This study measured Ambient concentrations of air pollutants and Volatile Organic Compounds (VOCs) in industrial park in Kaohsiung City. The spatial distribution was investigated during different time periods and seasons. The ozone formation potential (OFP) of VOCs species were evaluated based on the maximum incremental reactivity (MIR). Also, this study using factor analysis to estimate the polluted source. The season distribution of air pollutants showed concentration in spring higher than summer, owing to air activities of summer are acute include wet precipitation, photochemical reaction, and convection. The time period distribution showed the results which NOx and O3 concentration occurred peaks at 7:00 − 8:00, 18:00 − 19:00 and 13:00 − 16:00, respectively. The reason is photochemical reaction, lead to concentration trend with time of NOx inversely to O3. The concentration trend with time of CO and PM10 similar to NOx. The polluted sources were estimated mobile. By the way, O3 is proportional to temperature, but it is Inversely proportional to humility. The seasons distribution of VOCs showed most abundant species included 2-butanone, toluene, and n-pentane in spring, while included toluene, acetone, m,p-xylene, and methyl methacrylate in summer. According to percent composition, most abundant categories in spring and summer were both aromatics, ketones, and alkanes. The TVOC concentration was spring (164.6 £gg/m3) higher than summer (116.4 £gg/m3). The time periods distribution of VOCs showed most abundant categories included aromatics and ketones in morning and evening, while included aromatics and alkanes in night. The TVOC concentration of evening (163.2 ¡Ó 62.7 £gg/m3) was highest, followed by night (159.9 ¡Ó 87.4 £gg/m3), Lowest was morning (98.4 ¡Ó 32.3 £gg/m3). Results showed alkanes and alkenes own higher concentration in night, ketones and esters in evening, and aromatics in evening and night. The reason is related with sunshine, inversion layer, and lower wind speed. By the way, TVOC is proportional to temperature. In spring, the OFP was 566.0 £gg-O3/m3, OFP/TVOC was 3.44. In summer the OFP was 629.3 £gg-O3/m3, OFP/TVOC was 5.41. It was worth mentioning highest OFP categories in spring and summer was both aromatics (332.2 £gg-O3/m3, 380.3 £gg-O3/m3), and highest OFP species was toluene (138.8 £gg-O3/m3) and methyl methacrylate (171.7 £gg-O3/m3) , respectively. The results from factor analyses showed the predominant source included mobile polluted source, petrol evaporation, related electronic industry, metallurgy industry, refinery, and architectural coatings escape in spring. The predominant source included mobile polluted source, petrol evaporation, plastic industry, steel industry, and related electronic industry in summer.

The emission of volatile organic compounds (VOCs) and odors from petrochemical industrial complex, including China Petroleum company (CPC),Renwu and Dazher petrochemical industrial parks, causes poor air quality of northern Kaohsiung. The removal efficiencies of elevated stacks and flares might play important roles on ambient air quality in metro Kaohsiung. Consequently, this study applied a tethered balloon technology to measure the vertical profile of VOCs, and ascertained their three dimensional dispersion in the atmosphere. The vertical profile of VOCs in ambient atmosphere surrounding the petrochemical industrial complex was measured during the intensive sampling periods (September 17-18th and December 20-21st, 2009 and April 8-9th and July 7-8th, 2010). Moreover, this study was designed to sample and analyze VOCs emitted from elevated stacks and flares, and estimate their emission factors. Finally, the source identification and ozone formation were further determined by principal component analysis (PCA) and ozone formation potential (OFP). This study found that some regions had relatively poorer air quality than other regions surrounding the petrochemical industrial complex. Most sampling sites with poor air quality were located at the downwind region of the petrochemical industrial complex, particularly with the prevailing winds blown from the northwest. Moreover, stratification phenomena were frequently observed at most sampling sites, indicating that high-altitude VOCs pollution should be considered for ambient air quality. This study revealed that the indicators of VOCs in northern Kaohsiung were toluene, C2 (ethylene+acetylene+ethane), and acetone. Vertical sampling of VOCs showed that the species of VOCs at the ground and high altitude were different, suggesting that ambient air quality at high altitude might be affected by the emission of VOCs from elevated stacks and flares at the petrochemical industrial complex. Results obtained from PCA