The philosophy of chemical engineering and the realization of a sustainable society is discussed. According to our goals of achieving a sustainable society and for supporting our population, it will be paramount to evolve to solar energies. Proper training and education will help to establish new identities for chemical engineers, who will make up a broad discipline of sustainability engineering. One of the challenges for chemical engineers will be to design systems for chemical recycle that are truly compatible with the environment. In chemical processes for the next era, it is imagined that design philosophy of "scaling-up" will be changed to one of "numbering-up" for the new series of micro-sized devices and reactors. Chemical processes will be operated increasingly on a local-level in a local environment such that material quantities can be produced as needed or on demand. Chemical education and the development of new career paths for chemical engineers is extremely important. The chemical engineer of tomorrow will require a new chemical engineering system that incorporates many different fields and new eco-disciplines to realize "Sustainability Engineering."

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Chemical engineering has come a long way in the last century and developed to a full fledged discipline. Most importantly, chemical engineering is instrumental in the establishment of many chemical processing industries. Prominent in this group are petroleum cracking, petrochemicals, polymer resins, plastics, synthetic fibers, synthetic rubbers, coatings, adhesives, pharmaceuticals and specialty chemicals. They are essential components of our foods, materials, shelters, transportations, entertainments, cures of diseases, etc. As a group, it normally accounted for nearly 25% of the gross domestic product in a typical developed economy during the 1950-80's. Intellectually, chemical engineering has contributed to the growth of many disciplines especially bioengineering, biotechnology, materials science, micro-electronics, environmental science and engineering, among others. Chemical engineers are recognized leaders of the industry, business and the society.
However, in the last two decades, chemical engineering has gradually being edged out of social limelight, except when there are industrial hazards and pollutions. Chemical engineer no longer commanded the leadership position and professional respect as once has. Many Corporate giants such as Allied Chemicals, Air Products, American Cyanamid, Union Carbide, etc., have been reorganized, restructured, acquired, merged, some many times over, to such extent that can hardly be recognized to provide aspiration for young engineers. How can chemical engineering, as a profession, attract and retain and best talents? Is it at the risk of being marginalized?
To be sure, progresses of science and technology during the last quarter of a century have ushered in the digital revolution and the knowledge-based economy. We have witnessed important paradigms shift regarding how information transmits, corporations compete, operations run, business models gyrate, manufacturing and service merge, skill upgrades and culture changes. Obviously, chemical engineering cannot be immune from these. Chemical engineers, regardless of his/her job in R&D, manufacturing, services, management or education, will be placed in the whirlpool of the change of time.
Digital revolution will uplift chemical plant and chemical business to a different plateau heretofore unseen. Product and process design, lead time, production scale, physical layout, control mechanism, materials management, customer interactions, technical services will all experience unprecedented changes. Mastering these changes will allow chemical engineers and organizations to maintain competitiveness and sustainability. Furthermore, the advent of information technology, genetic engineering and nanotechnology will open many new exciting opportunities.
The contribution of chemical engineers in the knowledge based economy will be manifested in at least three ways: the mainstream role, the expanded role and the unique role. By performing these roles, the profession of chemical engineering will continue to be in the leading edge of the society.

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Despite of serious problems and challenges like overcapacities, reduced profitability, cost pressure, increased competition, and globalization, chemical industry is still quite healthy characterised by higher growth rates and productivity increases than the total industry. In the past the chemial industry could generate its economic prosperity by selling commodities and chemicals produced via process routes which were developed decades ago. This is no longer possible. Globalization and worldwide competition make the commodity market no longer sufficient enough to sustain economic prosperity. The employment rate is decrasing very rapidly due to the cost pressure which results form increased competition. Is the chemical industry following the other traditional industries like steel and coal on their way down?.
The one and only mean to guarantee economic success in the future is to develop innovations which open new fields and markets. Chemical Engineers will play a central role in this process because they are interdisciplinary educated which is essential to create these new innovations. But are the graduates well prepared to fulfil the requirements of the changing enviroment in the chemical industry? Innovation and education are strongly linked together. Only well educated people can turn their ideas into new technologies and products.
This paper describes the current situation and tries to give some answers to the questions metioned above.

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1. the important role of chemical engineering in the economy
2. three challenges of chemical engineering for sustainable developing.
Exhaustion of fossil resource and serious pollution will result in a great evolution of chemical engineering, especially evolution of material route and the evolution of process route.
3. industrial biocatalysis will be one of promoters of developing chemical engineering
4. bioeconomy based on carbonhydrate will take place of petro-econmy based on hydratecabon

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Sustainability development rather than sustainable development is a must in avoiding a catastrophe of ever growing human activities on the earth. Concept of Zero Emissions focuses on development of full utilization systems of natural resources by learning from natural ecosystem structures. This enables minimization of the environmental load from industrial and domestic activities and at the same time increases human livelihood by creating new jobs and revenues through formulation of integrated material utilization systems.
A research project on application of Zero Emission concept to the development of a small island, Yakushima, is briefly introduced. A special emphasis will be laid on an importance of a paradigm shift from the time of economic growth in order that the sustainable human activities may be achieved.

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The sustained development of China's national economy asks for a growing trend on the need of energy. However, the status of energy supply seems dim for the amount of energy resource for each person in China is less than half of that by the world average level. It is estimated that the consumption of the primary energy will reach 3 billion tce in 2020, which would result in a much larger gap between supply and demand. So to vigorously develop the biomass energy and increase the proportion of renewable energy in the energy structure are quite important to China's sustainable development and the national energy security in the future. The resources, technologies and relevant policies of China's biomass energy are introduced and the technical path and strategy planning for promoting the development of biomass energy in China are also discussed in this paper.

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This paper discusses briefly the geographic, demographic, economic, and energy situation in Indonesia. The indigenous energy production and reserve of primary energy are shown, including those which are used for the electricity generation. The gradual shifting from oil to other primary forms of primary energy, particularly to natural gas and coal to supply the domestic energy demand is clearly shown from the national energy. The potential of new and renewable energy are also identified. Particular study to identify the potential of biomass including peat and the type of biomass that is most available for immediate utilizations is carried out. Particular discussion concerning the potential of biomass or peat coal co-fuel to insure the reliable supply, fuel characteristics improvement, and CO2 emission reduction is made.

