering or social background.

100kW three towers circulating fluidized bed have been built for oxygen carrier long time testing for chemical looping combustion. Natural Ilmenite as an oxygen carrier was first tested by used this 100kW three towers CFB facility.

The work studied the Oxygen carrier was further examined in a small fluidized bed reactor with coal char as fuel. The effect of oxygen carrier on coal char gasification gases in containing both H2 and CO was investigated by comparing the gasification behaviour of the (H2 + Oxygen carrier) and (CO + Oxygen carrier).

Chemical looping process is one of the most promising technologies to generate electricity from coal with high efficiency and capturing CO₂ at low cost. This process uses a chemical looping carrier to transfer oxygen from the air to the fuel and generates a CO2-enriched flue gas, which will greatly benefit CO₂ capture. In this study, coal tar reforming experiments were conducted in a 2-stage fixed bed reactor by using two iron-based chemical looping carriers (ilmenite and Fe₂O₃/Al₂O₃) and their tar reforming activities were studied by the effects of an oxidation treatment and weight ratio of coal/carrier. As a result, it was found that when carriers were used as a fresh state, Fe₂O₃/Al₂O₃ had higher tar reforming activity, decreasing carbon yield of heavy tar significantly. On the other hand, ilmenite without any treatment showed only a slight decrease of heavy tar. However, after oxidation treatment at 900°C, reforming activity of ilmenite was increased greatly, almost the same as that of the synthetic carrier. Furthermore, when the weight ratio of coal/carrier increased to 1:50, combustion reaction of volatiles greatly promoted and almost all product gases of both the natural and synthetic carriers were converted to CO₂.

The Osaki Coolgen Project began in April 2012 as an ”Integrated coal Gasification Fuel Cell combined cycle (IGFC) demonstration project” subsidized by the Ministry of Economy, Trade and Industry. This project aims to realize innovative low-carbon coal-fired thermal power generation that combines IGFC, an extremely efficient coal-fired thermal power generation technology, with innovative CO₂ capture technologies. The first stage of this project, to demonstrate the oxygen-blown Integrated Coal Gasification Combined Cycle (IGCC), started in March 2017. The following will explain the project outline.

When low-quality coal is blended, adhesion failure is cause of the decrease in the strength of coke. In the present study, to estimate the three-dimensional position of adhesion failure, coal with Co on its surface was carbonized and broken by a universal tester, and the coke sample before and after the treatment was imaged using X-ray computed tomography (CT), and then, the fracture surface of the sample was analyzed using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). In addition, a coke model considering the three-dimensional position of adhesion failure from images of CT and Co mapping was reproduced, and then stress analyses using the finite element method were performed. As a result, the effect of adhesion failure on distribution of stress was small.

To predict coke gasification reactivity, a weight loss of pulverized coke during gasification was measured using a thermogravimetric analysis and the measured data was fitted by the grain model considering particle size distribution of coke. As a result, in CO₂ and H₂O gasification, reaction rates calculated by the model approximately corresponded to those obtained by the experiments, and activation energies and orders of magnitude of frequency factors were independent of the particle size of coke. Those results suggested that the model can reasonably estimate the reactivity of coke.

For the purpose of developing of the coal blending technology applied to various kinds of low rank coal, we investigated the inhibitory influence of kind and particle size of low rank coals on the dilatation of high rank coal. The main findings summarized below.

(1) When the low rank coal whose dilatation value is extremely low is added to high rank coal, the inhibitory influence on the dilatation of high rank coal becomes high. And as the particle size of low dilatation low rank coal becomes finer, it becomes higher.

(2) When the low rank coal is added to high rank coal which starts softening at low temperature, the effect of the difference in kind and size of low rank coal on inhibitory influence is not so large.

Brown Coals are widely distributed all over the world, and reach up to around 1/3 of the total coal reserves. However, from high moisture low calorific value and high spontaneous heating in dried coal, their utilization area is limited at the coal mine area. Therefore, the development of Australian brown coal reforming technology to suitable for power generation resources has been conducted. This paper describes Australian brown reforming technology.

