scholarly journals Analysis of Main Factors for CH4 Emission Factor Development in Manufacturing Industries and Construction Sector

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1220
Author(s):  
Seongmin Kang ◽  
Seonghum Cho ◽  
Joonyoung Roh ◽  
Eui-chan Jeon

This study has statistically analyzed the effect of boiler type and model year on CH4 emission factors, focusing on liquefied natural gas (LNG)—the most commonly used fuel in South Korean manufacturing combustion facilities. Samples were collected from the boilers of 39 manufacturing combustion facilities that use LNG fuel. The CH4 emission factors were developed based on 4 overhead fire-tube boilers, 14 once-through boilers, 14 vertical boilers with vertical water tubes, and 7 other boilers. This resulted in an average value of 0.11 CH4 kg/TJ, which is considerably lower than the Intergovernmental Panel on Climate Change (IPCC) 1996 guidelines(G/L) emission factor of 5 CH4 kg/TJ currently used in South Korea. In the Kruskal–Wallis test results, the significance probability was greater than 0.05 for the boiler types and ages, and there was no major difference in the average distributions, according to the boiler type or age. Therefore, according to the results of this study, the differences in the CH4 emission factors according to the boiler types and ages are not statistically large, and it was determined that there is no major difference even when the emission factors are applied to different fuel types. However, there was a major difference when the developed factors were compared to the CH4 emission factor proposed by the IPCC. Thus, there is a need to develop manufacturing combustion CH4 emission factors that reflect national characteristics.

2021 ◽  
Vol 21 (11) ◽  
pp. 8557-8574
Author(s):  
Elizabeth B. Wiggins ◽  
Arlyn Andrews ◽  
Colm Sweeney ◽  
John B. Miller ◽  
Charles E. Miller ◽  
...  

Abstract. Recent increases in boreal forest burned area, which have been linked with climate warming, highlight the need to better understand the composition of wildfire emissions and their atmospheric impacts. Here we quantified emission factors for CO and CH4 from a massive regional fire complex in interior Alaska during the summer of 2015 using continuous high-resolution trace gas observations from the Carbon in Arctic Reservoirs Vulnerability Experiment (CRV) tower in Fox, Alaska. Averaged over the 2015 fire season, the mean CO / CO2 emission ratio was 0.142 ± 0.051, and the mean CO emission factor was 127 ± 40 g kg−1 dry biomass burned. The CO / CO2 emission ratio was about 39 % higher than the mean of previous estimates derived from aircraft sampling of wildfires from boreal North America. The mean CH4 / CO2 emission ratio was 0.010 ± 0.004, and the CH4 emission factor was 5.3 ± 1.8 g kg−1 dry biomass burned, which are consistent with the mean of previous reports. CO and CH4 emission ratios varied in synchrony, with higher CH4 emission factors observed during periods with lower modified combustion efficiency (MCE). By coupling a fire emissions inventory with an atmospheric model, we identified at least 34 individual fires that contributed to trace gas variations measured at the CRV tower, representing a sample size that is nearly the same as the total number of boreal fires measured in all previous field campaigns. The model also indicated that typical mean transit times between trace gas emission within a fire perimeter and tower measurement were 1–3 d, indicating that the time series sampled combustion across day and night burning phases. The high CO emission ratio estimates reported here provide evidence for a prominent role of smoldering combustion and illustrate the importance of continuously sampling fires across time-varying environmental conditions that are representative of a fire season.


2018 ◽  
Vol 53 (6) ◽  
pp. 657-663 ◽  
Author(s):  
Luana Goulart Sardá ◽  
Martha Mayumi Higarashi ◽  
Rodrigo da Silveira Nicoloso ◽  
Paulo Armando Victória de Oliveira ◽  
Camila Falkoski ◽  
...  

Abstract: The objective of this work was to contribute to the establishment of a baseline for the methane emission factor for the management of swine manure, considering the current practice of raw manure storage in two open deposits in parallel, in Southern Brazil. Methane (CH4) emissions were continuously measured in three PVC tanks of 3 m3, during 180 days, in the summer. As the content of volatile solids of pig slurry ran out in approximately 130 days, the CH4 emission factor was calculated as B0= 0.48 m3kg-1VS. Although this value is higher than the B0 estimated by Intergovernmental Panel on Climate Change for Latin America (0.29 m3 kg-1 VS), it is in agreement with the B0 estimated for developed countries (0.45 and 0.48 m3 kg-1 VS, for the US and EU, respectively). The graphic of accumulated CH4-C emission x time fitted a sigmoidal, kinetic model (r2= 0.998) that showed a good correlation when tested with the emission data collected from a slurry deposit, under field conditions, in winter. This suggests that the model reproduces the CH4 emission kinetics in the region. By applying the reviewed state law rules (retention time of 50 instead of 120 days), estimates by the sigmoidal equation show that it is possible to reduce in more than 80% methane gas emission.


