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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The Investigation of Ping-Tung Motorcycle Driving Cycle and Emission Factor

Lin, Zhi-Feng 20 July 2001 (has links)
During administer mobil source examine and control plan , we must estimate emission amount , curtail amount and curtail rate , to estimate the improve effection . But there has very few data of this aspect , especially real road driving pattern to calcul ate emission factory and amount . So it¡¦s necessary to proceed this aspect investigate. The investigate have two parts include driving pattern and emission factor . Determine item is CO , THC and NOx .The result of driving Ping-tung area have faster speed,longer navigate time and larger acceleration and deceleration . The result of emission factor¡GCO is 6.79 (¡Ó3.39) g/km , THC is 1.63 (¡Ó1.27) g/km and NOx is 0.13(¡Ó0.14) g/km . Idle emission CO is 1.03%(¡Ó1.19%)¡ATHC is 1400(¡Ó2138) ppm
2

Development of an ammonia emission protocol and preliminary emission factor for a central Texas dairy

Rose, Adam Joseph 30 September 2004 (has links)
A protocol was developed to measure ammonia emission concentrations from dairies using an isolation flux chamber. A hybrid dairy in Comanche county, Texas, was measured for one week each during August 2002 and January 2003. Sixty total ammonia samples were taken from the free stall barn, open lot, mixing tank, separated solids, compost, and two lagoons using the developed protocol. The ammonia concentration measurements were made using a chemiluminescence analyzer located inside a mobile laboratory. From the emission concentrations recorded, it was estimated that 9.68 metric tons of ammonia were produced from this dairy per year. An emission factor of 13.34 ± 28.80 kilograms per day per thousand head of cattle (kg/day/1000 head) was estimated for this dairy (±95% confidence intervals) during summer conditions. For winter conditions the emission factor was 12.05 ± 12.89 kg/day/1000 head. The 11% difference of the emission factors from summer to winter conditions was predominantly from the change in ambient and control volume temperatures (a mean difference of approximately 25 degrees Celsius), differences in source temperatures, and seasonal variability in husbandry. The adsorption of ammonia onto different polymer tubing used in pollutant stream conveyance was researched for possible systematic losses. Teflon and low density polyethylene (LDPE) were tested for ammonia losses with treatments of: temperature, length, and inlet concentration. Inlet concentration and temperature were significant factors used to describe ammonia adsorption for Teflon, whereas LDPE was also affected by tubing length. These factors were used to create a model to correct the summer dairy measurements for ammonia losses, resulting in an emission factor increase of 8.3% over the original value obtained from the flux chamber. A nitrogen mass balance was performed to estimate the amount of nitrogen available for ammonia formation as excreted - 177.5 kilograms per year per animal (wet basis). The amount of ammonia excreted per year was also estimated to be 26.63 kilograms per year. The measured ammonia emitted from the dairy was five times less than the ammonia excreted and thirty-six times less than the total nitrogen excreted.
3

Motorcycyles emission factors determined by dynamometric tests using real road driving cycles.

Wang, Wen-Jeng 24 June 2002 (has links)
Because of the economic development of Taiwan, population gathering and the habit of people using transports, these considerations have made vehicle grow up fast. Vehicles emitted a large amount of pollutant that has caused many air pollution occasions. The motive of this study is to understand the motorcycle driving cycle, amount of pollutant and emission factor in four areas ¡VTaipei, Taichung, Kaoshiung and Pingtung. But it is very poor on concerning study in Taiwan. It is necessary to go on the concerning investigation and to establish the driving cycle and the actual emission factor of mobile source of Taiwan. The experiment includes two parts: one is regional driving pattern that is selected by factor analysis from samples; the other is to get the concentration of the pollutant and to calculate emission factors of the one by using Dynamometer. The pollutants are carbon monoxide (CO), total hydrocarbon (THC) and nitrogen oxides (NOX). In this study, the emission factors of motorcycles of the four areas are ¡§Taipei: CO 8.24 g/km, THC 2.53 g/km, NOX 0.12 g/km, CO2 55.98 g/km, Taichung: CO 7.81 g/km, THC 2.28 g/km, NOX 0.12 g/km, CO2 54.31 g/km, Kaoshiung: CO 6.53 g/km, THC 1.62 g/km, NOX 0.13 g/km, CO2 54.03 g/km, and Pingtung: CO 6.79 g/km, THC 1.63 g/km, NOX 0.13 g/km, CO2 41.42 g/km.
4

Development of an ammonia emission protocol and preliminary emission factor for a central Texas dairy