To expand the coal resources for power generation, R & D of Australian Loy Yang Brown coal reforming technology has been conducted. Loy Yang coal has the character of high moisture content, low calorific value and high spontaneous property etc. In order to change Loy Yang coal properties suitable for power generation coal, the changes of characteristic data and calorific value during carbonization were studied.

As a result, it was clarified that the calorific value of Loy Yang coal was increased equivalent to bituminous coals by using carbonization technology.

Carbon fiber and activated carbon fiber were produced from a low-molecular-weight extract, which we call Soluble, obtained from the degradative solvent extraction of rice straw. The carbon fibers were first produced by the following steps: adjusting the melting behaviors of Soluble, melt spinning, stabilization and carbonization. The Soluble basis yield of the carbon fiber was around 33%. Then the carbon fibers were activated under a stream of N₂-steam mixture at 850 °C and 900 °C. The BET surface area of activated carbon reached as high as 1882 m²/g at 70 % burn-off at 850 °C.

The effect of elemental composition on the efficiency of steam reforming reaction was estimated. The amount of steam introduction to the reactor was varied with the elemental composition of the hydrocarbon fuels. When the condition of steam reforming reaction was optimized to maximize the cold gas efficiency based on the lower heating value, the steam introduction was not effective to the fuels with the O/C values more than 0.4.

Consumption of subbituminous coal will be expanded due to its low cost and long minable years around the world. However, a control of spontaneous firing at the stock yard is one of outstanding issues for the utilization of subbituminous coal. Therefore, an objective of this study is the elucidation of low-temperature oxidation behaviors of subbituminous coals. Several subbituminous and bituminous coals were selected as experimental samples for low-temperature oxidation. Mass changes of coal samples were measured by thermos-balance at the temperature between 356K and 476K in 50%N₂-50%O₂ atmosphere. Differences of molecular structures of coals between before and after low-temperature oxidation were analyzed by FTIR As a result, the aliphatic carbon in the coal was confirmed to react with oxygen, forming carbonyl group.

This work successfully measured heat generation rates accompanying the air oxidation at 50 to 150 °C for 3 kinds of low rank coals using a TG-DSC analyzer. The heat generation rates measured were well expressed by 3 parallel first order reactions which have the activation energies of several kJ/mol, 10 to 15 kJ/mol, and 55 kJ/mol for all of the coals. It was also found that 200 to 350 kJ/kg of heat is generated when the coals are exposed to air at 150 °C for 30 min. The heat is big enough to raise coal temperature by 150 to 260 °C under adiabatic conditions. The rate equations were well expected to be utilized for the prediction of actual temperature increase.

Vapor – liquid equilibria (VLE) for water + atmospheric residue (AR) systems were measured at 603 – 643 K and 2.2 – 10.2 MPa by a flow type apparatus^[1]. The AR was fractionated into 6 pseudo-components which were characterized by several major components via representative structure determined analyzed with the petroleomics analysis. The physical properties of each fraction were estimated by using a group contribution method. Correlation of experimental data by Peng-Robinson model^[2] (PREOS) allowed to accumulate the interaction parameter k_ij data of water – AR fractions. Consequently, we could propose an empirical equation for predicting k_ij in VLE calculation with PREOS based on the obtained physical properties.

Methane hydrate has been expected as Japan domestic energy resources. As one of enhanced recovery methods for methane hydrate, we have been doing laboratory experiments using exothermic reaction of carbon dioxide (CO₂) hydrate formation since FY2009. This paper shows a CO₂ hydrate temperature-pressure phase diagram when using high concentration NaCl solution. This result shows a possibility of using CO₂ in subsea layers near zero degree centigrade.

In this study, we evaluated the effect of acid injection for enhanced natural gas production. To evaluate it with numerical analysis, we got the parameter about the calorific value in dissolution of Toyoura sand to three acids (Nitric acid, Hydrochloric acid and Sulfuric acid) and the reaction rate of the dissolution. Based on those results, we carried out simulations of the behavior in the MH reservoir in heating process by acid injection. The injection water (50 deg, °C) contained each acid (0.010 mol/L, 0.050 mol/L, 0.10 mol/L, 0.50 mol/L, 1.0 mol/L and no acid). As a result, MH reservoir was more heated in each acid injection than only hot water injection. The total gas production in the 3.0 years from starting the operation is enhanced by 17.2 percent at a maximum. In conclusion, the acid injection to MH reservoir is the good way of enhanced gas production from MH reservoir.