2020 ◽  
Author(s):  
Elizabeth B. Wiggins ◽  
Arlyn Andrews ◽  
Colm Sweeney ◽  
John B. Miller ◽  
Charles E. Miller ◽  
...  

Abstract. With recent increases in burned area within boreal forests that have been linked to climate warming, there is a need to better understand the composition of emissions and their impact on atmospheric composition. Most previous studies have estimated boreal fire emission factors from daytime samples collected via aircraft near fire plumes or at the surface near actively burning fires. Here we quantified emission factors for CO and CH4 from a massive regional fire complex in interior Alaska during the summer of 2015 using continuous high-resolution trace gas observations from the CRV tower (Fox, AK). Averaged over the 2015 fire season, the CO/CO2 emission ratio was 0.138±0.048 and the CO emission factor was 145±50 g CO per kg of dry biomass consumed. The CO/CO2 emission ratio was about 35 % higher and more variable than most previous aircraft-based estimates for fresh wildfire emissions. The mean CH4/CO2 emission ratio was 0.010±0.003 and the CH4 emission factor was 6.05±2.09 g CH4 per kg of dry biomass consumed, with means similar to previous reports. CO and CH4 emission factors varied in synchrony, with higher CH4 emission factors observed during periods with lower modified combustion efficiency (MCE). By coupling a fire emissions inventory with an atmospheric model, we identified that at least 35 individual fires contributed to trace gas variations measured at the CRV tower, representing a significant increase in sampling compared to the number of boreal fires measured in all previous boreal forest fire work. The model also indicated that typical mean transit times between trace gas emission and tower measurement were 1–3 days, indicating that the time series sampled combustion across day and night burning phases. The high and variable CO emission factor estimates reported here provide evidence for a more prominent role of smoldering combustion, highlighting the importance of continuously sampling of fires across time-varying environmental conditions that are representative of typical burning conditions.


2020 ◽  
Vol 60 (13) ◽  
pp. 1668
Author(s):  
P. W. Ndung’u ◽  
B. O. Bebe ◽  
J. O. Ondiek ◽  
K. Butterbach-Bahl ◽  
L. Merbold ◽  
...  

National greenhouse-gas (GHG) inventories in most developing countries, and in countries in Sub-Saharan Africa in particular, use default (Tier I) GHG emission factors (EFs) provided by the Intergovernmental Panel on Climate Change (IPCC) to estimate enteric methane (CH4) emissions from livestock. Because these EFs are based on data primarily from developed countries, there is a high degree of uncertainty associated with CH4 emission estimates from African livestock systems. Accurate Tier II GHG emission reporting from developing countries becomes particularly important following the Paris Climate agreement made at COP21, which encourages countries to mitigate GHG emissions from agricultural sources. In light of this, the present study provides improved enteric CH4 emission estimates for cattle in Nandi County, Western Kenya, representing a common livestock production system found in East Africa. Using the data from measurements of liveweight and liveweight change, milk production and locomotion collected from 1143 cattle in 127 households across 36 villages over three major agro-ecological zones covering a full year, we estimated total metabolic energy requirements. From this and assessments of digestibility from seasonally available feeds, we estimated feed intake and used this to calculate daily CH4 production by season, and, subsequently, created new EFs. Mean EFs were 50.6, 45.5, 28.5, 33.2 and 29.0 kg CH4/head.year for females (>2 years), males (>2 years), heifers (1–2 years), young males (1–2 years) and calves (4 emissions in some African livestock systems.


