Total Particulate Matter Emissions Research Articles

Highly spatial and temporal bottom-up vehicle emission characterization and its control in a typical ecology-preservation area

The Chishui River Valley is a microscale ecology-preservation area with industrial clusters. The significance of evaluating vehicular emissions has been gradually highlighted with the rapid development of the local transportation and tourism sectors. This study provides the first estimates based on both bottom-up and top-down approaches. The annual total emissions of CO, NO x , hydrocarbons (HC), PM 10, and PM 2.5 in 2019 were 347.8, 189.6, 46.3, 6.9, and 6.3 Mg, respectively. Trucks contributed the most (55%) to the NO x emissions, followed by heavy-duty passenger vehicles (26%). In contrast, light-duty passenger vehicles and motorcycles generated 75% of the HC emissions. The superior accuracy of highly spatial and temporal bottom-up estimates versus top-down estimates is validated by the similar variation trends of hourly emission intensities and enhanced concentrations relative to background observations for both NO x and CO, with Pearson correlation coefficients between the intensities and concentrations ranging from 0.79 to 0.85. Historical HC emissions peaked in 2013, followed by a sharp decline in 2014 and a continuous rise since then, whereas NO x emissions have kept increasing since 2010. These indicated the necessity and urgency of effective vehicular emission mitigations. Based on scenario analysis, traffic restrictions combined with upgrading the emission standards of admitted vehicles will possess huge emission reduction potentials. Future recommendations about establishing a low emission zone in the valley and supporting policies were introduced. • On-road vehicle bottom-up emission intensity (EI) was built with a spatial resolution of 10 m × 10 m. • Temporal variations of bottom-up EI showed strong relationship with observations. • Bottom-up EI with traffic-flow data showed superiority to top-down estimate. • Traffic-restriction with stringent standards led to huge emission reduction benefits. • A low emission zone (LEZ) is proposed for a microscale area possessing ecology-preservation nature.

Combustion behaviour and slagging tendencies of pure, blended and kaolin additivated biomass pellets from fen paludicultures in two small-scale boilers < 30 kW

Pure, blended and additivated biomass pellets from four fen paludicultures were produced at TFZ and combusted in two small-scale biomass boilers (15 kW, 30 kW). Feedstocks derived from straw of Typha ssp., Phragmites australis, Phalaris arundinacea and Carex ssp. that were harvested during winter 2018, 2019 (used for pelletization) and 2020. Additivation of fuels with kaolin before pelletization or blending of fuels with ENplus wood pellets (A1 quality) after pelletization were applied. Straw and pellets were analyzed for physical and chemical fuel properties according to international standards for solid biofuels. Physical properties of pellets met the requirements of ISO 17225–6. Chemical properties of Typha indicated high TPM emissions due to high contents of K and Na in fuels while severe slagging was predicted for the other species by a high molar (Si + K + Al)/(Ca + Mg + P) ratio. During combustion in both boilers, CO and total particulate matter (TPM) emissions were high for Typha but slightly reduced by additivation with 2.3% kaolin. Blending of fuels significantly reduced NOX, SOX and HCl emissions due to lower N, S and Cl concentrations. Slagging was high for pure and additivated pellets of Phragmites, Phalaris and Carex with >50% of total ash consisting of particles >2 mm. No steady-state boiler operation could be achieved with either pure or additivated fuels. In conclusion, paludiculture pellets are challenging fuels for small-scale combustion plants. Their use cannot be recommended for the tested boilers. Technical solutions may be easier applied in medium sized combustions plants above 100 kW.

