Preliminary Study on the Emission Rules of Sulfur Derivative Pollutants in Putrefactive Cyanobacteria

[Objective]The aim was to study the characteristics of the emission of sulfur derivative pollutants in cyanobacteria.[Method]Based on water odor in drink water from Gonghu Bay in Lake Taihu,the sulfur derivatives pollutants were extracted by head space solid phase microextraction（HS-SPME） and the odor substance was identified by gas chromatography and mass spectrometry（GC-MS）.Decomposed simulation was conducted in closed tube of water and cyanobacteria samples collected from Gonghu Bay in Lake Taihu.The cyanobacteria rotten odor substances was analyzed and detected by HS-SPME-GC-MS for 10 days.The sulfur derivative pollutant was expounded.[Result]The primary or secondary metabolites by cyanobacteria in water samples such as β-cyclocitral,indol,methylphenol,mercaptan and thioether were detected with scan.During the decomposition process,the emission of β-cyclocitral changed little.The maximum emission of dimethyl trisulfide appeared on the seventh and eighth day.The maximum emission of dimethyl disulfide appeared on the forth day.The maximum emission of the diethyl sulfide was on the eighth and ninth day.The maximum concentration of dimethyl trisulfide was 2 344.79 ng/L,which was much more than the olfactory threshold.[Conclusion] The sewage in Gonghu Bay in the end of May in 2007 resulted from the accumulation of cyanobacteria.

Immigration,transformation,and emission control of sulfur and nitrogen during gasification of MSW:Fundamental and engineering review

This paper proposes a comprehensive summary and analysis of an important issue during municipal solid waste(MSW)gasification-sulfur and nitrogen pollution.It provides an overview of the fundamentals of MSW and the basic aspects of nitrogen and sulfur elements.Their characteristics of immigration,transformation and distribution during gasification with control solutions in realized or potential engineering are also concluded.The analysis indicates that the complete scenario of the occurrence form of sulfur and nitrogen elements in MSW is difficult to obtain,owing to the diverse sources and complicated compositions.However,with the assistance of advanced characterization and quantification methods(XPS,XRD,TG-FTIR,et al.),the common sulfur-and nitrogen-containing compounds in both organic and inorganic states can be detected.Adjustment of gasification conditions can regulate the transformation of these elements for emission control.The multiple pollutants including H_(2)S,SO_(x),COS,NH_(3),HCN and NO_(x)cannot be eliminated by one-step treatment but a combination of adsorption and catalytic treatments may realize the control goal.This research aims to benefit meeting emission standards during MSW gasification and to provide a reference for other processes such as incineration,pyrolysis and other feedstocks like biomass and refuse derived fuel(RDF).

Efectiveness of national air pollution control policies on the air quality in metropolitan areas of China

Understanding the effectiveness of national air pollution controls is important for control policy design to improve the future air quality in China. This study evaluated the effectiveness of major national control policies implemented recently in China through a modeling analysis. The sulfur dioxide （SO2） control policy during the llth Five Year Plan period （2006-2010） had succeeded in reducing the national SO2 emission in 2010 by 14% from its 2005 level, which correspondingly reduced ambient SO2 and sulfate （SO42-） concentrations by 13%-15% and 8%-10% respectively over east China. The nitrogen oxides （NOx） control policy during the 12th Five Year Plan period （2011-2015） targets the reduction of the national NOx emission in 2015 by 10% on the basis of 2010. The simulation results suggest that such a reduction in NOx emission will reduce the ambient nitrogen dioxide （NO2）, nitrate （NO3-）, 1-hr maxima ozone （03） concentrations and total nitrogen deposition by 8%, 3%-14%, 2% and 2%--4%, respectively over east China. The application of new emission standards for power plants will further reduce the NO2, NO3-, 1-hr maxima 03 concentrations and total nitrogen deposition by 2%-4%, 1%-%, 0-2% and 1%-2%, respectively. Sensitivity analysis was conducted to evaluate the inter-provincial impacts of emission reduction in Beijing-Tianjin-Hebei and the Yangtze River Delta, which indicated the need to implement joint regional air pollution control.