Assessment of the Energy Conversion on the Thermal Balance and Atmospheric Emissions in Ceramic Tile Product Industry in Tunisia: A Case Study

This work aims to assess the effect of energy conversion (Thermal oil, Natural gas and cogeneration system) on atmospheric emission and energy consumption in ceramic tile product sector in Tunisia. Two tile manufactures were selected. The first plant has two production lines: The first line (FF1) operates with thermal oil with a lower calorific value (LHV) of 9811 cal/g and the second line (FG1) operating with natural gas has a lower calorific value (HHV) of 10,520 cal/g, ensuring a daily output of 300 tons each one. The second manufacture (SC2) operates with natural gas with the same LHV value. The thermal oil energy balance showed a specific consumption of 0.0481 toe/ton tile product for the FF1 manufacture line, 0.0198 toe/ton of tile product for the FG1 manufacture line and 0.0143 toe/ton of tile product for the SC2 manufactory. The electrical energy consumption was 0.0121 toe/ton of tile product for the FF1 line, 0.0108 toe/ton of tile product for the FG1 line and a production of energy (exergy) of 0.014 toe/ton for the SC2 production line. The specific consumption was split into 40% for dryer and 60% for tunnel kilns. The conversion allow to record a dryer reduction rate of 80% for nitrogen oxides (NOx), 56% for sulfur oxides (SOx), 56% for fluorinated compounds, 52% for chlorinated compounds and 52% for volatile organic compound. Whereas, the kiln reduction rate was 36% for nitrogen oxides, 51% for sulfur oxides, 36% for chlorinated compounds and 55% for fluorinated and 50% for volatile organic compounds (VCOs). Compared to natural gas line, the use of cogeneration system in kiln process shows a decrease of 67% for NOx emissions, 80% for SOx emissions, 89% for fluorinated compounds, 58% for chlorinated emissions and 64% for volatiles organic compounds. Compared to thermal oil, the use of cogeneration system reduces the thermal energy consumption by 70% and allowed to save 30% of electric energy by generate 20% of needed electric energy. The specific atmospheric gaseous emission level decrease from 2.066 g/kg of tile product for the thermal oil process to reach 0.43 g/kg of tile product for cogeneration process.

Atmospheric Emission Sources in the Po-Basin from the LIFE-IP PREPAIR Project

This paper presents the focus on emission estimates in the Italian Regions of the Po-basin obtained by the development of a common air pollutant emission dataset on the Po-basin and Slovenia foreseen in the project LIFE PREPAIR (https://www.lifeprepair.eu/). The objective is to update emission inventories developed by the environmental protection agencies and regions of Lombardy, Emilia-Romagna, Piedmont, Veneto, Friuli Venezia Giulia, Valle d’Aosta, the province of Bolzano (participating as stakeholder) and the province of Trento. A data flux is defined considering the activities on emission estimates by the different administrations according to the current Italian legislation. This activity has allowed the completion of two different datasets on the area for 2013 and 2017. The estimates of primary emissions of the main atmospheric pollutants have a high spatial resolution defined at the municipal level. The non-industrial combustion of biomass in small domestic appliances is the main source of primary PM10 in the Po-basin. NOx primary emissions are determined for quite of a half by road transport. Manure management and fertilization in the agriculture sector are the sources of NH3. The ensemble of the collected data shows a very good comparability even if all local compilers perform independently the estimates, thanks to a good alignment in using reference methodologies and to projects of common methodological development, as reported by the INEMAR project (https://www.inemar.eu/). The estimates of PM10, NOx and NH3 are comparable with data reported by the European Environment Agency EEA for the European Member States EU-28 (until 1 February 2020) and for Italy, reported under the UNECE Convention on Long-range Transboundary Air Pollution and European Union National Emission Ceiling Directive.

Estimates and Spatial Distribution of Emissions from Sugar Cane Bagasse Fired Thermal Power Plants in Brazil