To consider methane hydrate regeneration process, we conducted the methane hydrate formation experiments in artificial unconsolidated sandy cores. In experiments, pressure and temperature were measured during methane hydrate growth inside pore space. The moles of methane hydrate were calculated from gas uptake and mass balance. In addition, we measured pore scale morphology of gas/water/sand interface by using micro-focus X-ray computed tomography. According to the results, the methane hydrate growth processes can be divided into some stages, and hydrate regeneration is easily to occur when a system becomes hydrate stable condition.

A comprehensive understanding of gas storage capacity within crystalline form is important not only from a physicochemical point of view, but also from practical applications such as storage and transportation technology of variety of gases. In case of clathrate hydrate, feasibility of methane gas hydrate has been widely investigated and assessed as new storage and transportation media of methane or natural gases. In this study, amount of carbon dioxide (CO₂) encaged within water cage structures of clathrate hydrates was estimated and compared based on type of crystal structures.

We study the formation or melting process of tetrahydrofuran (THF) clathrate hydrate from polyvinylpyrrolidone (PVP), or polyvinyl alcohol(PVA) aqueous solution as a function of growth rate V and adsorbed KHIs concentration c using the unidirectional growth technique. We have already reported the evaluation method for growth inhibition performance of KHIs for the clathrate hydrate–aqueous solution system. This study aims to evaluate various type of KHI performances, and test the same method for evaluating the dissociation inhibition effect of KHIs on melting hydrate crystals.

Clathrate hydrates are crystalline compounds comprising cage structures of hydrogen-bonded water molecules with guest molecules. Tetra-n-butylammonium bromide (TBAB) is typical ionic guest molecule that is capable of forming semiclathrate hydrates. TBAB hydrates are stable below 286 K, have relatively high latent heats (190–220 J g^–1), and can entrap small gas molecules such as CO₂ and N₂ under milder conditions; the physical and chemical properties of TBAB hydrates as phase change materials (PCMs) in cold and thermal energy storages are studied by several research groups. In this study, the method for evaluating the compositions in TBAB hydrates was investigated.

Natural gas hydrate beneath the sea floor is expected as energy resources. Hydration number of natural gas hydrate decides its quality and depends on the temperature and the pressure (water depth). We applied Raman spectroscopy for the natural gas hydrates retrieved off Sakhalin Island and off Abashiri (Japan Sea and the Sea of Okhotsk) to estimate the hydration number of natural gas hydrates. We confirmed no relation between the hydration number of natural gas hydrates and the water depth. We also checked the effect of hydrogen sulfide on the hydration number using synthetic mixed gas (methane and hydrogen sulfide) hydrates, and found that the molecules of hydrogen sulfide prefer to be encaged in small cages, whereas the molecular diameter of hydrogen sulfide is larger than that of methane. Therefore, we may overestimate the hydration number of natural gas hydrate supposing that they are pure methane hydrate.

The transition mechanisms of methane hydrate from an sI to sH structure, and from an sH to filled-ice Ih structure were examined using time-resolved X-ray diffractometry (XRD) and Raman spectroscopy in conjunction with charge-coupled device camera observation under fixed pressure conditions. The XRD data obtained for the sI–sH transition at 0.8 GPa revealed an inverse correlation between sI and sH, suggesting that the sI structure is replaced by sH. Meanwhile, the Raman analysis demonstrated that although the 12-hedra of sI are retained, the 14-hedra are replaced by additional 12-hedra, modified 12-hedra and 20-hedra cages of sH. With the sH to filled-ice Ih transition at 1.8 GPa, both the XRD and Raman data showed a typical reconstructive transition mechanism.

Pressure dependence of elastic constants (C₁₁, C₁₂, C₄₄) for some sI and sII gas hydrates have been determined by high-pressure Brillouin scattering measurements and their analyses. The values of elastic constants C₁₁ of gas hydrates and their pressure dependences clearly show the differences among gas hydrates, depending on the size and the shape of guest not on the gas hydrate structure. In contrast, the pressure dependence of C₄₄ corresponding to shear stress does not indicate an obvious difference among gas hydrates.