Brake wear induced PM10 emissions during the world harmonised light-duty vehicle test procedure-brake cycle

In this work, the particulate matter less than 10 μm (PM10) emissions from a medium-sized passenger vehicle's front brake wear were studied using a finite element analysis (FEA) and experimental approaches. The world harmonised light-duty vehicle test procedure-brake (WLTP-B) cycle was chosen to simulate real-world driving. An electrical low-pressure impactor (ELPI+) was used to count the brake wear particles on a brake dynamometer sealed in a chamber. In addition, a machine learning method, namely, extreme gradient boosting (XGBoost), was employed to capture the feature importance rankings of braking conditions contributing to brake wear PM10 emissions. The simulated PM10 emissions were quite consistent with the measured ones, with an overall relative error of 9%, indicating that the proposed simulation approach is promising to predict brake wear PM10 during the WLTP-B cycle. The simulated and experimental PM10 emission factors during the WLTP-B cycle were 6.4 mg km−1 veh−1 and 7.0 mg km−1 veh−1, respectively. Among the 10 trips of the WLTP-B cycle, the measured PM10 of trip #10 was the largest contributor, accounting for 49% of total PM10 emissions. On the other hand, the XGBoost results revealed that the top five most important factors governing brake wear PM10 emissions were dissipation energy, initial braking speed, final rotor temperature, braking power, and deceleration rate. From the perspective of friendly driving behaviour and regulation, limiting severe braking and high-speed braking has the potential to reduce PM10 emissions from brake wear.

County-level of particle and gases emission inventory for animal dung burning in the Qinghai–Tibetan Plateau, China

Emissions from animal dung burning in the Qinghai–Tibetan Plateau (QTP) influenced heavily on the regional and global climate and environment, from which the emission inventory of multiple pollutants is not yet available. This study developed a county-level emission inventory of particles and gases pollution based on field measured emission factors and detailed activity data for the QTP in 2019. The results revealed that the total emissions of particulate matter with an aerodynamic diameter of ≤2.5 μm (PM2.5), organic carbon (OC), elemental carbon (EC), eight ions, fifty-one polycyclic aromatic hydrocarbons (PAHs) in gaseous and particulate phases, 108 volatile organic compounds (VOCs), CO, and CO2 were 41.1, 23.1, 2.36, 3.15, 1.13, 6.55, 135, and 4963 Gg, respectively. Gonghe, Qilian, Nyima, and Gangcha Counties in northeast of Qinghai and northwestern Tibet were the major contributors of all pollutants contributed (accounting for 11.9%–14.6% of the total emission) due to their higher livestock numbers. Sheep dung burning contributed a little more (average of 67.1%) than yak dung burning (32.9%) due to the high EFs and consumptions. For temporal distribution, the heating season contributed majority of the total emissions (70%–82%). Although with much less population, the QTP showed even higher emission densities than those in plain areas due to less oxygen and poor combustion technology. Compared with existing emission inventories, the uncertainties of all pollutant emission inventories were considerably reduced (42.7–163%), with EC as an exception because of its high coefficients of variation of EFs than the other pollutants. The developed emission inventory can help formulate targeted air pollution control measures for the QTP region by providing detailed information on the spatiotemporal distribution of multitype air pollutants. Meanwhile, the relative high resolution and accuracy inventory could serve a better basis for atmospheric modeling such as pollution transportation and source apportionment in both regional and global scales.

Comparison of total PM emissions emitted from electric and internal combustion engine vehicles: An experimental analysis

Electric vehicles (EVs) are regarded as zero emission vehicles due to the absence of exhaust emissions. However, they still contribute non-exhaust particulate matter (PM) emissions, generated by brake wear, tire wear, road wear, and resuspended road dust. In fact, because EVs are heavier than internal combustion engine vehicles (ICEVs), their non-exhaust emissions are like to be even higher. While total PM emissions, including exhaust and non-exhaust PM emissions, from ICEVs and EVs have been compared based on the emission factors (EFs) listed in national emission inventories, there have been no comparisons based on experimental determinations.In this study, exhaust and non-exhaust emissions generated from a gasoline ICEV, diesel ICEV, and EV were experimentally investigated. The results showed that the EFs for the total PM emissions of ICEVs and EV were dependent on the inclusion of secondary exhaust PM, the brake pad type, and the regenerative braking intensity of the EV. When only primary exhaust PM emissions were considered in vehicles equipped with non-asbestos organic (NAO) brake pads, the total PM10 EF of the EV (47.7–49.3 mg/V·km) was 10–17 % higher than those of the gasoline ICEV (42.3 mg/V·km) and diesel ICEV (43.2 mg/V·km). However, in vehicles equipped with low-metallic (LM) brake pads, the total PM10 EF of the EV (49.2–57.7 mg/V·km) was comparable or lower than those of the gasoline ICEV (56.3 mg/V·km) and diesel ICEV (57.2 mg/V·km). When secondary PM emissions were included, the EF was always significantly lower for the EV than ICEVs. The total PM10 EF of the EV (47.7–57.7 mg/V·km) was lower than those of the gasoline ICEV (56.5–70.5 mg/V·km) and diesel ICEV (58.0–72.0 mg/V·km). Since secondary PM particles are mostly of submicron size, the EFs of the PM2.5 fraction of the ICEVs (28.7–33.0 mg/V·km) were two times higher than those of the EV (13.9–17.4 mg/V·km).

