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1.
Article in English | MEDLINE | ID: mdl-35886499

ABSTRACT

Lung samplers (periodic sampling) have generally been used to develop CH4 emission factors in waste incineration facilities. Since this method must be calculated using only the value at a specific point in time, it may not reflect the emission characteristics depending on the circumstances of the facility. In order to supplement this method, a method of continuously collecting samples for a long period of time or continuously measuring may be used. In this study, the CH4 emission factor development and titration methodology were reviewed using both the existing methods and the newly proposed continuous sampling and continuous measurement methods. As a result of the analysis, the average emission factor by periodic sampling was 0.201 gCH4/ton-waste, the average emission factor by continuous capture was 0.199 gCH4/ton-waste, and the average emission factor by continuous measurement was 0.176 gCH4/ton-waste. There was a difference of 0.025 gCH4/ton-waste in the emission factor values by periodic sampling and continuous measurement, and the emission factor values for periodic sampling and continuous sampling were similar. There was no statistically significant difference, confirming that all three methods could be used. However, the existing method, periodic sampling, cannot reflect the characteristics of the night, and, in the case of continuous measurement, expensive equipment and maintenance are difficult. Therefore, it is judged that the method using continuous sampling is a good method that can combine the two advantages.


Subject(s)
Incineration , Solid Waste , Solid Waste/analysis
2.
Article in English | MEDLINE | ID: mdl-35682287

ABSTRACT

Fertilizers are made from manure, but they are also produced through chemical processes. Fertilizer is an ammonia emission source; it releases ammonia when used. Ammonia is also emitted during the production process. Although many studies related to fertilizer application have been conducted, there are few research cases related to the production process and related emissions are not calculated. In this study, the ammonia emissions from NPK (nitrogen phosphorus Potassium oxide) fertilizer production facilities were checked through actual measurement and related characteristics were analyzed. In addition, emission factors were developed, and the necessity of developing emission factors was also confirmed. As a result of the development of the emission factor, it was found to be 0.001 kgNH3/ton, which is like the range of emission factors in related fields. The NPK ammonia emission factor of this study was found to be higher than the minimum emission factor currently applied in South Korea, and it was judged to be a level that can be used as an emission factor.


Subject(s)
Ammonia , Fertilizers , Agriculture , Ammonia/analysis , Manure , Nitric Oxide , Nitrogen , Nitrous Oxide/analysis , Soil
3.
Article in English | MEDLINE | ID: mdl-35627484

ABSTRACT

In this study, the emission factor and concentration of ammonia from industrial waste incineration facilities were analyzed through actual measurements. The ammonia emission factor was calculated and the difference in ammonia emission factor for each type of incineration was confirmed through the Mann−Whitney U test. As a result of analyzing 279 samples, the NH3 emission factor of the SNCR facility of stoker types was 0.012 kgNH3/ton, and the NH3 emission factor of the SNCR facility of the rotary kiln methods was 0.014 kgNH3/ton. Additionally, the NH3 emission factor of this study was higher than the NH3 emission factor (0.003 kgNH3/ton) suggested by Kang's study (0.009 kgNH3/ton) and EMEP/EEA (2006). There is a need to develop an NH3 emission factor that takes into account the characteristics of Korea, since it is largely different from the NH3 emission factor of EMEP/EEA. As a result of statistical analysis of the stoker type and the rotary kiln method, the null hypothesis that there is no difference between each type was adopted (p-value > 0.05), indicating that there was no statistical difference in the ammonia emission factors of the stoker type and the rotary kiln type.


