Waste pressure recovery provides a potential for electrical energy generation and GHG and air pollutant emissions reduction by decreasing the load of power plant. For this purpose, a computational model based on the exergy analysis is presented for the case of pressure break-down in Joule-Thomson process. All the calculations are based upon real-world operation conditions. It was found that the pressure-break has strong effects on the exergy losses in the Joule-Thomson process. By investigating the use of a turbo- expander instead of a commercial valve, exergy analysis and economical evaluations have been carried out. The pressure break- down process was analyzed with initial pressure about 95 bars and final pressure 74 bars. The results showed that the exergy loss is higher than 35 MW in all months for the present case study, and it is possible to recover about 1.9 MW of energy loss. It was also found that about 16900MWh of electrical energy may be produced by recovering the energy of waste pressure, which decreases the load and gas consumption in the refinery power plant annually. Concerning the emission reduction, 12056 ton of CO2e of GHG and 54.6 ton of air pollutant emissions are reduced by the presented energy recovery. The IRR and NPV are estimated to be about 25.51 % and 929571 USD, respectively, in a ten-year period. Sensitive analysis on economical results of each state is conducted, and the results showed that installation of a turbo-expander, instead of a pressure-break valve, appears to be really effective. Finally, it is concluded that developing the proposed idea will promote the use of clean and highly efficient technologies to generate electricity, with low negative impact on the environment.
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underline that, in general, the average velocity of traffic flow is larger in the FI model, such as it is shown in the plots we presented in the right column of the last row of Figure 6. These results are consequences of the dynamical rules of the FI traffic cellular automaton, where the particles can increase their velocities faster than in the NS model, and where the stochastic delay only applies to the high-speed cars. As we will show in Section 3.2, this behavior has an important consequence in relation with the air pollutant emissions of the traffic flows de- scribed by these models.
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A novelty of automating the plume identification tech- nique is that a large number of plumes can be identified and captured. By maximizing the sampling size, more vehi- cles can be represented by the measurements, which is use- ful when assessing the heterogeneity of emissions and cal- culating the fleet EFs. Although method validation for site- specific conditions requires initial testing, data processing can be completed on the order of minutes, removing the time limitation of processing large data sets. In this study, the technique was validated for differences in manual versus automated identification and integration; dilution effects; and sensitivity analysis of the method in order to test the repeata- bility of the calculated EFs. Comparison with previous study EF values is used to evaluate this methodology as well as potential differences in fleet EFs. This study also presents high-time-resolution measurements of VOCs using a pro- ton transfer reaction time-of-flight mass spectrometer (PTR- TOF-MS). While the PTR-TOF-MS has been deployed in the near-road environment (DeWitt et al., 2015), a novelty in this study is the application of this instrument to individ- ual plume EF measurements. Three applications of the au- tomated plume-by-plume approach are examined: (1) sepa- ration of individual plumes based on co-emitted pollutants, (2) estimation of the relative contributions of higher emitting vehicles to the overall emissions detected at the site, and (3) evaluation of local emissions regulation program.
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Surprisingly, the electricity sector is not identified as a key industry, even though its share of emissions is high (see table 2). One interpretation of this result is that air pollution emissions from the electricity sector strongly depend on the method of power generation. Air pollution is emitted from thermal power generation , but little air pollution is emitted from hydro and nuclear power generation. Electricity generation portfolio s are diverse among the countries in our sample and are more strongly affected by the characteristics of the geography, resources, and disaster conditions than by the economic development stage. Therefore, the electricity sector does not exhibit an EKC relationship and is not a key industry in air pollution emissions.