Rose, Adam Joseph 30 September 2004 (has links)
A protocol was developed to measure ammonia emission concentrations from dairies using an isolation flux chamber. A hybrid dairy in Comanche county, Texas, was measured for one week each during August 2002 and January 2003. Sixty total ammonia samples were taken from the free stall barn, open lot, mixing tank, separated solids, compost, and two lagoons using the developed protocol. The ammonia concentration measurements were made using a chemiluminescence analyzer located inside a mobile laboratory. From the emission concentrations recorded, it was estimated that 9.68 metric tons of ammonia were produced from this dairy per year. An emission factor of 13.34 ± 28.80 kilograms per day per thousand head of cattle (kg/day/1000 head) was estimated for this dairy (±95% confidence intervals) during summer conditions. For winter conditions the emission factor was 12.05 ± 12.89 kg/day/1000 head. The 11% difference of the emission factors from summer to winter conditions was predominantly from the change in ambient and control volume temperatures (a mean difference of approximately 25 degrees Celsius), differences in source temperatures, and seasonal variability in husbandry. The adsorption of ammonia onto different polymer tubing used in pollutant stream conveyance was researched for possible systematic losses. Teflon and low density polyethylene (LDPE) were tested for ammonia losses with treatments of: temperature, length, and inlet concentration. Inlet concentration and temperature were significant factors used to describe ammonia adsorption for Teflon, whereas LDPE was also affected by tubing length. These factors were used to create a model to correct the summer dairy measurements for ammonia losses, resulting in an emission factor increase of 8.3% over the original value obtained from the flux chamber. A nitrogen mass balance was performed to estimate the amount of nitrogen available for ammonia formation as excreted - 177.5 kilograms per year per animal (wet basis). The amount of ammonia excreted per year was also estimated to be 26.63 kilograms per year. The measured ammonia emitted from the dairy was five times less than the ammonia excreted and thirty-six times less than the total nitrogen excreted.
5

Overall CO2 efficiency assessment for a low carbon energy system

Zheng, Zhanghua January 2014 (has links)
Decarbonization of the power sector is of great importance for the transition to a sustainable and low-carbon world economy. Estimating carbon efficiency in the power sector is a key step to grasp the impact of demand-side usage changes and evaluate their potential environmental benefits. In order to quantify the environmental benefits of demand-side usage changes, Average Emission Factor (AEF) and Marginal Emission Factor (MEF) have been proposed in the electrical power sector. AEF is defined as the ratio of the total CO2 emitted in the system to the total electricity generated. It is an effective factor for reporting on CO2 emissions at system level and on an average basis, but the current AEF model lacks clarity on the factors actually affecting the estimation. MEF is defined as the incremental change in carbon emissions as a result of a change in demand. However, previous MEF assessments did not consider key technical limitations, such as ramp-rate constraint for generators and network constraints, and carbon trading mechanisms. This thesis improves the estimation for both AEF and MEF and key achievements can be summarized as: 1). A novel model of estimating AEF, with its application to GB, US and China’s electricity system. 2). Improvement on conventional MEF model by considering ramp-rate constraint in dispatch order. 3). Sensitivity studies on MEF using current fuel prices and future fuel prices. 4). A new model of estimating MEF considering both the utilization level of generators and the carbon costs when determining the dispatch order. 5). The effect of power network on MEF estimation, with a comparison of congested scenarios and non-congested scenario.
6

Carbon Tax Based on the Emission Factor

Almutairi, Hossa 26 September 2013 (has links)
In response to growing concerns about the negative impact of GHG emissions, several countries such as the European Union have adopted a cap-and-trade policy to limit the overall emissions levels. Alternatively, other countries including Argentina, Canada, the United Kingdom, and United States have proposed an intensity-based cap-and-trade system that targets emission intensities, measured in emissions per dollars or unit of output. Arguably,intensity regulations can accommodate future economic growth, reduce cost uncertainty, engage developing countries in international efforts to mitigate climate change, and provide incentives to improve energy efficiency and to use less carbon-intensive fuels. This work models and studies a carbon tax scheme where policy makers set a target emission factor, which is used as an intensity measure, for a specific industry and tax firms if they exceed that limit. The policy aims to promote energy efficiency, alleviate the impact on low emitters, and allow high emitters some flexibility to comply. We examine the effectiveness of the policy in reducing the emission factor due to manufacturing and transportation. The major objective of this research is to provide policy makers with a decision support tool that can aid in investigating the impact of an intensity-based carbon tax on regulated sectors and in finding the tax rate that achieves a target reduction. Therefore, we first propose a social-welfare maximizing model that can serve as a tool to evaluate the economic and environmental impacts of the policy. We compare the outcomes of the intensity-based tax and other existing environmental policies; namely, carbon tax imposed on overall emissions, cap-and-trade systems, and mandatory caps using case studies that are built within the context of the cement industry. The effectiveness of the policy is measured by achieving a balance between the target emission factor and the social welfare. To find the optimal tax rate that achieves a target reduction, we propose a bilevel programming model where at the upper level, the government sets a target emission factor for the industry and taxes firms if they exceed that target, and at the lower level, the industry sets output levels that maximize social welfare. In the design of the policy, the government takes into account the decisions of the producers regarding fuel types and production quantities as well as the decisions of the market regarding demand. To evaluate the effectiveness of the policy, we build case studies in the context of cement industry. The policy is found to be effective in reducing the CO2 emissions by opting for a less carbon-intensive fuel with a little impact on social welfare. To examine the effectiveness of the intensity-based carbon tax on reducing CO2 emissions from transportation, which is a major supply chain activity, we finally propose a bilevel program where at the upper level the government decides on the tax rate and at the lower level firms decide on the design of their supply chain and truck types. The policy is found to be effective in inducing firms to reduce their emission factors and consequently reducing the overall emissions.
7

