scholarly journals High efficiency of livestock ammonia emission controls in alleviating particulate nitrate during a severe winter haze episode in northern China

2019 ◽  
Vol 19 (8) ◽  
pp. 5605-5613 ◽  
Author(s):  
Zhenying Xu ◽  
Mingxu Liu ◽  
Minsi Zhang ◽  
Yu Song ◽  
Shuxiao Wang ◽  
...  
Keyword(s):  
High Efficiency ◽  
Northern China ◽  
Forecast Model ◽  
Ammonia Emission ◽  
Severe Winter ◽  
Nh3 Emission ◽  
Emission Controls ◽  
High Pollution ◽  
Haze Episode ◽  
Thermodynamic Equilibrium Model

Abstract. Although nitrogen oxide (NOx) emission controls have been implemented for several years, northern China is still facing high particulate nitrate (NO3-) pollution during severe haze events in winter. In this study, the thermodynamic equilibrium model (ISORROPIA-II) and the Weather Research and Forecast model coupled with chemistry (WRF-Chem) were used to study the efficiency of NH3 emission controls on alleviating particulate NO3- during a severe winter haze episode. We found that particulate-NO3- formation is almost NH3-limited in extremely high pollution but HNO3-limited on the other days. The improvements in manure management of livestock husbandry could reduce 40 % of total NH3 emissions (currently 100 kt month−1) in northern China in winter. Consequently, particulate NO3- was reduced by approximately 40 % (on average from 40.8 to 25.7 µg m−3). Our results indicate that reducing livestock NH3 emissions would be highly effective in reducing particulate NO3- during severe winter haze events.

scholarly journals High efficiency of livestock ammonia emission controls on alleviating particulate nitrate during a severe winter haze episode in northern China

2018 ◽  
Author(s):  
Zhenying Xu ◽  
Mingxu Liu ◽  
Yu Song ◽  
Shuxiao Wang ◽  
Lin Zhang ◽  
...  
Keyword(s):  
High Efficiency ◽  
Northern China ◽  
Forecast Model ◽  
Ammonia Emission ◽  
Manure Management ◽  
Severe Winter ◽  
Nh3 Emission ◽  
Emission Controls ◽  
Haze Episode ◽  
Thermodynamic Equilibrium Model

Abstract. Although nitrogen oxide (NOx) emission controls have been implemented for several years in northern China, recent observations show particulate nitrate (NO3−) is becoming increasingly important during haze episodes. In this study, we find that particulate NO3− formation would easily become NH3-limited under severe haze conditions, enhancing its sensitivity to NH3 emission controls. Furthermore, improved manure management of livestock husbandry could reduce 40 % of NH3 emissions (currently 100 kiloton per a month) in winter of northern China. Under this emission reductions scenario, simulations from the thermodynamic equilibrium model (ISORROPIA-II) and the Weather Research and Forecast model coupled chemistry (WRF-Chem) all show that particulate NO3− could be reduced by approximately 40 % during a typical severe haze episode (averagely from 40.8 to 25.7 μg/m3). Our results indicate that reducing livestock NH3 emissions would be highly effective to reduce particulate NO3− during severe winter haze events.

scholarly journals Major Elements to Consider in Developing Ammonia Emission Factor at Municipal Solid Waste (MSW) Incinerators

2021 ◽  
Vol 13 (4) ◽  
pp. 2197
Author(s):  
Seongmin Kang ◽  
Joonyoung Roh ◽  
Eui-chan Jeon
Keyword(s):  
Municipal Solid Waste ◽  
Solid Waste ◽  
Emission Factor ◽  
Waste Incineration ◽  
Emission Factors ◽  
Major Elements ◽  
Ammonia Emission ◽  
Nh3 Emission ◽  
The Difference ◽  
The One

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.

scholarly journals Ammonia emissions from a naturally and a mechanically ventilated broiler house in Brazil