Clathrate hydrates are solid crystalline compounds formed by water molecules and other guest molecules. The water molecules form cage structures and the guest molecules are enclosed in the cages. The understanding of the phase equilibrium conditions of the three-phase system composed of hydrate, water, and guest is crucial for expected hydrate applications. In addition, the cage occupancies of hydrate at equilibrium conditions are also important. We performed the molecular simulations to estimate the three-phase equilibrium conditions and cage occupancies for methane hydrate. The results were compared to other previous data from experiments and simulations.

Natural gas (NG) is predominantly methane and consists of several kinds of hydrocarbon. NG hydrates synthesized from NG incorporate several kinds of hydrocarbon molecules into the host lattice constructed by water molecules. The precise crystal structure analysis of NG hydrates has rarely been performed because the crystal structure becomes more complicated. Neutron beam has high transmission even at low energy. Neutron scattering can easily occur even in samples packed into the thick vanadium container (thickness: 1mm). In this study, the NG hydrate sample was synthesized from granular deuterated ice (D₂O ice), in order to suppress of incoherent neutron scattering from H atoms, under the pressurized NG. The crystal structure analysis was performed under changing temperature from 10 K to 277 K.

The structural variety of tetra-n-butyl ammonium bromide (TBAB) semiclathrate hydrate implies that its crystal structure is relatively soft and easily disordered. To elucidate the structural variety of the TBAB semiclathrate hydrate and to solve the large supercooling for the TBAB semiclathrate hydrate nucleation, the equilibrium pressure– temperature relations of TBAB semiclathrate hydrate were measured at pressures up to 80 MPa by the high-pressure differential scanning calorimetry (DSC). As a pressurizing medium, tetrafluoromethane (CF₄) was used. The dissociation temperature of tetragonal TBAB semiclathrate hydrate increases with the increase in pressure, while the dissociation enthalpy is 192±3 J/g and almost constant at pressures up to 80 MPa. The maximum allowable degree of supercooling is 17.7±0.7 K and independent of the pressure.

Although it is known that ammonium ion is replaced with a part of water cages of clathrate hydrate, it isn't known how much amount of ammonium ions are included into clathrate hydrate with the formation. We investigated how much amount of ammonium ions were included into clathrate hydrate with its formation. Tetrahydrofuran (THF) hydrate, as an analogue for CH₄ and CO₂ hydrate, was formed in a solution of THF with ammonium chloride. The concentration of ammonium ion in THF hydrate (CS) was determined and compared with the initial concentration of ammonium ion (C₀). The ratio of C_S to C₀ (K=C_S/C₀) was determined when the volume ratio of formed solid to liquid was less than 0.9. The K value was 0.28 approximately when C₀ wasn't more than 10 mmol/L. This value was about three times more than that value when ice was formed in an ammonium ion solution.

Semiclathrate hydrates are inclusion compounds consisting of water forming cages and the ionic molecules enclosed in the cages as guest substance. The guest-host electrostatic interactions are significant for the stability of the semiclathrate hydrates. In this study molecular dynamics simulation using ab initio molecular dynamics simulation were performed on the TBAB semiclathrate hydrates to analyze the distributions, vibrational spectra, motions of the guest molecules in the cages. The calculation showed the effect of the anions in the framework of the semiclathrate hydrate and the interactions between ionic guest-host molecules. The proton coordinates of the semiclathrate hydrates for the initial coordinates of the molecular dynamics simulations were also determined to satisfy the ice rule and low potential energy.

While facing increasing domestic gas needs at some industries like electricity sector, Saudi Arabia with world’s leading gas reserves has produced natural gas equivalent to its gas consumption, which means no imports of the hydrocarbon. This country has been different from the other GCC countries like Kuwait, UAE and Oman in the Persian Gulf, which have imported natural gas. This kingdom has kept self-sufficiency in natural gas market while playing roles as leaders of OPEC. How have they given influences on the country? This research aims to analyze backgrounds of past trends of natural gas in Saudi Arabia with relation to trends of power generation and its roles within OPEC, based on facts that many of gas reserves of the kingdom had been associated gas.