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1. Background of starting the Eco-town project
The City of Kitakyushu became one of Japan's major industrial centers with the 1901 establishment of the Yahata Steel Works. In subsequent decades, the chemical laden smoke filling Kitakyushu skies was taken as a sign of prosperity for the Kitakyushu region and Japan as a whole. Yet economic development came at the price of clean water and air; by the 1960s severe pollution had dramatically diminished the quality of life for Kitakyushu's citizens and water pollution became so bad that residents called Kitakyushu's toxic Dokai Bay the "Sea of Death." Change came when a small group of concerned women initiated a dramatic turn-around for Kitakyushu by building coalitions that combined city residents, businesses, universities, and the local government to affect a substantial recovery of environmental quality that is most evident in Kitakyushu's skies and rivers today. Kitakyushu actively works to share their experiences such as pollution control, environmental education and environmental oriented industries with other cities that now struggle with the effects of industrialization and conducting extensive international environmental cooperation projects in an effort to build the foundations of a resource-sustainable society.

2. Outline of the Kitakyushu Eco-town project
Kitakyushu is using its experiences from overcoming pollution not only in international environmental cooperation but also in urban planning. Kitakyushu is committed to fostering environmental industries and the creation of a recycling and economic society by promoting "the Kitakyushu Eco-town Project."
Advanced technology of recycling and emission control of the waste is accomplished by the promotion of environmental industry provided by the industrial accumulation in this area. The Eco-town project means the measure which aims at the realization of industry-university cooperation and the production of advanced environment-friendly town.
We take advantage of the technical capabilities accumulated as "the Town of the Production" over 100 years to tackle "The Kitakyushu Eco-town project". In process of pollution conquest, many specialists in industry, academia and government fields have cultivated an original municipal policy including both "industrial promotion measures" and "environmental preservation measures", simultaneously.

3. The 1^st stage of the project
During these 10 years, based on "a zero emission design ", accumulation of recycling industries (20 companies are operated) has been promoted in Comprehensive Environmental Industrial Complex (about 25ha), Hibikinada area, Wakamatsu-ward. And collaboration between companies will have been promoted to execute the zero emission in this area. Moreover, Practical Research Area (about 6.5 ha) has made a large contribution to a new technical development in environmental and recycling fields.

4. The 2^nd stage of the project
Aiming at "the resources recycling" and the "environmental industrial base" city in Asia, the Eco-town area is expanded to the whole city. Moreover, the new industrial creation called a "biomass utilizing project", and "Eco-complex Plan" which utilizes an existing industrial infrastructure and attains energy saving and saving-resources in this area throughout in the city are promoted. Furthermore, the eco-friendly product, equipment, etc. by the medium and small companies in the city are advertised.
In Practical Research area, if the human resource development in the fields of waste and recycling is strengthened, it is supposed that the creation of next-generation environmental industry which utilized alternative energy, micro nano-sized technology, etc. is also addressed by means of the collaboration with the Scientific Research Park.

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For almost 4 years professional institutions involved in accrediting university Chemical Engineering programs have used what is known as "Output Driven Accreditation" guidelines. The concept is that chemical engineering graduates should acquire certain graduate attributes as they progress through the university program (normally of 4 years duration). The lecture summarises the concepts of graduate attributes (outputs) and considers how selected university chemical engineering programs from a number of countries align with professional accreditation requirements. It is of concern that a number of programs do not comply with some of the key outputs that the profession promotes. As an example, we are living in the age of sustainability and responsible chemical engineering professional bodies require that graduates are fully aware of the essential principles of sustainability. There is good evidence that students and graduates in a number of countries have only a very limited knowledge at best, of these principles. There is no doubt that many chemical engineers in industry have only a passing knowledge of the true fundamentals of sustainability and their responsibility in this area. An important consequence of an "output driven" accreditation system is that course curricula are not prescribed for accreditation giving the teaching institution much greater flexibility than hitherto. Hence we can expect to see more specialities arising in chemical engineering programs with full accreditation. An undergraduate program specialising in biomolecular engineering would be expected to arise alongside a traditional chemical engineering undergraduate program both carrying full chemical engineering professional accreditation.

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Chemical engineering is being publicized as the branch of engineering that deals with the chemical and physical processes used to develop and make many products, including pharmaceuticals, semiconductors, artificial kidneys, oil refineries, solar panels, clean water, and biocompatible polymers. Chemical engineers have made major contributions to the technological infrastructure of modern society. In the past decade, chemical engineering is undergoing dramatic changes under the impulse of modern science and technology. Industries are quickly globalizing and engineers are required to do business across their national boundaries.
Chemical engineering has a long tradition and proven methodology of process design with emphasis on commodity chemicals. Nevertheless the chemical industries nowadays are increasingly involved in specialty chemicals (small quantity, batch production, high added value) as well as formulated products. In addition to process design and optimization, which are the major concerns of commodity production, the specialty and formulated product industries face also new technical as well as marketing challenges. In this regard, chemical product engineering is being reemphasized as a new discipline merging several promising areas such as working with multiscale problems, facing complex matter behavior, trying to fulfill society's needs, controlling manufacturing processes, and mimicking biological systems.
All the situations surrounding us call for an examination of the limitations and possibilities of chemical engineering methodology and related education within a new paradigm of product oriented framework. In this talk, we tentatively identify some of the actual and future challenges of chemical engineering education in this changing era to product engineering. Because chemical engineering, a lively engineering science, is unavoidably a part of, not apart from, the society that it serves, our profession must reinvent itself to meet society's expectations. New qualification systems for global engineers are also proposed.

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The Philippine Educational System is such that majority of educational programs for higher learning are serviced by private schools with limited financial assistance from the government. These private institutions supported their operations primarily from tuition and school fees. For example is the chemical engineering education in the country offered by 34 engineering institutions and universities; 7 are state run while 27 others are privately managed. The fundamental problem the private schools face is the shortage of funds that make accreditation by an independent body a low priority budget item. But how do we address the issue of "quality engineering education"? How good a school is? All schools in the Philippines have gone through one form of accreditation. The Commission on Higher Education (CHED), is a regulatory body that oversees the program offerings in tertiary learning institutions and universities in the country. This is the government agency that first determines if schools have adequate resources that could sustain their program offerings as well as could maintain the level of educational quality prescribed by the commission. Schools who have complied with the minimum requirements prescribed by the government have their programs "recognized by the government". This is then viewed as a type of school accreditation by the government. However, "recognition by the government" is inadequate for judging the quality of the school. Thus voluntary, private accreditation provides the opportunity for an institution to attain standards above those prescribed as minimum requirements by the government. The paper will provide an insight of the educational accreditation process that is happening or is supposed to be happening in the country's engineering institutions and universities.