Saving Energy and Reducing Polycyclic Aromatic Hydrocarbons Emissions from a Heavy-Duty Diesel Engine by H2/O2 Addition to the Combustion Chamber

Huang, Yi-Sheng 23 June 2011 (has links)
The emission of polycyclic aromatic hydrocarbons (PAHs) from the diesel engine on a dynamometer by mixing ratio of the fuel (H2/O2 /diesel) was investigated. The engine was operated at a one load steady-state condition of 1,600 rpm with torque and power outputs of 145 Nm and 24.5 kW. In this condition, the measurement of the mixing ratio of the fuel (H2/O2 /diesel) was first recorded without any induction of H2/O2 mixture (Base) into the engine. Then, seven flow rate levels of H2/O2 mixture were used by 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min, and 70 L/min, respectively. The concentrations of total PAHs were 106.58, 101.89, 95.30, 90.70, 85.98, 82.35, 72.38, and 67.30 £gg/m3, respectively for Base (0 L/min), 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min, and 70 L/min of H2/O2 mixture. The emission factor of total PAHs were 6.00, 5.73, 5.36, 4.99, 4.84, 4.50, 4.07, and 3.78 mg/bhp-hr, respectively for Base (0 L/min), 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min, and 70 L/min of H2/O2 mixture. The removal rate of total PAHs were 4.4%, 10.6%, 14.9%, 19.3%, 22.7%, 32.1%, and 36.9%, respectively for 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min, and 70 L/min of H2/O2 mixture. This result showed using H2/O2 mixture significantly reduced emissions of PAHs. As the regulated harmful matters, using H2/O2 mixture, CO¡BCO2¡BTHC and PM decreased, whereas the NOx emission increased. The energy saving of the fuels (H2/O2 /diesel), the total oil equivalents combined by fuel consumption of diesel engine and electricity consumption of H2/O2 generator, were 2.42, 2.49, 2.50, 2.48, 2.51, 2.35, 2.18, and 2.17 for Base (0 L/min), 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min, and 70 L/min of H2/O2 mixture. The result showed that reduced saving energy of the fuel (H2/O2 /diesel) by 3.2% for 50 L/min, 9.8% for 60 L/min, and 10.4% for 70 L/min, respectively.
8

Saving Energy and Reducing Carbonyl Compounds Emissions using H2/O2 Alternative Fuel on a Heavy-Duty Diesel Engine