The calorie of city gas is strictly controlled in Japan. City gas is produced by vaporizing LNG. The calorie of LNG is too low to meet the city gas specifications. Calorie adjustment is carried out by adding high calorie LPG. When a drastic operational condition change happens, the calorie of LNG right before calorie adjustment changes so rapidly that the control system cannot follow it. This is a big operation issue in LNG regasification plants. On the other hand, Mirror Plant, a Cyber Physical System, is expected to contribute to the realization of smart factory. In this system, the virtual plant perfectly simulates the real plant. It is possible to visualize unmeasurable physical values and predict the near future behavior of the plant. Mirror Plant has been already introduced to commercial LNG regasification plants in Japan. In this paper, examples that Mirror Plant supports calorie adjustment operation are introduced.

Carbon Capture and Storage (CCS) technology, which is currently being developed around the world, could become a practical countermeasure to reduce emissions of the greenhouse gas. Depleted petroleum reservoirs and aquifer have been proposed as candidate sites of CCS. The long-term aim of this research is to establish a bio-technological system to convert geologically-stored CO₂ into methane, as an energy resource. To develop a means for the conversion, we focus on technological application of a bio-electrochemical system using microbial catalyzed electrode (bio-cathode).

It has been demonstrated by the experiment that aqueous solution particles of potassium carbonate functioned as a liquid catalyst for hydrogen production and as a CO₂ absorber and aqueous solution particles of potassium bicarbonate as a CO₂ producer and aqueous solution particles of potassium carbonate as a liquid catalyst for carbon production. It has become clear that hydrogen was produced by the reaction of steam with ethanol vapor and carbon was produced by the reaction of hydrogen with CO₂. The max of hydrogen production rate was at 57.3°C and 57.4°C. Heat equilibrium temperature was 57°C. And the max of carbon production rate was at 65°C. Finally, from the analysis of the experimental data, I think that the produced pure carbon is “a graphene” made of a carbon hexagonal mesh face.

Catalytic activity of titania supported palladium, which was prepared by means of the incipient wetness impregnation, for hydrocracking of oleic acid was investigated in order to study production of liquid hydrocarbon from vegetable oil. The catalytic hydrocracking of oleic acid was carried out at the temperature ranging from 290°C to 350°C under the initial hydrogen pressure of 2 MPa. A major product of the catalytic hydrocracking was heptadecane, and a small amount of octadecane was produced through the deoxygenation pathway. An amount of carbon dioxide produced from the oleic acid indicated that the decarbonylation pathway was prior to the decarboxylation one for the conversion into heptadecane. At 350°C, oleic acid or its hydrogenated derivative seemed to be dimerized into the major by-product.

The present authors have been developing new bio-diesel HiBD (High Quality Bio-Diesel), which is composed of a mixture of hydrocarbons containing straight chain and branched paraffins and olefins. Although production technique of this fuel is close to industrialization stage, adhesion of the catalyst particles is a serious problem, which is caused by coke formation during reaction. In the present work, we demonstrated a stable long run operation for 30 h with a new slurry phase reactor using a hydrotalcite catalyst. Catalyst regeneration by air oxidation was also investigated.

Renewable gasoline production from oleic acid (OA), a major constituent of plant oil, was studied by oxidative cleavage and subsequent decarboxylation. Oxidative cleavage was conducted with KMnO4 as oxidizing agent to cleave OA into two short-chain fatty acids; pelargonic acid (PA) and azelaic acid (AA). They were then decarboxylated with Pd/C catalyst to produce hydrocarbons in gasoline range. We determined separately the optimum reaction conditions for both reactions, and found that the process worked well to produce the designated hydrocarbons for PA. However, the conversion of AA into hydrocarbon was only around 70mol%, due to the production of volatile compounds such as methane, ethane and propane.

To improve productivity of biodiesel fuel (BDF), preparation of the noble catalyst that consists of magnetite and mesoporous silica bearing organic base has been studying for our research work. The magnetism makes it easy to reuse the catalyst for the transesterification to produce biodiesel, and mesoporous silica is crystallized over magnetite in the expectation that a large amount of silanol group brings about an increase in the bearing site. Primarily, mesoporous silica bearing organic base was prepared as the model catalyst for verifying the expectation about the increased catalyze activity. Also, the preliminarily coat of amorphous silica to magnetite was tested, for protecting it from the acidic condition to crystalize mesoporous silica.

