Applied Mechanics and Materials Vols. 295-298

Abstract: To improve the ecological footprint model in aspect of reflecting sustainability of the economic, social and technological, the emergy analysis and socio-economic system development index were introduced into the model. The modified ecological footprint model was applied in the calculation of ecological carrying capacity and ecological footprint in Tibet, China. The ecological carrying capacity/cap is 19.13hm2, and the ecological footprint/cap is 8.96hm2. The result shows that the Tibet region is under the condition of ecological surplus and it is suitable for further programs development to some extent. But the high proportion of energy resources, cement and fertilizer utility should draw attention during the exploitation or construction progress.

Abstract: After 20 years of innovation, the economy of Vietnam has achieved high growths with lots of advantages for the country’s industrialization and modernization process. The country has gradually reduced poverty, created more jobs, improved people's life standards and narrowed down the economic gap between its own and that of other countries in the world. However, economy growths have at the same time caused big pressure on the quality of the environment, especially in big cities like Hanoi and Ho Chi Minh city. The environmental problems such as water pollution, air and solid waste are becoming more and more serious. This paper presents discussions on the following issues in the case of Hanoi: (1) an analysis of the economy development from 2008 up to present; (2) the influences of industrialization- modernization-urbanization process on environmental quality; (3) an analysis of the environmental pollution; and (4) a proposal of the possible measures to protect living environment towards a sustainable development.

Abstract: This paper puts forward environmental bearing capacity relative surplus rate and calculation model based on the theory of environmental bearing capacity, Through collecting and estimating the predictive value and ideal value of each index in different development stages and schemes, using analytic hierarchy process to established the target weight, environmental bearing capacity relative surplus rate of the rule layer and index level in Qian’an Mining area are calculated through the gradual convergence principle, accordingly the optimal solution to improve the environmental bearing capacity of Qian’an mining area is determined ,which provides scientific basis for promoting to realize the sustainable development of Qian’an Mining area.

Abstract: The Material Flow Analysis (MFA) method is often discussed in terms of water resources management. This paper attempts to measure and analyze the flow of nitrogen and phosphorus from wastewater sources to assess the trends and patterns of strain in environmental metabolism.Comparison between nitrogen and phosphorus accumulates in wastewater shows that, P discharged values to sewer system are lower as compared to N. Kemaman dan Kuala Terengganu are the dominant region that generating high volume of P and N-wastewater discharge.The study also delved mostly into recycling level of effluent and sludge, with only 3 to 5% of both products were reuse for agriculture and economic purpose. In conclusion, MFA techniques have been proposed to help the decision-makers in waste and nutrient management planning especially on implementing policies related to water and wastewater sectors.

Abstract: This article evaluated the plantation potential of Pistacia chinensis in Sichuan Province of China based on the spatial analyst technology of Geographic Information System and Analytic Hierarchy Process. The evaluation results show that the high suitable, suitable, moderate suitable and no suitable areas for the plantation of P. chinensis are 28×104hm2, 160×104hm2, 177×104hm2 and 690×104hm2 respectively. The high suitable areas of shrub land, open forest land and unutilized land for its plantation are 9×104hm2, 16×104hm2 and 3×104hm2 respectively. The high suitable regions distribute in fifteen prefecture-level cities. Yibin City has the biggest high suitable area with 4.92×104hm2. Dazhou City has the biggest suitable area of 23.47×104hm2. Ganzi Tibetan Autonomous Prefecture and Aba Tibetan and Qiang Autonomous Prefecture aren’t suitable for its plantation basically. The evaluation results can provide scientific basis for the planting plan of P. chinensis to a certain extent.

Abstract: Taking No.11 flue gas desulfurization (FGD) site in Taiyuan Second Thermal Power Plant (TSTPP) as an example, the authors respectively deduced the models of technical performance indexes including SO₂ removal efficiency and outlet SO₂ concentration and the models of economical performance indexes including limestone consumption, power consumption and process water consumption. Then, by using the least square linear and nonlinear regression method, the authors obtained the practical mathematic models in the period of 21:00, Mar. 28th and 3:00, Mar. 29th, 2007. Finally, the authors calculated the optimal solutions of slurry pH value, calcium-sulfur (Ca/S) mole ratio and liquid-gas (L/G) ratio by utilizing the multiobjective programming method. Using this method, the desulfurization system works safely and economically.

Abstract: To study the special hydrodynamic characteristic in the estuary of Xiangxi River, this project monitored water temperature and flow velocity both of Yangtze River and Xiangxi River in 2010. In addition to monitoring the water environment of two rivers, a three-dimensional (3-D) hydrodynamic model was also applied. By utilizing both field data and a numerical model, a more holistic view of the 3-D thermal density currents was discovered than by using either method alone. The results of the study showed that the invasion form of water from Yangtze River changed along with the variation of differences in water temperature between two rivers. The invasion water influenced the flow field and thermal field distributions in the estuary of XXR: The farther away from the river mouth, the thermal stratification was stronger and the water temperature horizontal distribution was more uniform. Flow velocity decreased as the distance from the river mouth increased

Abstract: The pilot-scale Anoxic-Anaerobic-Microaerobic-Aerobic (A2O2) biological nitrogen removal process was used to treat the wastewater from nitrogenous fertilizer production with C/N ratio of 1~2. Batch tests were conducted to investigate the patial nitrification using the activated sludge from the microaerobic tank rich in nitrite bacteria as the experimental object. Results showed that 95% removal efficiency of NH3-N could be obtained with the HRT of 30 h. The SVI affected the NH3-N removal rate and the optimal SVI was 106 mL/g. The ORP was well correlated with the logarithm of NH3-N concentration with the linear regression equation of y=-57.233x+3.308. Moreover, the kinetic model for partial nitrification was determined as v=4.762s/(9.86+s).

Abstract: The membrane-bioreactor (MBR) is a combination technology that includes biological treatment and membrane filtration separation. According to the test, it studied the use of membrane bioreactor reuse in municipal wastewater treatment and reuse. The test measured every target about treated water quality,NH₃-N,TN,COD_cr,Sludge concentration and Turbidity. The results of the test show that the MBR can get efficient solid liquid separation to obtain the recycled water directly, and can maintain high concentration of microbial biomass in bioreactor. In addition, it can increase the volume of load handing equipment, and reduce floor space.

Abstract: Multiphase flow mixed microbubble generator (MFMMG) is an effective generator and has many advantages, such as simple structure, easy maintain, small, high efficiency, and so on. The paper found out the important influences for performance of MFMMG and analyzed them. The experiment showed that the analysis is correct and efficient. The paper will be useful for analyzing and designing microbubble generators.