2014 ◽  
Vol 18 (11) ◽  
pp. 1179-1185 ◽  
Author(s):  
Luciano B. Mendes ◽  
Ilda F. F. Tinoco ◽  
Nico W. M. Ogink ◽  
Keller S. O. Rocha ◽  
Jairo A. Osorio S. ◽  
...  
Keyword(s):  
Ventilation System ◽  
Stocking Density ◽  
Emission Factors ◽  
Ammonia Emission ◽  
Mechanically Ventilated ◽  
Nh3 Emission ◽  
Modeling Process ◽  
Tropical Conditions ◽  
Ventilation Rates ◽  
Broiler House

This study was conducted with the aim of monitoring NH3 emissions from a mechanically and a naturally ventilated broiler house (MVB and NVB, respectively) and calculate their ammonia emission factors (fNH3). Bird stocking density was 13.5 and 11.1 birds m-2 for the MVB and NVB, respectively. The marketing age was 43 days and bedding consisted of dried coffee husks in its first time of use. Ventilation rates were calculated with the metabolic carbon dioxide mass balance method. Values of fNH3 were 0.32 ± 0.10 and 0.27 ± 0.07 g bird-1 d-1 for the MVB and NVB, respectively, and are in agreement to what was presented in other studies performed under similar conditions. The fNH3 estimated on yearly basis was 58 g bird-place-1 year-1. It was concluded that the different types of ventilation system between the studied broiler barns did not significantly affect emissions in the modeling process. The results obtained help providing reliable methodology for the determination of a solid database on NH3 emission factors for tropical conditions that can be used for future inventories, when performed in a sufficient number of barns that is representative for the Brazilian scenario.

How grass contributes to controlling hillslope erosion

2020 ◽  
Author(s):  
Chengzhong Pan ◽  
Lan Ma
Keyword(s):  
Spatial Distribution ◽  
Soil Erosion ◽  
High Efficiency ◽  
Northern China ◽  
Bare Soil ◽  
Soil Characteristics ◽  
Vegetation Coverage ◽  
Grass Cover ◽  
Run Off ◽  
Set Up

<p>The aim of this study was to investigate how the spatial distribution of grass influenced run-off and erosion from a hillslope with loess and cinnamon soils in the rocky area of Northern China. We set up a trial to test the two soils with different treatments, including bare soil (BS), grass strips on the upper (UGS) and lower (DGS) parts of the slope, grass cover over the entire slope (GS), and a grass carpet on the lower part of the slope (GC), under simulated rainfall conditions. The results showed that the run-off coefficients for the loess and cinnamon soils decreased by between 4% and 20% and by between 2% and 37%, respectively, when covered with grass. Grass spatial distribution had little effect on the run-off, but more effect on erosion than vegetation coverage degree. The most effective location of grass cover for decreasing hillslope erosion was at the foot, and the high efficiency was mainly due to controlling of rill formation and sediment deposition. The soil loss from GS, DGS, and GC on the loess and cinnamon soils was between 77% and 93% less and 55% and 80% less, respectively, compared with the loss from BS. However, the soil characteristics had little effect on soil erosion for well-vegetated slopes. The results highlight the importance of vegetation re-establishment at the foot of hillslope in controlling soil erosion.</p>

scholarly journals Ammonia emission from dairy cow buildings: a review of measurement techniques, influencing factors and possibilities for reduction

1998 ◽  
pp. 225-247 ◽  
Author(s):  
G.J. Monteny ◽  
J.W. Erisman
Keyword(s):  
Dairy Cow ◽  
Measurement Techniques ◽  
Ammonia Emission ◽  
Feeding Strategies ◽  
Housing Type ◽  
Emission Data ◽  
Single Measure ◽  
Housing Systems ◽  
Nh3 Emission ◽  
Good Potential

