Assessment of the level of pollution of water bodies of the Denezhkin kamen reserve by the Shemur field

Waste produced during the extraction of minerals can cause various environmental problems. One of which is polluting underground and surface waters. The purpose of the article is to assess the level of pollution of water bodies of the Denezhkin Kamen reserve by the Shemur ore field. To assess the level of pollution, individual and complex pollution indices, statistical parameters and the ʺQuartileʺ method for calculating emissions are used. An analysis of the geological structure of the territory and physical and geographical conditions of the area was carried out; the level of pollution was assessed; the main causes of pollution were determined; the main pollutants were identified. The waters flowing through the reserve are not polluted they are polluted near the reserve borders. Pollutants are carried downstream over long distances and get into the intakes of local settlements. In the Bannaya River basin, the pollution area is about 80 km; in the Olkhovka River basin, the pollution area is about 60 km. There is a dependence in the change in the concentration of pollutants on seasonality and weather conditions. The main pollutants are those that are contained in large quantities in the overburden rocks of the deposit. Additional studies are required using a sampling program, which was not available during the current studies.

The synergistic photocatalytic effects of surface-modified g-C3N4 in simple and complex pollution systems based on a macro-thermodynamic model

The novelty of this paper is the construction of a macro-thermodynamic model based on the synergistic photocatalytic effects of surface-modified g-C3N4.

Analysis of Compositional Variation and Source Characteristics of Water-Soluble Ions in PM2.5 during Several Winter-Haze Pollution Episodes in Shenyang, China

From 18 February to 13 March 2014 and from 17 December 2016 to 27 January 2017, an online analyzer for monitoring aerosols and gases (MARGA) and an online single particle aerosol mass spectrometer (SPAMS) were used to measure and analyze the concentrations and sources of water-soluble (WS) ions in PM10, PM2.5, and gases (NH3, HNO3, HCl), in Shenyang City, China. During the field campaign, nine haze episodes (or smog episodes, total 582 h) were identified, with 960 identified as non-haze periods. The average mass concentrations of PM2.5 and total water-soluble ions (TWSIs) in PM2.5 during haze episodes were 131 μg·m−3 and 77.2 μg·m−3, 2.3 times and 1.9 times the values in non-haze periods, respectively. The average mass concentration of TWSIs in PM2.5 was 55.9 μg·m−3 (accounting for 55.9% of PM2.5 mass loading), 37.6% of which was sulfate, 31.7% nitrate, 20.0% ammonium, 6.6% chloride, 1.9% potassium, 1.4% calcium, and 0.8% magnesium throughout the campaign. Concentrations of sulfate, nitrate, and ammonium (SNA) secondary pollution ions increased rapidly during haze episodes to as much as 2.2 times, 3.0 times, and 2.4 times higher than during non-haze periods, respectively. Diurnal variations during non-haze periods were significant, while complex pollution was insignificant. Based on changes in the backward trajectories and concentrations of WS ions, the hazy episodes were divided into three types: complex, coal-burning, and automobile exhaust pollution. All complex episodes had high concentrations and greater contributions of ammonium nitrate from complex and automobile exhaust pollution, while the contribution of ammonium sulfate from coal-burning pollution was greater than that of ammonium nitrate. The correlation coefficients among SNA species were very high in complex pollution, with nitrate and sulfate the main forms present. The results of principal component analysis (PCA) were related to emissions from burning coal for heating and from long-range transmission in winter. In the case of exhaust pollution, NO3− accounted for the highest percentage of PM2.5, and NH4+ was more closely related to NO3− than to SO42−. Coal-burning pollution was the most common type of pollution in Shenyang. The contribution of sulfate was higher than that of nitrate. Based on PCA, the contribution of coal-burning emissions varied from 36.7% to 53.6% due to industry, soil sources, and other factors.