2018 ◽  
Vol 10 (10) ◽  
pp. 3448 ◽  
Author(s):  
Changsang Cho ◽  
Seongmin Kang ◽  
Minwook Kim ◽  
Yoonjung Hong ◽  
Eui-chan Jeon

Thermal power plants are a large source of greenhouse gas emissions among energy industry facilities. Emission factors for methane and nitrous oxide depend on combustion technologies and operating conditions and vary significantly with individual thermal power plants. Due to this variability, use of average emission factors for these gases will introduce relatively large uncertainties. This study determined the CH4 emission factors of thermal power plants currently in operation in Korea by conducting field investigations according to fuel type and type of combustion technique. Through use of the Monte Carlo simulation, the uncertainty range for the CH4 emission factor was determined. The estimation showed, at the 95% confidence level, that the uncertainty range for CH4 emission factor from a tangential firing boiler using bituminous coal was −46.6% to +145.2%. The range for the opposed wall-firing boiler was −25.3% to +70.9%. The range for the tangential firing boiler using fuel oil was −39.0% to 93.5%, that from the opposed wall-firing boiler was −47.7% to +201.1%, and that from the internal combustion engine boiler was −38.7% to +106.1%. Finally, the uncertainty range for the CH4 emission factor from the combined cycle boiler using LNG was −90% to +326%.


Author(s):  
Wirda Linda

This research is motivated by the low desire of students in writing travel reports. The lack of students' knowledge of the report concept, the lack of students' knowledge of the 5W + 1H report points of good and correct language, the lack of students' knowledge of the spatial, time and topic pattern and not yet reached KKM 75. The method used by the teacher has not been interesting, lecture method. The purpose of this study is to describe the skills of writing travel reports by using Round Club learning model which is viewed from the aspect of understanding the report concept, the use of 5W +1H report points, the spatial, time, and topic pattern.The population of this study is the students of class V Lessons Year 2017/2018 which amounted to 2 classes with the number 80. The sample of research as much as two classes taken by the sample of propotional.Class V.1 as experimental class and class V.2 as control class. The research instrument used is performance test. Provide an assessment by specifying the subject of the 5W + 1H report, as well as the spatial, time and topic pattern. Data were analyzed by 't' test by first testing normality, homogeneity, and hypothesis testing.The results showed that the average control class 68 with more than enough qualifications with standard deviation 16.96. 83 experimental class with good qualification and standard deviation of 15.42 and there is a significant influence on the result of writing skill of class V SDN 01 Nagari Bukik SikumpaSubdistrict, Lima Puluh Kota. This is evidenced by the average value of writing skills in the experiment class higher than the average value in the control class. Normality test results indicate that the two sample classes of  Lo  values in the control class -0.2141 are smaller than the normal 0.190 Lt distributed. Homogeneity test results that the variation of this study is homogeneous at a real level of 0.05, because Ftable 2.16 > Fhitung 1.21 and the results of data analysis then obtained = 2.78 > 1.70 t table, so H0 rejected and H1 accepted. It can be concluded that there is Influence. Using  Learning  Model of Student Group Writing  Skills Travel Report of students of class V SDN 01 Nagari Bukik Sikumpa Subdistrict, Kabupaten Lima Puluh Kota.KeyWords: model pembelajaran round club, menulis laporan perjalanan.


2021 ◽  
Vol 13 (4) ◽  
pp. 2197
Author(s):  
Seongmin Kang ◽  
Joonyoung Roh ◽  
Eui-chan Jeon

NH3 is one of the major substances contributing to the secondary generation of PM2.5; therefore, management is required. In Korea, the management of NH3 is insufficient, and the emission factor used by EPA is the same as the one used when calculating emissions. In particular, waste incineration facilities do not currently calculate NH3 emissions. In the case of combustion facilities, the main ammonia emission source is the De-NOx facility, and, in the case of a power plant with a De-NOx facility, NH3 emission is calculated. Therefore, in the case of a Municipal Solid Waste (MSW) incinerator with the same facility installed, it is necessary to calculate NH3 emissions. In this study, the necessity of developing NH3 emission factors for an MSW incinerator and calculating emission was analyzed. In addition, elements to be considered when developing emission factors were analyzed. The study found that the NH3 emission factors for each MSW incinerator technology were calculated as Stoker 0.010 NH3 kg/ton and Fluidized Beds 0.004 NH3 kg/ton, which was greater than the NH3 emission factor 0.003 NH3 kg/ton for the MSW incinerator presented in EMEP/EEA (2016). As a result, it was able to identify the need for the development of NH3 emission factors in MSW incinerators in Korea. In addition, the statistical analysis of the difference between the incineration technology of MSW and the NH3 emission factor by the De-NOx facility showed a difference in terms of both incineration technology and De-NOx facilities, indicating that they should be considered together when developing the emission factor. In addition to MSW, it is believed that it will be necessary to review the development of emission factors for waste at workplaces and incineration facilities of sewage sludge.