Wang, Ying-Lan 23 June 2011 (has links)
This research carries out all tests in diesel engine takes neat diesel and hydrogen+oxygen (H2/O2) which is used as an additive (H2/O2 mixture: 10 to 70 L/min, interval 10 L/min) in a stable state condition (engine was operated at one load steady-state condition of 1600 rpm with torque and power outputs of 145 Nm and 24.5 kW, respectively). Characteristics of carbonyls emissions from H2/O2 as an additive were investigated in a HDDE (heavy-duty diesel engine) and compared with those from neat diesel, contains the concentration, emission factor and elimination efficiency, whole of change tendency in order to help the understanding of diesel engine pollutant emissions, and appraises energy conservation of benefit which add to H2/O2. The regulated pollutants emission, using H2/O2 mixture (10 to 70 L/min), THC, CO, CO2 and PM emission all increased while H2/O2 showed signs of decrease; on the contrary, NOx emission increased while H2/O2 increased. Regarding Carbonyls emissions, the total carbonyls concentration of diesel engine take neat diesel was 3218.02 £gg/m3 and the emission factors for diesel engine take neat diesel were 180.882 mg/bhp-hr and 788.061 mg/L-fuel, respectively. When H2/O2 mixture was added, total carbonyls concentration of 3068.28, 3006.42, 2823.10, 2707.06, 2500.54, 2216.87 and 2178.27 mg/m3 were 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min and 70 L/min, respectively. The emission factor may be divided into mg/bhp-hr and mg/L-fuel; the emission factor of total carbonyls were 231.36¡B226.18¡B211.41¡B203.14¡B186.98¡B167.17 and 164.23 mg/bhp-hr, respectively; the emission factor of total carbonyls were 764.95¡B755.15¡B719.97¡B707.36¡B704.40¡B694.27 and 690.47 mg/L-fuel, respectively. Increases in H2/O2 can reduce total carbonyls emissions with an eliminating efficiency rate of 4.7, 6.6, 12.3, 15.9, 22.3, 31.1 and 32.3%, respectively. Energy conservation of appraisal increase H2/O2, diesel equivalent sun of fuel consumption of diesel engine and electricity consumption of H2/O2 generator, namely can distinguish that its energy consumption, whole consumes were 2.51, 2.58, 2.59, 2.57, 2.60, 2.43, 2.26 and 2.25, respectively. When compared with neat diesel, result showed in H2/O2 from 10 L/min to 40 L/min, diesel equivalent increased while H2/O2 showed increase; but in H2/O2 from 50 L/min to 70 L/min reflected in a gradual decrease in diesel equivalent, indicating that increases in H2/O2 can effectively achieve energy conservation. The result showed that energy conservation was 3.4%, 10.0% and 10.6% for 50 L/min, 60 L/min and 70 L/min, respectively. The result indicated H2/O2 was 60 L/min when energy conservation benefit was most remarkable, therefore this had the best energy conservation.
9

Emission Characteristics of Polycyclic Aromatic Hydrocarbons from a Heavy-Duty Diesel Engine mixed with constant H2/O2 and diesel/Biodiesel blends

Wu, Shin-Yi 26 June 2012 (has links)
This study investigated emission characteristics of polycyclic aromatic hydrocarbons (PAHs) and reductions of regulated harmful matters using Premium diesel fuel (PDF), mixed with a 60 L/min flow rate of H2/O2 mixture and blended with biodiesel 5% (B5), 10% (B10), 20% (B20), and 30% (B30). The diesel engine was operated at steady-state condition of 1,600 rpm, with torque and power outputs of 145 Nm and 24.5 kW, respectively. Measured results show that the emission concentrations of total PAHs were 22.42, 20.11, 17.28, 13.45, and 13.13 £gg/m3 for B0, B5, B10, B20, and B30, respectively, with corresponding emission factors of total PAHs being 1334.53, 1198.82, 986.05, 771.93, and 748.82 £gg/bhp-hr, and reductions of total PAHs being 10.3, 22.9, 40.0, and 41.4%. The results indicated that using biodiesel can reduce PAH emissions. However, the emission factors of carbon monoxide (CO) and total hydrocarbons (THC) were decreased by adding biodiesel, but those of carbon dioxides (CO2), nitrogen dioxides (NOx), and particulate matter (PM) were increased. Annual emissions of total PAHs were estimated to be 140.05, 126.92, 105.21, 81.97, and 79.86 ton/year for B0, B5, B10, B20 and B30, respectively, decreasing with increasing biodiesel. Also, the corresponding annual emissions of BaPeq were 5.88, 5.62, 3.50, 3.03, and 2.83 ton/year, respectively.
10

The dust emission coefficients and emission rates in construction site in Kaohsiung City

Hsieh, Tao-Fan 28 June 2012 (has links)
This study collected relevant data of construction sites between January 1990 and December 2011 to estimate the emission factors of various construction projects for Kaohsiung City using Jhang¡¦s equations. The emission factors of various construction projects are as follows: about 0.121 kg/m2/month for reinforced concrete construction, about 0.141 kg/m2/month for steel constructed buildings, 0.228 kg/m2/month for road (tunnel) works, 0.126 kg/m2/month for bridge works, 0.101 tons/ha/month for regional construction projects, and 0.223 kg/m2/month for others. Based on these emission factors, the total fugitive dust emissions for 2,011 construction projects is estimated to be about 22,087.98 tons, and the exposure of per unit area to the fugitive dust pollution is approximately 11.98 ton/km2/month. The total fugitive dust emissions of 2,011 construction projects is estimated about 10528.14 tons (based on Kaohsiung City construction information database). According to the Department of Land, Kaohsiung City Government, Kaohsiung city is 27.8 kilometers from south to north, 10.4 kilometers from west to east, and the administrative area is 153.6029 square kilometers. The exposure of per unit area to the fugitive dust pollution is about 5.71 ton/km2/months.

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