Reduction Of Particulate Matter Emissions Research Articles

Reduction in PM and NOX of a diesel engine integrated with n-octanol fuel addition and exhaust gas recirculation

n-Octanol with its high energy density and high cetane number has similar fuel properties as diesel fuel, and is thus considered an excellent choice for alcohol fuels as a substitute for diesel. This study focused on the effects of exhaust gas recirculation (EGR) combined with the addition of n-octanol on the performance, emissions, and particulate matter (PM) of a direct injection diesel engine. The results show that the curves of the in-cylinder pressure of n-octanol/diesel blends nearly overlap those of pure diesel fuel under the test conditions. At a low EGR ratio, the brake thermal efficiency of n-octanol/diesel blends is higher than that of diesel fuel. With an increase in the EGR ratio, the results show that nitrogen oxide (NOX) emissions decrease, whereas carbon monoxide (CO) and soot emissions significantly increase. However, the use of n-octanol/diesel blends can inhibit the increase in CO and soot emissions appreciably. In addition, with an increase in n-octanol content in the blends, the number concentration of particles on the particle size distribution decreases gradually. To summarize, a simultaneous reduction in NOX and PM emissions under a combined operation of small EGR ratios and n-octanol blends can be realized, thereby improving the brake thermal efficiency.

Investigation of formation mechanism of particulate matter in a laboratory-scale simulated cement kiln co-processing municipal sewage sludge

The integrated utilization of wastes in a cement kiln has become an international megatrend. Various hazardous compounds containing in wastes might be enriched in the particulate matter (PM) emitted during the waste disposal and cause adverse environmental consequences. In order to evaluate the potential environmental issues caused by the PM emission from the cement kiln for co-processing wastes, the chemical characteristics and formation mechanism of the PM was investigated for the first time by using a laboratory-scale tube furnace to simulate this process. PM was collected to analyze the major components (heavy metals, inorganic and organic components) and morphologies. The results reveal that volatile heavy metals in municipal sewage sludge (MSS) can be enriched in PM. The process can elevate the levels of sulfate and the organic contents in PM, and the existence of organic moieties such as CN+ and CHN+ suggest that the co-processing of MSS can affect the PM organic compositions. Single particle imaging analyses indicate that PM can be classified into nine types based on their elemental compositions. Further analysis reveals that most particles usually mix with other types of particles and those mixed particles may cause a more serious impact on the environment. Based on the TEM observation, a two-step formation mechanism of PM is proposed. Our findings point out the potential environmental adverse effects and call attentions to a full environment assessment of this new type of cement production process, and also indicates stringent measures should be taken to reduce PM emissions during this process.

An Overview of the Influence of Biodiesel, Alcohols, and Various Oxygenated Additives on the Particulate Matter Emissions from Diesel Engines

Rising pollution levels resulting from vehicular emissions and the depletion of petroleum-based fuels have left mankind in pursuit of alternatives. There are stringent regulations around the world to control the particulate matter (PM) emissions from internal combustion engines. To this end, researchers have been exploring different measures to reduce PM emissions such as using modern combustion techniques, after-treatment systems such as diesel particulate filter (DPF) and gasoline particulate filter (GPF), and alternative fuels. Alternative fuels such as biodiesel (derived from edible, nonedible, and waste resources), alcohol fuels (ethanol, n-butanol, and n-pentanol), and fuel additives have been investigated over the last decade. PM characterization and toxicity analysis is still growing as researchers are developing methodologies to reduce particle emissions using various approaches such as fuel modification and after-treatment devices. To address these aspects, this review paper studies the PM characteristics, health issues, PM physical and chemical properties, and the effect of alternative fuels such as biodiesel, alcohol fuels, and oxygenated additives on PM emissions from diesel engines. In addition, the correlation between physical and chemical properties of alternate fuels and the characteristics of PM emissions is explored.

