Applied Mechanics and Materials Vols. 675-677

Abstract: Test by establishing different embankment flowing systems studied the combination of different substrates and different plants purification efficiency and the effect on the stability of the efficiency of the flowing system. Results show that, the mixed matrix(loess, sand and brown loam) is more efficiency than the single matrix, especially for suspended solid (SS), ammonia (NH₃-N), total phosphorus (TP) removal, the removal rate is over 60%. Tall fescue (Festuca elata Keng ex E. Alexeev) is more suitable for the flowing system than perennial ryegrass (Lolium perenne L.). And, long running of the system is possible.

Abstract: Wastewater containing oil and polyacylamide is a kind of organic wastewater, which is hard to treat. The combined process of moving-bed biofilm reactor and sulphate-reducing bacteria was used to treat the wastewater. Operating conditions of moving-bed biofilm reactor and sulphate-reducing bacteria were studied. Results indicate that the oil removal efficiency by moving-bed biofilm reactor can reach above 90% with 9 hours hydraulic retention time at 25°C, but it has no effect on polyacylamide. Sulphate-reducing bacteria can degrade polyacylamide, and polyacylamide conversion is about 50% at 37°C with 4 days culture time and 9ml inoculation size. The effluent quality of wastewater containing oil and polyacylamide can meet requirements of the first level in integrated wastewater discharge standard.

Abstract: Cu-OMS catalyst reveals well catalytic performance on the oxidation-reduction reactions of gasoline engine exhaust. The catalysts were characterized by means of XRD, nitrogen physisorption and oxidation-reduction reactions. The results of the catalytic tests revealed that CO conversion can get 95% at as low as 150°C and achieve 100% at 200°C through 2CO+O₂→2CO reaction, while CH₄ and NO conversion can achieve 87% and 90% at 300°C respectively. The Cu-ML corresponds to a type IVisothermal, and Cu-OMS corresponds to a type II isothermal. High Cu dispersion in manganese oxide crystals and low agglomeration are the main reason for high activity.

Abstract: In situ chemical oxidation with persulfate (PS) anion (S₂O₈^2-) is a viable technique for remediation of groundwater contaminants such as trichloroethylene (TCE). This laboratory study investigated the use of the oxidant sodium PS for the chemical oxidation of TCE at different conditions to determine the influence of temperature, pH, and the PS/TCE molar ratio. Experiments revealed that higher temperatures, lower pH, and higher PS/TCE molar ratios were to the benefit of TCE oxidation by PS. By investigating the reaction kinetics, the degradations of contaminant can be described by use of pseudo-first-order reaction. At the temperatures ranging from 25°C to 40°C, the activation energy for the degradation of TCE was determined to be 85.04 KJ/mol.

Abstract: The sewage diffusion is an environmental material for protecting marine environment. It plays an important role in port engineering. Its effect under deep water was carried out between different diffuser design parameters based on the hydraulic model test, and YangKou port sewage marine disposal project phase II was taken as an example. For this project, jet angle was controlled to be 0 degree, and horizontal angle was controlled to be 0 degree. It not only can ensure that sewage fully diluted mixed, also can avoid the premature convergence and sewage lifting. It is feasible for selecting large angle nozzle under deep water and there are some technical bases have been provided for other sewage marine disposal project.

Abstract: The results are shown that: When the overlying water pH is 7.0, the least impact of nitrogen, phosphorus and organic matter release in sediment. Under the neutral condition, after sediment release in deionized water NH₃-N concentration was 1.86 mg.L^-1, TP was 0.09 mg.L^-1, COD was 22.2 mg.L^-1 . In the nature water sediment release experiment, compared with no adjustment of pH the NH₃-N emissions reduce by 9.4%, the sediment adsorbs TP from water increases 2.3 times. Through a period of a month typical lake quality monitoring found that there is presence of sediment NH₃-N release into the overlying water and sediment adsorb TP from the overlying water.

Abstract: Using process software Aspen Plus of coal-fired power plant carbon dioxide capture flue gas pretreatment system simulation, studied the flue gas quantity、packing layer height、absorbent in quantity and absorbent in temperature, influence on the content of SO₂ and cooling in the flue gas outlet. The results showed that the content of SO₂ and temperature in the flue gas outlet, increase with increasing the flue gas quantity, decrease with increasing the packing layer height and absorbent quantity, increase with the rising of absorbent temperature.

Abstract: The study explores pretreatment of textile Wastewater by using CaO2/H+/Fe2+ advanced Fenton-like oxidation technology. The result show that when the initial COD is 2200mg/L, the pH=3, the reaction time is 40min, the speed is 150r/min, the dosage of calcium peroxide is 24g/L and the dosage of FeSO4 is 2g/L at 25°C, the removal rate of COD reach 81.82% and the decolorization rate is 99.93%. Compared to the pure CaO2 oxidation, COD removal rate increased significantly and its processing effect is greatly increased; whereas Compared to the advanced Fenton oxidation technology, this kind of Fenton-like system greatly reduces the cost, improve the effect of effluent, provide new way for calcium peroxide used in wastewater treatment.

Abstract: The change rule of characteristics of activated sludge in urban sewage treatment by activated sludge process were investigated at low temperature of 15°C~3°C.The results showed that with the temperature decreased, average particle size and dehydrogenase activity showed a trend of decrease; sludge settlement ratio and sludge volume index and sludge extracellular polymeric substance showed a trend of increase.

Abstract: In the combustion process of pulverized coal injection into blast furnace, the chlorine goes into the unburned pulverized coal is about 17%, the chlorine in the unburned coal keeps original state; The chlorine goes into the blast furnace gas is about 83%, and these chlorine stay as Hcl gas. Changes in air temperature and oxygen rate had no significant effect on the decomposition of chlorine in coal, resulting the rate of Cl into the blast furnace gas is difficult to increase significantly.