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The dispersion models were used to estimate or predict the concentration of air pollutants or toxins emitted from sources such as industrial plants, vehicular traffic or accidental chemical re- leases. In this study, the Industrial Source Complex Short Term (ISCST3) emission dispersion model was used to measure the ground level concentration of criteria air pollutants within 50 km radius of location. This model considered emissions from major point sources of pollutants in four exist- ing and twenty-three proposed Nigeria petroleum refineries. The obtained ground level concen- tration for 24-hr averaging periods of the criteria air pollutants at sensitive receptor around each of the refineries was compared with the National Ambient Air Quality Standards (NAAQS) of Nige- ria, World Bank and World Health Organization (WHO) to determine their level of compliance. The highest ground level concentration predicted to be 450 - 1875 µg/m 3 for 24-h averaging pe-
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Air quality permit No. 03973R39, found in Appendix A, was issued to SELEE Corporation on February 13, 2018 and is valid until January 31, 2026. Permit condition A8 describes testing requirements for the Cast Shop RTO. Under provisions of North Carolina General Statute 143- 215.108 and in accordance with 15A NCAC 2D .0605, SELEE is required to demonstrate compliance with emission limits for a natural gas-fired RTO serving a natural gas-fired roller hearth furnace. High temperature firing of polyurethane foam is the primary emission source in the process. The polyurethane foam completely burns off when it reaches a firing temperature of about 300 °F. The furnace typically operates at a temperature of about 1450 °F in the hottest zone. It takes around 30 minutes for a part to travel from the entrance to the exit of the kiln with a typical roller speed of 62 cm per second. The process is permitted to burn 194 pounds of
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Not only China government takes strict measure to control power plant’s air pollutants emissions and pay attention to the monitoring and management of thermal generator sets , so as to prevent air pollution, but also several mitigation technologies are adopted to reduce the values. The most pronounced technologies are filtering stack emissions using various industrial dust collectors, flue gas desulfurization (FGD) and denitrition systems [7-9]. Henan Province with one of the largest coal consu- mption is also one of the largest air pollutant emission ar- ea in China. To supply a clear emission picture of power sector, since 2005, Henan had shut down 9.78 million kW of small thermal power units, and by the end of 2008, all of its coal-fired power units had been equipped with desulfurization facilities, being able to reduce SO 2 by
There are still few research projects in the literature that have included a large number of urban components into emission scenarios dedicated to AQMs (Manins, 1995; Mar- quez and Smith, 1999; Martins, 2012; De Ridder et al., 2008). Prospective modeling research in the 2000s has re- vealed the determining role of mobility and city configura- tion (considered as the spatial organization of buildings, ser- vices and networks) in the exposure of individuals, but the study focused on academic situations (Borrego et al., 2006). However, over the last decade, social components have pro- gressively been integrated into urban emissions models, such as TASHA-MATSIM-MOBILE6.2C (Hao et al., 2010) and TRANUS-TREM (Bandeira et al., 2011), which are now able to quantify the impact of urban policies on road traffic emis- sions through carpooling, transportation fleet technology and individual modal choice. The strength of these models is linked to the implementation of a microsimulation approach based on individual choice, which depends on economic pa- rameters. However, most of the applications focused on road traffic emissions only (Hatzopoulou et al., 2008; Hülsmann et al., 2014), whereas in the current context that places partic- ular emphasis on the emerging concept of sustainable cities, it is necessary to take into account all air pollutant emissions related to energy consumption, insofar as they interact with air quality and climate change. In particular, there is a need to also take into account small combustion emissions (both residential and commercial) and their related policies to go further in the realism of the urban scenarios and to address the issue of air quality levers in a more holistic manner.
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To estimate the energy production and financial feasibility of the hypothetical PV plant, this study uses RETScreen software. RETScreen was created in 1996 by Natural Resources Canada’s Canmet Energy Research Center to provide low- cost preliminary assessments of RE projects. Independent reviews of RETScreen software validate its results all reporting RETScreen calculations to be within 0% - 6% of actual energy production . Solar irradiation in the area are taken from the NASA website of Surface meteorology and solar energy . To estimate the amount of carbon dioxide emissions avoided, the RETScreen predictions of the energy production of the PV plant are used to estimate the amount by which energy production from all the diesel plants in Sabah could decrease over the pe- riod of 10 years. Annual emissions data obtained from the power plant are used to estimate the air pollutant emissions avoided when a portion of the diesel plants’ energy production is replaced with PV energy based on 2 scenarios:
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Air quality data has been recorded in Malaysia since 1996 and the huge amount of data usually presented in the form of text information. Thus, air quality information are difficult to be reviewed, especially for the public understanding. Moreover, the public, especially those in high risk groups such as asthmatic individuals, children, and elderly, need to be alerted beforehand about the cases of poor air quality. Therefore, to implement air quality management and public warning strategies for pollution levels, a reasonably accurate forecasts of air quality is necessary. This can be achieved by using forecasting. Evaluation of performances are also important to find the best forecast performance. Thus, using the common error magnitude measurements is not enough to assess air quality. Index measurements are also important to evaluate the performance of air quality forecasting, because if the forecast fails to effectively predict poor air quality, it could cause a huge negative impact not only to the public health but also to the economy. Missing data is another problem that occurs when recording data due to many reasons such as instrument malfunction for a period of time. The results of air quality models and forecast could be influenced by considering the incomplete series of recorded data as an input in the analysis. Therefore, the estimations to replace missing values are always important in air quality studies.