Monitored air pollutants from waste-to-energy facilities in China: Human health risk, and buffer distance assessment

China is progressively using incineration to manage municipal solid waste (MSW). However, the associated air pollution and health risks have received little attention. Furthermore, the current buffer protection may no longer significantly mitigate people's exposure to harmful air pollutants. Consequently, this study explores the emission characteristics of five monitored pollutants PM, SO2, NOx, CO, and HCl, as well as heavy metals generated by 510 incineration plants. The hazard index (HI) assessment included Cd, As, Cr, Ni, Pb, and Hg, whereas the cancer risk (CR) included Cd, As, Cr, and Ni. Our results show a decreasing trend in the total emissions of PM, SO2, and CO from 2015 to 2020. At 1 km downwind, the national average HI was 1.06, slightly above the recommended HI threshold (HI ≤ 1). In addition, the national average CR was beyond the safe level of 1 × 10−4 (CR = 5.69 × 10−3). The multicriteria decision tool, RAFSI, indicates 1.5 km as the best alternative buffer protection distance for an acceptable risk level. This finding suggests a potential reevaluation of the minimum buffer distance.

A Comprehensive Analysis of Inorganic Ions and Their Selective Removal from the Reconstituted Tobacco Extract Using Electrodialysis.

Many tobacco stalks, dust, and fines are discharged in the tobacco industry, rich in inorganic minerals ions and nicotine salts. The high salinity and nicotine salts are challenging to be addressed by traditional treatment and are a severe threat that ought to be overcome. Thus, proper techniques can regenerate the tobacco stalks into reconstituted tobacco flakes used as cigarette filler. The electrodialysis process has been a viable approach to removing the inorganic ingredients in wastewater. We studied concentration, pH, and co-related influences with the nicotine and sugar/nicotine contents on the desalination performance. The results show that the inorganic ions such as Cl−, K+, Ca2+, and Mg2+ ions were successfully removed. When the feed concentration ranges from 3 to 15%, the removal ratio of the K+ ions is higher than Ca2+ and Mg2+ ions. As we reported previously, the K+ and Ca2+ ions are unfavorable for the total particulate matter emission but beneficial to decreasing the HCN delivery in mainstream cigarette smoke. Selective ED is a robust technology to reduce the harmful component delivery in cigarette smoke.

Source emission and attribution of a large airport in Central China

Large airport operation release harmful air pollutants and have adverse impact on local air quality. As one of the world's top 30 busiest airports, Xinzheng International Airport (CGO) located in Zhengzhou City, China, its emission impacts needs particular attention. To identify the possible impacts and quantify the contribution of CGO airport to air pollution, a comprehensive approach including emission inventory, continuous monitoring, coupled with statistical modelling was adopted in this study. We estimated a more detailed emissions inventory for CGO, including hourly and annual emissions from engines and auxiliary power units of aircrafts during landing and take-off flight, and airside ground support equipment (GSE) in 2019. The results indicate that almost all the CGO specific parameters including operating hours, fuel consumption and unit LTO emissions at different modes were lower than ICAO reference values. The annual total emissions of NOx, CO, HC, SO2 and PM from CGO from aircrafts and GSE were 1207.7, 921.3, 123.7, 268.3 and 36.2 tons, respectively. In addition to SO2, the main engines of the aircraft accounted for 80.3%, 62.6%, 45.5% and 74.3% of the total emissions, respectively. Meanwhile, a continuous monitoring campaign was conducted for one year in the vicinity of CGO airport. The monitoring data were analyzed using generalized additive model (GAM) to quantify the impact of NOx emissions from airport activities on air quality at CGO. The results showed that even the influence of environmental and meteorological variables was greater, nearly 13% of the ambient NOx concentrations were explained by emissions from airport activities, indicating the importance of airport-related emissions as the major source affecting local air quality.