This study aimed to make an analytical inventory of ammonia emission data of dairy housing systems and to assess possibilities for reduction, based upon the analysis of processes and factors involved in the production and volatilization of ammonia. Mass balance methods for the determination of air exchange rates for naturally ventilated dairy cow buildings that are based upon natural or introduced tracers may have good potential for application in emission studies. Differences occur in housing systems, floor types and manure collection and manure storage systems. Ammonia emission levels for cubicle (loose) houses are higher (20-45 g/day/cow) than for tie stalls (5-27 g/day/cow), and variation in emissions by housing type is large. Integration of knowledge of ammonia emission related processes and factors will support a more detailed analysis of differences and variation, and will allow optimization of possibilities for emission reduction. Substantial emission reductions of up to 50% for cubicle houses with slatted floors can be achieved through each of the following measures: flushing of floors with water or diluted formaldehyde, optimised feeding strategies, and slurry acidification. Highest reductions are possible through V-shaped, solid floors (52%) as a single measure, or in combination with flushing with water (65%) or diluted formaldehyde (80%). Providing that drawbacks are solved, nationwide introduction of one or more these measures will lead to a maximal reduction of the NH3 emission in the Netherlands to 18 kt per year.

scholarly journals Improved gridded ammonia emission inventory in China

2021 ◽  
Author(s):  
Baojie Li ◽  
Lei Chen ◽  
Weishou Shen ◽  
Jianbing Jin ◽  
Teng Wang ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Emission Inventory ◽  
Mainland China ◽  
Fertilizer Application ◽  
Mitigation Strategies ◽  
Ammonia Emission ◽  
Emission Inventories ◽  
Livestock Waste ◽  
Nh3 Emission ◽  
Spatial Differences

Abstract. As a major alkaline gas in the atmosphere, NH3 significantly impacts atmospheric chemistry, ecological environment, and biodiversity. Gridded NH3 emission inventories can significantly affect the accuracy of model concentrations and play a crucial role in the refinement of mitigation strategies. However, several uncertainties are still associated with existing NH3 emission inventories in China. Therefore, in this study, we focused on improving fertilizer application-related NH3 emission inventories. We comprehensively evaluated the dates and times of fertilizer application to the major crops that are cultivated in China, improved the spatial allocation methods for NH3 emissions from croplands with different rice types, and established a gridded NH3 emission inventory for mainland China with a resolution of 5 min × 5 min in 2016. The results showed that the atmospheric NH3 emissions in mainland China amounted to 12.11 Tg, with livestock waste (44.8 %) and fertilizer application (38.6 %) being the two main NH3 emission sources in China. Obvious spatial differences in NH3 emissions were also observed, and high emissions were predominantly concentrated in North China. Further, NH3 emissions tended to be high in summer and low in winter, and the ratio for the July–January period was 3.08. Furthermore, maize and rice fertilization in summer was primarily responsible for the increase in NH3 emissions in China, and the evaluation of the spatial and temporal accuracy of the NH3 emission inventory established in this study using the WRF-Chem and ground station- and satellite-based observations showed that it was more accurate than other inventories.

scholarly journals Thallus sectioning as an efficient monospore release method in Pyropia yezoensis (Bangiales, Rhodophyta)

2019 ◽  
Vol 32 (4) ◽  
pp. 2195-2200 ◽  
Author(s):  
Nianci Chen ◽  
Lei Tang ◽  
Xiaowei Guan ◽  
Rui Chen ◽  
Min Cao ◽  
...  
Keyword(s):  
High Efficiency ◽  
Low Cost ◽  
Economic Value ◽  
Northern China ◽  
Pyropia Yezoensis ◽  
Effect Of Temperature ◽  
Seeding Strategy ◽  
Increasing Demand ◽  
Short Time ◽  
Release Method