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The quality of Japanese engineers has been kept at high level by the combination of basic training of mathematics and natural sciences at the lower-level schools, high emphasis on education of engineering sciences at higher-level colleges and universities, together with the well-designed on-job training as an engineer at companies. In this way, Japanese engineers have strong royalty to the companies, but do not recognize themselves as independent engineers.
Due to the tendency towards the collapse of the life-long employment system and also due to the globalization of engineer's activity, however, this was started to become a disadvantage for Japanese engineers.
As a part of movements towards this change, it became realized that an accreditation system needs to be introduced to Japan. Thus a new association called "Japan Accreditation Board for Engineering Education (JABEE)" was established on November 19, 1999. The activity of JABEE and the contribution of the Society of Chemical Engineers, Japan (SCEJ) to the accreditation of chemical and chemistry -related engineering programs are reviewed in the present article.

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The dispersion of solids in liquids at high concentration, the suspension of solids in viscous liquids and the preparation of emulsion with a high internal phase ratio are typical problems involving a significant change of viscosities over the course of the process accompanied by the development of strong non-Newtonian properties. Industrial examples include the preparation of paints and coatings, the manufacturing of food products, and suspension polymerization to name a few. Classical mixing technologies to handle these problems range from high solidity open turbines to close-clearance impellers. The main drawback is that they are not necessarily efficient over the whole range of viscosity and/or rheology encountered in the process, especially when working in the laminar regime. For instance, open impellers perform well at low viscosity but generate caverns and segregation at higher viscosities especially in the case of shear-thinning fluids. On the other hand, close-clearance impellers are very poor mixers at low viscosity but outperform all other technologies (except perhaps static mixers) at higher viscosities. In industry, several alternatives are available that are capable of dealing with physically evolving media undergoing for instance a significant change of viscosity, namely planetary mixers and coaxial mixers. Another possibility is the use of single or dual eccentric impellers operated at steady state or in a dynamic fashion. These mixing technologies are most often empirically designed, and there is a very limited scientific knowledge available to optimise their operation.

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We tried in this study to numerically analyze the mixing process for high concentration slurry liquids having a plastic rheological property, and in which unevenness of both, viscosity and concentration, disappear with agitation, from an initial situation in which the viscosities are different in the upper and lower halves of a stirred vessel. We verified the reliability of the analyzed results by comparing them with measurements of mixing time and the power consumption required to attain mixing. The numerical analysis enabled us to understand the correlation equations of the mixing process for a heterogeneously viscous system in which the initial viscosity varies through the vessel and to estimate the mixing performance from a local point of view in the vessel.

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In order to produce product in large quantities at narrow space, the tall vessels stirred with multiple impellers are commonly used, in which, solid-liquid agitation, such as crystallization and slurry polymerization, is operated successfully. However, it is not easy to float and disperse the solid particles throughout the vessel. In order to satisfy this condition, the large impeller is desirable but it is expensive, thus the multiple traditional impellers have widely been used in process industries. However, this system makes considerably wide distribution of particle concentration in a vessel compared with the large impeller. Then, in this study, we studied the suspension of solid particles in the vessel equipped with dual traditional impellers, that is, Rushton turbine, pitched paddle pumping up and down. The combinations of the traditional impellers and the optimal installed position and optimal bottom shape were investigated to satisfy the condition of floating and dispersion that is possible to accelerate mass transfer in throughout the vessel. It has been developed by optical method of particle floating and dispersion and by measurement of the distribution of particle concentration that optimal combination of traditional impellers is pitched paddle pumping down and pitched paddle pumping up, and the optimal clearance of dual impellers is same length of vessel diameter, and the optimal bottom shape of vessel is the profiled shape.

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The effect of impeller diameter for three geometrical similar impellers on solids suspension had been investigated in one of the earlier studies (Mak 1999), it was found that the smallest impeller appeared to be the most energy efficient at all clearances. This study looked further into a series of pitched bladed turbines of same blade width and an impeller diameter range between 0.3T and 0.7T (i.e. non-geometrical similar impellers, with W/D varies). Two impeller clearances, T/4 and T/8, were tested. Round grained sand and water were used as test media. It was found that the geometrical and non-geometrical similar impellers exhibited similar just suspension speed (N_js) and just suspension power (P_js) trends and that the small diameter impellers were more energy efficient than the large ones. The effect of blade width on N_js and P_js were found to be statistically insignificant. This work has once again confirmed that the optimum configuration is a function of both impeller diameter and clearance.

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Flow simulation for a waxy crude that is Bingham-plastic in nature has been performed for pipeline restart. In this paper, the methodology used for temperature, pressure and velocity profile prediction will be discussed. The possibility of restarting the cold gelled fluid and the required time for flow to reach steady state have also been investigated.

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Rayleigh-Benard natural convection of water in a cylinder was measured for the rate of heat transfer under both gravitational and magnetizing force fields. The height of the enclosure is 2 mm and its diameter is 40 mm. This aspect ratio 20 can be expected to provide a Rayleigh-Benard natural convection. The lower plate is electrically heated and upper plate is cooled by running water through a constant temperature bath at 10 C. This cylinder was kept horizontally and coaxially placed in a bore space of a super-conducting magnet as large as 10 Tesla. The center of the cylinder was placed at 111 mm from the coil center of the super conducting magnet so that radial magnetic force component is minimized. The average heat transfer rate was measured by the previous technique (Ozoe and Churchill, 1973). The average Nusselt number was found to agree with the classical experimental data (Silveston, 1958) when plotted versus the magnetic Rayleigh number (Braithwaite et al., 1991) and also with our previous numerical results (Tagawa et al., 2003).

