Characteristics of PM and PAHs emitted from a coal-fired boiler and the efficiencies of its air pollution control devices.

Sampling and analysis of filterable particulate matter (FPM), FPM, condensable particulate matter (CPM), polycyclic aromatic hydrocarbons (PAHs), sulfur oxides (SO), and nitrogen oxides (NO) emitted from a coal-fired boiler equipped with selective catalytic reduction (SCR)+ electrostatic precipitator (ESP) + wet flue gas desulfurization (WFGD) + wet electrostatic precipitator (WESP) as air pollution control devices (APCDs) are conducted. The results show that NO concentration emitted from the coal-fired boiler is 56 ± 2.17 ppm (with the NO removal efficiency of 47.

Characteristics and separation efficiencies of PPSU/PEI/PEG blend membranes with different compositions for water treatment.

To overcome the problems and constraints in the application of single organic membranes in wastewater treatment or water reuse processes, different blend membranes were prepared and modified to improve the separation efficiency of humic acids (HAs) and mitigate the fouling problems occurring during water purification. This study extends the results of our previous research and further investigates the relationships between the composition of polyphenylsulfone/polyetherimide/polyethylene glycol (PPSU/PEI/PEG) blend membranes and membrane characteristics and performance. The experimental results showed that the PEI and PEG component ratios of PPSU could significantly affect the blend membrane structure, morphology, and properties.

Removals of fly ash and NO in a fluidized-bed reactor with CuO/activated carbon catalysts.

This study investigates the effects of fly ash compositions (SiO(2) and Al(2)O(3)), particle sizes (4-10 μm and 40 μm), and concentrations on the simultaneous removals of fly ash and NO using a fluidized-bed catalyst reactor. Experimental results show that the removal efficiencies of fly ash and NO at particle concentrations of 968-11,181 mg m(-3) are 71-97% and 42-57%, respectively. SiO(2) particles have more influences than Al(2)O(3) particles on the performances of fluidized-bed CuO/AC catalyst.

Partitioning characteristics and particle size distributions of heavy metals in the O2/RFG waste incineration system.

This study applies the oxygen/recycled flue gas (O(2)/RFG) combustion technology for waste incineration and investigates the effects of different RFG rates on the concentrations of gas pollutants as well as the partitioning characteristics and particle size distributions of five heavy metals (Cr, Cu, Pb, Zn, and Cd). Experimental results show that the combustion efficiency can be improved and the concentration of CO(2) is increased by appropriately controlling the RFG rate in the O(2)/RFG incineration system. The partitioning characteristics and size distributions of heavy metals in O(2)/RFG combustion system are different from those in general air combustion system.

Effects of particulates, heavy metals and acid gas on the removals of NO and PAHs by V2O5-WO3 catalysts in waste incineration system.

This study investigated the activities of prepared and commercial V(2)O(5)-WO(3) catalysts for simultaneous removals of NO and polycyclic aromatic hydrocarbons (PAHs) and the influences of particulates, heavy metals, SO(2), and HCl on the performances of catalysts. The experiments were carried out in a laboratory-scale waste incineration system equipped with a catalyst reactor. The DREs of PAHs by prepared and commercial V(2)O(5)-WO(3) catalysts were 64% and 72%, respectively.

Effects of sodium modification, different reductants and SO(2) on NO reduction by Rh/Al(2)O(3) catalysts at excess O(2) conditions.

Although many catalysts of NO reduction have been developed, the presence of excess O(2) and SO(2) significantly inhibits their performance when they are used to treat the incineration flue gas. To solve such problem, this study prepared new Rh/Al(2)O(3) catalysts and investigated the effects of Na modification, SO(2) and different reductants. Experimental results indicated that the average removal efficiency of NO at such high O(2) concentrations exceeded 80% when the Rh/Al(2)O(3) catalysts were used.

Emission characteristics of coal combustion in different O2/N2, O2/CO2 and O2/RFG atmosphere.

This study investigates the emission characteristics of CO(2), SO(2) and NOx in the flue gas of coal combustion by varying the compositions and concentrations of feed gas (O(2)/CO(2)/N(2)) and the ratios of recycled flue gas. The differences between O(2)/recycled flue gas (O(2)/RFG) combustion and general air combustion are also discussed. Experimental results indicate that the maximum concentration of CO(2) in O(2)/CO(2) combustion system is 95% as the feed gas is 30% O(2)/70% CO(2).

Preparation and application of granular ZnO/Al2O3 catalyst for the removal of hazardous trichloroethylene.