Subject(s)
Incineration , Industrial Waste , Ammonia , Incineration/methods , Republic of Korea
4.
Article in English | MEDLINE | ID: mdl-34770065

ABSTRACT

Ammonia is a representative PM-2.5 secondary product, and the need for management is emerging as health and living damage caused by fine particulate matter worsens. The main source of ammonia is the agricultural sector, and in Korea, 79% of the total ammonia emissions are emitted from the agricultural sector. Among them, there is high uncertainty about how to calculate emissions from ammonia discharged from fertilizer use, and inventory in the U.S. and Europe is borrowed, so inventory needs to be improved according to the situation in Korea. In this study, the ammonia inventory in the agricultural sector in Korea and abroad was examined, and additional activity data that can be used were reviewed. In addition, in order to improve the emission calculation method, the emission was calculated in three ways by different factors. As a result, it was confirmed that the amount of discharge varies depending on the type of soil use or whether cultivated crops are considered, and the possibility of excessive fertilizer top-dress by farmers was confirmed. In order to calculate the emission at a more detailed level based on this study, basic data such as fertilizer input method and regional distribution of crops should be systematically collected, and related follow-up studies should be conducted.


Subject(s)
Air Pollutants , Fertilizers , Agriculture , Air Pollutants/analysis , Ammonia/analysis , Fertilizers/analysis , Nitrogen/analysis , Soil
5.
Article in English | MEDLINE | ID: mdl-33923606

ABSTRACT

In order to cope with recent climate change, Korea is reducing the use of heavy oil in petroleum-fired power plants and mixing bio-oils. Accordingly, this must be taken into account when calculating the emissions of air pollutants. However, in the case of Korea, when calculating NH3 emissions, the United States Environmental Protection Agency (EPA) emission factor is applied as it is to calculate emissions, and for petroleum power plants, the heavy oil emission factor proposed by EPA is used as it is to calculate emissions. In petroleum power plants, bio-oil is not mixed in a certain amount and used at a different ratio depending on the situation of the power plant. Therefore, in this study, the NH3 emission factor according to the mixing ratio of bio-heavy oil is calculated and the mixing ratio is calculated. As a result of the analysis, the emission factor according to bio-oil and the mixed ratio was found to be in the range of 0.010~0.033 kg NH3/kL, and it was lower than the heavy oil emission factor 0.096 kg NH3/kL of EPA currently used in Korea. This is because the amount of NH3 through the slip is also small since the use of NH3 for reduction is also low because the NOx emission from the use of bio-oil is low. Considering all of these points, we have statistically analyzed whether emission factors should be developed and applied. As a result of the confirmation, the difference according to the mixed consumption rate was not large.


Subject(s)
Air Pollutants , Air Pollution , Air Pollutants/analysis , Air Pollution/analysis , Ammonia , Environmental Monitoring , Plant Oils , Polyphenols , Power Plants , Republic of Korea , United States
6.
Article in English | MEDLINE | ID: mdl-33806374

ABSTRACT

In the case of sewage sludge, as direct landfilling was recently prohibited, it is treated through incineration. Among the air pollutants discharged through the incineration of sewage sludge, NOx and SOx are considered secondary substances of PM2.5 and are being managed accordingly. However, NH3, another of the secondary substances of PM2.5, is not well managed, and the amount of NH3 discharged from sewage sludge incineration facilities has not been calculated. Therefore, in this study, we sought to determine whether NH3 is discharged in the exhaust gas of a sewage sludge incineration facility, and, when discharged, the NH3 emission factor was calculated, and the necessity of the development of the emission factor was reviewed. As a result of the study, it was confirmed that the amount of NH3 discharged from the sewage sludge incineration facility was 0.04 to 4.47 ppm, and the emission factor was calculated as 0.002 kg NH3/ton. The NH3 emission factor was compared with the NH3 emission factor of municipal solid waste proposed by EMEP/EEA (European Monitoring and Evaluation Programme/European Environment Agency) because the NH3 emission factor of the sewage sludge incineration facility had not been previously determined. As a result of the comparison, the NH3 emission factor of EMEP/EEA was similar to that of municipal solid waste, confirming the necessity of developing the NH3 emission factor of the sewage sludge incineration facility. In addition, the evaluation of the uncertainty of the additionally calculated NH3 emission factor was conducted quantitatively and the uncertainty range was presented for reference. In the future, it is necessary to improve the reliability of the NH3 emission factor of sewage sludge incineration facilities by performing additional analysis with statistical representation. In addition, the development of NH3 emission factors for industrial waste incineration facilities should be undertaken.