showed that the major sources of VOCs in the ambient atmosphere of the petrochemical industrial complex were similar to the characteristics of VOCs emitted from the petrochemical industrial complex. The characteristics of VOCs at high altitude had strong correlation with petrochemical industry, indicating that the ambient air quality of northern Kaohsiung was highly influenced by the emission of VOCs from high stacks and flares. In addition, major VOCs for O3 formation potential at northern Kaohsiung were aromatics and vinyls, with particular species of toluene and C2. Moreover, air pollution episodes resulting from high O3 concentration was usually observed in early winter. Flare sampling results indicated that major VOCs emitted from the ground flare of CPC were alkanes and vinyls. The average removal efficiency of TVOCs was 98.2%. The average emission factor of VOCs was 0.0186 kg NMHC/kg flare gas. In addition, stack sampling results indicated that the emission factors of crude oil distillation process (P105), mixing process (P060), and rubber manufacturing process (P408) were 0.105, 1.11, and 61.97 g/Kl, respectively. The emission factor of P105 was lower than AP-42, while that of P408 was higher than AP-42.

Recently, restaurant employees exposing to cooking oil fume with potential lung cancer was highly concerned, indicating cooking oil fume emitted from restaurants might cause tremendous hazard to human health. This study combined photocatalytic oxidation and ozone oxidation technology to decompose VOCs from the exhaust of cooking oil fume from restaurants. Firstly, this study selected three different types of restaurants to implement air pollutant measurements in the indoor dinning room and stack emission. Indoor TVOCs continuous monitoring data showed that the highest TVOCs concentration was generally observed in the dining peak time. In this study, photocatalyst coated fiberglass filter was prepared by impregnation procedure and its characteristics was analyzed by SEM and XRD. Experimental results showed that the particle size of photocatalyst ranged from 25 to 50 nm and had high percentage of Anatase, suggesting that it had high photocatalytic reactivity. This study designed a continuous-flow reaction system combined nano-sized TiO2 photocatalysis with ozone oxidation technology to decompose VOCs from cooking oil fume. After passing through a fiberglass filter to remove oil droplets, the cooking oil fume then coated with nano-sized titanium oxide (UV/TiO2) fiberglass filter purification system, and then injected ozone into the system to decompose residual VOCs. This study further investigated the influences of operating parameters, including TVOCs initial concentration, O3 injection concentration, and reaction temperature on the decomposition efficiency of TVOCs by using the UV/TiO2/O3 technology. When the photocatalytic reaction temperature was 35~50¢J, the TVOC decomposition efficiency slightly increased with reaction temperature, however, when the reaction temperature went up to 55¢J, the TVOC decomposition efficiency increased only slightly, but did not increased linearly. Combination of photocatalysis and ozone oxidation system performance test results showed that ozone could decompose approximately 34% VOCs, and followed by the photocatalytical reaction of residual pollutants, achieving an overall decomposition efficiency of about 75%; while photocatalytic reaction can remove 64% of TVOCs and followed by O3 for the decomposition of residual pollutants, achieving an overall decomposition efficiency up to 94%. It showed that the combined UV/TiO2+O3 system could effectively remove VOCs in the cooking oil fume from the exhaust of restaurants. By using GC/MS to qualitatively analyze the speciation of TVOCs from cooking oil fume before and after UV/TiO2/O3, the results showed that the composition of VOCs had a decreasing trend. The peak area and dilution factor were applied to estimate the decomposition efficiency of different VOCs species. The decomposition efficiencies of pentane, 2-acrolein, acrolein, heptane, pentanal, hexanal, 2-hexenal, heptanal, heptenal and ethylhexenal were 56.21%, 72.88%, 51.33%, 32.23%, 59.04%, 69.22%, 73.53%, 41.37%, 92.57%, and 96.02%. Finally, a Langmuir-Hinshelwood kinetic model was applied to simulate the photocatalytic decomposition efficiency with the initial concentration of cooking oil fume. Model simulation results showed that the reaction rate increased with the initial TVOCs concentration. However, when TVOCs concentration increased gradually, the reaction rate became constant since the activated sites on the photocatalyst¡¦s surface was limited and cannot allow more VOC molecules diffuse to the activated sites for further photocatalytic reaction.

