Applied Mechanics and Materials Vols. 209-211

Abstract: A promising humus activated sludge process with microorganism cultivation reactor filled with humus soil pellets on the basis of traditional activated sludge technology was developed in Japan and used to improve sewage treatment efficiency. Since 1980s, humus activated sludge process was successfully applied in Shimauchi Housing Complex of Matsumoto City, Yamanouchi Sewage Treatment Center and Sewage Treatment Facility at Nagayoshi Agriculture Hamlet and was applied in more than 200 sewage treatment plants in Korea. The operating results showed that the process has the advantage of excellent pollutant removal performance and sludge dewaterability and no odor release.

Abstract: The purpose of this study is to investigate the efficiency and characteristics for treatment of polluted landscape water using filamentous bamboo as bio-carrier. Results demonstrated that the COD removal rate could be increased more 13% because glucose was added into the raw. And the COD removal was mainly decided for the biofilm on the filamentous bamboo, which is 2.53 times higher than activitcd sludge in a batch hybrid unit. Additionally, Rich biological phases was obversed during the test.

Abstract: During drinking water treatment, the chemical dosing processes, such as coagulant dosing process, ozone dosing process and chlorine dosing process are usually manually operated based on the operator knowledge and experience. However, due to the variations of water quality, water flow and process operational conditions and characteristics of large time-delay and nonlinear for the chemical dosing processes, it is difficult to adjust the chemical dosages in time by operators to keep the treated water quality stable, especially during the periods of rapid and frequent variations of water quality, water flow and process operational conditions. Thus, the improvements of control methods for the chemical dosing processes are essential to the operation of drinking water treatment plants. The Xiangcheng Water Treatment Plant in Suzhou, China has been utilizing the automatic control for chemical dosing processes since February 2012. Automatic controllers are designed respectively for the coagulant dosing process, ozone dosing process and chlorine dosing process. After the implementation of automatic control, operators are not necessary to keep constant attention. In addition, due to the improvements of control accuracies for the chemical dosing processes, the chemical dosages are reduced on the premise of ensuring safe water. Thus, both of the human resource costs and material costs can be saved. The practical control results demonstrate the efficiencies of proposed methods.

Abstract: In this experiment, the combination of physic-chemical and biological methods was applied. Firstly, degreasing wastewater and painting wastewater were pretreated by chemicals respectively. And the removal rate of COD_Cr is more than 50% and about 65% respectively. After pretreatment，the effluents together with electrophoresis wastewater were treated by the coagulation-flotation and SBR process. And the removal rate of COD_Cr reached more than 80%, which achieved primary standards of "Integrated Wastewater Discharge Standard"(GB8978-1996). After the separated pre-treatment, the consuming amount of the chemicals had obviously lowered than the conventional mixing treatment, as well as the sludge. Most importantly, this process ensures good quality of water. So it is feasible economically and technically to use separated pretreatment, air flotation and SBR to treat automotive painting wastewater.

Abstract: The properties of four different activated carbon fiber cloth (ACF), such as specific surface area, pore volumes and pore size distribution, were evaluated. The relationship between ACF properties and its electrosorption performance was analyzed. The experimental results show that pore structure has more influence on the performance of ACF electrode than that of specific surface area for ACF material. More abundant mesopores and shallower pore channels for ACF is favorable to improve the specific capacitance and electrosorption capacity of ions.

Abstract: Other than silt density index (SDI), modified fouling index (MFI) is claimed as one of most useful fouling predictive tools in the practice of reverse osmosis. In this study, the effect of colloidal silica particles on the MFI value with the presence of crossflow sampler (CFS) cell at the upstream of MFI setup was systematically investigated. Colloidal silica with the particle size ranging from 70-100 nm was used as the model foulant in this experiment. The feed silica suspension was 0, 50, and 200 mg/L. The effect of membrane pore size as the test membrane in the dead-end cell on the fouling indices was also studied. Polyvinylidene fluoride (PVDF) membranes with molecular weight cut-offs of 150 and 100 kDa were employed. As predicted, the experiment results demonstrated that the fouling indices increased significantly as the feed silica concentration increased. The CFS-MFI values were always lower than the MFI in all the fouling index tests due to the shear force effect generated under the crossflow filtration mode. The fouling index generated from PVDF100 was higher than that of PVDF150 due to the retention of smaller particles. For this reason, PVDF100 membrane was preferred to be used as the test membrane for fouling index tests using colloidal silica over the PVDF150.

Abstract: Adsorption and desorption kinetics is critical in the efficiency and performance evaluation of the adsorbents. In this study, the adsorption and desorption kinetics of copper and/or zinc ions was investigated with the polyamine-functionalized adsorbents (P-TETA). The adsorption kinetics was studied in both single species system (when only one metal ion was present) and binary species system (when both metal ions were present). The adsorption kinetics in single species system was well fitted with two models at two stages for both Cu and Zn ions, indicating that the adsorption was diffusion-controlled at the initial stage and attachment-controlled at later stage. The adsorption kinetics in binary species system revealed the stronger coordination affinity of Cu ion with P-TETA than Zn ion. The desorption kinetics was well fitted with Elovich model for Cu ion desorption only, in both single and binary species system, with a higher desorption rate in single species system.

Abstract: The feasibility of coal gangue as an adsorbent for phosphate removal from wastewater was investigated. The results showed that the equilibrium data were well fit to Langmuir isotherm model and the maximum adsorption capacity calculated was 2.49 mg/g at 25°C. The adsorption process followed pseudo-second order model. And the practical waste water experiment indecated that the phosphate concentration of real sewage decreased from 0.625mg/L to 0.121mg/L. These results suggested that coal gangue can be used as an adsorbent to removal phosphate from wastewater.

Abstract: High temperature peanut meal was fermented by double strains with solid-stated fermentation, using fermented product dissolved in water and via membrane separate, then obtained four molecular weight distribution(MWD), which were 10kDa. Using four MWD fermentation peptides do experimenting, separated, that is hydroxyl radical-scavenging, DPPH radical-scavenging, reducing power and ferrous ion-chelating, and compared with GSH, it shown that the peptides of 3kDa~10kDa MWD fermentation peptides have the max antioxidant activity, the second was the percolator of >10kDa MWD fermentation peptides, then was the peptides of 1kDa~3kDa MWD fermentation peptides and <1kDa MWD fermentation peptides had the least activity.

Abstract: PAN-based carbon fiber (CF) was modified by electrochemistry using H2SO4 and maleic anhydride (MA) in current rearch. The CF surface morphology and natures were characterized by specific facilities, such as laser confocal microsopy (LCM), Fourier transform infrared spectroscopy (FTIR) and the degree of moisture. On the other hand, the biocompatibility nature was indicated by immobilization results of microorganisms on CF. The outcomes show that the surface hydrophilicity, oxygen-based function-groups and surface roughness of CF would contribute greatly to improve the immobilization ability of microorganisms on CF surface. And H2SO4 anodic oxidation on CF has more effect on microorganism immobilization than MA electropolymerization.