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ABSTRACT A short-term study was conducted with a view to assess the ambient air quality in the surroundings area of compost plant at Okhla, Delhi. Three selected locations viz., CRRI Campus, Hazi Colony, and Gaffar Manzil were selected during the month of November 2008. The study revealed that 24 hourly average concentration of respirable suspended particulate matter (RSPM) at all selected locations were alarmingly high as compared to National Ambient Air Quality Standards (NAAQS) specified by Central Pollution Control Board (CPCB) 2009, during the study period. The 24 hourly average concentrations of sulphur dioxide (SO 2 ) and ammonia (NH 3 ) were within the permissible limits
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increases but unaffected at roundabouts with continuous traffic movement except at weekend days  although the emissions come from light duty vehicles (LDV), however, in U.K with large fleet of light duty diesel engines have made a significant reduction in both NO and smoke emissions since the transition from Euro III to Euro IV vehicles . Moreover engine loads and vehicle speed are closely linked to fuel consumption and pollutant emission rates  as well as driving conditions. An investigation of gasoline direct Injection engine (GDIE) particulate emissions rates in the real world driving conditions using standard driving cycles shows that the ratio of semi- volatile particles to total particle number is generally higher during acceleration followed by the idle operating mode. More particles per kilometre are produced during acceleration compared to cruise conditions . The use of Methyl- cyclopentadienyl Manganese Tricarbonyl (MMT) in GDIE as antiknock and to improve octane rating increases the total particulate mass (TPM) and number concentrations and increases CO and NOx emissions while HC decreases significantly with the increase of MMT content in the test fuels, although phased out in 2004 [63, 64]. Research on the effect of different alcohol fuel use on the performance, emission and combustion characteristics of a gasoline engine when compared with gasoline fuel showed that NOx, HC and CO emissions increased while CO 2 emissions
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Infrastructure includes three important elements; economic, environmental and social impact. Poor air quality affects the health of people. The negative effect must be reduced in order to have a better quality of life and good environment especially in public area. The aim of this study to examine the characteristics of air pollution in Penang, to determine the relationship between air pollutant and meteorological parameters and to determine the source contributions of air pollution in Penang using Factor analysis (FA). When the sources contribute to air pollution in Penang are known, a good preventive measure can be proposed to the responsible parties and this can help sustain the environment in Penang.
defined for specific pollutant types and vehicle types. The SCFs are used to take into account changes of emission factors for a particular road type. According to EPA (2001), SCFs of LDVs were estimated by emission tests of some LDVs under various driving cycles. A total of 12 driving cycles were used: six for the Freeway road type (average speeds of 63.2, 59.7, 52.7, 30.5, 18.6, 13.1 mile/h), one for freeway ramp (average speed of 34.6 mile/h), three for the Arterial road type (average speeds of 24.8, 19.2, and 11.6 mile/h), one for the Local road type (average speed of 12.9 mile/h) and one for the Non- freeway-Area-Wide-Urban-Travel (19.4 mile/h). Maximum speed and acceleration in each driving cycle are listed in Table C1 (Appendix C).In the case of HDVs, SCFs of NOx are described in a function of average speed (EPA, 2001). There are separate functions for Heavy Duty Diesel Vehicles (HDDVs) and Heavy Duty Gasoline Vehicles (HDGVs) as shown in Figure C1 (Appendix C). The SCF of HDDVs for NOx emissions has a U-Shape function where emissions are high in low and high average speeds, and emissions are lower at intermediate average speeds. On the other hand, SCFs of HDGV linearly increase with the average speed. Since emissions are different for different driving cycles for the same average speed, Mobile6.2 uses the Off-Cycle Correction Factors (OCCF) for NOx emissions of HDVs. OCCF are determined for each road type (EPA, 2002b).