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It is known that a surfactant solution with appropriate counter ion induces the structure of fiber-like micelles in a shear flow field. When the structure is induced, the drag of the pipe flow is reduced. Based on the fact, we presumed that structure of agglomerated particles in a particle suspension also causes the same effect. Thus, we attempted to reduce the pressure drop of the suspension flow by adding a polymer flocculant. In this study, we investigated the change of the pressure drop of the pipe flow with the flocculant concentration. The change of the drag was evaluated by the drag reduction rate defined by the ratio of the difference of the friction factor between water flow and suspension flow to the friction factor of water flow.
It was found that the suspension with polymer flocculant caused the drag reduction under the conditions of particle concentration 1 and 10vol%. In the same flocculant concentration, the water solution of the flocculant (=without particles) also caused the drag reduction. However, the drag reduction rate of the solution was less than that of the suspension with flocculant under certain conditions. The fact shows that the particle enhances the drag reduction.
From the observation of the flocculate in a stationary fluid, it was found that independent agglomerations were formed when the drag reduction was enhanced. The fact shows that the drag reduction is attributed by agglomerated particles. It leads to an expectation that the drag reduction can be achieved in any other solid-liquid suspension if proper agglomeration is formed.

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Drag reduction caused by surfactant solutions is considered to be an effective way to reduce the running cost in closed-loop district heating and cooling systems. Many researches of drag reduction have been highly developed in recent years. It is known that the combine use of a cationic surfactant; Ethoquad O/12) and a counter ion; sodium salicylate shows significant drag reduction. However, there are few papers about the application of drag reduction. We have applied such additives for more than seventy practical air conditioning systems in Japan. Several problems encountered in the application are 1) changing rate of concentrations of surfactant and counter ion during long term use, 2) some corrosion inhibitors and oils blocked the drag reduction, and so on. It is also necessary to develop more effective additives, especially could be ns were examined experimentally and a suitable additive condition, which could expand effective temperature range of drag reduction, is proposed.

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Turbulent drag reduction in Couette flow was investigated for aqueous solutions of a nonionic polymer, poly(ethylene oxide) (PEO), a cationic surfactant, hexadecyltrimethylammonium choride (HTAC), and their mixtures. Consistent with literature data, drag reduction was observed for PEO solutions above a critical molecular weight, 0.91x10⁵ < M_c < 3.04x10⁵. Maximum drag reduction occurs at an optimum concentration, c*_PEO, which scales inversely with molecular weight, and the %maximum drag reduction increased with molecular weight. For aqueous HTAC solutions, wall shear stress decreases with increasing HTAC concentration and levels off at an optimum concentration, c*_HTAC, comparable to the critical micelle concentration. For HTAC/PEO mixtures, the critical PEO molecular weight for drag reduction decreases, interpreted as due to an increase in hydrodynamic volume because of binding of HTAC micelles to PEO. Consistent with this interpretation, at fixed PEO concentration, maximum drag reduction is observed at an optimum HTAC concentration, c*_HTAC/PEO, comparable to the maximum binding concentration, MBC. The effect of ionic strength on surfactant solutions and polymer-surfactant complex solutions was also investigated. For HTAC in salt solutions, addition of salt decreases the optimum HTAC concentration, c*_HTAC, and the % maximum drag reduction decreases with increasing ionic strength. On the other hand, for the aqueous PEO-HTAC solution, the wall shear stresses upon addition of HTAC beyond the respective CMC values are strongly reduced as ionic strength increases.

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Fibers can be coated by passing them through a solution. In this paper, the thickness of the entrained film on the fiber was experimentally measured for various solutions such as water, polyacrylamide (PAA), and polyethylene glycol (PEG) aqueous solutions, and the effect of rheological properties of the solutions on the film thickness was studied. For low viscosity materials, such as water, the film thickness followed the Landau-Levich-Derjaguin (LLD) equation at low capillary number but, due to the inertial effect, it deviated away from the equation as the withdrawal velocity of fiber increased. The 3-D direct numerical simulation was performed to confirm the inertial effect on the entrained film thickness. For polymeric solution, the film-thickening rate against the capillary number was estimated by the LLD equation at low capillary number. However, the absolute value of the film thickness was far larger than that from the equation even when the withdrawal velocity was low. It could be considered the elongational deformation of polymer around fiber, which can be observed in the tubeless siphon phenomenon, affected the thickness of the polymeric film.

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The thin tapes are frequently used in modern applications to be filled with liquid into the void spaces among compacted particles. In the present study, the liquid penetration rate is measured for green and pressed tapes prepared under various cast parameters with graphite particles differing in original particle properties. In addition, an attempt is made to derive the penetration rate from the tape characteristics of porous micro-structure. The mathematical model of liquid penetration kinetics was developed, assuming the tape void space as the bundle of capillaries. The distribution of capillary diameters was defined as the distribution of void sizes measured by image analysis on the cross-section perpendicular to the tape surface. As a result, it was confirmed that the measured rate of liquid penetration into the tapes, which were prepared with various casting speeds, blade gaps and slurry concentrations, is mainly determined by the distribution of void sizes. The largest value of the penetration rate constant was obtained for the tape made of spherical particles followed by those manufactured with fibrous and flaky particles, as could be expected from the analysis of void size distributions. Penetration rates into layers of synthetic graphite particles were higher than in those made of natural particles possibly due to the difference in their contact angles.

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A novel microfluidic device was designed and fabricated to overcome size dependence of droplet on microchannel (MC) dimension with microchannels having three inlet channels. The microchannels have rectangular cross-section with a depth of about 5 micrometers. A viscous stream (i. e., the dispersed phase) flowed centrally between two inviscid streams (i. e., the continuous phase). Increasing the flow rate ratio of the side flow to the central flow (Fs / Fc) resulted in the reduction in the width of the central flow and flow instability. As the width of the central flow was narrowed down below a critical breakup width, the breakup of the viscous liquid sheet occurred and droplets with the diameters smaller than channel size were formed. The effect of channel configuration on the narrowing down and the breakup of the central flow is presented. With this microfluidic system, it is possible to observe real-time process of droplet formation and precisely control droplet size. This approach shows promise for the applications of such as microemulsification and precision fluid microdispersing.