Suggestion on further strengthening ultra-low emission standards for PM emission from coal-fired power plants in China

China has established the largest clean coal-fired power generation system in the world by accomplishing the technological transformation of coal-fired power plants (CFPPs) to achieve ultra-low emission. The potential for further particulate matter (PM) emission reduction to achieve near-zero emission for CFPPs has become a hotspot issue. In this study, PM emission from some ultra-low emission CFPPs adopting advanced air pollutant control technologies in China was reviewed. The results revealed that the average filterable particulate matter (FPM) concentration, measured as the total particulate matter (TPM) according to the current national monitoring standard, was (1.67±0.86) mg/m3, which could fully achieve the ultra-low emission standard for key regions (5 mg/m3), but that achieving the near-zero emission standard was difficult (1 mg/m3). However, the condensable particulate matter (CPM), with an average concentration of (1.06±1.28) mg/m3, was generally ignored during monitoring, which led to about 38.7% underestimation of the TPM. Even considering both FPM and CPM, the TPM emission from current CFPPs would contribute to less than 5% of atmospheric PM2.5 concentrations in the key cities and regions in China. Therefore, further reduction in FPM emission proposed by the near-zero emission plan of CFPPs may have less environmental benefit than emission control of other anthropogenic sources. However, it is suggested that the management of CPM emission should be strengthened, and a national standard for CPM emission monitoring based on the indirect dilution method should be established for CFPPs. Those measurements are helpful for optimal operation of air pollutant control devices and continuously promoting further emission reduction.

Emission inventory for road transport in India in 2020: framework and post facto policy impact assessment.

India's growing population and economic development lead to an increase in transport emissions. Quantification of emission at frequent intervals is required to assess the emission levels and impact of implemented control policies. Implemented policies affect the fleet configuration over time. Therefore, in the present paper, an age-wise emission analysis framework is developed for the road transport sector with updated fleet characteristics corresponding to the vehicles' age. The results show that fuel consumption is estimated to be 92 (87-95) Mt, and total CO2, CO, PM, and NOx vehicle emissions are estimated to be 274 (265-292) Tg, 4463 (3253-6676) Gg, 164 (119-250) Gg, and 2378 (2191-3045) Gg, respectively for the reference year 2020. The study contributes by developing an inventory for the fleet of 2020, which is used as a benchmark to compare past emission inventory, evaluate control policies, estimate state-wise vehicle emission inventories, and identify significant emitters in the fleet. Sensitivity analysis indicates the considerable variation in total emissions resulting from different age-mix of vehicles. Among the investigated policies, advancement in emission norms followed by fuel efficiency improvement in vehicles led to a substantial reduction in gaseous pollutants. Based on the inventory results, suitable policies are suggested for India's future fleet, and the need for country-level fleet characteristics data is recommended.

Probabilistic total PM2.5 emissions from vehicular sources in Australian perspective.

