[Emission Characteristics of Residential Coal Combustion Flue Gas in Beijing].

Honeycomb briquet,biomass briquettes and bituminous coal from suburb of Beijing were chosen as testing samples to carry out combustion experiments. The characteristics of inorganic pollutant emission factors and VOCs emission factors released from the flue gas were studied. The results showed that under the condition of sufficient combustion, the average emission factors of SO from these three types of coal respectively were 1.

[Correlation between acidic materials and acid deposition in Beijing during 1997-2011].

Based on the environment monitoring data and the ambient air quality data during the period of 1997-2011 from Beijing municipal environmental monitoring center, the correlations between primary pre-cursors of acid deposition, acidic materials and precipitation in Beijing area were analyzed in detail by taking economic development and energy mix into account. These results will be helpful for assessing the performance of environment quality improvement, as well as supplying scientific supporting information to make policies for national and local environment protection authorities. The main findings included as follows: there are significant correlations between the concentrations of NO2, NOx, and SO2 in the atmosphere, which indicated that both N and S in ambient air of Beijing came from fossil fuels combustion; acidic pollutants in the air are mainly discharged from local emission sources in Beijing, while there is no obvious correlation between S and N in wet deposition and concentrations of SO2, NO2 and NOx in the atmosphere, which demonstrated that concentrations of different ions in the acid deposition were influenced by both local sources as well as the inputs from other surrounding districts.

[Characteristics of chemical compositions of precipitation in Beijing].

Characteristics of chemical compositions of precipitation in Beijing were analyzed. The average value of pH was 5.19 from 2005 to 2009, showing stable characteristics of acidification with precipitation.