Sugar cane bagasse is one of the largest fuels used for electricity generation in Brazil and its usage has continuously increased to supply the energy demand. This paper presents emission inventory based on power plants burning sugar cane bagasse. The inventory involves the spatial distribution and the estimated flows for the following major pollutants: nitrogen oxides (NOx), particulate material (PM), carbon dioxide (CO2) and total organic carbon (TOC). A total of 384 power plants were inventoried, representing a generated power of 9.9 GW, about 26% of the energy produced by thermal power plants sector. The plants are concentrated in two main poles: one of them in S?o Paulo State and nearby areas and the other one in coast of Brazilian Northeast. The limits proposed by the AP-42 Regulations of the US Environmental Protection Agency (USEPA) for the emission factors were applied. Additional emission factors identified in the scientific literature were also included in the analysis in order to assess the uncertainties associated to the estimative. The estimated emissions showed values in the range 16.0 - 20.5 Gg?year?1 for NOx, 18.0 - 267.0 Gg?year?1 for MP and 20.5 - 26.7 Tg?year?1 for CO2. The contribution of TOC showed a minor contribution around 10 - 20 Mg?year?1. PM showed to be the most representative pollutant emitted by the thermal plants burning sugar cane bagasse, but with a large range of uncertainty. There is a high level of uncertainty associated to the preparation of cane as well as the use of collectors to control particulate emissions. The adequate control over all stages could reduce the bagasse ash content in 90% or more.

Linking atmospheric emission and deposition to accumulation of soil cadmium in the Middle-Lower Yangtze Plain,China

Cadmium(Cd)is one of the most toxic heavy metals in the environment.Atmospheric deposition has been found to be the main source of Cd pollution of soil on a large scale in China,and identification of the relationships between anthropogenic emission,atmospheric deposition,and Cd accumulation in soil is important for developing ways to mitigate Cd non-point pollution.In this study,the relationship between atmospheric emission,atmospheric deposition,and soil Cd accumulation in the Middle-Lower Yangtze Plain in China was investigated using datasets of atmospheric emission,deposition,and soil accumulation from the literatures published between 2000 and 2020.The results showed that the soil Cd accumulation rate in the study area exceeded the national average(4.0μg kg^(–1)yr^(–1))and continued to accumulate in recent decades,although the average accumulation rate decreased from 9.45μg kg^(–1)yr^(–1)(2000–2010 period)to8.86μg kg^(–1)yr^(–1)(2010–2020 period).The contribution of atmospheric deposition flux to Cd increment in the soil was in the range of 22–29%,with the atmospheric deposition flux decreasing from 0.54 mg m^(–2)yr^(–1)(2000–2010)to 0.48 mg m^(–2)yr^(–1)(2010–2020),both values being greater than the national average.Atmospheric Cd deposition and emission were highly correlated in a provincial administrative region,which is close to a ratio of 1.0.Emission factors may be in a state of dynamic change due to the influences of new Cd emission control technologies and environmental policies.As the main sources of Cd emissions,dust,and smoke emissions per ton of non-ferrous metal production decreased by 64.7%between the 2000–2010 and 2010–2020 periods.Although new environmental policies have been instigated,atmospheric emission of Cd is still excessive.It was hoped that the findings of this work would provide a scientific basis for the rational control of atmospheric emissions and Cd pollution of soil.

The dawn−dusk asymmetry in mesosphere and lower thermosphere temperature disturbances during geomagnetic storms at high latitude

Utilizing observations by the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)instrument,we quantitatively assessed the dawn-dusk asymmetry in temperature disturbances within the high-latitude mesosphere and lower thermosphere(MLT)during the main phase of geomagnetic storms in this study.An analysis of five geomagnetic superstorm events indicated that during the main phase,negative temperature disturbances were more prevalent on the dawn side than on the dusk side in the high-latitude MLT region.Results of a statistical analysis of 54 geomagnetic storm events also revealed a notable disparity in temperature disturbances between the dawn and dusk sides.At high latitudes,38.2%of the observational points on the dawn side exhibited negative temperature disturbances(less than−5 K),whereas on the dusk side,this percentage was only 29.5%.In contrast,at mid-latitudes,these proportions were 34.1%and 36.5%,respectively,showing no significant difference.We also conducted a statistical analysis of temperature disturbances at different altitudes,which revealed an increase in the proportion of warming disturbances with altitude.Conversely,the proportion of cooling disturbances initially rose with altitude,reaching a peak around 105 km,and subsequently decreased.These temperature disturbance differences could be explained by the day-night asymmetry in vertical wind disturbances during storm conditions.