Subject(s)
Incineration , Sewage , Ammonia , Reproducibility of Results , Solid Waste
7.
Article in English | MEDLINE | ID: mdl-32466436

ABSTRACT

This study developed the NH3 emission factor for Liquefied Natural Gas (LNG) power facilities in Korea by analyzing the emission characteristics from two LNG power plants using methods such as uncertainty analysis. Also, comparing the differences in NH3 emission levels between the developed emission factors, which reflect the characteristics in Korea, and the U.S. Environmental Protection Agency (EPA) values currently applied in Korea. The estimation showed that the NH3 emission factor for the LNG power plants was 0.0054 ton NH3/106Nm3, which is approximately nine times less than the EPA NH3 emission factor of 0.051 ton NH3/106Nm3 for LNG fuels of the industrial energy combustion sector currently applied in national statistics in Korea. The Selective Catalytic Reduction (SCR) emission factor for LNG power plants was 0.0010 ton NH3/106Nm3, which is considerably lower than the EPA NH3 emission factor of 0.146 ton NH3/106Nm3 currently applied in national statistics in Korea for the LNG fuels of the industrial process sector. This indicated the need for developing an emission factor that incorporates the unique characteristics in Korea. The uncertainty range of the LNG stack NH3 emission factor developed in this study was ±10.91% at a 95% confidence level, while that of the SCR NH3 emission factor was -10% to +20% at a 95% confidence level, indicating a slightly higher uncertainty range than the LNG stack. At present, quantitative analysis of air pollutants is difficult because numerical values of the uncertainty are not available. However, quantitative analysis might be possible using the methods applied in this study to estimate uncertainty.


Subject(s)
Air Pollutants , Natural Gas , Air Pollutants/analysis , Ammonia , Power Plants , Republic of Korea , Uncertainty
8.
Environ Pollut ; 241: 194-199, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29807279

ABSTRACT

Recently, a novel method for carbon capture and storage has been proposed, which converts gaseous CO2 into aqueous bicarbonate ions (HCO3-), allowing it to be deposited into the ocean. This alkalinization method could be used to dispose large amounts of CO2 without acidifying seawater pH, but there is no information on the potential adverse effects of consequently elevated HCO3- concentrations on marine organisms. In this study, we evaluated the ecotoxicological effects of elevated concentrations of dissolved inorganic carbon (DIC) (max 193 mM) on 10 marine organisms. We found species-specific ecotoxicological effects of elevated DIC on marine organisms, with EC50-DIC (causing 50% inhibition) of 11-85 mM. The tentative criteria for protecting 80% of individuals of marine organisms are suggested to be pH 7.8 and 11 mM DIC, based on acidification data previously documented and alkalinization data newly obtained from this study. Overall, the results of this study are useful for providing baseline information on ecotoxicological effects of elevated DIC on marine organisms. More complementary studies are needed on the alkalinization method to determine DIC effects on seawater chemistry and marine organisms.


Subject(s)
Aquatic Organisms/physiology , Bicarbonates/toxicity , Seawater/chemistry , Water Pollutants, Chemical/toxicity , Acids , Carbon/analysis , Carbon Dioxide/chemistry , Ecotoxicology , Hydrogen-Ion Concentration
9.
Waste Manag ; 71: 176-180, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29030121

ABSTRACT

This study estimates the optimum sampling cycle using a statistical method for biomass fraction. More than ten samples were collected from each of the three municipal solid waste (MSW) facilities between June 2013 and March 2015 and the biomass fraction was analyzed. The analysis data were grouped into monthly, quarterly, semi-annual, and annual intervals and the optimum sampling cycle for the detection of the biomass fraction was estimated. Biomass fraction data did not show a normal distribution. Therefore, the non-parametric Kruskal-Wallis test was applied to compare the average values for each sample group. The Kruskal-Wallis test results showed that the average monthly, quarterly, semi-annual, and annual values for all three MSW incineration facilities were equal. Therefore, the biomass fraction at the MSW incineration facilities should be calculated on a yearly cycle which is the longest period of the temporal cycles tested.


