In wastewater treatment, an emulsion polymer automatic dissolving system is used to mix and dissolve the polymer used as a polymer coagulant with water before it is put into the dissolution tank. In this study, a disperser is developed to mix water and emulsion polymer better in the dissolving system. For this purpose, the flow analysis of the three disperser models was performed to select the disperser for the emulsion polymer automatic dissolving system with the best performance. The excellence of mixing was evaluated by grasping the flow uniformity and the vorticit in the disperser, and it was confirmed that the TYPE3 disperser was excellent.

This research was conducted for dewatered sludge cake of industrial wastewater treatment, i.e., as the object of inorganic sludge discharged especially in iron & steel manufacturing shop which used Air drying system to reduce water content. That drying system's single-type cyclone separator was confirmed to have significantly lower separation efficiency on the conditions 20μm and below of particular size through computational fluid dynamics(CFD) analysis. However, we found out the primarily advanced value of separation efficiency on dual-type directly connected. Regarding separation efficiency on size of 10μm, the efficiency of a single-type was presented at 51.91%. On the other side, the efficiency of the dual-type was 97.88%. This advanced effect of the dual cyclone separator was checked at a demo facility of air drying equipment designed by 340m3/min of airflow on site.

It is necessary to develop a device for the design of wet scrubber with a more efficient deodorization performance in order to enhance the odor reducing effect of the wet scrubber. Therefore in this study, the superiority of the new wet scrubber with the centrifugal separation function different from the conventional wet scrubber was analyzed by the computational fluid dynamics. From CFD analysis, the pressure and velocity distribution, the peak vorticity, the retention time and the flow uniformity were calculated and compared with the performance characteristics of the centrifugal separator. As the results of CFD analysis, the peak vorticity and retention time of the gas flow were increased about 22% and the flow uniformity was improved about 7.2% by the centrifugal separator. Therefore the centrifugal separator in the wet scrubber will improve the deodorizing effect and the cleaning condition of the gas.

The objective of this study is to evaluate the structural safety of the spherical-helical turbine for hydro-power. We analyze fluid-structure interaction of the spherical-helical turbine for hydro-power using ANSYS-CFX and Mechanical. The maximum combined stress, deformation and safety factor of the spherical-helical turbine in cases of three types of materials were obtained by fluid-structural analysis. From structural analysis, the maximum value of the equivalent stress occurred at the shaft of the turbine for three material types. In case of a polyethylene turbine blades, the maximum equivalent stress and safety factor were 3.46 MPa and 7.23. Polyethylene turbine blades were evaluated to be safe except of the turbine shaft. Several researches will be performed based on the results of this study and more research and development of technologies are needed in this field.

This is to develop a micro water turbine which makes some power from just a fluid velocity in the water pipe. While power is produced from impulsive force which generated by a high head in the case of existing water turbine, this is to produce a power from rotating force of helical turbine which rotated by fluid velocity in the water pipe. Some results of analysis fluid pattern at turbine blade for design shows that bubble is generated from turbulence surrounding blade and pulsatory motion generated as fluid being blocked and opened by blade due to turbine structure. This two phenomena cause to lower power production efficiency and shorten turbine durability. So this is studied to minimize bubble generation and pulsation for optimizing design of turbine blade. Therefore it is determined that the number of blade is three, geometric form of blade is NACA 4420 and angle of blade is 30 degree. An experiment equipment of water turbine is manufactured on the base of these factors(NACA 4420, angle 30。). It is obtained that power production of turbine increases in proportion to velocity which is changed from 1.7 m/sec to 3.5 m/sec. When fluid velocity is 1.7m/sec the power production of turbine is 355W. Power production increase continuously as increasing the fluid velocity and power is 2kW on 3m/sec of fluid velocity.