ABSTRACT Being a densely populated and heavily industrialized harbor, the emissions of air pollutants in the Kaohsiung area are very huge. There is substantial amount of VOCs (volatile organic compounds) present in the ambient air. Furthermore, relative high temperature and strong sunlight tend to transform these VOCs to oznone, causing high ozone episodes. This study aimed to determine the VOCs source profiles (or fingerprints) from 20 stationary sources, 10 from each of Kaohsiung City and Kaohsiung County. These include flue gas emission from incineration plants, sewage treatment plants, petroleum plants, and others. The samples was collected using a stainless-steel thermal desorption tube, then analyzed a Hewlett-Packard 58900-II gas chromatograph, fitted with a flame ionization detector and desk-top personel computer. The OFP (ozone formation potential) of VOCs from individual sources were evaluated based on MIR (maximum incremental reactivities). The results show that the speciations of VOCs depend on the raw material and air pollution control equipments used in the processes. The major VOCs in the petro-chemical industries are benzene, toluene, xylene, and 1,3,5-trimethylbenzene. The major VOCs in the PVC processes and surface-painting industries are 2-methylbutane, 2-methylpentane, and ethylbenzene. The major VOCs in the sewage treatment plants are ethylene, hexane, benzene, toluene, and m-xylene. The highest average reaction of the samples is 27.94 g-O3/g-VOCs from intermediary process, the next are from lubrication oil distillation tower, TPE process, ABS process, and maleic anhydride process, ranging from 3 ~ 5 g-O3/g-VOCs. Thus, the reactivity of aromatic-related process is highest, the next are aldehydes - and ketones -related processes. Keywords: Volatile Organic Compounds, Fingerprints, Ozone Formation Potential

Kaohsiung is a densely populated harbor city, in which the density of motor vehicles is also high. Since the temperature and sunlight is also relatively high in Southern Taiwan, tending to transform ambient volatile organic compounds to ozone thus causes high ozone events. This study measured the concentrations of 63 hydrocarbon (HC) species from C2 to C15 simultaneously at the Nan-Chie and Hsiung-Kong sites in Kaohsiung city during the morning (07-10), the afternoon (13-16), and the evening (18-21) periods on three successive days in winter 2004. Results show that the most abundant species of Kaohsiung¡¦s air is toluene (43.01-60.95 £gg/m3), followed by i-pentane, 1,2,4-trimethylbenzene, benzene, n-butane, propane, and acetylene, in the range 9.55-16.93 £gg/m3, while the concentrations of halocarbons is 0.17-4.12 £gg/m3. Alkanes (44.7-45.9%) represent the largest proportion of the total HC, followed by aromatics (35.4-36.8%), alkenes (10.5-10.9%) and halocarbons (3.6-3.9 %). The OFP (ozone formation potential) of HC species were evaluated based on the MIR (maximum incremental reactivity). Results show that aromatics (45.9-54.3%) represent the largest proportion of the OFP, followed by alkenes (17.7-37.5%), and alkanes (16.5-23.6%). The results from the factor analyses show the major sources of ambient HC in Kaohsiung city are the vehicle exhausts, industrial processes, solvent evaporations, combustion exhausts, and petrochemical processes.