Lipoxygenase (LOX)-derived oxylipins are known to play critical roles in defense against herbivores and pathogens. The objective of this study was to determine the biochemical, molecular and physiological roles of a specific maize lipoxygenase gene, ZmLOX10, with special emphasis on LOX10-derived oxylipins in plant-insect and plant-pathogen interactions. To achieve this goal, independent mutant alleles were generated and genetically advanced to create near-isogenic mutant and wild-type lines suitable for functional analysis. Here we provide genetic evidence that LOX10 is the sole LOX isoform in maize required for the biosynthesis of green leafy volatiles (GLV) in leaves and show that LOX10- mediated GLVs play a significant role in direct and indirect defense responses to insects through their regulation of jasmonic acid and volatile organic compound production. Contrary to the defensive role of LOX10 in plant-insect interactions, tests for susceptibility to fungal pathogens suggest that LOX10-mediated GLVs may contribute to the development of disease symptoms to the economically important maize pathogens, Aspergillus flavus and Colletotrichum graminicola. Specifically, LOX10-derived GLVs may facilitate aflatoxin accumulation in response to A. flavus infection and may play a positive role in anthracnose leaf blight and stalk rot caused by C. graminicola. Collectively, our results suggest that metabolites derived from GLV-regulated pathways have a significant impact on molecular plant-herbivore and plant-pathogen interactions.

The concentrations of seventy-one hydrocarbons (HC) from C2 to C15 were measured simultaneously at two sites in Kaohsiung city in the morning (07-10), the afternoon (13-16), and the evening (18-21) on 14 days in spring 2003. Results show that the most abundant species of Kaohsiung¡¦s air is toluene (43.36-54.49 £gg m-3), followed by i-pentane, 1,2,4-trimethylbenzene, benzene, n-butane, propane and acetylene, in the range 10.36¡V17.11 £gg m-3. The concentrations of 14 halocarbons are in the range 0.25¡V4.57 £gg m-3. Alkanes (around 44.8%) represent the largest proportion of the total HC, followed by aromatics (35.1%), alkenes (15.5%) and halocarbons (5.4%). The afternoon HC concentrations are much lower than those in the morning and at night, due to relatively intense photochemical reaction and favorable dispersion conditions from noon to afternoon. Notable increases in daily HC concentrations are consistent with high temperature, and low HC concentrations on Sunday coincide with low traffic volume. Photochemical activity is investigated, and HC concentrations are found to decline as the NO2/NOx ratio increases. Correlation analyses imply that vehicle exhaust is the dominant source of atmospheric hydrocarbons in Kaohsiung. The profiles of traffic exhausts were also measured for 25 HC species during the morning and afternoon rush hours on four different days in all three traffic tunnels in Kaohsiung City. Results show that VOC concentrations increase with traffic flow rate, and emission profiles in the three tunnels are mostly in the range C2 ¡V C6. Besides the traffic conditions and vehicle type, the pattern of emissions in each tunnel was also influenced by other factors, such as vehicle age, nearby pollution sources, and the spatial or temporal variation of HC in the urban atmosphere. The ozone formation potential (OFP) in each tunnel was assessed based on the maximum incremental reactivities of the organic species, demonstrating that OFP increases with traffic flow rate. Vehicle distribution influences the contributions of organic group to OFP in a tunnel. Meanwhile, when ranked in descending order of contribution to OFP in all tunnels, the organic groups followed the sequence alkenes, aromatics, and alkanes. The possible source categories affecting the atmospheric HC species were further analyzed using factor analysis. Results showed that the major sources of ambient HC at the Nan-Chie and Hsiung-Kong sites are: vehicle exhaust, petrol/diesel exhaust, industrial processes (for example, plastic/rubber process), combustion exhaust, solvent fugitive or business/consume exhaust. Based on the results of factor analysis, source profiles (or fingerprints) were selected and receptor modeling was conducted based on chemical mass balance (CMB). Results of receptor modeling indicated that, at Nan-Chie site, vehicle exhaust (46.33% and 56.36%) represent the largest proportion of total HC, followed by industrial processes (29.63% and 22.37%) in the morning (07-10) and the evening (18-21), respectively; but were industrial process (40.39%) and solvent fugitive exhaust (30.61%) in the afternoon (13-16). Similarly at Hsiung-Kong site, vehicle exhaust (around 46.19% and 49.29%) represent the largest proportion of total HC, followed by industrial processes (23.19% and 26.11%) in the morning and evening, respectively; but were solvent fugitive exhaust (38.85%), vehicle exhaust (28.95%) and industrial process (25.19%) in the afternoon. It is evident that relatively low traffic volumes in the afternoon at both sites reduce the contribution of traffic exhaust to ambient HC.