Subject(s)
Incineration , Solid Waste , Biomass , Republic of Korea
10.
J Air Waste Manag Assoc ; 67(8): 923-932, 2017 08.
Article in English | MEDLINE | ID: mdl-28388332

ABSTRACT

Atmospheric concentration of sulfur dioxide (SO2) was intermittently measured at an air quality monitoring (AQM) station in the Yong-san district of Seoul, Korea, between 1987 and 2013. The SO2 level was compared with other important pollutants concurrently measured, including methane (CH4), carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO2), ozone (O3), and particulate matter (PM10). If split into three different periods (period 1, 1987-1988, period 2, 1999-2000, and period 3, 2004-2013), the respective mean [SO2] values (6.57 ± 4.29, 6.30 ± 2.44, and 5.29 ± 0.63 ppb) showed a slight reduction across the entire study period. The concentrations of SO2 are found to be strongly correlated with other pollutants such as CO (r = 0.614, p = 0.02), which tracked reductions in reported emissions due to tighter emissions standards enacted by the South Korean government. There was also a clear seasonal trend in the SO2 level, especially in periods 2 and 3, reflecting the combined effects of domestic heating by coal briquettes and meteorological conditions. Although only a 16% concentration reduction was achieved during the 27-year study duration, this is significant if one considers rapid urbanization, an 83.2% increase in population, and rapid industrialization that took place during that period. IMPLICATIONS: Since 1970, a network of air quality monitoring (AQM) stations has been operated by the Korean Ministry of Environment (KMOE) for routine nationwide monitoring of air pollutant concentrations in urban/suburban areas. To date, the information obtained from these stations has provided a platform for analyzing long-term trends of major pollutant species. In this study, we examined the long-term trends of SO2 levels and relevant environmental parameters monitored continuously in the Yong-san district of Seoul between 1987 and 2013. The data were analyzed over various time scales (i.e., monthly, seasonal, and annual intervals). The results obtained from this study will allow us to assess the effectiveness of abatement strategy and to predict future concentrations trends in association with future abatement strategies and technologies.


Subject(s)
Air Pollutants/analysis , Sulfur Dioxide/analysis , Air Pollution/analysis , Carbon Monoxide/analysis , Environmental Monitoring , Methane/analysis , Nitric Oxide/analysis , Nitrogen Dioxide/analysis , Ozone/analysis , Particulate Matter/analysis , Seoul
11.
J Air Waste Manag Assoc ; 66(10): 978-87, 2016 10.
Article in English | MEDLINE | ID: mdl-27580473