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The office paper shredded into various sizes was used as a model substrate of waste paper in this work. The enzymatic hydrolysis of the office paper was carried out in an external airlift bubble column reactor equipped with an ultrasonic horn system with sparging the water saturated or unsaturated gas. The sparging gas humidity, substrate size and ultrasonic intensity were varied to examine their respective effects on the enzymatic reaction. The enhanced hydrolysis showing a two-stage time course was observed even with no ultrasonic irradiation in the airlift reactor when either unsaturated air or nitrogen was bubbled into the reaction suspension, while much less enhancement effect was observed when either saturated air or nitrogen was employed. The total sugar productivity with sparging either saturated air or nitrogen was lower than that in the case of sparging unsaturated gas. This was ascribed to a shear stress acting on the surface of office paper in the gas-sparging section in the riser in the same way as in the ultrasonic irradiation section in the stirred tank used previously. The critical superficial gas velocity for the complete substrate circulation was found to be reduced as the substrate size decreased. The smaller paper size required the lower critical gas velocity in addition to a more enhanced hydrolysis with a more remarkable two-stage time course. In the ultrasonic airlift reactor with sparging the saturated air, the continuous ultrasonic irradiation was also found to be effective for enhancing the enzymatic hydrolysis. The time courses observed were analyzed and simulated successfully based on the kinetic model proposed previously. The variation in the paper sizes, sparging gas humidity and ultrasonic irradiation exerted an effect on the apparent rate constant and ultimate total sugar concentration, but no effect on the apparent Michaelis and competitive inhibition constants.

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The ultrasonic computed tomography (UCT) as a combination of the ultrasonic sensor and the tomographic reconstruction technique based on the filtered back-projection (FBP) was applied to investigate the cross-sectional distributions of gas holdups in a 16 cm diameter bubble column. The gas-liquid dispersion system of air-water was used. Measurements of gas holdups obtained by using UCT are compared with those obtained by bed expansion method. Generally, the trends of UCT measurement are correct but the agreement remains qualitative.

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Both rigid and non-rigid particles were used to investigate the axial size segregation in a rotating drum. The effects of the rotational speed, the fill level, and the particle size ratio were evaluated. When rigid glass particles with diameters 0.35 mm or 0.70 mm were mixed with large particles with a size ratio 2, 3, or 4, the width of the segregation band was not affected by the rotational speed at levels of fills of 30% and 40%. There exists a size ratio where the dimensionless band width has a minimum value. The value is approximately 3. The existence of this value was attributed to the diffusion and inertia mechanisms of the motion of a single particle. The dimensionless band width is a function of the rotational speed when 1 mm rigid glass particles are mixed with 2 mm rigid glass beads.
A comparison was made on the influence of the fill level on the dimensionless band width using both rigid and non-rigid particles. Rigid and non-rigid particles show difference dependence on the level of fill. The dimensionless band width increases with the increase of the level of fill using non-rigid rubber particles (1 mm: 2 mm) at all rotational speeds. Whereas the dimensionless band width decreases with the increase of the level of fill when rigid glass particles (1 mm: 2 mm) are used at all rotational speeds.

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Experimental and theoretical studies have been conducted on the control of the particle size distribution and the crystallinity of the product powder in a closed-circuit pulverization system. The performances of a pulverizer and a classifier were modeled by the experimental data. By use of these performances, the particle size distribution of the product powder was simulated numerically by an iterative method. The change in the crystallinity of the product powder was also simulated, based on the two hypotheses. Namely, one is that the crystallinity of the product powder is determined by the pulverization times, another is that the crystallinity is determined by the particle size distribution.
The product powders, which have the same mass median diameter, have different crystallinity, when the closed-circuit pulverization system is operated with the different conditions. It is found that the product which has relatively low crystllinity can be obtained, when the rotational speed of pulverizer is high. This is why the pulverizer reduce the particle size with inhibiting the breakage of the crystal structure in the case of the lower rotational speed. Furthermore, in the closed-circuit pulverization system, it takes longer time to attain the steady state of the product properties, when the rotational speed of pulverizer is lower.
We can successfully simulate the change in the flow rate, particle size distribution of product powder with elapsed time. On the other hand, the change in the crystallinity of the product powder can be expressed by the simulation based on the latter assumption. But the crystallinity difference of the steady state can be simulated by not this simulation but the simulation based on the former assumption. Therefore, this fact suggests that the crystallinity of the product powder is determined by both the particle size distribution and the pulverization times.

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Discrete particle simulation has been extensively used in the laboratory of particulate and multiphase processing at the University of New South Wales (UNSW) to study the fundamentals of particulate matter at a particle scale. This paper briefly reviews the work in the laboratory, which covers the development of simulation techniques and their application to the study of typical static or dynamic particulate systems including particle packing, sandpiling, particle flow in bladed mixer, rotating drum and hopper, gas-solid flow in packed and fluidized beds. Emphasis is given to the validity analysis of the simulation method and the usefulness of the resulting particle scale information in elucidating the underlying physics.

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Co-grinding nonferrous metal (Cu, Pb, Cd, and Zn) oxides with sulphur (S) in the presence of a reducer such as iron (Fe) powder was conducted to stimulate their solid-state reactions, forming nonferrous metal sulphides in the product. The co-grinding induces the sulphidizing reaction and the yield is improved with an increase in grinding periods of time. Any hazardous gaseous substances are not generated during the grinding. The Fe plays a significant role to reduce the metal oxides, and it has been oxidized to form magnetite (Fe₃O₄). The necessary conditions to sulphidize the oxides have been clarified based on the thermodynamic discussion. Separation of the sulphidized materials from the product can be achieved by flotation, when it is suspended in water. In the present stage, we have intensively conducted a feasibility study to recover the nonferrous metals from a combustion dust or its relevant wastes emitted from an incineration facilities. This process could be also applicable to remove heavy metals such as lead (Pb), cadmium (Cd) from their contaminated wastes.

