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The historical turning point we are now facing is the biggest since the Industrial Revolution. For sustainable social metabolic system development, a transformative change in industrial processes and systems as well as our lifestyles is required. A firm cornerstone for a constructive life, a clear perspective for science and technology, and open mindedness will help us to tackle the big issue of a transformative redesign of our society. Furthermore, for effective change from centralized to decentralized energy systems, it is necessary to empower regional communities. This article presents six features concerning the above issues that are methodologically valuable for researchers and engineers. [ABSTRACT FROM AUTHOR]

The environmental and resource crises that confront human life on earth demand changes to the whole socio‐economic metabolic system. The changes will affect all aspects of life, including the practice of chemical engineering. The historical association of the profession with the fossil carbon economy means that the expertise that makes up chemical engineering must be re‐examined and repurposed urgently if the discipline is to play a full role in the socio‐economic transition. In this article, we review the historical development of chemical engineering to identify its unique features and find ways in which it can change to meet the challenge. A pattern of 30‐year cycles in the development of the discipline is revealed, showing the way it has built up by incorporating approaches from other disciplines and also developing a unique set of skills and knowledge. Chemical engineering as taught needs to prepare graduates to operate under the kind of social contract embodied in declarations by professional bodies. We propose ways in which the expertise comprising chemical engineering can be applied in the 'just transition' to a less unsustainable society, including new approaches to plant and process design and also applications 'outside the pipe' to environmental modelling and industrial ecology. The unsustainability crisis results from a history of poor public and private decisions, so examination of the different types of decisions is timely. Specific roles for chemical engineers in deliberative decision processes are identified, including enhanced emphasis on risk and precaution. [ABSTRACT FROM AUTHOR]

For the process intensification of ferrite production, fluidized bed calcination of raw‐mix (RM) particles for strontium ferrite was tested in a laboratory scale fluidized bed. In cases when the bed was made only of RM particles, agglomeration took place above 900 K, and above 1350 K rapid defluidization was unavoidable. However, successful calcination with no defluidization was achieved by calcining RM particles in the bed of coarse spherical alumina particles. One kilogram of calcined product was produced by repeated batch calcination at 1423 K and with retention time of 60 minutes. The products were made into magnets and their magnetic properties were evaluated. The magnetic properties of fluidized bed product were compatible with rotary kiln products, although residue of unreacted Fe2O3 seemed to have detracted the former somewhat. The presence of unreacted Fe2O3 was found to be caused by the selective adhesion of SrCO3 on the bed material. A slight adjustment of Fe/Sr ratio in the RM was found to be effective in the elimination of such residuals. [ABSTRACT FROM AUTHOR]

For the utilization of renewable energy from sources widely distributed in low-density non-urban areas the grid augmentation for its transmission to urban areas of high population density is often discussed under the premise that the present demand distribution remains invariant. Instead of grid augmentation, this study examined an alternative option of creating a power demand close to renewable sources and inducing population movements (i.e., Renewable Energy Exodus). First, the capacity of renewable energy to maintain populations in hilly and mountainous farming areas of Japan was evaluated from two perspectives: Task (1) a challenging nationwide balance based on possible energy demand saving scenario for the future, and Task (2) a conservative nationwide balance based on the current per capita energy demand and on the region-by-region generation–consumption matching concept. Because Task (2) indicated that Hokkaido, the northern-most island, has a huge capacity, Task (3) was conducted for Hokkaido by examining both energy balance and economic evaluation including job creation for the following two scenarios: (A) a supply to Tokyo scenario and (B) a local demand generation scenario, keeping the same conservativeness as Task (2) by using the current data for energy consumption per capita. The nationwide Renewable Energy Exodus estimates gave 48 million people for Task (1) (with the future per capita energy demand) and 10 million people for Task (2) (with the current per capita energy demand and region-by-region self-sustained balance), respectively. For Hokkaido Task (3) (with an additional economic assessment) gave 1 million people. The Renewable Energy Exodus concept combined with the green economy promotion was found to have a significant merit for a sustainable future of countries like Japan where economic and social disparities are serious between urban areas and non-urban areas. [ABSTRACT FROM AUTHOR]

