Simulation of ambient-air drying of rapeseed: II. Effects of fan-control strategies and type of weather data on drying parameter profiles

1988 ◽  
Vol 31 (2) ◽  
pp. 119-131
Author(s):  
B.G. Patil ◽  
G.T. Ward
Keyword(s):  
Control Strategies ◽  
Ambient Air ◽  
Weather Data ◽  
Air Drying

scholarly journals Effectiveness of SOx, NOx, and Primary Particulate Matter Control Strategies in the Improvement of Ambient PM Concentration in Taiwan

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 460
Author(s):  
Jiun-Horng Tsai ◽  
Ming-Ye Lee ◽  
Hung-Lung Chiang
Keyword(s):  
Particulate Matter ◽  
Air Quality ◽  
Model Simulation ◽  
Control Strategies ◽  
Ambient Air ◽  
Clean Air Act ◽  
Control Measures ◽  
Control Plan ◽  
Clean Air ◽  
Pm2.5 Concentration

The Community Multiscale Air Quality (CMAQ) measurement was employed for evaluating the effectiveness of fine particulate matter control strategies in Taiwan. There are three scenarios as follows: (I) the 2014 baseline year emission, (II) 2020 emissions reduced via the Clean Air Act (CAA), and (III) other emissions reduced stringently via the Clean Air Act. Based on the Taiwan Emission Data System (TEDs) 8.1, established in 2014, the emission of particulate matter 2.5 (PM2.5) was 73.5 thousand tons y−1, that of SOx was 121.3 thousand tons y−1, and that of NOx was 404.4 thousand tons y−1 in Taiwan. The CMAQ model simulation indicated that the PM2.5 concentration was 21.9 μg m−3. This could be underestimated by 24% in comparison with data from the ambient air quality monitoring stations of the Taiwan Environmental Protection Administration (TEPA). The results of the simulation of the PM2.5 concentration showed high PM2.5 concentrations in central and southwestern Taiwan, especially in Taichung and Kaohsiung. Compared to scenario I, the average annual concentrations of PM2.5 for scenario II and scenario III showed reductions of 20.1% and 28.8%, respectively. From the results derived from the simulation, it can be seen that control of NOx emissions may improve daily airborne PM2.5 concentrations in Taiwan significantly and control of directly emitted PM2.5 emissions may improve airborne PM2.5 concentrations each month. Nevertheless, the results reveal that the preliminary control plan could not achievethe air quality standard. Therefore, the efficacy and effectiveness of the control measures must be considered to better reduce emissions in the future.

scholarly journals Ozone response to emission changes: a modeling study during the MCMA-2006/MILAGRO campaign

2009 ◽  
Vol 9 (6) ◽  
pp. 23419-23463 ◽  
Author(s):  
J. Song ◽  
W. Lei ◽  
N. Bei ◽  
M. Zavala ◽  
B. de Foy ◽  
...  
Keyword(s):  
Control Strategies ◽  
Monitoring Network ◽  
Ambient Air ◽  
Ozone Production ◽  
Daily Maximum ◽  
Chemical Production ◽  
Field Campaign ◽  
Ozone Concentrations ◽  
Urban Core ◽  
Emission Changes

Abstract. The sensitivity of ozone production to precursor emissions was investigated under five different meteorological conditions in the Mexico City Metropolitan Area (MCMA) during the MCMA-2006/MILAGRO field campaign using the gridded photochemical model CAMx driven by observation-nudged WRF meteorology. Precursor emissions were constrained by the comprehensive data from the field campaign and the routine ambient air quality monitoring network. Simulated plume mixing and transport were examined by comparing with measurements from the G-1 aircraft during the campaign. The observed concentrations of ozone precursors and ozone were well reproduced by the model. The effects of reducing precursor emissions on urban ozone production were performed for three representative emission control strategies. A 50% reduction in VOC emissions led to 7 to 22 ppb decrease in daily maximum ozone concentrations, while a 50% reduction in NOx emissions leads to 4 to 21 ppb increase, and 50% reductions in both NOx and VOC emission decrease the daily maximum ozone concentrations up to 10 ppb. These results along with a chemical indicator analysis using the chemical production ratios of H2O2 to HNO3 demonstrate that the MCMA urban core region is VOC-limited for all meteorological episodes, which is consistent with the results from MCMA-2003 field campaign; however the degree of the VOC-sensitivity is higher in the MCMA-2006 due to lower VOC/NOx emission ratio and VOC reactivity. Ozone formation in the surrounding mountain/rural area is mostly NOx-limited, but can be VOC-limited, and the range of the NOx-limited or VOC-limited areas depends on meteorology.