ABSTRACT

UNLABELLED: In this study, in order to understand accurate calculation of greenhouse gas emissions of urban solid waste incineration facilities, which are major waste incineration facilities, and problems likely to occur at this time, emissions were calculated by classifying calculation methods into 3 types. For the comparison of calculation methods, the waste characteristics ratio, dry substance content by waste characteristics, carbon content in dry substance, and (12)C content were analyzed; and in particular, CO2 concentration in incineration gases and (12)C content were analyzed together. In this study, 3 types of calculation methods were made through the assay value, and by using each calculation method, emissions of urban solid waste incineration facilities were calculated then compared. As a result of comparison, with Calculation Method A, which used the default value as presented in the IPCC guidelines, greenhouse gas emissions were calculated for the urban solid waste incineration facilities A and B at 244.43 ton CO2/day and 322.09 ton CO2/day, respectively. Hence, it showed a lot of difference from Calculation Methods B and C, which used the assay value of this study. It is determined that this was because the default value as presented in IPCC, as the world average value, could not reflect the characteristics of urban solid waste incineration facilities. Calculation Method B indicated 163.31 ton CO2/day and 230.34 ton CO2/day respectively for the urban solid waste incineration facilities A and B; also, Calculation Method C indicated 151.79 ton CO2/day and 218.99 ton CO2/day, respectively. IMPLICATIONS: This study intends to compare greenhouse gas emissions calculated using (12)C content default value provided by the IPCC (Intergovernmental Panel on Climate Change) with greenhouse gas emissions calculated using (12)C content and waste assay value that can reflect the characteristics of the target urban solid waste incineration facilities. Also, the concentration and (12)C content were calculated by directly collecting incineration gases of the target urban solid waste incineration facilities, and greenhouse gas emissions of the target urban solid waste incineration facilities through this survey were compared with greenhouse gas emissions, which used the previously calculated assay value of solid waste.


Subject(s)
Air Pollutants/analysis , Carbon/analysis , Environmental Monitoring/methods , Incineration , Solid Waste/analysis , Gases/analysis , Greenhouse Effect
12.
J Air Waste Manag Assoc ; 66(10): 971-7, 2016 10.
Article in English | MEDLINE | ID: mdl-27191178

ABSTRACT

UNLABELLED: In Korea, the amount of greenhouse gases released due to waste materials was 14,800,000 t CO2eq in 2012, which increased from 5,000,000 t CO2eq in 2010. This included the amount released due to incineration, which has gradually increased since 2010. Incineration was found to be the biggest contributor to greenhouse gases, with 7,400,000 t CO2eq released in 2012. Therefore, with regards to the trading of greenhouse gases emissions initiated in 2015 and the writing of the national inventory report, it is important to increase the reliability of the measurements related to the incineration of waste materials. This research explored methods for estimating the biomass fraction at Korean MSW incinerator facilities and compared the biomass fractions obtained with the different biomass fraction estimation methods. The biomass fraction was estimated by the method using default values of fossil carbon fraction suggested by IPCC, the method using the solid waste composition, and the method using incinerator flue gas. The highest biomass fractions in Korean municipal solid waste incinerator facilities were estimated by the IPCC Default method, followed by the MSW analysis method and the Flue gas analysis method. Therefore, the difference in the biomass fraction estimate was the greatest between the IPCC Default and the Flue gas analysis methods. The difference between the MSW analysis and the flue gas analysis methods was smaller than the difference with IPCC Default method. This suggested that the use of the IPCC default method cannot reflect the characteristics of Korean waste incinerator facilities and Korean MSW. IMPLICATIONS: Incineration is one of most effective methods for disposal of municipal solid waste (MSW). This paper investigates the applicability of using biomass content to estimate the amount of CO2 released, and compares the biomass contents determined by different methods in order to establish a method for estimating biomass in the MSW incinerator facilities of Korea. After analyzing the biomass contents of the collected solid waste samples and the flue gas samples, the results were compared with the Intergovernmental Panel on Climate Change (IPCC) method, and it seems that to calculate the biomass fraction it is better to use the flue gas analysis method than the IPCC method. It is valuable to design and operate a real new incineration power plant, especially for the estimation of greenhouse gas emissions.


