This study was conducted to investigate the removal characteristics of PO4 3- -P contained in livestock wastewater using waste concrete. With small particle size, increased dosage and temperature of water, PO4 3- -P was well removed by waste concrete. PO4 3- -P was removed by adsorption reaction in low pH of the primary phase, but the crystallization reaction predominated for increasing pH with passed time. As a result of adapting the adsorption isotherm equation, PO4 3- -P removal was more affected by the crystallization reaction than the adsorption reaction. In the SEM micrograph, there was no evident change on the waste concrete surface. Particle size was plate-phase before reaction but appeared a dense form to progress in the crystallization reaction after reaction.

A two dimensional numerical model as well as theoretical formula are used to investigate the seich characteristics of Mok-po harbour. The natural periods of the first two modes computed from the numerical mode are about 34 minutes and 12 minutes which are well consistent with those by the theoretical formula.