FlyBoss: a web-based flystrike information and decision support system

2010 ◽  
Vol 50 (12) ◽  
pp. 1069 ◽  
Author(s):  
B. Horton ◽  
L. Hogan
Keyword(s):  
Best Practice ◽  
Control Strategies ◽  
Present Report ◽  
Decision Aids ◽  
Simulation Models ◽  
Weather Data ◽  
Economic Management ◽  
Control Programs ◽  
Comprehensive Information ◽  
Control And Prevention

The FlyBoss system consists of comprehensive information on flystrike management and control, programs for assisting decision making, and sortable lists of products for preventing and treating flystrike. Readily accessible, up-to-date, best-practice information on flystrike is essential for effective, humane and economic management of flystrike by Australian wool producers, particularly those who are phasing out mulesing and those looking to adopt optimal insecticidal fly-control strategies. FlyBoss provides information on breeding and management to reduce flystrike susceptibility, effective methods of treating existing flystrike and flystrike prevention programs. The FlyBoss decision aids, which are based on simulation models and incorporate local weather data and sheep susceptibility factors, can assist sheep farmers who wish to optimise sheep management, chemical treatment and non-chemical options to minimise the risk of flystrike. FlyBoss also contains comprehensive information on fly biology, sheep and environmental factors associated with flystrike and information on appropriate chemicals for various situations. FlyBoss draws on expertise from organisations throughout Australia to provide the sheep industry with easily accessible, current and locally targeted information on flystrike management. The present report briefly describes the development of FlyBoss and associated workshops and provides an overview of current recommendations for the control and prevention of flystrike.

Ochratoxin A production during ambient-air drying

2014 ◽  
Vol 56 ◽  
pp. 1-7 ◽  
Author(s):  
T.J. Wontner-Smith ◽  
D.M. Bruce ◽  
S.K. Cardwell ◽  
D.M. Armitage ◽  
P. Jennings
Keyword(s):  
Ochratoxin A ◽  
Ambient Air ◽  
Air Drying

Inlet Air Supercharging of a 70 kW Microturbine

2006 ◽  
Author(s):  
Robert Brandon ◽  
Bryan Halliday ◽  
John S. Hoffman
Keyword(s):  
Air Temperature ◽  
Gas Turbines ◽  
Ambient Air ◽  
Business Case ◽  
Weather Data ◽  
Limiting Factor ◽  
Boost Pressure ◽  
Ambient Temperatures ◽  
Ambient Air Temperature ◽  
Field Deployment

The significant reduction in power output of small gas turbines at high ambient temperatures places the technology at a significant disadvantage compared with reciprocating engines. On site power applications in many jurisdictions are experiencing high power costs during summer peak times. A variable speed industrial fan combined with an evaporative cooler has been constructed and operated in the CETC laboratory in Ottawa, Canada to supply supercharged inlet air to a microturbine rated at 70 kW at ISO conditions. The supercharging system can raise the inlet air pressure by 10.5 kPa (42” wc). A mapping of the turbine performance has been done as a function of boost pressure, relative humidity and ambient air temperature. A net power increase has been observed from 57 kW to 70 kW at an ambient air temperature of 33°C (91°F) and RH of 60%, a 23% increase. Supercharging at lower temperatures yields lower net power increases since the microturbine generator rating is the limiting factor; for example an 11% increase in net power was observed at an inlet air temperature of 11°C (52°F) and RH of 60%. Supercharging was shown to decrease net fuel-to-electricity efficiency of this recuperated turbine by about 3%, at an air temperature of 33°C (91°F). An economic analysis using published power prices and weather data from Toronto explores the business case of using supercharging, with the best economies likely for multiple units or larger microturbines, such as 250 kW units. The objective of the project was to demonstrate the concept leading to a field trial in Toronto or in Calgary where the altitude offers a further benefit to the inlet air supercharging concept. Work is underway to design a control system suitable for field deployment for the concept.

