Applied Mechanics and Materials Vol. 700

Abstract: This paper predicts and analyzes the output, energy consumption and CO₂ emission in Chongqing’s cement industry in 16 years to come using a dynamics simulation system of carbon emission. A comparison with historical data indicates a desirable goodness of fit of the simulation results, which show that the cement output in Chongqing will reach the peak of about 95 million tons in 2020, followed by a slow decrease to 90 million tons towards 2030; the energy consumption will reach a maximum of some 7.8 million tons of standard coal in 2020; the CO₂ emission will reach about 76 million tons in 2020, followed by a drop to 60 million tons towards 2030, equivalent to the 2015 figures. Based on the data, this paper analyzes the influence of different technical paths and policy options on emission in various developmental scenarios, and proposes specific paths for emission reduction.

Abstract: The degradation behavior and mechanism of biologically pretreated coking wastewater (BPCW) were investigated by means of a lab-scale electro-coagulation (EC) in static methods. The results showed that the percent COD and color removal can reach 80.5 % and 95.4 % respectively under the optimal conditions (initial pH of 8.0; reaction time of 30 min; current density of 14.0 mA/cm² and NaCl dosage 1.6 g/L).

Abstract: This paper predicts and analyzes the output, energy consumption and CO₂ emission in Chongqing’s electric power industry in 16 years to come using a dynamics simulation system of carbon emission. A comparison with historical data indicates a desirable goodness of fit of the simulated results, which show that the power generation in Chongqing will reach the peak of about 180 billion KWH in 2020 and 378 billion KWH in 2030, followed by a steady rise in the following 15 years; the per capita power consumption will reach 5350 KWH in 2020 and 12,000 KWH in 2030; the CO₂ emission will reach about 102,200,000 tons in 2020 and about 232,600,000 tons in 2030; the CO₂ emission per unit electricity generation will reach 570gco2/kwh in 2020 and about 620gco2/kwh in 2030. Based on the data, this paper analyzes the influence of different technical paths and policy options on emission in various developmental scenarios, and proposes specific paths for emission reduction.

Abstract: Impact of air pollution on health has become an important social issue. Air pollution is closely related to the morbidity and death rate of cardiopulmonary disease, produces short-term acute and chronic hazards on health, and especially has long-term and profound impact on primary and secondary school students’ constitution. Long-term effects of air pollution on cardiopulmonary function of primary and secondary school students are represented as incidence increase of asthma, decrease of FEV1, MMEF, VO_2max, MVV and other indicators and relation to NO, PM2.5 and CO. Students taking exercise in air pollution environment can cause acute cardiopulmonary reactions, such as abnormal changes of MVV, VC, FEV1, FVC and other indicators after exercise, which may relate to O₃, PM₁₀, PM_2.5, SO₂ and NO₂. Therefore, schools should strengthen the awareness of air pollution in implementing sports, and conduct development of control measures, to ensure the effect of physical exercise.

Abstract: Two samplings of municipal solid waste (MSW) were conducted at four MSW incineration plants at Kaohsiung City. Samplings were conducted in April and July of 2013 at different seasons. Physical composition was analyzed to find out the content of heavy metals in combustible and incombustible MSW. In 2013, the weight percentage for combustible MSW in Kaohsiung area was at 95.59%. It means that combustible MSW in Kaohsiung area is above 90%. Incombustible metals and non-metals have less content in terms of percentage. The possible reason might be valuable metals have been recycled. In 2013, the average content of heavy metals in Kaohsiung area from high to low came in this order: Pb>Zn>Cu>Cr>Cd. The average content of Pb was 155.10 mg/kg. Cd was at minimal level with average content lower than 1.00 mg/kg. The average content of Pb was 147.84 mg/kg. Cd was at minimal level in Kaohsiung area with average content lower than 1.00 mg/kg. MSW amount in Kaohsiung area for the first sampling in April 2013 and the second sampling in July 2013 were respectively at 35491 and 36062 tons. According to this research, the content of heavy metals in MSW was respectively 146.88 and 411.56 mg/kg. The content of heavy metals were calculated at 5.21 and 15.92 tons, which equal to 0.01% and 0.04% of the total amounts of MSW. After incinerating, they contain byproducts of heavy metals such as ashes, smoke emission, and dust.