This research focuses on the performance study of a full-scale biofilter for treating a stream of vent gas with airborne VOCs generated from a chemical plant wastewater treatment facility. The biofilter consists of two parallel 20-ft standard containers in each a space of 5.98 m in length, 2.35 m in width and 0.50 m in height were filled with biofiltering media prepared by blending swine-manure compost and fern chips in a certain proportion. The vent gas contains methane, methanol, ethanol, acetone, dichloromethane, methyl ethyl ketone, ethyl acetate and toluene as major components and has an average flow rate of 1,320 m3/h (22 m3/min) and a temperature of 16-40oC. The purposes of this research were to confirm the VOC removal efficiency and to evaluate the elimination capacity for each VOC by monitoring operating parameters, including gas flow rate, system temperature, influent and effluent VOC concentrations of the biofilter. Experimental results show the system has a volumetric influent gas flow rate 1,153-1,470 m3/h which resulted in an average gas empty bed retention time (EBRT) of 0.64 min through the bed, a moisture of 25-70% and a pH of 2.4-6.9 for the media. Removal efficiencies of methane, methanol, ethanol, acetone, dichloromethane, MEK, ethyl acetate, toluene, NMHC and THC were 23.1, 79.3, 95.2, 82.9, 53.5, 63.7, 83.9, 41.2, 76.2 and 50.5%, respectively. Results also indicate that the VOC removal efficiency for each compound was not directly related to such important operating parameters of the biofilter as influent gas flow rate, media temperature, media pH, and the VOC concentration of the influent gas. However, the volumetric elimination rate (K) was approximately linearly varied with the corresponding loading (L) for the biodegradable VOCs in the influent gas. An average removal efficiency (K/L) of 24.5% was obtained with loadings of L < 70 g/m3h for methane. K/L of 91 and 54% were obtained for methanol with L = 0-7 and 15-22 g/m3h, respectively. Average K/L of 95% was obtained for both ethanol and acetone with L < 40 g/m3h. Removal efficiencies of 48 and 76% were obtained for methanol with L = 0-10 and 18-35 g/m3h, respectively. For MEK, an average removal of 89% was obtained with L = 0.5-4 g/m3h. Removal efficiencies of 84, 37, 48, 76 and 51% were obtained with L < 20, 0-0.2, 0.3-0.8 <60 and <120 g/m3h for ethyl acetate, toluene, NMHC and THC, respectively. This full-scale biofilter is effective in removing ethanol, ethyl acetate, acetone, methanol, and MEK. There is no significant removal efficiency for dichloromethane, toluene and methane. The performance can hopefully be improved by controlling the media in suitable conditions of moisture 50-60% and pH 7-8.

