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The abundance of Peptostreptococcaceae increased even the temperature was lower than 10℃, which typically increases VFA production. Therefore, the concentrations of effluent VFA and TCOD increased, but methane production decreased. The effluent concentration of SCOD was relatively stable. The microbial abundance and diversity were the richest at 19℃ in the reactor. The acetolactic methanogens were the dominant methanogens at low temperatures. The anaerobic biological filter for the treatment of urban sewage starts quickly and can resist the impact of continuous temperature reduction. Moreover, it does not need backwashing after running for nine months, and it is not easily clogged.Therefore,the functions of biological contact oxidation and filtration retention of the biological filter can be more fully utilized.Naphthalene sulfonic acid is widely used in the industry. In this study, H acid (1-amino-8-naphthol-3,6-disulfonic acid) was selected as the characteristic pollutant, and the alkali-activated, thermally-activated, and alkali-heat-complex activated persulfate (PS) degradation of H acid was analyzed. The effects of other factors on complex activation were discussed. The experimental results showed that with the addition of calcium oxide from 0 to 1250 mg ·L-1, the H acid removal rate increased from 42.5% to 82.8% after 100 min of reaction. The removal rate of H acid in thermal activation is positively correlated with temperature. The removal rate of H acid at 65℃ is 77.5%, and the apparent activation energy is 37.85 kJ ·mol-1. Although composite activation speeds up the reaction rate, rapid degradation of PS at high temperatures caused the degradation of H acid to be worse than single thermal activation. The change in PS concentration did not significantly improve the removal rate of H acid, and the inorganic anion CO32- was not conducive to the removal of H acid. Compound activation is not ideal for the mineralization of H acid, and the removal rate of TOC is only 16%. GC-MS identified the degradation product of H acid as terephthalic acid, indicating that phthalic anhydride may be formed after the naphthalene ring is opened.The adsorption performance of three iron ores (pyrite, hematite, and magnetite) on Sb(Ⅴ) was compared and pyrite was shown to exhibit the highest adsorption performance. The effects of particle size, concentration, and pH on the adsorption performance were investigated with pyrite as the absorbent. The rejection of Sb(Ⅴ) was the highest (>80%) when pyrite (particle size less then 0.074 mm) was used as the absorbent with a concentration of 1 g ·L-1 and pH=7. The ion competition experiment indicated that PO43- can inhibit the adsorption of Sb(Ⅴ), while SO42- and CO32- have no significant effects on the adsorption of Sb(Ⅴ) because PO43- can compete with Sb(Ⅴ) for active adsorption sites on the surface of pyrite. The results also showed that the quasi-second-order kinetic model and Langmuir model can better simulate the adsorption process, which shows a single-layer adsorption behavior and chemisorption plays a main role in the rejection of Sb(Ⅴ). FTIR analysis suggested that the removal of Sb(Ⅴ) by pyrite was a coordinated ion exchange reaction. EDS and XPS results further confirmed that Sb(Ⅴ) was adsorbed on the surface of pyrite and was not reduced to Sb(Ⅲ), which is more toxic.Most sponge city constructions in China are carried out in urban parcel-based catchments, and the quality and quantity of surface runoff can be controlled by several low impact development (LID) facilities. However, there are few reports on the generation and control of urban diffuse pollution. In this study, two areas with different hardening rates were compared to analyze the load conditions during the accumulation-wash-off-transport process of particulate pollutants. The results showed that the road surface in the catchment was the main underlying surface that the particulate pollutants contributed to. The road dust accumulation in the medium hardening rate (61.1%) and high hardening rate (73.6%) plots accounted for 88.4% (2.22-12.51 g ·m-2) and 90.1% (4.99-33.43 g ·m-2) of the catchment area unit, respectively. The contribution to the suspended solids (SS) load of runoff was 91.7% (0.97-7.34 g ·m-2) and 90.5% (0.92-18.77 g ·m-2), respectively. The SS load of road runoff accounted for approximately 95.2% and 83.1%, respectively. The pollution load (SS) after treatment by the LID facilities was approximately 24.0% and 40.2% of the surface runoff, respectively. selleckchem The particle size distribution of road dust during the accumulation and wash-off processes was>150 μm, while that in surface and output runoff was 1000 μm 58.1%, 108.5%; 250-450 μm 72.9%, 41.8%; less then 45 μm 59.2%, 64.8%). The results revealed the entire distribution process (accumulation-wash-off-transport) of particulate pollutants and the effect of LID facilities on the total SS pollution load of the catchment, which can provide an important reference for the scientific assessment of the project performance of LID installation in urban parcel-based catchments.A field-scale dry grass swale with impermeable bottom and shallow substrate layer was built in Shanghai, where the groundwater table is very high, to avoid groundwater pollution caused by runoff infiltration. The underdrain pipe of the facility was up bended to avoid outside water flowing backward because local ground elevation is very low. Performance of the facility under the actual precipitation conditions was evaluated in the rainy season of 2019. The average runoff volume reduction is 39.4%, and the peak flow is reduced effectively when rain intensity is lower than 8.0 mm ·h-1. Influent mass load reduction of TSS, COD, TP, and TN are 95.4%, 83.1%, 90.0%, and 57.7%, respectively. Wood chips in the substrate layer and the saturated zone are effective for denitrification during the wet and dry periods, respectively. Hydraulic loading rate and antecedent drying period are the main factors affecting denitrification. Improved influent quality combined with the storage volume supplied by the local urban river network could meet the goal of annual runoff volume reduction and annual pollution load removal in districts with high groundwater levels.

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