Subject(s)
Air Pollutants/analysis , Biomass , Environmental Monitoring/methods , Incineration , Solid Waste/analysis , Gases/analysis , Republic of Korea
13.
J Air Waste Manag Assoc ; 65(10): 1256-60, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26252193

ABSTRACT

UNLABELLED: Environmental problems and climate change arising from waste incineration are taken quite seriously in the world. In Korea, the waste disposal methods are largely classified into landfill, incineration, recycling, etc. and the amount of incinerated waste has risen by 24.5% from 2002. In the analysis of CO2emissions estimations of waste incinerators fossil carbon content are main factor by the IPCC. FCF differs depending on the characteristics of waste in each country, and a wide range of default values are proposed by the IPCC. This study conducted research on the existing classifications of the IPCC and Korean waste classification systems based on FCF for accurate greenhouse gas emissions estimation of waste incineration. The characteristics possible for sorting were classified according to FCF and form. The characteristics sorted according to fossil carbon fraction were paper, textiles, rubber, and leather. Paper was classified into pure paper and processed paper; textiles were classified into cotton and synthetic fibers; and rubber and leather were classified into artificial and natural. The analysis of FCF was implemented by collecting representative samples from each classification group, by applying the 14C method, and using AMS equipment. And the analysis values were compared with the default values proposed by the IPCC. In this study of garden and park waste and plastics, the differences were within the range of the IPCC default values or the differences were negligible. However, coated paper, synthetic textiles, natural rubber, synthetic rubber, artificial leather, and other wastes showed differences of over 10% in FCF content. IPCC is comprised of largely 9 types of qualitative classifications, in emissions estimation a great difference can occur from the combined characteristics according with the existing IPCC classification system by using the minutely classified waste characteristics as in this study. IMPLICATIONS: Fossil carbon fraction (FCF) differs depending on the characteristics of waste in each country; and a wide range of default values are proposed by the IPCC. This study conducted research on the existing classifications of the IPCC and Korean waste classification systems based on FCF for accurate greenhouse gas emissions estimation of waste incineration.


Subject(s)
Carbon/analysis , Environmental Monitoring/methods , Fossil Fuels/analysis , Incineration , Solid Waste/analysis , Fossil Fuels/classification , Fossils , Republic of Korea , Solid Waste/classification , Waste Management
14.
Sci Total Environ ; 518-519: 595-604, 2015 Jun 15.
Article in English | MEDLINE | ID: mdl-25794837

ABSTRACT

The concentrations of methane (CH4), non-methane hydrocarbons (NMHC), and carbon monoxide (CO) were measured at two urban locations (Guro (GR) and Nowon (NW)) in Seoul, Korea between 2004 and 2013. The mean amount fractions of CH4, NMHC, and CO, measured at GR over this period were 2.06±0.02, 0.32±0.03, and 0.61±0.05 ppm, respectively, while at NW they were 2.08±0.06, 0.33±0.05, and 0.54±0.06 ppm, respectively. The ratio of CH4 to the total hydrocarbon amount fraction remained constant across the study years: 0.82 to 0.90 at GR and 0.81 to 0.89 at NW. Similarly, stable ratios were also observed between NMHC and THC at the two sites. In contrast, the annual mean ratios for CH4/NMHC showed a larger variation: between 4.55 to 8.67 at GR and 4.25 to 8.45 at NW. The seasonality of CO was characterized by wintertime maxima, while for CH4 and NMHC the highest amount fractions were found in fall. The analysis of their long-term trends based on Mann-Kendall and Sen's methods showed an overall increase of THC and CH4, whereas a decreasing trend was observed for NMHC and CO.

15.
Environ Sci Process Impacts ; 17(3): 646-55, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25639653

ABSTRACT

The concentration of total gaseous mercury (TGM) was monitored, together with some key greenhouse gases (GHGs: carbon dioxide (CO2), methane (CH4), and water (H2O) vapor) at hourly intervals at a mountainous monitoring site close to the highly industrialized city of Seoul, Korea. Correlations between the concentrations of Hg and those of the greenhouse gases were examined to assess their source characteristics and responses to changes in meteorological conditions. The mean Hg levels in this study (3.58 ± 2.13 ng m(-3)) were considerably lower (by, e.g., 24.3%) than those measured previously in other comparable sites during 1999-2006 (4.73 ± 1.34 ng m(-3)). Accordingly, such a reduction in Hg levels suggests the effectiveness of the regulatory measures enforced over the years. The mean Hg level observed in this study is also lower (by approximately 5%) than those in other Asian locations. In contrast, the mean concentrations of the two most important GHGs (CO2 and CH4) were moderately higher than those of other locations across the world (by approximately 4-9%). The results of our analysis indicate that the behavior of Hg is strongly correlated with water vapor and CH4 in terms of their source characteristics, despite notable differences in their diurnal patterns.


