Time filter

Source Type

Zhang H.,Hefei University of Technology | Zhang H.,Anhui Institute of Environment Science | Liu G.,Hefei University of Technology | Mei J.,Tongling Environment Observatory | And 2 more authors.
Journal of University of Science and Technology of China | Year: 2014

Using the monitoring data of atmospheric pollution and meteorological data from 2007 to 2010, the concentration diurnal variations of atmospheric pollutants (including SO2, NO2 and PM10) in Tongling City were analyzed, and the relationship between the diurnal variations of atmospheric pollutants and meteorological factors was studied. The results show that the diurnal variations of atmospheric pollutant concentrations and meteorological factors can be classified into two types, "single pink and single valley type" and "double pinks and double valleys type". There is no spatial variation in SO2 and PM10 , while NO2 exhibited obvious spatial variation. For areas near the pollution source, pollutant concentration is correlated with atmospheric pressure, relative humidity and temperature, but not with wind speed. For the observation points free from pollutants, the relationship of pollution concentration variation and meteorological factors is similar to the area near the pollution source, and the pollution concentration variation is reversely correlated with wind speed. The other observation points of Tongling City, which are not included in the two, showed little relationship between pollutant concentration variation and meteorological factors.

Lang L.,Hefei University of Technology | Zhang L.,Anhui Institute of Environment Science | Zhang L.,Tongji University | Zhu Y.,Hefei University of Technology | And 4 more authors.
Research of Environmental Sciences | Year: 2013

Electrocoagulation with stainless steel electrodes and aluminum electrodes were adopted for removal of ammonia nitrogen and phosphorus. The thermodynamics, kinetics and the effect of different parameters on ammonia nitrogen and phosphorus removal were studied. The results showed that stainless steel electrode were more suitable for removal of ammonia nitrogen and phosphorus from aqueous solutions compared with aluminum electrodes. The phosphorus adsorption process could be depicted primarily by Redlich-Peterson function and the higher temperature was helpful for its adsorption, which was a spontaneous and endothermal process. The changes of Gibbs free energy ranges from-20 kJ/mol to 0 kJ/mol. The correlation coefficient R2 was greater than 0.98, and this indicated that the kinetic data of phosphorus adsorption were better fitted with the pseudo-second-order kinetic model. The removal efficiency of ammonia nitrogen and phosphorus increased with increasing electric current density. A lower ammonia nitrogen removal rate under strong alkaline conditions was also observed, and the removal efficiency of phosphorus was the best under acid conditions, while it decreased with the increasing pH. The power values were 0.15-0.50 and 0.02-0.04 kW·h/g respectively, which were required for ammonia nitrogen and phosphorus removal during electrochemical processes.

Feng J.,Hefei University of Technology | Zhang L.,Anhui Institute of Environment Science | Sun Y.,Nanjing University | Yan Y.,Anhui University
Proceedings - International Conference on Computer Distributed Control and Intelligent Environmental Monitoring, CDCIEM 2011 | Year: 2011

A new kind of self-aeration subsurface constructed wetland system was designed. The self-aeration mechanism of self-aeration subsurface constructed wetland system was discussed in detail. The experimental results indicated that the self-aeration and denitrification effect of the system was perfect. The dissolved oxygen of the synthetic wastewater was around 1 mg/L, and it increased to 3 mg/L after the selfaeration system, which explained the perfect self-aeration ability of this system. Furthermore, the concentration of dissolved oxygen in and out of the self-aeration subsurface constructed wetland was 0.5-1.0 mg/L and around 2.0 mg/L, respectively. Meanwhile, the denitrification efficiency was enhanced greatly with the maximum denitrification efficiency of 82.2%. © 2011 IEEE.

Zhang H.,Anhui Institute of Environment Science | Huang Y.,Anhui Institute of Meteorology | Li K.,Anhui Institute of Environment Science
Huanjing Kexue/Environmental Science | Year: 2012

This article used the remote sensing data from 2002 to 2007 obtained by NOAA/AVHRR to analyze the relationship between algae bloom and lake surface bright temperature in Chaohu Lake. The spatial distribution of Chaohu Lake surface bright temperature was found to be similar to that of the occurrence frequencies of algae bloom. Algae blooms occurred frequently in the region with high bright temperature. In terms of temporal distribution, there was significant difference between the bright temperature and algae bloom, which indicated that the algae bloom could be affected by factors other than the temperature. From the analysis, the following conclusions were drawn. First, the break out season of algae bloom could be divided into spring and summer periods in annual variation, with May as the dividing point. In the spring break out season, the growth and propagation of algae did not depend on the temperature of water, and the affected areas of algae bloom were usually small. Secondly, with the increase of precipitation in July, the bright temperature and the occurrence frequency of algae bloom were decreased.

Loading Anhui Institute of Environment Science collaborators
Loading Anhui Institute of Environment Science collaborators