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Toxic species such as dioxins and heavy metals released from incinerators have become a serious issue that Japan has been confronted with. Since they are concentrated especially in fly ash, supplemental treatment systems to detoxificate them are usually required. If the regulation of these species shifts to that by total emission in future, they will need to be removed from fly ash by some method such as thermal treatment and chemical extraction. The present study was aimed at establishing a technique to treat these species (dioxins, zinc and lead) in fly ash at a high temperature (>500 oC) by adding chemicals while preventing the sintering of fly ash. Based on the hypothesis that calcium chloride in fly ash results in the sintering, sodium hydroxide (NaOH), mullite and coal fly ash were chosen as additives to scavenge chlorine from fly ash. The fly ash samples with additive were heated up to a given temperature (400 to 1000 oC) for a given time, followed by various analyses for the determination of chemical and physical structure of the treated fly ash as well as the quantification of the volatilized heavy metals and the remaining dioxins. As a result, we found that CaClOH plays a key role in the sintering, and that the additives studied in this work are effective for the decomposition of CaClOH so as to suppress the sintering of treated fly ash, and these other than NaOH enhanced dioxins decomposition and heavy metal volatilization from fly ash.

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In order to design and control a release pattern of active component, the release characteristics were investigated for the particles coated with multiple layers of fine soluble and permeable particles dispersed in the impermeable wax. The effect of the operational conditions was examined on parameters of the release profile by multivariate analysis. The simplified correlations were obtained for the maximum release rate by the slope and the lag time of the release curve as a function of the volume fraction of permeable particles and the thickness of the permeable- and soluble-particle layers. As a result, it was confirmed that the desired release rate could be obtained in the first place by adjusting the volume fraction and thickness of the permeable-particle layer. Then the required lag time might be attained by changing the thickness of the soluble layer. Finally, the possibility to design the controlled-release particles with the prescribed sigmoidal release pattern was successfully illustrated by the calculation example.

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For CO₂ capture at high temperature/high CO₂ partial pressure conditions, a new dry CO₂ removal sorbent was developed. The CO₂ sorbent particles were made from fine particles of lithium silicate and granulated using a tumbling fluidized bed and then coated by a layer of coarse alumina particles with a ceramic sol solution binder. The minimum fluidization velocity and adsorption/desorption properties of the sorbent particles were determined in a laboratory scale fluidized bed reactor (i.d.,0.03m) in the temperature range between 873K to 1073K. The characteristics of particle component, sphericity, and breaking behaviors were correlated with particle fluidizing behaviors. An overall conversion yield of 50% and maximum adsorption capacity of 10wt% for the sorbent particles were obtained after a 60 cycle adsorption/desorption test.

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Experimental and theoretical studies have been conducted about the cut size control with revised dry cyclone. New type of dry cyclone with the apex cone which is covered with special shaped ring indicated cut size movement from 2 to 40µm. Regarding the movement of cut size by blow-up method, the cut size is related to the degree of incoming fluid volume inside the dust box. By use of the apex cone at the inlet of dust box, it is possible to decrease the fluid velocity component in the dust box and to reduce the re-entrainment of particles from the dust box. The cut size indicates the minimum value for the specific height of the apex cone. The optimum apex cone height changes to the lower position as the cyclone inlet velocity increases. The experimental data agreed with the numerical simulation based on the direct flow calculation method. Classification performance of revised cyclone with the use of additional fluid in a upper cylindrical part are also examined. By selecting a special part of additional flow position, it is possible to reduce the cut size with the increase of additional flow rate. Three dimensional numerical simulation were also conducted and compared with the experimental data.

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A supersonic virtual impactor with a Laval nozzle was numerically investigated into its performance as a separator or concentrator for ultra-fine aerosol particles down to nano-size range. Influences of the impactor geometry, such as shape of nozzle cross-section (rectangular and circular), clearance between nozzle exit and particle collection probe inlet, and probe geometry on the separation characteristics were numerically investigated. The effect of sheath flow along the nozzle wall and center was investigated into its effect on the separation characteristics and the particle wall loss.
The supersonic virtual impactor was designed to obtain the stagnation flow, which provided a distinct standing shock wave between the nozzle exit and the collection probe inlet. The smaller distance from the collection probe inlet to the standing shock wave was related to the cutoff size of particle. The sheath air flow improved the separation sharpness and the particle wall loss.

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The movement of spherical particles in a twin roller system for size classification has been studied experimentally. The diameter of the particles used is 600µm. The classification system consists of a feeder, a twin roller unit and containers for collecting particles classified. The two rollers can be set at a desired angle from the horizon. The rollers can be rotated at an arbitrary angular velocity. All the particles that are fed from the feeder move along the gap between the two rollers. As the gap width increases downward, the particles fall down at a point where the gap width exceeds the particle diameter and are collected in containers arranged in a row. The motion of the particles moving along the gap is observed through a high-speed camera connected with a microscope. The image analysis shows that the particles roll down with small jumping, and the rotation of the particles depends on the operating condition of the twin roller system. The particle velocity along the gap varies according to the jumping. The flight time, normal velocity, and distance can be calculated from the velocity difference of the particles before and after the contact with the rollers.

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In this research work, mixing of granular flow has been investigated inside a sectorial shaped container subjected to sinusoidal oscillations. A sectorial container containing particles is oscillated in the range of 1Hz to 4Hz. Effect of different operating parameters such as frequency of oscillations; amplitude of oscillations, volume fraction and the size ratio of particles is studied. It is seen that the simulated flow characteristics of both unary and binary granular beds in the oscillating sectorial containers have similarities with those of the particulate beds subjected to combined vertical and horizontal vibrations in that the granular bed heaps toward one of the container walls. The flow behavior and the motion of particles is confined in a two-dimensional transverse planes to make a better comparison with the numerical simulations. It is also found that the mixing and segregation of particles takes place in a particular range of frequency zone. A range of frequency is identified for active and stagnant heaping of particulates. Good mixing is observed above and below a certain frequency range. Critical frequency region is also identified where the particulate matter is symmetrical to the shape of the container and asymmetrical heaping is observed above and below this critical frequency range. Effect of initial arrangement of layers of different particulates is also studied. Snapshots of experimental observations are compared with the numerically simulated characteristics. Numerical modeling using discrete element method has been carried out to validate the experimental observations. Mixing that takes place in different regimes is quantified by estimating the degree of mixing and a mixing rate constant. Granular temperature of the system for different set of frequencies is estimated which clearly shows the difference in energy levels for a segregated and well-mixed system of particulates. Overall, a good agreement is found between the experimental observations and numerical simulations.