Subject(s)
Air Pollutants/analysis , Carbon Dioxide/analysis , Environmental Monitoring , Mercury/analysis , Methane/analysis , Seoul
16.
Sensors (Basel) ; 14(8): 14399-410, 2014 Aug 07.
Article in English | MEDLINE | ID: mdl-25106022

ABSTRACT

N2O, which is emitted mainly from nitrogen decomposition via bacteria, livestock manure, agricultural fertilizer use, fossil fuel combustion and waste incineration, is classified as a substance that causes significant destruction of the ozone layer. The N2O measurement methods for these emission sources may be divided into chromatography, optical, and electrical current measurements. Chromatography has been widely utilized for analyzing N2O. However, up until now, few studies have been conducted on N2O using photoacoustic spectroscopy. Therefore, this study aimed to evaluate performance of photoacoustic spectroscopy in this regard based on laboratory and field test results. The repeatability of photoacoustic spectroscopy was measured at 1.12%, which is lower than the repeatability of 3.0% suggested by the ISO 1564 standard, so, it has shown an excellent repeatability. The detection limit was determined to be 0.025 ppm, and the response time was confirmed to be 3 min and 26 s. The results of comparison between these measurements and GC show that the latter has superior accuracy, but mobility and convenience are superior for PAS. On the contrary, GC has a continuous measurement limitation, but PAS makes it possible to conduct continuous measurements. Therefore, PAS can be extremely useful to confirm the characteristics of N2O emissions and to quantify their amount.


Subject(s)
Environmental Monitoring/methods , Nitrous Oxide/chemistry , Air Pollutants/analysis , Nitrogen/chemistry , Spectrum Analysis/methods
17.
Environ Sci Technol ; 47(18): 10541-7, 2013 Sep 17.
Article in English | MEDLINE | ID: mdl-23991835

ABSTRACT

Using biomass as a renewable energy source via currently available thermochemical processes (i.e., pyrolysis and gasification) is environmentally advantageous owing to its intrinsic carbon neutrality. Developing methodologies to enhance the thermal efficiency of these proven technologies is therefore imperative. This study aimed to investigate the use of CO2 as a reaction medium to increase not only thermal efficiency but also environmental benefit. The influence of CO2 on thermochemical processes at a fundamental level was experimentally validated with the main constituents of biomass (i.e., cellulose and xylan) to avoid complexities arising from the heterogeneous matrix of biomass. For instance, gaseous products including H2, CH4, and CO were substantially enhanced in the presence of CO2 because CO2 expedited thermal cracking behavior (i.e., 200-1000%). This behavior was then universally observed in our case study with real biomass (i.e., corn stover) during pyrolysis and steam gasification. However, further study is urgently needed to optimize these experimental findings.


Subject(s)
Carbon Dioxide/chemistry , Cellulose/chemistry , Xylans/chemistry , Zea mays , Biomass , Hot Temperature , Plant Leaves , Plant Stems , Renewable Energy , Steam
18.
Environ Sci Pollut Res Int ; 20(1): 461-8, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23001757

