Advanced Materials Research Vol. 663

Abstract: Nitrogen and phosphorus are the nutrients induced eutrophication, therefore the removal of nitrogen and phosphorus is the main target of domestic wastewater treatment. In order to achieve better nutrient removal effect with lower construction and operation cost, a new nitrogen and phosphorus removal process was developed based on simulation. New process named MUST was developed by mixing UCT and step-feed BNR technology together, and possessed the advantages of two processes. The results of simulation show that MUST can achieve similar treating effect with 20% shorter hydraulic retention time (HRT) compared with UCT process. The influent splitting ratio of 4:3:3 was recommended for MUST operation. A pilot experiment of MUST was also carried out according to simulation results, and achieved very good pollutant remove effect, the average COD, NH4+-N, TN, TP removal efficiency were 85.4%, 94.0%, 65.1%, 62.3% respectively under the condition of low influent COD/TN ratio. Considering the excellent pollutant removal capacity of MUST, an upgrade project chose it as wastewater treatment process. This paper just starts the research of MUST, further study is necessary and valuable.

Abstract: Interactive reactor is a powerful and complicated wastewater treatment, it can fulfill various operation modes by changing inlet site, inner recycle site, return sludge site and DO concentration, therefore interactive reactor can adjust to different conditions and achieve steady and efficient wastewater treatment effect. This paper intended to establish integrated optimizing control strategy for better use of interactive reactor. In order to confirm the application boundary of typical operation mode, pilot-scale experiment and simulation were carried out. JHB and ALO modes were experimented for capacity evaluation and simulation calibration. A2/O, inverted A2/O and ALO modes were selected as representatives for the strategy establishment with simulation. According to the study results, inverted A2/O mode was suitable for the influent BCOD/TN value more than 5, A2/O mode was better choice for the influent BCOD/TN value between 4 and 5, and ALO can achieve high nitrogen removal efficiency treating wastewater with influent BCOD/TN between 3 and 4 by short-cut nitrification and denitrification. Contributed to the excellent treating effect of interactive reactor, several projects have been built and run well under the optimizing control strategy.

Abstract: It is important to study theoretical and practical significance on strategic environmental assessment of municipal waste management system. This paper analyzes the research situation of strategic environmental assessment in China and put forward the theoretical basis of strategic environmental assessment on municipal waste management system, including strategic theory, low-carbon theory, cyclic economy theory and sustainable development theory. In the theoretical views, strategic environmental assessment of municipal waste management policies, plans and programs system can be studied for a better and More sustainable management mode of household waste. At the same time, the article gives a research frame of strategic environmental assessment on municipal waste management system in China.

Abstract: Flow outside the water-lifting aerator was simulated with FLUENT software, and the effects of water depth on the in-situ algal growth control using water-lifting aeration technology was numerically analyzed. Under stable state of flow outside the water-lifting aerator, the clockwise flow near the inlet and counter-clockwise flow in other domains coexisted, flow velocity decreased as the distance from the water-lifting aerator increased. When the water depth was increased from 50 m to 110 m, the radius of the core algal growth control zone increased from 60 m to 175 m, and the ratio of the algal growth control zone to the whole flow domain increased from 12.5% to 30.6%. The proper design intervals of water-lifting aerators in reservoirs were proposed as 1.2-1.6 times of water depth.

Abstract: Differential optical absorption spectroscopy (DOAS) is a well-established and widely used technique for monitoring atmospheric pollution. The month performance of a DOAS system was assessed at a certain place in Tianjin University, China, where is farther away from the industrial pollution a source. Three methods were used to inverse the hourly concentrations of nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3). Principal component analysis (PCA) was performed to analyze the retrieving concentrations. Results were obtained for estimated temporal NO, NO2, SO2, O3 distributions over the urban atmosphere; demonstrating the capability of the principal component analysis applied in differential optical absorption spectroscopy (PCA-DOAS) technique.

Abstract: In order to study the thermal stability of PPS (polyphenylene sulfide) filter media, by means of non- isothermal thermogravimetry, thermal degradation kinetics behavior of two kinds of PPS filter media were analyzed. The kinetic parameters of PPS filter media were obtained according to Friedman method. Thermal stability of PPS filter media was discussed. It was found that the initial decomposition temperature and activation energy of N3 sample are all higher than B1 sample, the thermal stability of N3 sample is better than B1 sample, and kinetic analysis can be used as an important method to evaluate the thermal stability of filter media.

Abstract: A complex mass-balanced model of marine ecosystem was developed, including nineteen state variables. In this model, benthos sub-model and improved heavy metal sub-model were coupled with the nutrient cycling.

Abstract: A 2-dimensional hydrodynamic model (RMA2 model) was applied to simulate currents and potential pollutant transport in Jiangyin-Xuliujing reach of Yangtze estuary. The result was compared and validated with a validated 3D model (Delft3D Model). The results indicate that the RMA2 model can achieve the requirements of reproducing and predicting the tidal flow and water levels. Based on RMA2 model simulations, a pollutant transport model (RMA4 model) was established to simulate the transport process of potential pollutant discharge from a sewage treatment plant for risk analysis. This linked hydrodynamic and pollutant transport model can provide the valuable scientific supports for future study of water quality in the Yangtze estuary.

Abstract: Recently, chelating agents have been widely applied to remove heavy metals for their highly effective capacities. In this study, three kinds of adsorption materials, 719 strongly basic anion exchange resin, γ-Al2O3 and activated carbon, were investigated to remove copper(II) under the existence of chelating agent EDDS. Adsorption isotherm and kinetics of copper(II) were assessed in batch experimental systems, pH and initial concentrations were also conducted to evaluate the effects on copper(II) removal. Results indicated the adsorption capacity with three absorbents was enhanced from 0.62, 7.26, 6.73 mg/g to 17.21, 24.68, 24.90 mg/g respectively when the chelating agent EDDS existing in aquatic phase. The experimental isotherms are fitted to Langmuir and Freundlich models, results show that 719 strongly basic anion exchange resin and γ-Al2O3 have good correlation coefficients obtained from Langmuir model, and activated carbon is better to fit the Freundlich model.

Abstract: The effect of reduction characteristics of microbe dissimilating of Fe(III) under different activated sludge, carbon source and anoxic/anaerobic condition was studied by activated sludge as inoculum under laboratory condition. The results showed that the maximum accumulation of Fe(Ⅱ) and the reduction rate of Fe(III) inoculated by biological iron mud were higher than that inoculated by conventional activated sludge. The reduction characteristics of Fe(III) was better in nutrient solution as carbon source than that in sewage as carbon source when inoculated biological iron mud. But the reduction characteristics of Fe(III) was better in sewage as carbon source than that in nutrient solution as carbon source when inoculated conventional activated sludge. From the whole test, the reduction characteristics of dissimilating Fe(III) microbe under anaerobic condition were better than that under anoxic condition.