Dry deposition samples were collected in a weekly basis during 2010 in a site located at the Mexican Pacific Coast: Manzanillo, Colima. Samples were collected with an automatic wet/dry deposition sampler using nylon f...Dry deposition samples were collected in a weekly basis during 2010 in a site located at the Mexican Pacific Coast: Manzanillo, Colima. Samples were collected with an automatic wet/dry deposition sampler using nylon filters as surrogate surfaces. Samples were extracted with deionized water and analyzed for pH, conductivity, Na+, K+, Ca2+, Mg2+, NH4-, NO3-, SO42- and Cl-. Nitrate and sulfate were the most abundant ions, contributing with 53% to the total ionic mass;and their levels exceeded the hemispheric background concentrations proposed for marine remote sites. The influence of the power plants burning combustoleo located upwind the sampling site was completely evident. From meteorological analysis, it could be observed that the sampling site was all time under the influence of power plants as a result of the effect of breezes. However, in spite of the high levels of NO3- and SO42- found in the samples collected, pH value average was almost neutral, with 28% of samples slightly acid. Potassium was the most abundant cation and from the quantification of the neutralization effect of the main alkaline components, the prevalence role of K+ was completely evident, suggesting the influence of the mining complex Pe?a Colorada located upwind the sampling site, where amyl xanthate potassium is used as collector in tailing dams. Dry deposition fluxes were estimated for all ions measured. Nitrogen dry deposition at Manzanillo is already in the upper extreme of the threshold value reported for sensible ecosystems. On the other hand, sulfur deposition exceeded slightly the critical load value reported for some ecosystems in Europe. Even at this moment, nitrogen and sulfur deposition is not a problem, it is necessary to take steps to avoid that total deposition of these elements exceeds critical loads, considering that results reported in this study not include the wet deposition fluxes.展开更多
The basic methods of concentration and purification of liquid radioactive waste on the nuclear power plant are distillation and ionic exchange. During vaporization of oil waste products and the fulfilled washing solut...The basic methods of concentration and purification of liquid radioactive waste on the nuclear power plant are distillation and ionic exchange. During vaporization of oil waste products and the fulfilled washing solutions the part of oil passes into a condensate. Clearing of such condensate on ion-exchanged filters results to oiling of ion-exchanged materials and to decrease number of filter cycles. Due to the often regeneration of ion-exchanged filters additional volumes of waste products as the fulfilled reclaiming solutions, washing and loosening waters are formed. The attention of scientists was involved with methods of clearing of water environments from the organic substances, based on deep oxidizing transformations of hydrocarbons into carbonic gas and water. From processes of oxidation of hydrocarbons up to CO2 and H2O, sold at moderate conditions, our attention has involved photochemical oxidation with the help of UV-radiation.展开更多
文摘Dry deposition samples were collected in a weekly basis during 2010 in a site located at the Mexican Pacific Coast: Manzanillo, Colima. Samples were collected with an automatic wet/dry deposition sampler using nylon filters as surrogate surfaces. Samples were extracted with deionized water and analyzed for pH, conductivity, Na+, K+, Ca2+, Mg2+, NH4-, NO3-, SO42- and Cl-. Nitrate and sulfate were the most abundant ions, contributing with 53% to the total ionic mass;and their levels exceeded the hemispheric background concentrations proposed for marine remote sites. The influence of the power plants burning combustoleo located upwind the sampling site was completely evident. From meteorological analysis, it could be observed that the sampling site was all time under the influence of power plants as a result of the effect of breezes. However, in spite of the high levels of NO3- and SO42- found in the samples collected, pH value average was almost neutral, with 28% of samples slightly acid. Potassium was the most abundant cation and from the quantification of the neutralization effect of the main alkaline components, the prevalence role of K+ was completely evident, suggesting the influence of the mining complex Pe?a Colorada located upwind the sampling site, where amyl xanthate potassium is used as collector in tailing dams. Dry deposition fluxes were estimated for all ions measured. Nitrogen dry deposition at Manzanillo is already in the upper extreme of the threshold value reported for sensible ecosystems. On the other hand, sulfur deposition exceeded slightly the critical load value reported for some ecosystems in Europe. Even at this moment, nitrogen and sulfur deposition is not a problem, it is necessary to take steps to avoid that total deposition of these elements exceeds critical loads, considering that results reported in this study not include the wet deposition fluxes.
文摘The basic methods of concentration and purification of liquid radioactive waste on the nuclear power plant are distillation and ionic exchange. During vaporization of oil waste products and the fulfilled washing solutions the part of oil passes into a condensate. Clearing of such condensate on ion-exchanged filters results to oiling of ion-exchanged materials and to decrease number of filter cycles. Due to the often regeneration of ion-exchanged filters additional volumes of waste products as the fulfilled reclaiming solutions, washing and loosening waters are formed. The attention of scientists was involved with methods of clearing of water environments from the organic substances, based on deep oxidizing transformations of hydrocarbons into carbonic gas and water. From processes of oxidation of hydrocarbons up to CO2 and H2O, sold at moderate conditions, our attention has involved photochemical oxidation with the help of UV-radiation.