In many Japanese cities, a significant amount of CO 2 is emitted by private vehicles since modern lifestyles are highly reliant on them. In order to develop low-carbon cities, the establishment of a sustainable mobility system is essential. Meanwhile, local cities are facing a serious decline in social vitality, due to rapid ageing and economic deterioration. This paper examines a new approach for local city revitalization by introducing a “low-speed electric community bus” as a low-carbon transportation system. The bus was developed by the university–government, –industry, –education board, and –NPO collaborations. The test project was conducted in Kiryu city of Gunma prefecture as one of the projects of the JST-RISTEX's environment-energy program. In this paper, we report the co-design and co-development of a “low-speed electric community bus” for the establishment of low-carbon transportation systems. [ABSTRACT FROM AUTHOR]

To break the ‘carbon lock-in’ mindset adopted by policy makers, the potential for mass rural remigration, as an alternative to the current trend of moving from rural to urban areas was examined. The capacity of renewable energy to maintain populations in hilly and mountainous farming regions was evaluated from two perspectives: (1) an average nationwide estimate based on the future energy demand, and (2) a conservative estimate based on the current energy demand. Because estimate (2) indicated that Hokkaido has a huge capacity, a preliminary cost effectiveness analysis was conducted first for: (A) a Supply to Tokyo scenario, and second for (B) a Local Demand Generation scenario. Both renewable energy exodus scenarios were found to have merit in promoting a sustainable future. [ABSTRACT FROM AUTHOR]

Bearing in mind the co-evolution nature of transition to a sustainable low carbon system, in this paper, we define a new “co-evolution approach” and implemented it as an R&D funding program of JST-RISTEX. Through the examination of R&D project results, we found that our socio-technological co-evolution approach is effective for involving both academia and local stakeholders at the early stage of scenario building (co-design) and motivating them to commit sustainable local actions together (co-production). This approach initiated by our R&D program is a valuable endeavor implemented even ahead of the “Future Earth” international research initiative for sustainability under the International Council for Science (ICSU). [ABSTRACT FROM AUTHOR]

Abstract: In the present work, a novel cartridge type powder feeder is developed by applying ‘subliminal fluidization’, which is defined as partial aeration to the bed below minimum fluidization, but only for a limited region above the distributor, and by discharging solids together with the air through the tube located at the centre of the distributor. The distinct advantage of cartridge type feeder developed in this work lies in its simplicity of construction and operation giving quite an advantage for particulate material handling, transportation and metric feeding. Temporal solid efflux rates were measured for charcoal of mean sizes 220, 290 and 430 μm, glass beads of 265, 535 and 930 μm and spherical activated alumina (Neo beads) of 145 and 595 μm and density in the range of 1250 to 2500 kg/m3. Temporal flow rates of solids indicated that the solids efflux was independent of time and amount of material inside the bed and was only determined by the air supply from the distributor plate. Solids efflux rate was found to decrease with increased particle size and internal friction and reduced fluidization air flow rate. Solids efflux was found to vary slightly with the change in air humidity. A dimensionless correlation for solids efflux was developed as a function of fluidization number and the internal friction angle. [Copyright &y& Elsevier]

The effect of steam gasification conditions on products properties was investigated in a bubbling fluidized bed reactor, using larch wood as the starting material. For bed material effect, calcined limestone and calcined waste concrete gave high content of H2 and CO2, while silica sand provided the high content of CO. At 650°C, calcined limestone proved to be most effective for tar adsorption and showed high ability to adsorb CO2 in bed. At 750°C it could not capture CO2 but still gave the highest cold gas efficiency (% LHV) of 79.61%. Steam gasification gave higher amount of gas product and higher H2/CO ratio than those obtained with N2 pyrolysis. The combined use of calcined limestone and calcined waste concrete with equal proportion contributed relatively the same gas composition, gas yield and cold gas efficiency as those of calcined limestone, but showed less attrition, sintering, and agglomeration propensities similar to the use of calcined waste concrete alone. [Copyright &y& Elsevier]

The potential importance of surface cohesion effects in a polyolefin reactor was demonstrated by DEM (discrete element method) simulation. Searching for a more realistic particle-to-particle interaction, for more realistic DEM simulation the force-deformation characteristics were measured for the laboratory synthesized polypropylene (PP) particles. [ABSTRACT FROM AUTHOR]