ABSTRACT

In this research, in order to develop technology/country-specific emission factors of methane (CH(4)) and nitrous oxide (N(2)O), a total of 585 samples from eight gas-fired turbine combined cycle (GTCC) power plants were measured and analyzed. The research found that the emission factor for CH(4) stood at "0.82 kg/TJ", which was an 18 % lower than the emission factor for liquefied natural gas (LNG) GTCC "1 kg/TJ" presented by Intergovernmental Panel on Climate Change (IPCC). The result was 8 % up when compared with the emission factor of Japan which stands at "0.75 kg/TJ". The emission factor for N(2)O was "0.65 kg/TJ", which is significantly lower than "3 kg/TJ" of the emission factor for LNG GTCC presented by IPCC, but over six times higher than the default N(2)O emission factor of LNG. The evaluation of uncertainty was conducted based on the estimated non-CO(2) emission factors, and the ranges of uncertainty for CH(4) and N(2)O were between -12.96 and +13.89 %, and -11.43 and +12.86 %, respectively, which is significantly lower than uncertainties presented by IPCC. These differences proved that non-CO(2) emissions can change depending on combustion technologies; therefore, it is vital to establish country/technology-specific emission factors.


Subject(s)
Air Pollutants/analysis , Methane/analysis , Nitrous Oxide/analysis , Power Plants/statistics & numerical data , Air Pollutants/standards , Air Pollution/statistics & numerical data , Methane/standards , Nitrous Oxide/standards , Republic of Korea , Uncertainty
19.
Chemosphere ; 89(11): 1384-9, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22784868

ABSTRACT

The emission concentrations of several chlorofluorocarbons (CFCs) were measured from a municipal waste treatment facility (located in Seoul, Republic of Korea) to investigate the emission characteristics of CFCs in the urban environment. To this end, a total of five CFCs (CFC-10, CFC-11, CFC-20, CFC-30, and CFC-113) were analyzed by the thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) method. The results of this study indicate that the formation of CFC-11 (8.21 ± 1.68 ppb in spring) and CFC-20 (3.92 ± 3.93 ppb in spring) proceeded very actively within the facility. Moreover, CFC-113 was also found in relatively high concentrations (3.34 ± 1.31 ppb in spring) in the treatment facility. Unlike other CFCs, CFC-10 was observed mainly at ambient (and reference) locations and one point inside the treatment facility. In conclusion, emissions of some important CFCs are a prominent process, as they were measured either frequently or abundantly both in winter and spring. It is further indicated that certain CFCs (like CFC-11 and CFC-30) are subject to highly significant seasonal variations.


Subject(s)
Air Pollutants/analysis , Chlorofluorocarbons/analysis , Environmental Monitoring , Refuse Disposal , Air Pollutants/chemistry , Air Pollution/statistics & numerical data , Chlorofluorocarbons/chemistry , Republic of Korea , Seasons
20.
ScientificWorldJournal ; 2012: 468214, 2012.
Article in English | MEDLINE | ID: mdl-22666126

ABSTRACT

In order to tackle climate change effectively, the greenhouse gas emissions produced in Korea should be assessed precisely. To do so, the nation needs to accumulate country-specific data reflecting the specific circumstances surrounding Korea's emissions. This paper analyzed element contents of domestic anthracite, calorific value, and concentration of methane (CH4) and nitrous oxide (N2O) in the exhaust gases from circulating fluidized bed plant. The findings showed the concentration of CH4 and N2O in the flue gas to be 1.85 and 3.25 ppm, respectively, and emission factors were 0.486 and 2.198 kg/TJ, respectively. The CH4 emission factor in this paper was 52% lower than default emission factor presented by the IPCC. The N2O emission factor was estimated to be 46% higher than default emission factor presented by the IPCC. This discrepancy can be attributable to the different methods and conditions of combustion because the default emission factors suggested by IPCC take only fuel characteristics into consideration without combustion technologies. Therefore, Korea needs to facilitate research on a legion of fuel and energy consumption facilities to develop country-specific emission factors so that the nation can have a competitive edge in the international climate change convention in the years to come.


Subject(s)
Air Pollutants/analysis , Coal/analysis , Methane/analysis , Nitrous Oxide/analysis , Power Plants , Republic of Korea
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