scholarly journals Feasibility and difficulties of China's new air quality standard compliance: PRD case of PM<sub>2.5</sub> and ozone from 2010 to 2025

2013 ◽  
Vol 13 (23) ◽  
pp. 12013-12027 ◽  
Author(s):  
H. Liu ◽  
X. M. Wang ◽  
J. M. Pang ◽  
K. B. He
Keyword(s):  
Air Quality ◽  
Control Strategies ◽  
Nox Reduction ◽  
Ambient Air ◽  
Quality Standard ◽  
Average Concentration ◽  
Air Pollutant ◽  
Control Measures ◽  
Ozone Pollution ◽  
Pm2.5 And Pm10

Abstract. Improving the air quality in China is a long and arduous task. Although China has made very aggressive plans for air pollutant control, the difficulties in achieving the new air quality goals are still significant. A lot of cities are developing their implementation plan (CIP) for new air quality goals. In this study, a southern city, Guangzhou, has been selected to analyze the feasibility and difficulties of new air quality standard compliance, as well as the CIP evaluation. A comprehensive study of the air quality status in Guangzhou and the surrounding area was conducted using 22 monitoring sites collection data for O3, PM2.5 and PM10. The monthly non-attainment rates for O3 vary from 7 to 25% for May to November. The city average PM2.5 concentration was 53 μg m−3 in Guangzhou in 2010, which needs to be reduced by at least 34% to achieve the target of 35 μg m−3. The PM2.5 high violation months are from November to March. A CIP was developed for Guangzhou, which focused on PM2.5. Based on the CIP, the emission amounts of NOx, PM10, PM2.5 and volatile organic compounds (VOCs) in 2025 would be controlled to 119, 61, 26 and 163 thousand tons, respectively, reduced by 51.9%, 55.9%, 61.8% and 41.3%, respectively, compared to 2010. Analysis of air quality using the model MM5-STEM suggests that the long-term control measures would achieve the PM2.5 and PM10 goals successfully by 2025. The PM2.5 annual average concentration would be reduced to 27 μg m−3 in 2025. However, such PM2.5-based emission control scenarios may enhance the ozone pollution problems. The O3 non-attainment rate would increase from 7.1% in 2010 to 12.9% in 2025, implying that ozone will likely become a major compliance issue with the new national ambient air quality standards (NAAQS). This suggests that O3 control must be taken into account while designing PM2.5 control strategies, especially PM2.5 compliance under increased atmospheric oxidation, and for VOCs / NOx reduction ratios need to be further investigated, in order to eventually achieve O3–PM2.5 co-improvement in this region or other cities.

scholarly journals An Energy Balance Model for Predicting Berry Temperature and Scheduling Sprinklers for Cooling in Northern Highbush Blueberry

HortScience ◽  
2021 ◽  
pp. 1-7
Author(s):  
Fan-Hsuan Yang ◽  
David R. Bryla ◽  
R. Troy Peters
Keyword(s):  
Fruit Size ◽  
Weather Forecast ◽  
Ambient Air ◽  
Vaccinium Corymbosum ◽  
Weather Data ◽  
Balance Model ◽  
Highbush Blueberry ◽  
Cooling Efficiency ◽  
Water Users ◽  
Northern Highbush Blueberry

