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Fluoride(F-) is present in wastewater produced by various industries, such as semiconductor, glass processing, mining and smelting. Development of high-efficient and low-cost treatment processes of wastewater is desirable. In this study, Seashells sorbents for F- removal were synthesized by phosphate solution treatment of seashells (oyster, scallop, sea urchin and barnacle) waste at room temperature. The seashells sorbents could remove F- in water to below effluent standard (8 mg/L) in Japan. The optimal initial pH range for seashells sorbents synthesis was below pH6. The phosphate consumptions for synthesis could be estimated by specific surface area of seashells. F- sorption isotherms of seashells sorbents were fitted well by the Langmuir model. The synthesis reaction of seashell sorbents at room temperature was that calcium hydrogen phosphate was produced to the surface of calcium carbonate contained in seashells. Dominant mechanism of F- removal of seashell sorption was identified as to form fluorapatite from the calcium hydrogen phosphate and F-.

Generation of new concepts in product design process serves as driving force of innovation. While many methods have been proposed for supporting design concept generation, it has rarely been supported in a systematic way, because its process is done in designer's implicit thought, and therefore, it is difficult to explicitly formalize the process. This paper proposes a model of designers' thinking process in concept generation called ECF cycle. It consists of three steps, i.e., (1) Externalization: the step for representing design concepts with drawings and language, (2) Classification: the step for classifying concepts with function trees, and (3) Finding voids: the step for finding potentials of new concepts called void, which is a defect of the classification. Then, this research builds a new method of concept generation incorporating the theory of solving inventive problems (TRIZ). The method is based on a quick reference table of TRIZ principles, which helps designers to create a new concept corresponding to a void found by ECF cycle. A case study of concept generation of new running shoes is demonstrated in order to verify the ability of the proposed method.