Sometimes nocturnal ozone maxima have been observed, contrasting with the nocturnal minimum values of typical daily profile. The influence of land-sea breeze on the nocturnal ozone maxima was analysed in two urban sites strongly influenced by traffic emissions. Results showed that the increase in nocturnal ozone concentration, as well as its maxima was caused by horizontal advection of ozone, associated with the development of land-sea breezes. This conclusion, obtained considering 18 months of two years, is in agreement with the only previous study that analysed the influence of land-sea breeze, but considering simply the four warmest months of one year.
- Inderscience Publishers
- Influence of land-sea breezes on nocturnal ozone maxima observed ...
Fluorinated greenhouse gases 2015
Summary of data reported by companies on the production, import and export of fluorinated greenhouse gases in the European Union Background and policy International policy The greenhouse gases addressed by the United Nations Framework Convention on Climate Change (UNFCCC) include several groups of fluorinated gases, the so-called F-gases. Hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulphur hexafluoride (SF6) and nitrogen trifluoride (NF3) are covered by the Kyoto Protocol and are also included in the...
Case study - Pure oxygen injection into a pipeline. Hagerstown, Maryland
The Problem: In 2010, the Hagerstown Wastewater Treatment Plant in Maryland incorporated several plant modifications, one of which was the conversion of their disinfection process from the use of ozone to that of ultraviolet (UV). In their previous system, due to the ozone being produced by an oxygen-fed ozone generator, the dissolved oxygen (DO) levels of the effluent being discharged into a local creek met regulatory standards. With the change in the disinfection process, the regulatory agency was concerned...
Case study - Mazzei degas separator selected for Wichita aquifer storage and recovery project
GDT Degas Separator Selected As Best Method For Entrained Gas Bubbles Removal Wichita, KSThe Problem: In the 1990s, the City of Wichita, Kansas developed a water supply plan that included creating a sustainable water supply through the year 2050. The key component of the plan is recharging the large aquifer that lies under the region with 100 MGD of water from the Little Arkansas River. This undertaking is known as the Aquifer Storage and Recovery project or ASR. Phase I was completed in 2006 with the diversion...
Case study - City of Montreal upgrade of Atwater and Des Baillets water treatment plants
Sidestream Venturi Injection—Basin Nozzle Manifold Contacting System. Montreal, Quebec, CanadaThe Problem: In 2001, a water quality audit revealed that two of the largest drinking water plants in the City of Montreal were out of compliance with Quebec’s latest water quality rules. In response to the audit, the city upgraded the 1,400 MLD Atwater and the 1,280 MLD Charles J. Des Baillets (Des Baillets ) Water Treatment Plants (WTPs) to comply with the water quality rules and meet the water quality...
Optimization of atmospheric air plasma for degradation of organic dyes in wastewater
This study optimises the degradation of a cocktail of the dyes methyl orange and bromothymol blue by atmospheric air plasma. Response surface methodology (RSM) was employed to investigate the efficacy of the plasma process parameters on degradation efficiency. A Box–Behnken design (BBD) was employed to optimise the degradation of dyes by air plasma discharge. A second order polynomial equation was proposed to predict process efficiency. It was observed that the predicted values are significant (p<0.001) with...