Trichloroethylene (TCE) is a volatile and nerve-toxic liquid, which is widely used in many industries as an organic solvent. Without proper treatment, it will be volatilized into the atmosphere easily and hazardous to the human health and the environment. This study tries to prepare granular ZnO/Al(2)O(3) catalyst by a modified oil-drop sol-gel process incorporated the incipient wetness impregnation method and estimates its performance on the catalytic decomposition of TCE.

Prediction for energy content of Taiwan municipal solid waste using multilayer perceptron neural networks.

In the past decade, the treatment amount of municipal solid waste (MSW) by incineration has increased significantly in Taiwan. By year 2008, approximately 70% of the total MSW generated will be incinerated. The energy content (usually expressed by lower heating value [LHV]) of MSW is an important parameter for the selection of incinerator capacity.

Characteristic of polycyclic aromatic hydrocarbon concentrations and source identification for fine and coarse particulates at Taichung Harbor near Taiwan Strait during 2004-2005.

Fine (PM(2.5)) and coarse (PM(2.5-10)) particulate concentrations of ambient air polycyclic aromatic hydrocarbons (PAHs) were measured simultaneously from February 2004 to January 2005 at the Taichung Harbor (TH) sampling site near Taiwan of central Taiwan.

Concentrations of ambient air particulates (TSP, PM2.5 and PM2.5-10) and ionic species at offshore areas near Taiwan Strait.

The concentrations of total suspended particulate (TSP), fine particles PM(2.5) (with aerodynamic diameter <2.5 microm), coarse particles PM(2.

Characteristic study of polycyclic aromatic hydrocarbons for fine and coarse particulates at Pastureland near Industrial Park sampling site of central Taiwan.

The concentrations of ambient air polycyclic aromatic hydrocarbons were measured in a farm area (Tunghai University Pastureland) between August 2001 and April 2002 in central Taiwan, Taichung. Particle-bound polycyclic aromatic hydrocarbons (PAHs) were collected on quartz filters, the collected sample was extracted with a dichloromethane (DCM)/n-hexane mixture (50/50, v/v) for 24 h, and then the extracts were subjected to gas chromatography-mass spectrometric analysis. The PM2.

Metallic elements study on fine and coarse particulates during daytime and nighttime periods at a traffic sampling site.

Fine (PM2.5) and coarse (PM(2.5-10)) particulates were collected simultaneously by using a versatile air pollutant system at a traffic sampling site during daytime and nighttime sampling periods during August 2003 to March 2004.

Removal of carbon dioxide by a spray dryer.

With the global warming due to greenhouse effects becoming serious, many efforts are carried out to decrease the emissions of CO2 from the combustion of carbonaceous materials. In Taiwan, there are 19 large-scale municipal solid waste incinerators running and their total emission of CO2 is about 16,950 kton y-1. Spray dryer is the most prevailing air pollution control devise for removing acid gas in waste incineration; however, the performance of spray dryer on the removal of CO2 is seldom studied.

Catalytic oxidation of organic compounds in incineration flue gas by a commercial palladium catalyst.

The object of this study is to investigate the effect of different operation conditions on the catalytic oxidation of trace organic compounds [i.e., benzene, toluene, ethylbenzene, and xylene (BTEX); and polyaromatic hydrocarbons (PAHs)] in incineration flue gas.

The Effects of Chloride Additives on Adsorption of Heavy Metals during Incineration.

The dynamic adsorption behaviors and characteristics of heavy metals on a sorbent at different temperatures have been investigated in a previous study by the same authors. The present work focuses on the dynamic adsorption behaviors of Cr, Cu, Pb, and Cd on a sorbent (silica sand with limestone) under various chloride additive conditions (no chloride; an organic chloride, polyvinyl chloride [PVC]; and an inorganic chloride, sodium chloride [NaCl]), and estimates the adsorption saturation point of the sorbent during fluid-ized-bed incineration. The results will enable us to evaluate the effects of various chloride additives on the adsorption efficiency of heavy metals and to determine when the sor-bents should be renewed.

Influence of Operating Conditions on the Formation of Heavy Metal Compounds During Incineration.

The formation of Cr, Pb, and Cd species under various operating conditions in a pilot-scale fluidized-bed incinerator was investigated. Examined were the effects of (1) an organic chloride (PVC) additive, (2) an inorganic chloride (NaCl) additive, and (3) NaNO and PVC additives, under various operating temperatures. Two-stage modeling was performed to match the actual incineration conditions of the current study.