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The UASB reactor was used to reconstruct leachate treatment project of Beijing Asuwei Waste Sanitary Landfill Site, and the commissioning with the UASB reactor was executed. Water quality indicators were determined in the debugging process, and the results showed that the VFA content in the anaerobic tank was controlled within 600 mg/L, which indicated that the water quality did not have the acidified phenomenon. The COD removal efficiency was 50% approximately and NH3-N concentration showed as light decline when operation stability in anaerobic system. [ABSTRACT FROM AUTHOR]

Seasonal dependence of the columnar aerosol optical and chemical properties on regional transport in Beijing over 10 years (from January 2005 to December 2014) were analyzed by using the ground-based remote sensing combined with backward trajectory analysis. Daily air mass backward trajectories terminated in Beijing were computed with HYSPLIT-4 model and were categorized into five clusters. The columnar mass concentrations of black carbon (BC), brown carbon (BrC), dust (DU), aerosol water content (AW), and ammonium sulfate like aerosol (AS) of each cluster were retrieved from the optical data obtained from the Aerosol Robotic NETwork (AERONET) with five-component model. It was found that the columnar aerosol properties in different seasons were changed, and they were related to the air mass origins. In spring, aerosol was dominated by coarse particles. Summer was characterized by higher single scattering albedo (SSA), lower real part of complex refractive index ( n ), and obvious hygroscopic growth due to humid air from the south. During autumn and winter, there was an observable increase in absorption aerosol optical thickness (AAOT) and the imaginary part of complex refraction ( k ), with high levels of retrieved BC and BrC. However, concentrations of BC showed less dependence on the clusters during the two seasons owing to the widely spread coal heating in north China. [ABSTRACT FROM AUTHOR]