Motor vehicles operating on the road are a significant source of Particulate Matter (PM) emissions depending on the fuels used in the vehicles. Gasoline and Diesel vehicles are directly responsible for the tailpipe PM emissions (specifically PM2.5: particles ≤ 2.5µm), known as primary PM2.5 emissions. The other major direct emissions from the vehicles, which include volatile organic compounds (VOCs), and nitrogen oxides (NOx) contribute to the formation of secondary organic PM, also known as secondary organic aerosols (SOA), through some inter-related chemical reactions. The SOAs are highly toxic and contribute to a portion of total PM emissions. In this research, emission scenarios of both primary PM2.5 and SOA for a car-dependent expanding Australian city (Adelaide) were analyzed. The variability of traffic characteristics on road was considered and conducted a probabilistic emissions inventory for tailpipe primary PM2.5 and precursors, while statistical analysis of the probable chemical conversion ratios was considered for the SOA inventory. It was found that the tailpipe emissions from the vehicles were higher than the air quality standard, while the SOA contribution from the vehicles was not significantly high but contributed to the increase of total PM concentration. The analysis of the chemical transformation of SOA precursors justified the importance of conducting more detailed emissions modelling for sustainable urban air quality planning.

Highly-resolved spatial-temporal variations of air pollutants from Chinese industrial boilers

Industrial boilers are a significant anthropogenic source of air pollutant emissions. In this study, a county-based atmospheric emission inventory of particulate matter (PM), PM10, PM2.5, SO2, NOx, organic carbon (OC) and elemental carbon (EC) from industrial boilers over mainland China in 2017 was developed for the first time, based on county-level activity data from ~61,000 coal-fired industrial boilers (CFIBs), ~44,000 biomass-fired industrial boilers (BFIBs), ~71,000 gas-fired industrial boilers (GFIBs) and ~9300 oil-fired industrial boilers (OFIBs), updated emission factors (EFs) and air pollution control device (APCD) efficiencies. The total national PM, PM2.5, PM10, SO2, NOx, OC and EC emissions from industrial boilers in 2017 were estimated to be 1,240, 347, 761, 1,648, 1,340, 13.1 and 15.8 kilotons (kt), respectively. Intensive air pollutant emissions from industrial boilers of more than 1000 kg/km2 were predominantly in north-eastern, northern and eastern China. CFIBs contributed the most (77.6–94.0 %) to air pollutant emissions because of their high air pollutant EFs and the large amounts of coal consumed. BFIBs were the second-highest contributor to national air pollutant emissions, with the contribution of BFIBs to PM2.5, OC and EC emissions in central and southern China reaching up to 42.1 %, 61.7 % and 45.5 %, respectively. There were seasonal peaks in monthly air pollutant emissions in heating regions. The overall uncertainty realting to the new emission inventory was estimated as −25.9 %–22.7 %. Significant air pollutant emission reductions were obtained from 2017 to 2030, and by 2030 the PM, PM10, PM2.5, SO2 and NOx emissions were forecast to decrease by 40.1–84.0 %, 41.6–84.3 %, 44.5–75.2 %, 44.5–75.2 % and 19.5–46.8 % compared to 2017, respectively, under four proposed scenarios. The results of this study showed that differentiated industrial boiler management measures should be developed according to the actual emission characteristics.This work developed a county-based atmospheric emission inventory of PM, PM10, PM2.5, SO2, NOx, OC and EC from Chinese industrial boilers in 2017 for the first time.

Fuel Improvement Measures for Particulate Matter Emission Reduction during Corn Cob Combustion

Fuel-related measures and modernization of small-scale combustion units has become the focus of attention in the renewable heat generation sector, as a means to promote local biomass utilization and fuel-flexibility while meeting strict environmental legislative requirements. With the aim to mitigate total particulate matter emissions and ash-associated problems characteristic of crop residue combustion, (1) corn cob pellets (with and without kaolin and binder) as well as (2) fuel blends with wood pellets were combusted in a pellet oven under full load. Results show that additivation or fuel blending (e.g., 50 wt. % wood and 50 wt. % corn cob pellets) reduce total particulate and CO-emissions by 48 to 60 wt. % and 64 to 89 wt. %, respectively, in comparison to baseline emissions from non-additivized corn cob pellets. Kaolin prevented sintering of corn cob ash. However, considerable grate ash entrainment was observed. TPM consists of a “primary network”—polyhedral and spherical particles approximately 1 μm in diameter (mainly KCl), and a “secondary network” built on top of the primary network, consisting of square-prism-shaped particles of approximately 200 nm in diameter. KCl and K2SO4 are main compounds in particles from corn cob and wood pellet combustion, respectively. Effective measures demonstrated within this study should be complemented with low-cost coarse ash removal systems.