Heat-related fruit damage is a prevalent issue in northern highbush blueberry (Vaccinium corymbosum L.) in various growing regions, including the northwestern United States. To help address the issue, we developed a simple climatological model to predict blueberry fruit temperatures based on local weather data and to simulate the effects of using over-canopy sprinklers for cooling the fruit. Predictions of fruit temperature on sunny days correlated strongly with the actual values (R2 = 0.91) and had a root mean-square error of ≈2 °C. Among the parameters tested, ambient air temperature and light intensity had the greatest impact on fruit temperature, whereas wind speed and fruit size had less impact, and relative humidity had no impact. Cooling efficiency was estimated successfully under different sprinkler cooling intervals by incorporating a water application factor that was calculated based on the amount of water applied and the time required for water to evaporate from the fruit surface between the intervals. The results indicate that water temperature and nozzle flow rate affected the extent to which cooling with sprinklers reduced fruit temperature. However, prolonging the runtime of the sprinklers did not guarantee lower temperatures during cooling, because cooling efficiency declined as the temperature of the fruit approached the temperature of the irrigation water. Users could incorporate the model into weather forecast programs to predict the incidence of heat damage and could use it to make cooling decisions in commercial blueberry fields.

Assessing Emissions Contribution of Intercity Trucking

1996 ◽  
Vol 1520 (1) ◽  
pp. 35-43
Author(s):  
Sergio J. Ostria
Keyword(s):  
Air Quality ◽  
Factor Model ◽  
Control Strategies ◽  
Ambient Air ◽  
Control Measures ◽  
Planning Processes ◽  
Emissions Inventories ◽  
Truck Transport ◽  
Drayage Operations ◽  
Implementation Plans

The contribution of intercity trucking to air pollution in a given region is readily recognized as significant by transportation and air quality planners. Other than emissions standards for newly sold trucks, neither the air quality nor the transportation planning communities has focused on implementing control strategies that directly mitigate emissions from intercity trucking. As nonattainment areas strive to comply with the National Ambient Air Quality Standards, the potential emission reduction benefits of truck-related control measures must be evaluated to ensure that all sources of emissions are considered in the planning processes. However, little is known about the contribution of intercity trucking to emissions inventories in regions across the country, particularly since the Environmental Protection Agency's MOBILE emissions factor model is not well-suited for this purpose. The incorporation of intercity trucking in emission inventory estimates is reviewed, and a methodology by which intercity trucking emissions can be easily isolated using information documented in state implementation plans (SIPs) is developed. Using SIP data for a select number of metropolitan areas and the Truck Inventory and Use Survey (TIUS), the emissions contributions of city-to-city truck transport and drayage operations are assessed. Furthermore, the contribution of intercity trucking to emission reductions in areas across the country is determined using information reported in 15 percent volatile organic compound reduction plans.

Urea-SCR system development in the mitigation of NOx emissions from diesel engines – A review study

2020 ◽  
Vol 09 ◽  
Author(s):  
Mina Mehregan
Keyword(s):  
Nitrogen Oxides ◽  
Diesel Engines ◽  
Energy Demand ◽  
Catalytic Reduction ◽  
Control Strategies ◽  
Ambient Air ◽  
Short Review ◽  
Injection System ◽  
Forest Damage ◽  
Nox Emissions

Introduction: Due to energy demand concerns, diesel engines have gained much attraction recently compared to petrol engines because of their higher thermal efficiencies. However, they emit larger amount of NOx emissions into the atmosphere. Nitrogen oxides are known as important ambient air pollutants which are responsible for health problems, forest damage and buildings corrosion. Therefore, using emissions control strategies for diesel engines are required in order to have a cleaner environment. Urea-SCR (selective catalytic reduction of NOx by urea) after-treatment system is considered as one of the most efficient techniques available to reduce engine-out NOx emissions sufficiently. Conclusion: This review article discusses a short review on all the methods suggested to diminish nitrogen oxides emissions and then presents a comprehensive survey on developing urea-SCR unit -whether from catalyst development aspect or from injection system modification point of view- in diesel engines to meet strict emissions regulations.

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