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The gas-slurry-solid fluidized bed is a unique operation where the upward flow of a liquid-solid suspension contacts with the concurrent up-flow of a gas, supporting a bed of coarser particles in a fluidized state. In the present study we measured the gas holdup, the coarse particle holdup, the cylinder-to-liquid mass transfer coefficient, and the cylinder-to-slurry heat transfer coefficient for controlled slurry concentrations. The slurry particles were sieved glass beads of 0.1 mm average diameter and their volumetric fraction was varied at 0, 0.01, 0.05 or 0.1. The slurry and the gas velocities were varied up to about 12 and 15 cm/s, respectively. The coarse particles fluidized were sieved glass beads of average diameters of 3.6 and 5.2 mm. The phase holdup values for the gas, slurry, and coarse particles were separated on the basis of the measured properties including axial static pressure distribution, axial distribution of the liquid holdup evaluated from an electro conductivity method and the bed height. The gas holdup values were correlated by a dimensionless equation, and the solid holdups (voidages) were well correlated by modifying an empirical model proposed by Hirata et al. (1995) for the viodage of the three-phase fluidized beds. The heat transfer coefficient and the mass transfer coefficient can be correlated well by a unified correlation in terms of the specific power group, including the energy dissipation rate per unit mass of slurry with small deviations between the calculated and experimental data values for both the mass and heat transfer coefficients.

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Particulate bed expansion and its collapse were investigated for binary powder-particle mixtures of FCC particles (Geldart A) and a small amount of cohesive Al(OH)₃ powders (Geldart C) up to 15 ?m in mean size with starting fractions of fine powders in the bed no larger than 5 wt%. The column of a fluidized bed was a transparent vinyl chloride column of 0.104 m i.d. with a porous metal-sintered distributor. Superficial gas velocities at incipient fluidization and bubbling were also investigated. The effects of size and hold-up of fine powder on the particulate bed expansion and its collapse were investigated.
When the hold-up of fine powder in the bed was less than the maximum value (1wt% for 1-?m fines and 3wt% for 3-µm fines) to avoid segregation or aggregation during fluidization, bed expansion as well as de-aeration rate increased with increasing the hold-up of fine powders. Thus, the difference between superficial gas velocities at incipient fluidization and bubbling got larger with increasing the hold-up of fine powder in the bed. When the size of Al(OH)₃ powder was 1µm, a small hold-up of fine powder such as 1 wt% was still effective to increase the minimum bubbling velocity and the dense phase expansion as compared to FCC particles alone.

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Fluidization is a key technology for nanoparticle handling and processing. Nanoparticles can be fluidized with forming agglomerates due to large interparticle forces. Fluidization characteristics such as bed expansion, solids volume fraction along height, and segregation in a fluidized bed are studied using three kinds of nanoparticle titanium oxides. Agglomerates formed in the bed is so hard that they are not destroyed during fluidization in cases of 7 and 20 nm particle system while bed expansion takes place. The solids volume fraction in a freeboard is increased with increasing gas velocity especially in the case of 7 nm particle system. The segregation of agglomerate takes place for all particle cases. Agglomerate size obtained from umfa tends to be larger than the volumetric average size observed. It is thought the gap between them is attributable to the gas entered inside the agglomerate.

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Recently, a rotating fluidized bed has attracted special interests, since it can fluidize very fine particles uniformly. In this study, handling of nano-particles has been attempted by using a novel rotating fluidized bed, which is basically consists of a plenum chamber and a horizontal porous cylindrical air distributor that rotates around its axis of symmetry inside the chamber. First of all, fluidization behaviors of nano-particles having their sizes between 10-20 nano-meters were investigated. The pressure drop, minimum fluidization velocities and bed expansion were measured under various centrifugal accelerations caused by the vessel rotation. The results indicated that nano-particles could be fluidized uniformly in a rotating fluidized bed. The mixing characteristics of nano-particles have also been investigated under various mixing times and centrifugal accelerations.

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A systematic investigation on particle elutriation conducted in a vortexing fluidized bed cold model, 0.19m in diameter and 4.0m in height, is reported. Glassed beads were used as the fluidized material. The coarse particle diameter was 545µm. The fine particles used for elutriation were 81, 97, 113μm in diameter. The effects of various parameters on the elutriation are investigated fro the data obtained using the response surface methodology (RSM), which provides an efficient experimental strategy.According to the information obtained from previous studies, the dominant factors for elutriation rate are known as gas, particle and fluid dynamics characteristics within the fluidized bed. Therefore, the primary and secondary air flow rates, secondary air injecting nozzle diameter, imaginary secondary air and fine particles were chosen as the operating parameters.
The experimental results showed that the significant dominant factors order was: the primary-air flow rate, fine particle size, secondary-air flow rate, imaginary circle diameter, The primary air interactions with the fine particle size, secondary-air flow rate with the imaginary circle diameter, and secondary-air flow rate with the secondary-air inlet diameter exerted significant influences on the elutriation behavior.

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Plug flow fluidized bed can be applied for continuous operation of rough rice drying. Novel fluidized bed technology enables drying of rough rice and dedusting / dehusking to be carried out simultaneously in plug flow fluidized bed. This paper reports the study of the effect of superficial gas velocity and inclination angle of distributor plate on rough rice flowability in inclined distributor plate plug flow fluidized bed as well as the efficiency of dedusting / dehusking. Experimental works had been carried out using rough rice (Group D particles) in a 2.5m height inclined fluidized bed column of cross sectional of 0.61m x 0.15m. The result showed superficial gas velocity has to be exceeds rough rice's minimum fluidization velocity (at least 1.55 u_mf for the case of rough rice) in order to ensure a smooth flow of rough rice on the inclined plate. At superficial gas velocity lower than minimum fluidization velocity, particles flow was not consistent. The bed of rough rice started to flow only when the effective weight of the bed of rough on inclined distributor overcomes the total friction between particles and particle-surface. On the other hand, dedusting / dehusking separation efficiency at low superficial gas velocity (approximately 1u_mf) gave unsatisfactory separation of merely 40% of rice husk. At higher superficial gas velocity at 1.5u_mf, separation efficiency of rice husk as high as 93% was achieved. In addition, higher distributor inclination angle gave slightly improved separation efficiency.