Abstract Biological processes have been proven to be economical and effective for control of VOCs with concentration of <1,000 mg C/m3. This study armed to develop a biofilter packed only with fern chips for the removal of airborne isopropyl alcohol (IPA). A three-stage down-flow biofilter (2.2 m in height and 0.4 m¡Ñ0.4 m in cross-sectional area) was constructed for the performance test. The first stage serviced as a humidifier for the incoming gas and the following two stages, both packed with fern chips with a packing space of 0.30 m ¡Ñ 0.40 m ¡Ñ0.40 m, as trickling bed biofilters for the VOC removal. Air with a nearly constant IPA concentration of 100 mg/Am3 (@ an average temperature of 34 oC) and a flow rate in the range of 100-400 L/min was fed to the reactor in Phase I test. The flow rate gave an empty bed retention time (EBRT) in the range of 12-48 s for the gas flowing through the two bed media. Solutions of urea-N, phosphate-P, and milk powder were supplied daily to the fern chips for the microbial nutrition in Phase I experiment which lasted for 26 days. Following the Phase, Phase II test operated with a constant EBRT of 12 s and without any nutrient supplementation for 30 days. Experimental results show that with an influent gas temperature of 29-40oC (average 34 oC) and relative humidity of 43-93% (average 73%), with a proper moistening of the bed media, the effluent gas could achieved a temperature of 26-35oC (average 29 oC) and a relative humidity of 98%. The proceeding medium experienced a greater moisture variation (12-68%, average 38%) than that (65-82%, average 72%) of the following one. The former and the latter media had pH in the range of 6.11-7.78 (average 6.77) and 6.13-7.36 (average 6.59), respectively. With no additional nutrient supplementation for 30 days, approximately 98% of the influent IPA of 100 mg/m3 could be removed at the EBRT of as short as 12 s which corresponded to a loading of 60 g IPA/m3.h.

Adsorption/desorption behaviors of three volatile organic compounds (VOCs) emitted from the optoelectronics industry by Y-type and ZSM-5 zeolites were studied in this work. Target VOCs include acetone, isopropyl alcohol (IPA), and propylene glycol monomethyl ether acetate (PGMEA). Adsorption/desorption experiments were conducted in a fixed-bed column using various operating conditions to mimic the commercial ones. Also studied include the adsorption kinetics for single-component, two-component, and three-component cases. Experimental results of the single-adsorbate case by both model zeolites have shown that the amount of VOC adsorbed follows the order of PGMEA > IPA > Acetone. This is ascribed to the greatest molecular weight of PGMEA among three VOCs tested. The adsorption capacity of each zeolite for each target VOC was found to increase with its increasing initial concentration. Freundlich isotherm and Langmuir isotherm were found to be suitable for describing the adsorption behaviors for the single-adsorbate case. Results of the desorption experiments also showed that most of the target VOCs could be desorbed at 180¢J in 100 minutes. The adsorption capacities of the regenerated model zeolites were found to be decreasing as the regeneration times increased. As compared with the fresh ones, the regenerated zeolites had reduced specific surface areas, but increased pore sizes. In addition, the Yoon and Nelson equation was employed to study the kinetic behaviors of adsorbing the target VOCs by the model zeolites. A good agreement of the experimental results and predictions by the Yoon & Nelson model was obtained for the single-adsorbate case. However, the Yoon and Nelson model was found to be incompetent to simulate and predict all the multi-adsorbate cases including two-component adsorption and three-component adsorption in this work. Again, it is speculated that the displacement of lower-molecular-weight adsorbates (i.e., acetone and IPA) by PGMEA (an adsorbate of a much greater molecular weight) would be responsible for this finding. For the two-adsorbate case, nevertheless, the Yoon and Nelson equation was found to be capable of describing the adsorption behavior under the circumstance of C/C0 < 1.