Application and validation of the fugitive dust source emission inventory compilation method in Xiong'an New Area, China

The development of a refined fugitive dust emission inventory is vital for prevention and control of air pollution. In this study, a fugitive dust emission inventory of soil dust (SD), road dust (RD), and construction dust (CD) in Xiong'an New Area (XANA) for 2020 was developed by collecting activity data and combining remote sensing and field investigation data based on a popular compilation technology in China. The CALPUFF model was used to elucidate the contribution characteristics of dust sources to ambient particulate matter (PM), and the accuracy of the dust emission inventory compilation method was verified. The results show that the total emissions of PM10 and PM2.5 were 43,081.14 tons and 9701.69 tons, respectively. Meanwhile, RD and CD were the main emission sources, accounting for over 98.49% of the total emissions. The total contribution from the different types of dust sources to the ambient PM10 was 42.59 μg/m3 (29.38%), with the contribution of RD (32.63 μg/m3, 22.51%) being approximately three times that of CD (9.78 μg/m3, 6.74%). Roads were the main source of fugitive dust, but large-scale infrastructure construction was the main cause of the high emission and high contribution of RD. The results show that the emission inventory compilation method can be used to estimate the emissions of dust sources, while the method used to calculate the emission of SD may be more suitable for dry and semi-dry areas with less rainfall. It was also found that when the dust emissions stay stable, the contribution of dust sources to the ambient PM10 in different seasons can vary by 3–4 times. Therefore, under adverse meteorological conditions, it is necessary to strengthen the control of various dust sources and reduce the influence of human factors on them.

Influence of Ca- and Al-additives on the pollutant emissions from blends of wood and straw in small-scale combustion

In the last few years, biomass has become increasingly important as a constantly available, renewable and CO2-neutral energy carrier. A growing sector is the combustion of biomass in small-scale combustion plants (<100 kW). If the growth of this sector continues, there may be a shortage of the resource biomass in the future. Another challenge related to biomass combustion is the clearly higher release of total particulate matter (tPM) emissions due to the higher content of aerosol forming elements in biomass fuels (especially the content of potassium) compared to fossil fuels like oil and gas. Thus, the threshold values especially for such airborne pollutants released from biomass combustion, especially wood, in small-scale combustion plants are being tightened more and more. Therefore, the aim of the present work is to investigate the influence of the additive CaHPO4, in comparison of the well-known additive kaolin (amount of 0.5 wt%), on the pollutant formation (tPM and CO) of beech wood and blends of beech wood and barley straw (with a proportion of up to 20 wt%) during combustion in a small-scale combustion plant (8 kW). The measurements show considerable reduction effects of both additives for the CO and total PM emissions. For example, the total PM emissions of the pure wood sample can be reduced with the additive kaolin by about 60%. For the blends of wood and straw the additive CaHPO4 shows an effective reduction effect of 50% (10 wt% straw/90 wt% wood) and of 40% (20 wt% straw/80 wt% wood). By contrast, a significant reduction of more than 50% of CO emissions can be achieved in all samples with the help of the additive kaolin.

Emission Concentration and Characteristics of Particulate Matter and Water-Soluble Ions in Exhaust Gas of Typical Combustion Sources with Ultra-Low Emission