How Do Power Enterprises Deal with Total Quantity Control

This paper describes the relation and difference of "emission up to standards" and "total quantity control" ofmain atmospheric pollutants, as well as their legal status. It points out that the total quantity control is a good approachto solve a problem that environmental quality do not yet reach the requirements in an area where emission concentrationhas came up to standards, or to solve a problem that the interregional transportation of pollutants (e. g. acid rain) arises.And further, it put forward five proposals for the total quantity control.[

Olkaria Geothermal Power Plants, Kenya： Preliminary Evaluation of Mercury Emission to the Atmosphere

At Olkaria （Kenya） geothermal energy has been used since 1981, to generate electricity and now there are currently 3 plants with a nominal capacity of 205 MW. Preliminary measurement and evaluation of possible mercury （Hg） emission from two plants has been investigated. Potential atmospheric Hg emission has been determined based on an existing model for estimating the transport of mercury along geothermal fluid flow streams as pertains to energy recovery and conversion from liquid dominated geothermal reservoirs. Hg concentrations, addition, retention and release rates were calculated at a number of locations in the geothermal power plants based on the plant operating parameters and steam flow process （turbine, condenser, non-condensable gas ejector, and cooling tower）. Potential Hg emission rates through plume range from 0.455 g/h to 2.17 g/h, or 10-30 mg/h per MWe. The emission per hour per MWe is 130-300 times lower compared to Hg levels reported for 88 MWe five operating geothermal power plants around Mt. Amiata area in Italy. These emissions are coupled with a release of 1.07 kg/h per MW of hydrogen sulphide （HzS）. The potential Hg release rates to the environment will depend greatly on the concentration of HzS in the system. Any higher HzS contents may reduce solubility of rig in the brine hence making it to be available in the steam. The volatile Hg may travel with the non-condensable gases as Hg vapour.

High-entropy rare earth stannate ceramics:Acid corrosion resistant radiative cooling materials with high atmospheric transparency window emissivity and high near-infrared solar reflectivity

In response to the development of the concepts of“carbon neutrality”and“carbon peak”,it is critical to developing materials with high near-infrared(NIR)solar reflectivity and high emissivity in the atmospheric transparency window(ATW;8–13μm)to advance zero energy consumption radiative cooling technology.To regulate emission and reflection properties,a series of high-entropy rare earth stannate ceramics(HE-RE_(2)Sn_(2)O_(7):(Y_(0.2)La_(0.2)Nd_(0.2)Eu_(0.2)Gd_(0.2))_(2)Sn_(2)O_(7),(Y_(0.2)La_(0.2)Sm_(0.2)Eu_(0.2)Lu_(0.2))_(2)Sn_(2)O_(7),and(Y_(0.2)La_(0.2)Gd_(0.2)Yb_(0.2)Lu_(0.2))_(2)Sn_(2)O_(7))with severe lattice distortion were prepared using a solid phase reaction followed by a pressureless sintering method for the first time.Lattice distortion is accomplished by introducing rare earth elements with different cation radii and mass.The as-synthesized HE-RE_(2)Sn_(2)O_(7)ceramics possess high ATW emissivity(91.38%–95.41%),high NIR solar reflectivity(92.74%–97.62%),low thermal conductivity(1.080–1.619 W·m^(−1)·K^(−1)),and excellent chemical stability.On the one hand,the lattice distortion intensifies the asymmetry of the structural unit to cause a notable alteration in the electric dipole moment,ultimately enlarging the ATW emissivity.On the other hand,by selecting difficult excitation elements,HE-RE_(2)Sn_(2)O_(7),which has a wide band gap(Eg),exhibits high NIR solar reflectivity.Hence,the multi-component design can effectively enhance radiative cooling ability of HE-RE_(2)Sn_(2)O_(7)and provide a novel strategy for developing radiative cooling materials.

Atmospheric environmental capacity and urban atmospheric load in China's Mainland

Daily and annual average atmospheric environmental capacity coefficient(A-value) sequences for China's Mainland are calculated from hourly data recorded at 378 ground stations over 1975–2014. A-values at different recurrence intervals are calculated by fitting the sequences to Pearson type III distribution curves. Based on these A-values and source-sink balance(reference concentration 100 μg m^(-3)), atmospheric environmental capacities at the recurrence intervals are calculated for all of China's Mainland and each provincial administrative region. The climate average atmospheric environmental capacity reference value for the entire mainland is 2.169×10~7 t yr^(-1). An urban atmospheric load index is defined for analyses of the impact of population density on the urban atmospheric environment. Analyses suggest that this index is also useful for differentiating whether air quality changes are attributable to varying meteorological conditions or variations of artificial emission rate.Equations guiding the control of unorganized emission sources are derived for preventing air quality deterioration during urban expansion and population concentration.