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Ajav et al. (1999) presented an experimental study of some performance parameters of a constant speed stationary diesel engine using ethanol-diesel oil blends as fuel. Tests with 5 %, 10 %, 15 % and 20 % of ethanol were carried out. The lesser amount of carbon and the presence of oxygen in ethanol composition contributed to the reduction of carbon monoxide (CO) emission. The lower fuel/air ratio and the higher latent heat of vaporization of ethanol compared to diesel oil lead to lower flame temperature and reduced NO X emissions. The authors concluded that the diesel engine at constant speed can operate satisfactorily
Next, we discuss our results pertaining to petroleum emissions in China. In Figure 3, we can see that CP strategies were primarily responsible for reducing petro- leum discharges between 1998 and 2010. This is because the international price of oil increased rapidly after 1998 due to reductions in crude oil production in OPEC and non-OPEC countries. The oil price in China has been linked to the international price of oil since 1998. This oil price increase offered an incentive for manufacturing firms to reduce inputs of petroleum products in order to reduce production costs. Therefore, we attribute the ef- fects of CP programs on petroleum emissions to the in- fluence of the market, not to environmental policy. Meanwhile, EOP treatments also contributed to emis- sions reductions after 2000. PSC caused emissions to increase monotonically after 1998.
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A two dimensional advection-diffusion numerical model for air pollution in the presence of removal mechanisms and chemical reaction of primary and secondary pollutants due to area source in an urban area for stable and neutral conditions is presented in this paper. This model analysis gives that the ground level concentration of primary pollutants attains peak value at the downwind end of the city region and decreases rapidly to a constant value over the source free region. This is due to the fact that there is no emission beyond the city limit and hence the concentration decreases asymptotically to a constant value. The concentration of primary and secondary pollutants decreases as the removal mechanisms such as dry deposition and gravitational settling velocity increases for stable and neutral cases. The concentration of primary and secondary pollutants reaches more heights in neutral case when compared to the stable atmospheric condition. This indicates that neutral atmospheric condition enhances the vertical diffusion carrying the pollutants concentration to greater heights and thus the concentration is less at the surface region.
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higher than the US-EPA, WHO and NEQS-Pak limits for both urban and peri-urban areas. We concluded that both urban and peri-urban areas were highly polluted and posing potential threats to inhabitants. It is suggested that size segregated pollutant could be controlled by using environ- mental engineering techniques. Furthermore, complete restrict emissions related to transport- tations are required to control size segregated polluted. In peri-urban areas, paved roads should be constructed and brick kilns should be situated far away from outskirts areas to avoid minimal exposure. Urgent mitigation measures and strategy should be adopted to control the size segregated pollutant for better air quality in metropolitan Faisalabad and thus improving the air quality for ecosystems sustainability and mars the serenity of the real estate environment at large for habitation. Acknowledgement
Mokhtar et al., 2014), particulate matter (Kesarkar et al., 2007), and smelting of mercury from silver (Hagan et al., 2011). Also, Mokhtar et al. (2014) used Air dispersion modelling (AERMOD) to predict ground level concentration within 10 km radius of the emission source. Based on Health Risk Assessment, various health risks were identified for both short-term and long- term dispersion of the desired air pollutants. In addition, Markamdeya et al. (2016b) showed that modeling results suggested that Gas-Based Power Plants could be considered a clean substitute for coal power plants, located inside the city and polluting the environment considerably. The main objective of the current modeling study is to estimate the potentials of air emissions from Besat gas-based power plant along with maximum ground level concentration of nitrogen dioxide (NO 2 ), and determine its
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There are two types of CFD techniques: the diagnostic and prognostic. The diagnostic interpolation methods are based on measurements that are subject to physical constraints (Li et al., 2006). The prognostic uses three approaches the Reynolds-averaged Navier-Stokes theory, the direct numerical simulation, and the large eddy simulation. This type of dispersion model allows more detailed examination of vehicle-induced turbulence in areas with complex street canyon geometries (Pierce, 2004), (Huber, 2006) uses CFD to study human exposure factors and human exposure profiles dominated by local source emissions.
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