AbstractThe red seaweed Pyropia yezoensis is a marine crop of important economic value and is widely cultivated in the coastal areas of northern China. The current seedling-raising system relies on the germination of conchospores, a process not fast enough to meet the increasing demand from farmers. In this study, we developed a monospore-dependent seedling method based on the asexual reproduction of the Pyropia thallus. The Pyropia thallus was physically sectioned into small pieces (microthalli) that were cultivated at 15 °C. The algal cells in the microthalli became morphologically condensed, underwent cell division, and then developed into monospores on the 5th day. The monospores were able to attach to the seeding rope in 24 h and germinated into healthy thalli. To optimize the efficiency of monospore release, we tested the effect of temperature and the size and original positions of the microthalli as well as the age of the mother thallus. Microthalli with a size of 30–50 cells from the middle and apex of 21-day-old thalli cultivated at 15 °C yielded the optimum production of monospores. Theoretically, in this thallus-to-thallus seeding strategy, 0.1 g of thallus could produce at least 107 monospores, with the same number of offspring thallus seedlings. Taking all of these advantages together, including the high efficiency, short time, low cost and easy operation, this physical sectioning method could serve as a promising seed source especially for new cultivars with superior traits in Pyropia farming and rapid replenishment of seedlings when thalli undergo disastrous diseases.

scholarly journals Influence of aerosols and surface reflectance on satellite NO<sub>2</sub> retrieval: seasonal and spatial characteristics and implications for NO<sub><i>x</i></sub> emission constraints

2015 ◽  
Vol 15 (19) ◽  
pp. 11217-11241 ◽  
Author(s):  
J.-T. Lin ◽  
M.-Y. Liu ◽  
J.-Y. Xin ◽  
K. F. Boersma ◽  
R. Spurr ◽  
...  
Keyword(s):  
Optical Properties ◽  
Eastern China ◽  
Northern China ◽  
Sampling Bias ◽  
Western China ◽  
Surface Reflectance ◽  
Retrieval Process ◽  
Ozone Monitoring Instrument ◽  
Vertical Column ◽  
High Pollution

Abstract. Satellite retrievals of vertical column densities (VCDs) of tropospheric nitrogen dioxide (NO2) normally do not explicitly account for aerosol optical effects and surface reflectance anisotropy that vary with space and time. Here, we conduct an improved retrieval of NO2 VCDs over China, called the POMINO algorithm, based on measurements from the Ozone Monitoring Instrument (OMI), and we test the importance of a number of aerosol and surface reflectance treatments in this algorithm. POMINO uses a parallelized LIDORT-driven AMFv6 package to derive tropospheric air mass factors via pixel-specific radiative transfer calculations with no look-up tables, taking slant column densities from DOMINO v2. Prerequisite cloud optical properties are derived from a dedicated cloud retrieval process that is fully consistent with the main NO2 retrieval. Aerosol optical properties are taken from GEOS-Chem simulations constrained by MODIS aerosol optical depth (AOD) data. MODIS bi-directional reflectance distribution function (BRDF) data are used for surface reflectance over land. For the present analysis, POMINO level-2 data for 2012 are aggregated into monthly means on a 0.25° long. × 0.25° lat. grid. POMINO-retrieved annual mean NO2 VCDs vary from 15–25 × 1015 cm−2 over the polluted North China Plain (NCP) to below 1015 cm−2 over much of western China. Using POMINO to infer Chinese emissions of nitrogen oxides leads to annual anthropogenic emissions of 9.05 TgN yr−1, an increase from 2006 (Lin, 2012) by about 19 %. Replacing the MODIS BRDF data with the OMLER v1 monthly climatological albedo data affects NO2 VCDs by up to 40 % for certain locations and seasons. The effect on constrained NOx emissions is small. Excluding aerosol information from the retrieval process (this is the traditional "implicit" treatment) enhances annual mean NO2 VCDs by 15–40 % over much of eastern China. Seasonally, NO2 VCDs are reduced by 10–20 % over parts of the NCP in spring and over northern China in winter, despite the general enhancements in summer and fall. The effect on subsequently constrained annual emissions is between −5 and +30 % with large seasonal and spatial dependence. The implicit aerosol treatment also tends to exclude days with high pollution, since aerosols are interpreted as effective clouds and the respective OMI pixels are often excluded by cloud screening; this is a potentially important sampling bias. Therefore an explicit treatment of aerosols is important for space-based NO2 retrievals and emission constraints. A comprehensive independent measurement network with sufficient spatial and temporal representativeness is needed to further evaluate the different satellite retrieval approaches.

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