Materials Science Forum Vol. 695

Abstract: Waternode station is a floating composite water quality monitoring device. The waternode station houses the multiple water quality measurement devices, control panel for wireless communication and solar cells for applying electric power. The floating devices are classified into general model with vertical dropping system and river model without vertical dropping system. The water quality measurement device measures pH, water temperature, conductivity, dissolved oxygen, turbidity and nitrate. And it measures all parameters simultaneously. The control panel is used for IP-USN system. USN (Ubiquitous Sensor Network) is a network system by water quality measurement devices. IP-USN is a USN system that identifies particular sensor connected to the internet. The data information is transferred by wireless modem based on TFB (Triple Frequency Band). Field application results showed that the waternode station is a reliable and cost-effective water quality monitoring solutions.

Abstract: Metal elements or other constituents transported in urban and transportation land use rainfall runoff are often adsorbed on or incorporated with entrained particles that are ubiquitous in such runoff. EPP(Expanded Polypropylene) engineered media with a large surface area was developed to treat road runoff. Field application of particle filtration reactor(PFR), which combined the EPP engineered media with filtration called EcoTank system, provided control of water quality. Under the operating conditions with 0.55 hours hydraulic retention time(HRT) and a capable of treating a maximum road runoff 9.5 m³/h, the mean residual Cd, Cr, Cu, Pb and Zn were 0.24, 2.8, 13.4, 11 and 112.3 ㎍/L and corresponding percentage mean removal values were 91, 93, 85, 91 and 80%, respectively. Results suggest that a properly designed PFR can provide effective in situ control for particles and could be combined with or function separately from source control.

Abstract: Due to its irregular structure, the efficiency of the pelletized fibrous filter can be improved if the target substance is line-shaped. Thus, this study was conducted to examine the applications of the pelletized fibrous filter for biological sewage water with line-shaped particles. Towards this end, the pelletized fibrous filter was applied to advanced treatments in which the particles in the sewage water in the supernatant using solid-liquid separation from the final-settling reservoir was filtered with pelletized fibrous filters. To determine the process efficiency of the filter device, a multiparameter water quality analyzer and a data transmission system were established, which showed the efficient process even at a large distance, as well as the good operational status of the filter device. The pilot plant operation results showed that the concentration of TSS in the influent at 20-75 mg/L was reduced to 0.4-10 mg/L in the processed water. The average processing efficiency was 94.9% between 71.4 and 97.9%, and particularly, that of the suspended solids was very high. The results also showed that 27.2% COD_Mn, 22.5% T-N, and 30.0% T-P were removed.

Abstract: Rainwater collection and use is usually considered for runoff from building roofs. Runoff from impervious layers such as roads and pavements, however, has hardly been used as water supply due to its high pollutant concentration. If runoff from roads will be treated and used properly, though, it can be a good water resource and will contribute minimally to a non-point source. In this study, a multistage soil filter system (MSFS) composed of a gravel layer, a functional-media layer with zeolite, a sand layer, and a lawn layer, was developed to treat the runoff from roads and green areas. To evaluate the performance of MSFS, its removal rate of total suspended solids (TSS) was investigated based on the rainfall intensity and the thickness of each layer. The experiment results were compared with the predicted values using the Minitab^TM program. The TSS removal rates ranged from 82 to 96%, with various combinations of experiment conditions. The predicted removal rates well fitted with the removal rates obtained from the experiment. An equation was formulated for predicting the TSS removal rate based on the rainfall intensity and the thickness of each layer. The optimum design factors for MSFS considering its TSS removal rate could be derived based on such equation. Based on the study results, it is expected that MSFS can contribute to securing water resources and to controlling non-point sources.

Abstract: Urban areas consume huge amounts of water and produce much wastewater, which deteriorate the aquatic environment and exhaust the country’s freshwater resources. Water reuse from sewage and wastewater is recognized as a good option for securing water. There are several kinds of processes for improving the water quality. Nutrient removal is very important for water reuse, especially in water supply for outdoor use, to prevent water quality deterioration via eutrophication. Moreover, low cost and easy maintenance should be considered for nutrient removal. In this study, red mud and Bauxsol^TM, a mixed mineral powder made of physicochemically modified red mud residue generated by the Bayer process for alumina refineries, was used for the removal of nitrate and heavy metals in artificial solution, and of phosphate in final effluent, from a sewage treatment plant in Dae-gu, Republic of Korea. Nitrate removal by red mud showed little efficiency while heavy metal removal showed high efficiency. The concentrations of the total phosphate in the effluent and treated water were 1.51 and 0.14 mg/L, respectively, which represent about 90.7% removal. Before and after the treatment, the pH was maintained at a neutral range of 6.5-7.2. Bauxsol^TM also showed a high heavy metal removal capacity. Therefore, Bauxsol^TM in powder and pellet form can be applied individually or mixed with soil to improve water quality for water reuse.