In this research, used dimethyl ether as second fuel blended with diesel (mixed quantity with 10 L/min to 60 L/min, interval 10L/min), which test behavior of diesel engine and carbonyls emission investigated. The engine operated at steady-state condition of 1600 rpm, 145 Nm torque , eight kinds of carbonyls were sampling and analysis, and discuss the performance of the ozone formation potential (OFP). The results of regulated pollutant emissions, CO, THC and PM emission could increasing with the addition of DME, NOX emissions, along with the mixed rate of per minute from 10 L, 20 L, 30 L, 40 L, 50 L and 60 L of its reduction rate was 6.8%¡B8.3%¡B10.0%¡B10.6%¡B13.1% and 15.4%, shows that the DME can reduce NOX emissions. Add a various amount of dimethyl ether , which carbonyl compounds emission from the gas flow 0 L(with neat diesel), 10 L, 20 L, 30 L, 40 L, 50 L and 60 L concentrations were 2507.44 g/m3, 2665.27 g/m3, 2726.67 g/m3, 2958.07 g/m3, 4645.87 g/m3, 5470.20 g/m3 and 7279.91 g/m3; the emission factor of 143.58 mg/bhp-hr, 152.65 mg/bhp-hr, 156.62 mg/bhp-hr, 168.69 mg/bhp-hr, 266.22 mg/bhp-hr, 312.38 mg/bhp-hr and 416.36 mg/bhp-hr, shows the addition of DME will rising the carbonyl compound emissions of diesel engine. Gas of dimethyl ether (10,20,30,40,50 and 60 L/min) into the neat diesel fuel (0 L/min) as a mixture fuel additives, the effect of ozone formation potential as increase in the total ozone formation potential, 21945.93 g-O3/m3, 23698.40 g-O3/m3, 24427.46 g-O3/m3, 26672.98 g-O3/m3, 42683.69 g-O3/m3, 50519.26 g-O3/m3 and 67710.60 g-O3/m3 respectively, and ozone manufacturability will 0 L/min of 8.75 increased to 60 L/min of 9.30.

This research conducted exhaust tests in an HDDE (heavy-duty diesel engine) using pure diesel fuel mixed with 10 to 30% isobutanol under the condition of U.S. Transient Cycle. Characteristics of 18 carbonyls emissions were investigated and compared with those using pure diesel. Results showed that the brake power (BP) and brake thermal efficiency (BTE) were decreased with increasing isobutanol mixtures (10 to 30%). Brake specific fuel consumption (BSFC) was increased for isubutanol ¡Ø 10%, but was decreased for isubutanol above 10%. The regulated emissions of CO, PM and NOx were decreased, but CO2 and THC were increased, due to variations of cetane number and heating value. Total carbonyls emission concentrations with pure diesel fuel were 893.25 £gg/m3, with emission factors being 52.57 mg/bhp-hr or 218.44 mg/L-fuel. When 10 to 30% isobutanol mixture was added, total carbonyls concentrations ranged from 1108.21 to 2622.27 £gg/m3, with emission factors being 268.83 to 610.94 mg/L-fuel, or 68.93 to 175.25 mg/bhp-hr. The ozone formation potential of diesel engine with pure diesel fuel was 7132.72 g-O3/m3.When 10 to 30% isobutanol mixture was used, total ozone formation potential ranged from 8764.39 to 20168.73 g-O3/m3. Total carbonyls emissions were increased with increasing isobutanol contents. In summary, addition 10% isobutanol was an optimal blend, since both fuel saving and reductions of pollutant emissions can be achieved.

Hsuehshan tunnel which included two bore and three ventilation shaft systems is the longest (12.9 km) freeway tunnel in Taiwan. 56 species volatile organic compounds (VOCs) were sampled in two different locations each bore and three emitted shafts to determine the emission factors (EFs). Each sampling day has three sampling period: morning (8:00-10:00), Noon (12:00-14:00) and afternoon 16:00-18:00). C2 species were analyzed by GC/FID and C3 − C12 species were analyzed by GC/MS. The composition in southern bore was expressed by alkanes (36.69% − 39.20%), aromatics (34.14% − 36.33%), alkenes (20.27% − 21.95%), Alkynes (3.35% − 4.11%) and Naphthenes (1.06% − 1.35%). Northern bore had the similar profile. Ethylene (4.93 ¡Ó 2.21 mg/veh-km), Isopropane (4.85 ¡Ó 2.75 mg/veh-km), toluene (4.55 ¡Ó 1.31 mg/veh-km), m,p-xylene (2.98 ¡Ó 0.90 mg/veh-km) and propylene (2.70 ¡Ó 0.88 mg/veh-km) are the top five abundant VOCs in southern bore ; Isopropane (6.78 ¡Ó 3.33 mg/veh-km), ethylene (5.44 ¡Ó 2.63 mg/veh-km), toluene (5.32 ¡Ó 2.39 mg/veh-km), propylene (3.55 ¡Ó 1.67 mg/veh-km) and m,p-xylene (3.36 ¡Ó 1.45 mg/veh-km) are the top five abundant VOCs in northern bore. The EFs were smaller than other freeway tunnel investigated. Shaft emitted the partial mass of VOCs result in concentration gradient dropped off. The total VOCs EF of shafts during holidays was in the range of 72.24 mg/s − 180.60 mg/s higher than on weekdays in the range of 53.40 mg/s − 82.74 mg/s. The EF of shafts had effected by air-extracting apparatus, so standard deviations (S.D.) varied widely. Combining the EF of shaft with EF of tunnel we obtained the overall vehicle EF which was close to other freeway tunnel results. The proportion of Ozone formation potential (OFP) in both bore were alkenes (47.5% − 48.5%), aromatics (40.2% − 42.3%) and alkanes (9.8% − 10.1%). Note that sum of alkenes and aromatics exceeded 90%.