A self-developed direct condensation sampling system and monitoring method for total particulate matter (TPM) in ultra-low-emission and high-humidity exhaust gas were applied to the emission monitoring of particulate matter in flue gas from three typical combustion sources with ultra-low emissions in Beijing. The emission levels and composition characteristics of particulate matter and water-soluble ions in the exhaust gas of typical combustion sources with ultra-low emissions were analyzed and evaluated. The interaction and influencing factors of filterable particulate matter (FPM) and condensable particulate matter (CPM) and their water-soluble ions were explored. The results showed that the emission concentration of FPM in the exhaust gas of the coal-fired boiler with ultra-low emissions was between 1.04 mg·m-3 and 1.11 mg·m-3 in standard smoke oxygen content, and that of TPM was between 3.82 mg·m-3 and 8.69 mg·m-3, which all met the national ultra-low emission limit (10 mg·m-3). However, the TPM emission concentration of the coal-fired power plant exceeded the emission limit of Beijing (5 mg·m-3). The emission concentrations of CPM and its total water-soluble ions from the coal-fired heating boiler were 3.05 mg·m-3 and 1.30 mg·m-3, respectively, which were significantly lower than those of the coal-fired power plant, and were related to the higher load and flue gas temperature of the coal-fired power plant. Furthermore, the emission concentrations of CPM and its total water-soluble ions from the coal-fired power plant boiler were 2.2 to 2.4 times and 1.7 to 2.2 times greater than those of the coal-fired heating boiler, respectively. The emission concentrations of TPM and its total water-soluble ions from the gas power plant were 1.99 mg·m-3 and 1.44 mg·m-3, respectively, which were significantly lower than those from the coal-fired boiler. CPM was the main form of particulate matter in the exhaust gas of the combustion source. The contribution of CPM to TPM in the ultra-low-emission boiler flue gas increased significantly, and increased with the increase in the flue gas temperature, ranging from 72.6% to 88.1% for the coal-fired boiler and 93.1% for the gas power plant. Total water-soluble ions made up 66.1% to 94.2% of the CPM. The flue gas temperature had a significant impact on the existing forms, removal efficiencies, and emission concentrations of particulate matter and water-soluble ions. SO42- was the main characteristic water-soluble ion of particulate matter in the coal-fired boiler, and its emission concentration ranged from 0.98 mg·m-3 to 1.18 mg·m-3, accounting for 27.7% to 49.6% of the total water-soluble ion emissions, which originated from flue gas desulfurization. F- was another characteristic water-soluble ion of particulate matter in the coal-fired power plant, and its emission concentration ranged from 1.91 mg·m-3 to 2.32 mg·m-3, accounting for 54.4% to 56.1% of the total water-soluble ion emissions, which might have been related to the high F content of fuel coal. NH4+ was the main characteristic water-soluble ion of particulate matter in the gas power plant, and its emission concentration was 0.92 mg·m-3, accounting for 64.2% of the total water-soluble ion emissions, which originated from the escape of NH3 in the process of selective catalytic reduction. The emission concentration of NH4+ was significantly higher than that of the coal-fired boiler; this might have been related to the synergistic removal effect of the gas-fired power plant, which lacked other purification facilities.

Characterization of emissions of condensable particulate matter under real operation conditions in cement clinker kilns using complementary experimental techniques

Historically, the emission of particles from clinker kiln stacks has been one of the main environmental concerns in cement manufacturing processes. Up to now, environmental regulations have only focused on determining and controlling filterable particulate matter (FPM) in industrial emission sources. However, in recent years a growing interest in determining and analysing condensable particulate matter (CPM) has been evidenced due to the significant and established contribution of CPM to total emissions of particulate matter (PM).In this work, total PM (FPM + CPM) emissions from a clinker kiln in a cement manufacturing process have been characterized. A series of tests were performed to simultaneously collect FPM and CPM using a sampling train patented by University of Seville. The results showed very low level of emissions compared to regulatory limits. The average FPM and CPM concentrations obtained in the kiln were in the same order of magnitude, at 3.4 mg/Nm3 and 2.8 mg/Nm3, respectively. The CPM analysed was predominantly inorganic and represented 46% of total PM emissions.In addition, a microscopic morphological analysis was carried out on the samples and confirmed the presence of CPM with a size of less than 2 μm, as well as establishing the principal constituent elements of the same. The main element components were Al, Ca, Fe, Si, C and O. Compounds such as CaCO3, alite, ferrite and dolomite were detected with analytical characterization techniques, such as infrared spectroscopy (FTIR) analysis and X-ray diffraction (XRD), providing a better understanding of the sources of contamination within CPM.