The hydrocarbon production process from Botryococcus braunii (B.braunii) cultured in seawater medium was developed in this study. Seawater culture improved hydrocarbon extractability of B.braunii slurry by non-polar solvent, such as hexane, and increase the size of the colony. These effects could save the energy consumption in collection and concentration of B.braunii and hydrocarbon extraction from the concentrated slurry, and could improve total energy balance of hydrocarbon production from B.braunii.

Botryococus braunii, BOT-22 can be a producer of hydrocarbon which is secreted naturally from the body and accumulated in the colony that the strain makes. Content of hydrocarbon of the strain was from 30 to 50 wt%-dry cells depending on the cultivation phase. Because the conventional thermal-drying process for the algal biomass before an extraction process using organic solvent needs both high energy-inputs and costs, it can be useful that the hydrocarbon is recovered through a wet-extraction method. In this work, the new wet-extraction system was developed to control a colony-disruption and to recover hydrocarbon effectively. In the experiments, the colony-destruction treatment was conducted by flowing culture media (biomass slurry) through a capillary nozzle. After that, n-heptane was rapidly contacted to culture media and then, the solvent contained the extracted hydrocarbon. The results of quantitative analysis of hydrocarbon using gas chromatography showed that hydrocarbon was more effectively extracted at higher flow rate of biomass slurry. From the available experimental data, a dimensionless parameter of Reynolds number could dominate the extraction efficiency.

In this study, we burn the bamboo powder to know the mechanism of clinker. We carried out the mass change, mesh surface observation and also measured the adsorption amount and size of clinker. The following results were obtained. In the process of clinker formation, two stages were confirmed. Firstly, as the emission of volatiles from bamboo pyrolysis and their combustion at about 1000 K occurred, the metal oxides with low melting point and about 10 μm particles are adsorbed on the stainless steel mesh. Secondly, as char combustion at about 1200 K occurred, there could be two cases of clinker generate as follows. For case one, the small particles with low and high melting points deposit repeatedly and change to clinker in a large massive state. For the other case, lump is adsorbed by the high melting point oxide and small particles due to the low melting point oxide adhere so as to cover the giant lump and become huge.

β-zeolite-alumina composite-supports were prepared by a conventional kneading method and a sol-gel method using alumina with mesopores as a matrix. Ni, Mo and Pt were supported on the composite supports to prepare PtNiMo catalysts. Dehydrocyclization-cracking of soybean oil to produce aromatics was conducted under atmospheric pressure of hydrogen and at as high temperature as 500°C to investigate the influence of kinds of zeolite and the preparation method of supports. It was found that Pt/NM/β(37)60A and Pt/NM/β(37)75A(sg) gave the high selectivity for liquid fuels.

Pyrolysis is a promising method to convert biomass and plastic mixture to useful materials. In this work, we investigated the co-pyrolysis behavior of cellulose and polypropylene(PP) mixture. In the presence of PP, yield of levoglucosan was diminished, and the char yield was enhanced. Cellulose did not influence on the results of PP pyrolysis. These findings differ from co-pyrolysis behavior of beech wood and polyethylene(PE) carried out, previously which might be due to the lower thermal conductivity of PP than that of PE and the presence of tertiary carbon atom of PP.

Many kinds of biomass, such as bark contaminated with earth and sand, are still dumped as waste materials. On the other hand, asphalt plants consume a large amount of fossil fuels to produce road-paving asphalt mixture. Therefore, it is very effective to reduce fossil fuel consumption if the difficult-to-use biomass is utilized as fuel for asphalt plants. We have then developed a carbonization process and a burner combusting the pulverized char to utilize them for asphalt plants. The carbonization plant consists of a rotary kiln heated externally and a hot gas generator burning the volatile matter evaporated from the biomass. The burner combusts the pulverized char made by the carbonization plant with A fuel oil at desired ratio of char and oil. In this presentation, we report the plant and burner, and their operation results.