Abstract: pH parameter is one of the main factors influencing organic degradation in the sewage treatment, and the degradation of organic matter in biochemical treatment unit is the largest, the hydrolysis acidification processing unit is the second largest. When the water pH range of biochemical treatment unit is [6.8 7.2], organic degradation is in the largest degree. The pH range of neutralization unit must be based on a subsequent hydrolysis acidification treatment unit, in order to adjust the pH range dynamically. Finally we make wastewater treated by biochemical unit meet the pH standard, and make the organic matter degrade in the largest degree. We designed chemical wastewater pH intelligent control device based on MSP430F149 MCU. The application of this device shows that the method has high control accuracy, less drug consumption and has large organic matter degradation in the sewage treatment plant, etc.

Abstract: Based on the working process of the traditional sewage treatment process, this paper aims at reform the defects of intelligent energy-saving. This system uses various sensors for on-line monitoring of wastewater parameters and uses the PLC to control the air blowers. Under the premise of guarantee the quality of water, this reform system can achieve the effect of energy conservation and emissions reduction.

Abstract: Treatment of actual coking wastewater considered to be difficult by traditional systems. The present study is related to treatment of actual coking wastewater through microaerobic EGSB reactor. The study showed the EGSB reactor could attain about 75% high COD removal. Increasing V_up could strength COD removal. Moreover, high sludge concentration and profound communal synergism existing within the dense granules were very important. As a result of the kinetic analysis of the EGSB reactor treating actual coking wastewater for COD removal using a modified Stover–Kincannon model, the maximum substrate utilization rate, v_max, half saturation constant, K_S, inhibitor constant, K_I, actual pollutant removal rate, , and the actual inhibition degree, K_S /K_I were determined as 2.65×10^-3h^-1, 39.57mg.L^-1, 415.82mg.L^-1, 6.7×10^-5h^-1.mg^-1.L and 0.1(before increasing V_up), 7.34×10^-3h^-1, 19.53mg.L^-1, 197.76mg.L^-1, 3.7×10^-4 h^-1.mg^-1.L and 0.1(after increasing V_up), and 9.35×10^-3h^-1, 6.38mg.L^-1, 162.81mg.L^-1, 1.47×10^-3 h^-1.mg^-1.L and 0.04 (after increasing V_up and X), respectively. The inhibition of toxic contaminants in the actual coking wastewater would cause the decreasing of pollutant removal rate, however, enhancing and X (simultaneously optimizing sludge aggregate structure) could strengthen the performance effect.

Abstract: The titanium-based nanocatalysts were prepared and used to photocatalytically oxidize Hg⁰ to remove it in the simulated flue gas in this paper .The modified commercial degussa P25 and Fe³⁺ doped TiO₂ photocatalyst prepared with sol-gel method were applied to conduct the experimenent on self-built experimental platform to test their photocatalytically oxidation performance on mercury in the simulated flue gas.By designing different ratios of Fe₂O₃/TiO₂, comparison experiments under UV(ultra violet) irradiation, it was compared with the result of the experiment and reference documents to verify the rationality of the experimental results and the accuracy. The best catalyst modification conditions were determined and analyzed the Fe-doped TiO₂ photocatalytic mechanism to guarantee high or higher mercury removal from flue gas.

Abstract: The pervaporation membranes were prepared by using poly dimethyl siloxane (PDMS) as precursor, toluene as solvent, triethoxy methylsilane as cross linker, dibutyltin dilaurate as catalyst. The PDMS membranes were evaluated with permeation flux and separation factor. The effects of cross linker dosage and the operation parameters during the process of pervaporation were investigated. It was shown from the results that: The selectivity of the membranes increased while the permeation flux first increased and then decreased as the linker dosage increased; the selectivity of the membranes decreased while the permeation flux increased as the feed temperature increased; the selectivity and the permeation flux of the membranes both increased as the feed concentration increased; the selectivity and the flux also both increased as the feed flow rate increased; the selectivity increased while the permeation flux decreased as the separation press increased. When the proportion of the PDMS, solvent, cross linker and catalyst were immobile, The permeation flux and separation factor could be 98mg/(m²·h) and 5.12 when the feed temperature was 60°C, feed concentration was 0.5g/L, feed flow rate was 0.6L/min and separation press was 6KPa.