Effect of Utilizing a Novel Intake Manifold Design on Smoke Emissions and Particulate Size Distributions of a Gas-to-Liquid (GTL) Diesel Engine

Abstract Smoke emissions and particulate matter (PM) size distributions were investigated on a direct-injection single-cylinder diesel engine running on both gas-to-liquid (GTL) and diesel fuels utilizing a novel spiral-helical intake manifold design. Smoke opacity was measured at a wide range of engine loads and speeds with both fuels to examine the effect of using the new manifold on smoke emissions. In addition, total PM numbers of fine particles (PM diameter = 1.0 µm) and coarse particles (&amp;gt;1.0 µm) were quantified with both fuels. Moreover, high-resolution transmission electron microscopy (HRTEM) images were taken with different resolutions to observe the PM sizes produced from each fuel when using the new and normal manifolds. The results showed that using the novel manifold reduced smoke emissions for both GTL and diesel fuels with about 36% at low loads and 7% at high loads. However, using the new manifold with GTL fuel showed superior performance to reduce smoke with about 60% at low loads and 10% at high loads. For the PM size distribution, the new manifold reduced total PM emissions in general. However, significant reductions were obtained with fine PM sizes (0.3 – 1.0 µm) when GTL fuel was used with about 30% for constant load tests, and about 40% for constant speed tests. On the other hand, the new manifold tended to increase slightly the coarse PM sizes. The HRTEM images of the PM structure for both manifolds and fuels have confirmed the above results.

Air pollutant emissions from the asphalt industry in Beijing, China

Improving our understanding of air pollutant emissions from the asphalt industry is critical for the development and implementation of pollution control policies. In this study, the spatial distribution of potential maximum emissions of volatile organic compounds (VOCs) in the complete life cycle of asphalt mixtures, as well as the particulate matter (PM), asphalt fume, nonmethane hydrocarbons (NMHCs), VOCs, and benzoapyrene (BaP) emissions from typical processes (e.g., asphalt and concrete mixing stations, asphalt heating boilers, and asphalt storage tanks) in asphalt mixing plants, were determined in Beijing in 2017. The results indicated that the potential maximum emissions of VOCs in the complete life cycle of asphalt mixtures were 18,001 ton, with a large contribution from the districts of Daxing, Changping, and Tongzhou. The total emissions of PM, asphalt fume, NMHC, VOCs, and BaP from asphalt mixing plants were 3.1, 12.6, 3.1, 23.5, and 1.9 × 10−3 ton, respectively. The emissions of PM from asphalt and concrete mixing stations contributed the most to the total emissions. The asphalt storage tank was the dominant emission source of VOCs, accounting for 96.1% of the total VOCs emissions in asphalt mixing plants, followed by asphalt heating boilers. The districts of Daxing, Changping, and Shunyi were the dominant regions for the emissions of PM, asphalt fume, NMHC, and BaP, while the districts of Shunyi, Tongzhou, and Changping contributed the most emissions of VOCs.

Study on the distribution of PM emission rights in various provinces of China based on a new efficiency and equity two-objective DEA model

Under the premise that the total emissions of PM(particulate matter) of air pollution is established, the allocation of PMemission rights in various provinces of China is the feasible way to governance the ash haze. In this paper, a data envelopment analysis (DEA) model that takes into account the objectives of efficiency and equity is constructed. On the basis of evaluating the PMemission performance of various provinces in China, the corresponding allocation steps are put forward. Then, the results of theDEAmodel and information entropy are compared. The research shows that: (1) under the same constraint conditions, the emission right of PMis allocated with DEA model, which leads to lower cost, less fluctuation of distribution amount and higher overall national performance. (2) the populationGinicoefficient method is used to evaluate and it is found that the Gini coefficient value is smaller according to the distribution results of DEA model, indicating that the PM emission right amount is more fairly distributed among provinces. The functions of this paper are as follows: (1) a new double-objective DEA model is constructed, which is suitable for multi-agent performance evaluation with multiple objectives; (2) a scheme to allocate PM among provinces is proposed, which can provide reference for the practice of haze reduction in China