Papers by Keyword: Ozone

Abstract: This experiment used SODO^TM ozone catalytic oxidation technology treated MBR effluent of a advanced treatment project of water treatment company in pilot scale test, which studied the effect of SODO^TM oxidation and resolved the problem of MBR effluent drainage system can not meet the standards of "Discharge standard of pollutants for municipal wastewater treatment plant " (GB18918-2002). Operating parameters of the test device: Ozone dosage was 200mg/L•h, system contact oxidation time was 4h, the average of effluent COD_Cr was about 100mg/L by controlled the dosage and other parameters at the economical operating conditions.

Abstract: With the living standards improvement of rural residents, people pay more attention to the safety of drinking water in China. As the final step in drinking water treatment, disinfection technology has received much attention. At present, drinking water disinfection process is mainly involved in chlorine disinfection, chlorine dioxide disinfection, chloramine disinfection, disinfection of potassium permanganate, ozone disinfection and ultraviolet disinfection. However, due to limitations in rural economic conditions and management level, only ozone disinfection and ultraviolet disinfection are suitable for rural areas in China. This paper described some of the application problems and limitations in drinking water disinfection process, as well as the select principle in rural areas. The principle, research status, trends and issues in application of ozone and ultraviolet disinfection technology were emphatically introduced. Finally, the development of drinking water disinfection technologies was discussed.

Abstract: The removal of Bisphenol A in river water can be accomplished with the application of ozone. Ozone is widely used to disinfect drinking water due to its strong oxidizing properties. This study was conducted to investigate the removal of Bisphenol A in different areas of Skudai River. Batch experiments were conducted at initial Bisphenol A concentration of 0.5 mg L^-1. The concentrations of Bisphenol A and dissolved ozone were measured using Ultra High Performance Liquid Chromatography (UHPLC) and UV-Visible spectrophotometer respectively. Based on the results obtained the stability of ozone in the water were very fast. Ozone was quickly decomposed in water samples. The results indicated that the depletion of ozone varied from different dissolved organic carbon (DOC) value of water samples. Concentration of dissolved ozone was reducing rapidly after spiked into high DOC value (9.17 mg L^-1) of river water. The results of the study have shown that ozonation could be used to effectively remove the Bisphenol A from water. The ozone depletions in river water at 120 seconds were about 87%-99%.

Abstract: Accurate value of absorption cross section is required for correct measurement of ozone concentration. Measurement of ozone has been done at different altitude and pressure. However, previous work has failed to establish significant relation between pressure and ozone absorption cross section. Therefore, this work aims to establish relation between pressure and maximum ozone absorption cross section via spectralcalc.com gas cell simulator. Simulation results show maximum absorption cross section 1.148×10^-21 m² molecule^-1 and maximum absorption wavelength 255.442 nm are independent of pressure changes from 0.1 atm to 3.0 atm. Thus, measurement of ozone concentration at maximum absorption wavelength is strongly recommended due to negligible pressure dependence.

Abstract: To clarify the influence of air pollutants emitted from East Asia on the ozone air quality in Taiwan, this study performs a long-term simulation result for 4 months using Taiwan Air Quality Model. Influence from the current (2007) and future (2020) East Asian emissions on the ozone concentration in Taiwan were simulated. The date ranges simulated were February, May, August, and October of 2007, representing the seasons of winter, spring, summer, and autumn. Influence from transboundary transport on Taiwan was assessed based on simulations of these 4 months. The influence of transboundary transport on the monthly average of daily peak ozone concentrations in Taiwan is 15.5 ppb. Worst case scenarios in 2020 will contribute an additional 3.7 ppb. If the size of ozone pollution area (≧120 ppb) is considered, transboundary transport contributed to 72 % of the polluted area in 2007; the ozone pollution area in the worst case scenario in 2020 will further increase by 47 % from 2007 levels.

Abstract: Airliner cabins present more complicated scenario due to different design and operation challenges owing to the extreme environmental conditions, complexity of the operational systems, and the authorities that govern such environments. The scientific evaluation is rendered difficult due to lack of empirical evidence determining the airliner cabin air quality as well as consequent health effects occurring due to short or long flight exposure. Crew members and passengers report dizziness, fatigue, headaches, sinus and ear problems, dry eyes and sore throats during and after travel. There are persistent concerns about the transmission of infectious agents such as influenza, tuberculosis and measles viruses during flights. Moreover, a systematic collection of data related to airplane environmental exposures is not yet available and the effects of environmental conditions on wellbeing of travelers and their comfort level are yet to be fully ascertained. In this work, a systematic review of the air quality inside the airliner cabin are discussed. The potential pollutants and their established causes are discussed. In addition to this, major health discomforts faced by the occupants are presented.

Abstract: In order to reduce environmental pollution and recycle the intercalating solution, a new way to prepare expandable graphite (graphite intercalation compound, GIC) by ozone oxidation was proposed. The influences of the intercalating solution, reaction time, ozone flow and concentration of sulfuric acid on exfoliated volume (EV) were discussed in detail. The EV of H₂SO₄-GIC is much bigger than that of HClO₄-GIC or fuming HNO₃-GIC. The optimum condition with the maximum EV of 285 ml/g at 950°C may be that reaction time, ozone flow, sulfuric acid concentration are 3.5 hours, 80 ml/min and 98 wt_. %, respectively. X-ray diffraction (XRD) patterns were used to analyze the structure and confirmed that GIC had indeed been prepared successfully. Scanning electron microscope (SEM) images showed the morphologies of GIC and exfoliated graphite (EG).

Abstract: Interdigitated back contacted (IBC) silicon solar cells have long been shown as high conversion efficiency solar cells, with values as high as 25.0% reported by Sunpower [1]. Such high efficiencies are enabled by the cell structure, with the absence of front side metal shading, which can then be optimised from optical and passivation perspectives. High bulk lifetime silicon and a low series resistance metallisation scheme can also enhance the efficiencies. Other advantages include the easier module incorporation given both metal contacts are located on the rear of the cell.

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Abstract: This paper deals with experimental investigations related to removal of manganese (II) from electrolytic manganese residues by using ozone as oxidant. Ozone was used in this study to oxidize manganese converting bivalent manganese to high valence states, the oxidized salts will precipitate as manganese oxides, that to reach the concentration of the pollutant under its limit values in water. Effects of reaction temperature, reaction contact time and initial pH value on the manganese (II) removal were investigated. The results indicated that the removal rate exceeded 99.9 percent, and the manganese (II) in solution was lower than 0.1 mg·L^-1 under the conditions of reaction temperature 45 °C, reaction contact time 40 min and initial pH 12.