This study armed to develop a biofilter packed only with fern chips for the removal of air-borne propylene glycol monomethyl ether acetate (PGMEA). The fern chip biofilters could avoid the shortcomings of traditional media, such as compaction, drying, and breakdown, which lead to the performance failure of the biofilters. In the present study, a three stage down-flow biofilter (2.18 m in height and 0.4 m¡Ñ0.4 m in cross-sectional area) was constructed for the performance test. The first stage serviced as a humidifier for the incoming gas and the following two stages, both packed with fern chips of 0.30 m ¡Ñ 0.40 m ¡Ñ0.40 m, as trickling bed biofilters for the VOC removal. The experiment was divided into four phases. Operation conditions of an empty bed retention time (EBRT) of 1.60min and influent PGMEA concentrations of 9.33-329 (average 78.4) mg/m3 were used in the Phase I experiment which lasted for 99 days. An average PGMEA removal of only 68% was obtained in this phase. For improving the PGMEA removal in the following phases, a fixed dosage of milk powder of 1.0 g/(m3 media. day) added as aqueous milk suspension was added to the media for nutrition of the biofilms on the fern chip surfaces. After an additional operation time of 20 days (the 127th day from the startup time), a stable PGMEA removal of 91% was achieved. Following Phase II, PGMEA removals of 93 and 94% were obtained with EBRTs of 0.40 and 0.27 min, respectively, in Phases III and IV experiments. The results indicate that EBRT was not a key influencing factor to the PGMEA removal as long as the media had a high ability for the VOC degradation. Experimental data obtained from Phases II-IV reveal that with volumetric loadings (L) of less than 250 g PGMEA/(m3.h) to the up-streaming half of the whole media, 90% of the influent PGMEA could be removed in this half media. An additional 80% of the influent PGMEA to the following half media could be removed with L < 100 g PGMEA/(m3.h) to the half media. The PGMEA elimination capacities were proportional to the volumetric loadings of less than 250 g PGMEA/(m3.h). From the results, it could be proposed that for achieving over 93% of the PGMEA removal, appropriate operation conditions are media moisture content = 52-65%, media pH = 7.2-7.4, influent PGMEA concentration = 100-400 mg/Am3, EBRT = 0.27-0.40 min, and L to the whole media = 45-180 g PGMEA/(m3.h).

This study investigates characteristics of odorous materials and their odor intensities emitted from various commercial and industrial sources in the Kaohsiung City. An overview of odor complaints from the city people is presented and discussed. Results indicate that, due to the increasing people concerns about the odor emission problems, more frequent checks done by the City EPA officers, governmental assistances to the pollution makers on the pollution control technologies, and the enforcement of more stringent environmental protection regulations, odor-complaint cases in this city are decreasing in recent years. However, people are giving more attention to odors from food-cooking emissions and the associated complaint cases are increasing. Emissions from restaurants and plants become the two major odor sources in this city. For the plant emissions, odorous chemicals emitted from the Kaohsiung Refinery, located in northern Zouying District, were detected to be benzene, toluene, xylenes, and styrene. The Chianjhen storage and pumping station, located by the Kaohsiung Harbor, emits some 40 different chemicals. The majors among them are methanol, ammonia, ethylene, n-pentane, chlorodifluoromethane, methyl tert-butyl ether (MTBE), propylene, cyclohexane, styrene, acetone, 1,2-dichloroethane, propylene oxide and vinyl chloride. Prompt leaks from the storage tanks and during the loading and unloading operations account for the emissions. Plants located in the Chianjhen Export Processing Zone emit chemicals, mainly methyl methacrylate, toluene, propylene glycol monomethyl ether acetate (PGMEA), ammonia, ethyl acetate and ethanol, which cause only a few complaint cases. The emitted chemicals are among the ones used by the plants as feed stokes or solvents. Restaurant located in Chianjhen and Hsiogang Districts emit large amount of food-cooking odorants, however, the percentage of odorous complaining for the emissions is relatively high in the Zouying District as compared to the other administrative districts investigated in this study. Major components of the food-cooking emissions include hydrogen sulfide, dimethyl sulfide (DMS), dimethyl disulfide (DMDS), ammonia, and methylamine. Relative percentages among these chemicals depend on the cooking materials and styles. Results also indicate that industries or businesses, such as petrochemical, surface coating, paint manufacturing, fuel station, storage vessels, semiconductor manufacturing, adhesive tape manufacturing and cloth dry-cleaning, are major odor and chemical emission sources which need to be continuously implemented for getting more emission reductions in the near future.