2008 ◽  
Vol 5 (5) ◽  
pp. 1215-1226 ◽  
Author(s):  
D. Weymann ◽  
R. Well ◽  
H. Flessa ◽  
C. von der Heide ◽  
M. Deurer ◽  
...  

Abstract. We investigated the dynamics of denitrification and nitrous oxide (N2O) accumulation in 4 nitrate (NO−3) contaminated denitrifying sand and gravel aquifers of northern Germany (Fuhrberg, Sulingen, Thülsfelde and Göttingen) to quantify their potential N2O emission and to evaluate existing concepts of N2O emission factors. Excess N2 – N2 produced by denitrification – was determined by using the argon (Ar) concentration in groundwater as a natural inert tracer, assuming that this noble gas functions as a stable component and does not change during denitrification. Furthermore, initial NO−3 concentrations (NO−3 that enters the groundwater) were derived from excess N2 and actual NO−3 concentrations in groundwater in order to determine potential indirect N2O emissions as a function of the N input. Median concentrations of N2O and excess N2 ranged from 3 to 89 μg N L−1 and from 3 to 10 mg N L−1, respectively. Reaction progress (RP) of denitrification was determined as the ratio between products (N2O-N + excess N2) and starting material (initial NO−3 concentration) of the process, characterizing the different stages of denitrification. N2O concentrations were lowest at RP close to 0 and RP close to 1 but relatively high at a RP between 0.2 and 0.6. For the first time, we report groundwater N2O emission factors consisting of the ratio between N2O-N and initial NO−3-N concentrations (EF1). In addition, we determined a groundwater emission factor (EF2) using a previous concept consisting of the ratio between N2O-N and actual NO−3-N concentrations. Depending on RP, EF(1) resulted in smaller values compared to EF(2), demonstrating (i) the relevance of NO−3 consumption and consequently (ii) the need to take initial NO−3-N concentrations into account. In general, both evaluated emission factors were highly variable within and among the aquifers. The site medians ranged between 0.00043–0.00438 for EF(1) and 0.00092–0.01801 for EF(2), respectively. For the aquifers of Fuhrberg and Sulingen, we found EF(1) median values which are close to the 2006 IPCC default value of 0.0025. In contrast, we determined significant lower EF values for the aquifers of Thülsfelde and Göttingen. Summing the results up, our study supports the substantial downward revision of the IPCC default EF5-g from 0.015 (1997) to 0.0025 (2006).


2019 ◽  
Vol 1 (2) ◽  
pp. 107
Author(s):  
Frindly Makarawung ◽  
I Dewe Ketut Anom ◽  
John Lombok

This research aims to determine the effect of mind mapping learning methods on the basic laws of chemistry toward learning outcomes of students of class X MIPA in SMA Negeri 2 Langowan. The sample used in this study were all students of class X MIPA of SMA Negeri 2 Langowan. This research uses an experimental method, with the research method used is Quasi Experiment  with Nonequivalent Control Group Design design. The research data were obtained from post-test results. Obtained the average value of student learning outcomes Experiment class is 85. The results showed the value of tcount = 15.7> ttable = 2.21, so H0 was rejected and H1 was accepted. Based on the results of the research it can be concluded that there is an influence on student learning outcomes on the basic laws of chemistry using mind mapping learning methods.


Author(s):  
Yanti Fitria

This study aimed to describe effecitivity of the learning outcome IPA using inquiry method. This type of research is the Classroom Action Research (CAR). Research procedures conducted through four stages, namely planning, implementation, observation, and reflection. The study uses a qualitative and quantitative approach. Subjects were teachers and students of fourth class in elementary school 08 Padang City. Data was obtained from the results of observations and test results of learning. The research was conducted by two cycles and each cycle consisting of two meetings. The results of the research that has been conducted every cycle seen an increasein the average value of student learning outcomes are: (a) the cognitive aspects of 75 to 93, (b) the affective aspects of 74 to 95, and (c) psychomotor aspects from 76 to 94. It can be concluded that the CAR using the inquiry method can improve learning outcomes of science fourth grade students of fourth class in the state elementary school 08 Padang City.Key words: Learning competency; science learning; inquiry method


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