Inventory of primary emissions of selected persistent organic pollutants to the atmosphere in the area of Great Mendoza

The setting up of a country or region-based inventory is considered a crucial step toward the elimination of worldwide persistent organic pollutants(POPs)contamination.Moreover,the need of comparable emission inventories at city or region level is widely recognized to develop evidence-based policies accounting for the relation between emissions and institutional,socio-economic and demographic characteristics at small scale level.Due to the low spatial and temporal resolution of the available measurements,highly variable air concentrations of several POPs have been observed in Latin American and Caribbean countries.This paper presents a high resolution spatially disaggregated atmospheric emission inventory for selected POPs in order to assess the environmental fate of some of these compounds in a finer resolution.As study case we estimated releases to air of POPs in a typical mid-size urban conglomeration in Argentina.Inventoried compounds were total polychlorinated biphenyls(PCBs),total polybrominated diphenyl ethers(PBDEs),total dichlorodiphenyltrichloroethane(DDT)on a sum basis,hexachlorobenzene(HCB)and dioxins and furans(PCDD/Fs),for which emissions were estimated in 0.92 kg/year,1.65 kg/year,4.2E-02 kg/year(total sum of congeners),0.86 kg/year and 4.4E-02 kg/year respectively,values that are in accordance with the geographic and economic context.Although emitting sources are quite varied,there are very clear trends,particularly in relation to open burning of municipal solid waste and agrochemical use as major contributors.Overall,the inventory provides valuable data for the analysis of the heterogeneity of POP emissions and the necessary inputs for air quality modeling.

Partitioning of rare earth elements and yttrium(REY)in five coal-fired power plants in Guizhou,Southwest China

As indispensable strategic materials for high-tech industries,rare earth elements and yttrium(REY)have become particularly important in recent years,raising the demand of developing new approaches for reclamation of REY from REY-rich materials such as coal combustion products(CCPs).In this study,five coal-fired power plants(CFPPs)in Guizhou of southwest China were selected for investigating REY concentrations of solid samples,atmospheric emissions,and recovery potentials.REY concentrations of feed fuels are higher in this study(147.2-468.6 mg/kg)than what have been reported previously for coals in China and the world.REY atmospheric emissions are extremely low(38.70-180.11 mg REY/t coal).REY are enriched in bottom ash and fly ash,with average of 658±296 mg/kg and maximum of 1257 mg/kg from the five CFPPs.Relative enrichment factors(REF)of REY in bottom ash and fly ash compared with the feed fuel are 0.86-1.02 and 0.91-1.04,respectively.REY concentrations in desulfurized gypsum are very low(6-17 mg/kg),and that is mostly inherited from limestone.Critical REY(Nd,Eu,Tb,Dy,Y,and Er)in bottom/fly ash account for 34%-39%of the total REY and the outlook coefficients(Cout1)are in the range of 0.89-1.11.This study indicates a promising prospect to reclaim REY from REYrich CCPs(bottom and fly ash)in CFPPs in Guizhou,especially in the central-north Guizhou,although such practices require further technology advancement.

The presence and partitioning behavior of flame retardants in waste,leachate,and air particles from Norwegian waste-handling facilities

Flame retardants in commercial products eventually make their way into the waste stream.Herein the presence of flame retardants in Norwegian landfills, incineration facilities and recycling sorting/defragmenting facilities is investigated. These facilities handled waste electrical and electronic equipment（WEEE）, vehicles, digestate, glass, combustibles, bottom ash and fly ash. The flame retardants considered included polybrominated diphenyl ethers（∑BDE-10） as well as dechlorane plus, polybrominated biphenyls, hexabromobenzene,pentabromotoluene and pentabromoethylbenzene（collectively referred to as ∑FR-7）. Plastic,WEEE and vehicles contained the largest amount of flame retardants（∑BDE-10： 45,000–210,000 μg/kg; ∑FR-7： 300–13,000 μg/kg）. It was hypothesized leachate and air concentrations from facilities that sort/defragment WEEE and vehicles would be the highest. This was supported for total air phase concentrations（∑BDE-10： 9000–195,000 pg/m^3 WEEE/vehicle facilities, 80–900 pg/m^3 in incineration/sorting and landfill sites）, but not for water leachate concentrations（e.g., ∑BDE-10： 15–3500 ng/L in WEEE/Vehicle facilities and 1–250 ng/L in landfill sites）. Landfill leachate exhibited similar concentrations as WEEE/vehicle sorting and defragmenting facility leachate. To better account for concentrations in leachates at the different facilities, waste-water partitioning coefficients, Kwastewere measured（for the first time to our knowledge for flame retardants）. WEEE and plastic waste had elevated Kwastecompared to other wastes, likely because flame retardants are directly added to these materials. The results of this study have implications for the development of strategies to reduce exposure and environmental emissions of flame retardants in waste and recycled products through improved waste management practices.