Metro Kaohsiung with high percentage (6-10 %) of poor air quality (PSI>100) has been announced officially by Taiwan Environmental Protection Administration (TEPA) as the worst air quality region among seven Air Quality Zones (AQZ) in Taiwan. Ozone is one of two major air pollutants that are responsible for the poor air quality. In this study, the vertical concentration profiles of ozone and its precursors (NOX and VOCs) at eight sites were measured by tethered balloons with air pumps and tedlar sampling bags. This method was used to investigate the vertical profile and the tempospatial distribution of ozone and its precursors in offshore/inland regions. This study further investigated ozone formation mechanism and air mass trajectory via simultaneous air quality sampling around the coastal region of metro Kaohsiung. This study sampled the vertical concentration profiles of ozone and its precursors at both inland and offshore sites during eight intensive sampling periods on August 16-17 and November 2-3, 2006, January 24-25, March 6-7 and May 2-3, 2007, October 30-31, 2008, and March 11-12 and July 15-16, 2009. Eight sampling periods were divided into the sea-land breeze period, the northeast monsoon period, and the mixing wind field period. During the sea-land breeze period, the wind direction changed 90˚ and more between daytime and nighttime, and the wind speeds of the sea breezes varied significantly than those of the land breezes. During the northeast monsoon period, prevailing wind blew from the north (300~60˚) with the average wind speeds of 1~4 m/s. During the mixing wind field period, the wind direction varied significantly from 270˚ to 90˚ with the average wind speeds of 1~3 m/s. Results obtained from the vertical profiles showed that O3 concentration appeared stratification phenomenon at 40 out of 64 sampling sites, in which its precursors (NOX or VOCs) demonstrated stratification phenomenon at 30 sampling sites, accounting for 75 % of total O3 stratification. It suggested that ozone and its precursors had strong correlation with each other. The linear slope of the titration effect showed that the intensity of titration effect at night during the northeast monsoon period was larger and had higher correlation (R> 0.7), and followed by the mixing wind field period and the sea-land breeze period. This phenomenon correlated closely with meteorological conditions, the concentrations of O3 precursors, and solar radiation intensity. Therefore, O3 concentration at night during the northeast monsoon period was lower than those of the sea-land breeze period. Results obtained from VOCs measurement indicated that the major species of VOCs was acetone which accounted for 16.25~64.05 % of total TVOCs-C2 in the offshore region. High concentration of TVOCs-C2 was affected by the usage of organic solvents. While, the major species of VOCs in the inland region was toluene which accounted for 6.41~43.77 % of total TVOCs-C2. Furthermore, results obtained from backward trajectory showed that air pollutants emited from land sources could transport to the offshore region, resulting in high concentration of oversea NOX and VOCs. Major species of VOCs for high O3 formation potential were aromatics and vinyls at the height of 0~500 m around the coastal region of metro Kaohsiung. The control of O3 precursors concentration showed that the ratio of [TVOCs-C2]/[NOX] in the offshore region was higher, indicating that O3 formation was NOX-limited. Therefore, NOX must be controlled for reducing O3 formation. However, the ratio of [TVOCs-C2]/[NOX] in the inland region was lower, some cases even below 4, showing that O3 formation was VOCs-limited. Thus, VOCs must be controlled for reducing O3 formation.

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.

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.