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Low temperature gasification using GLO (Gasification using Lattice Oxygen) was investigated based on the Chemical Looping Combustion or MERIT(MEdiator Recirculation Integrating Technology) reaction system utilizing the lattice oxygen of metal oxide coated on porous particles to oxidize organic compounds for effective solid fuel conversion. Pyrolysis and steam gasification were tested in a single column reactor in which the flow of the gasification agent and the air were switched to change the gasification and the oxidation (combustion) under the temperature range from 723 K to 973 K. Generated gas composition was analyzed by micro gas chromatography. Deposited and unreacted carbon were combusted with low oxygen concentration air; 5-13% -O₂ simulating exhaust of conventional combustor and gas turbine. Hydrogen was a major product and methane, CO and CO₂ were minor products in this system. No wax and tar were observed in the exhaust line while a certain amount of wax and tar were observed in the experiment without metal oxide. When steam was supplied, hydrogen yield became 3 for 1 moles of carbon at 773K. As a result of the experiments, GLO system has possibilities for the low temperature gasification.

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Nucleation, 'birth of the new phase', is the first step in the crystallization process, followed by crystal growth, which is the growth of existing crystals to larger sizes. The control and study of nucleation processes are difficult and the impact of nucleation on polymorphism is not well understood. In this review, novel methods to study and control crystal nucleation including non-photochemical laser-induced nucleation, templated-crystallization on functionalized surfaces and the use of electrodynamic levitation will be discussed. It is essential to understand and control nucleation as it is the key aspect in tailoring the crystal size and shape, and controlling the crystalline form.

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Polymorphs is getting to be increasingly important problems in pharmaceutical industries, because the bioavailability and some other properties depend on each polymorph. Therefore, the control of the crystallization including polymorphs is very important. As a crystallization method anti-solvents are frequently used in pharmaceutical industries. In this crystallization the solvent compositions change with time. At the same time the various operational factors also influence on the polymorphic crystallization behavior including transformation. However, the quantitative details of crystallization behavior and the mechanism of the anti-solvent crystallization has not been known. In this study the thermodynamic stability,the transformation and the crystallization behavior of the polymorphs of the thiazole-derivative (BPT), which is one of the pharmaceuticals, were investigated in methanol-water mixture solvents at 323K. BPT has three polymorphs (A, B and C) and two solvated crystals (BH and D). The thermodynamic stability of crystals and the transformation behaviors are complicated. Such behaviors were related with the temperature and the solvent compositions.
The crystallization was also carried out by adding water which is an anti-solvent for BPT to the solutions. It cleared that at 323 K only the meta-stable form crystallizes and the crystallization behavior depends on the initial concentration of the solute and the addition rate of water. At low initial concentrations, BH crystallized independently of the addition rate of water. However, at higher initial concentrations, the D form crystallized in addition to the BH form, especially at low water-addition rates. It was also found that the crystallized form transform to several different forms, and the transformation characteristics are dependant upon the initial concentration of BPT.

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In industrial crystallization, control of crystal morphologies becomes a very important subject. For organic compounds, each face has a different growth mechanism and a growth rate because they have different orientation of molecules. Therefore, growth rates of particular faces are controlled by noncrystallizing components. However morphology control by noncrystallizing components were not enough to be understood. This paper described the influence of p-CNB on the m-CNB crystal as relationships between the additive concentration and the supercooling, and the dynamic behavior of the crystal morphology when the supercooling was stepwise changed. The m-CNB crystal has the round face on +z direction under the presence of p-CNB. Form the experimental results the crystal morphology depended on not only the additive concentration but also the supercooling. When the supercooling was changed from the condition that the rounded face appeared to the condition that it did not appear, the rounded face disappeared slowly and there was a time period that the maximum length of +z direction was not changed. The driving force of the crystals growth was used for the repair of the rough face. In the region that the rounded face appeared, it was observed that the maximum length of +z direction decreased temporarily after the change of supercooling. From these results, new knowledge of the influence of noncrystallizing component on crystal morphology was obtained.

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A full understanding of growth rate dispersion (GRD), whereby seemingly identical crystals grow at different rates under identical conditions, has not yet been achieved despite thirty years of research into the phenomenon. The current study investigated the effect of a crystal's 'growth rate history' on the current crystal growth of sucrose, potash alum and KDP crystals. All three crystals, which differ in terms of crystal structures and thermodynamic properties, had similar results showing that the growth history of a crystal had a significant effect on the future crystal growth rate of that crystal. In particular, if a crystal had a period of high growth in a high supersaturation environment, the subsequent growth of the crystal in a lower supersaturation had a lower rate than a crystal that had been kept in the lower supersaturation environment. These results can be explained by the effect of high growth rates on the growing surface of a crystal. It was observed that crystals grown in high supersaturation solutions had a rougher surface (on a macroscopic rather than molecular scale) than those grown in low supersaturation solutions. This phenomenon only occurs if growth occurs above a critical level of the supersaturation, that we term the roughening transition. The roughening transition supersaturation for a crystalline species depends on the surface energy of the crystal, with species having a relatively large surface energy having a low roughening transition threshold. This situation could be quite important during either nucleation or growth periods. The initial nuclei form at a higher supersaturation than later nuclei, and this may relate to differences in initial growth rates for apparently identical nuclei. In addition, if local levels of supersaturation vary, there will be an effect on the inherent crystal growth rate dispersion, in addition to random fluctuations in growth rate.

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The simultaneous optical resolution by cooling crystallization using seed crystals of different two size groups was examined. It was proved as a useful method of optical resolution by crystallization. In this study, DL-asparagine (Asn) was used as a model substance. Seeded cooling crystallization was performed with the L-Asn seeds of large size and the D-Asn seeds of small size. Both seeds were added enough over the critical seed loading ratio, which was determined for a given seed size by using a correlation proposed previously for non-chiral systems (Doki, et al. 2002). The product crystals obtained had bi-modal distribution without fines. The large crystals were L-Asn of 100% purity and the small crystals were D-Asn of 100% purity. These results suggested that nucleation was suppressed by the addition of seeds and the crystallization was dominated by the growth of seed crystals. The size difference between the L- and D-products was also controllable. The optical resolution was accomplished by subsequent mechanical classification of crystals after crystallization. The simultaneous optical resolution was also examined for the case of insufficient seeding. In this case, fines removal by a dissolving circuit attached to the crystallizer was effective for perfect optical resolution. Further, the phenomena were discussed quantitatively in detail.

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