Advanced Materials Research Vols. 955-959

Abstract: In the context of global sustainable development, traditional wastewater treatment models reveal its shortcomings due to lack of recovering resource and energy in wastewater. Sustainable wastewater treatment technologies, taken wastewater as carriers of resource and energy, have been paid close attention. Starting from the existing problems of present wastewater treatment technology and focusing on the concept of resource recovery and energy utilization, this paper discussed the production technologies for hydrogen, electricity, diesel and methane from wastewater based on carbon resource recovery, and nitrogen resource treatment technologies with low energy consumption (such as shortcut nitrification-denitrification, ANAMMOX and SND). The latest research processes were also summarized. The research and development orientation of sustainable treatment technology for urban wastewater was put forward.

Abstract: Toxic effects of phenol on the activated sludge process were evaluated by determining the changes in DO in a laboratory-scale unit. A series of phenol concentration significantly affected the activated sludge. The effect of phenol was variable depending on its concentration. With the increase of phenol concentration, oxygen uptake rate (OUR) decreased. The inhibitory concentration that reduced the sludges specific oxygen uptake 50% from its maximum rate was determined (IC₅₀).

Abstract: Using the automatic driving process of urban sewage treatment project risk model, combining with the characteristics of sewage disposal engineering project financing, putting forward the model of urban sewage treatment project financing risk. Cognizing and distinguishing on urban sewage treatment project financing risk. Delphi analytic hierarchy process is used to quantitative analysis for getting urban sewage treatment project financing risk hierarchy, using fuzzy comprehensive evaluation model for its optimization research.

Abstract: Sludge with large production is difficult to be dewatered without any pretreatment. Pretreatment with ultrasound and microwave can adjust the structure of sludge and change the water form, therefore increase the water content which could be dispelled easily. Dewaterability and morphological of sludge from sewage treatment plant including microwave and ultrasound were studied. Capillary Suction Time (CST), viscosity, Settle Volume (SV), water content, Chemical Oxygen Demand (COD), Zeta potential and morphological characteristics were tested. After microwave modification, the particle size of sludge ranged from 33.55μm to 28.98μm, and fractal dimension was about 2.8. Microscopic image analysis showed that the particle of sludge became coarse. After ultrasound modification, the particle size of sludge ranged from 33.55μm to 9.44μm, fractal dimension was about 2.9. Thus, the smaller particles were observed after ultrasound. The gray associate degree coefficient of viscosity and moisture content is the bigest. Through the analysis of dewatering characteristics of sludge and water content, a model which contributes to predict moisture content of sludge online was established.

Abstract: The inertial effect applied to activated sludge process, the practice shows that in energy efficiency and reduce the hydraulic retention time it is obvious than not using the inertial effect. In cold winter areas to ensure water quality can meet the first grade A standard of "Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant" (GB18918-2002)

Abstract: Constructed wetlands (CWs) are shown to be suitable for the treatment of water contaminated with benzene. However, due to the high sulfate concentration (around 850 mg/L) in influent, sulfate reduction will be stimulated in CWs. Subsequently, the toxicity of sulfide will be a catastrophe to the plants, and the treatment performance of CWs will be impaired. In this study, nitrite and nitrate were used as competitor with sulfate for electron acceptor to prevent the sulfate reduction. With the inflow benzene concentration ranged from 21.6-103 μg, and the accumulation of sulfide reached up to 39%, the removal efficiency of benzene decreased from 86% to 27%. However, with the addition of nitrite and nitrate, the sulfide accumulation was inhibited successfully, and the benzene removal efficiency recovered to 85%. In conclusion, both nitrite and nitrate can be an option for preventing sulfate reduction and sulfide toxicity in CWs treating sulfate-rich wastewater.

Abstract: In conjunction with theoretical heat exchange model, experimental investigations have been conducted for a coupled system of Selective Catalytic Reduction (SCR) and Regenerative Heat Exchange (RHE), to reduce nitrogen oxides (NO_x) from coal-fired boilers and High Temperature Air Combustion (HiTAC) furnaces. Results indicate there is no effect of catalysis reactions on heat transfer; catalysts serve the function of heating elements. The outlet NO concentration periodically decreased in an almost linear fashion. NO conversion: i) rose slowly with a longer switching time; and ii) reached the peak value of temperature with a delay compared with the steady state. The coupled system requires less space and hence is a suitable option for SCR renovations in coal-fired power plants.

Abstract: The palm industry in Malaysia is a growing industry as from a mere 400 hectares planted in 1920, the hectarage increased to 5 million hectares in 2011 [1]. A by-product known as palm oil fuel ash (POFA) was a waste from the palm industry. Uncontrolled dumping of POFA give a serious impacts to environmental which creates pollution and health hazard. In this paper, the material characterization of POFA as an additive material to granite residual soil in terms of physical, mineralogical, chemical and mechanical properties has been investigated for the potential usage of the material. Results showed a general improvement of soil sample when mixed with POFA in all physical properties. The domain mineral present in natural soil is kaolinite. The mechanical behaviour also showed an improvement especially when compared to the landfill hydraulic barrier requirements.

Abstract: The flow field in anaerobic reactor is very complex, but it has been given wide attention because of its important impact to wastewater treatment effect. It is often studied by numerical simulation. The paper explored the research progress of simulation on the flow field in anaerobic reactor by the summary of development of anaerobic reactor and principle and characteristics of computational fluid dynamics simulation and introduction of study and application status on numerical simulation. And then it gave its opinion on the development of simulation on the flow field in anaerobic reactor in future.

Abstract: This article uses the field investigation and data collection methods, study of the status of the handan iron mining area ecological restoration. Through field survey, Studies the mine soil physical and chemical properties, biological diversity and the dominant species of space and time change. Using the method of data collection and analysis, by collecting data, studies the relationship between the ecological restoration of each factor, we may discover the laws of ecological restoration, to determine the steps and methods of ecological restoration of handan iron mining area.