Experimental study of PM emissions from wood pellet stoves with an innovative burning pot

In this study, results of an extensive set of experiments on a wood pellet stove model equipped with innovative burning pots are presented. Tests have been performed to investigate the relations between design data and operation parameters of the stove and its emissions. In particular, carbon monoxide (CO) and particulate matter (PM) emissions are correlated to the burning-pot depth.The burning pot A, adopted by AICO S.p.A, allows to obtain near-to-zero CO emissions and low PM emissions: however, PM emissions reduction with respect to standard burning pots is not as enhanced as CO emission reduction. Here it is shown that a further reduction of PM emissions (down to 6-16 mg/Nm3) can be attained increasing the burning pot depth.Experiments show also an increment of PM emissions in subsequent tests in the same day: there is an apparent dependence of PM release on the time from ignition. It is likely that this effect is due to ashes accumulation on the bottom of the burning pot and to their interaction with the primary air stream that flows over them.

Influence of fuel-oxygen content on morphology and nanostructure of soot particles

The share of biofuels in the fuel market has increased over the last several decades. This is related to their potential to reduce the emissions including particulate matter. It has been frequently reported that the fuel oxygen content is the main reason for the reduction in particulate matter emissions. To understand the effect of fuel oxygen content on morphology and nanostructure characteristics of soot particles, different fuels such as diesel, coconut biodiesel and triacetin were tested in a diesel engine with various mixing proportions. The fuel blending was done in such a way that overall oxygen content of fuel was kept in range of 0% to 14% (wt.%). The soot particles were sampled from the engine exhaust system and analysed with a transmission electron microscope (TEM) at low and high spatial resolution. The TEM images were post-processed with the help of an in-house developed image analysis program to determine the morphology and nanostructure characteristics. The results show that oxygenated fuel blends emit smaller sized soot particles forming compact aggregates. The investigation of the internal structure of soot particles show disordered arrangement of graphene layers for fuels up to 11.01% fuel oxygen content (pure biodiesel); however, the opposite trend was observed for fuel blends with triacetin which could be related to the presence of oxygen in a different chemical functional group.

Effect of Polyoxymethylene Dimethyl Ethers/Diesel Blends on Fuel Properties and Particulate Matter Oxidation Activity of A Light-Duty Diesel Engine

Polyoxymethylene dimethyl ethers (PODE) was blended in diesel at volume ratios of 0 %, 10 %, 20 %, and 30 % (denoted as P0, P10, P20, and P30). The experimental study was carried on an unmodified YD480Q diesel engine. An engine exhaust particle sizer was introduced to analyze the particulate matter (PM) concentration and particle size distribution of diesel engine emission. The evaporation-oxidation characteristics of the PODE/diesel blends and the effect of the fuel blends on the oxidative activity of PM were investigated by thermogravimetric analysis and Arrhenius theorem. The results showed that blending PODE in diesel improved the evaporation-oxidation characteristics of the fuel and decreased the apparent activation energy of the fuel blends. PODE played a positive role in reducing PM emissions. The particle total number concentration of P30 decreased 28.29 ~ 66.60 % and the particle total volume density decreased 54.16 ~ 80.06 % compared to diesel. The particle size distribution shifted to a smaller particle size as the PODE blending ratio was increased. The mass fraction of the volatile substances (VS) increased and the mass fraction of the dry soot (DS) decreased by employing PODE as a diesel additive. Also, the oxidation activity of VS increased as the PODE blending ratio was increased. The oxidation activity of DS climbed to the peak when the PODE blending ratio was 20 % and then decreased.

Investigation of reducing particulate matter (PM) and heavy metals pollutions by adding a novel additive from metallurgical dust (MD) during coal combustion.

In this study, a novel additive from metallurgical dust(MD)was applied to reduce particulate matter (PM) emissions and heavy metals pollutions during coal combustion. PM samples were collected and divided into 13 stages from 0.03 μm to 10 μm. Results showed that the irregular morphology of fine particles with equal to/less than 2.5 μm (PM2.5), fine particles with equal to/less than 4 μm (PM4) and fine particles with equal to/less than10 μm (PM10) gradually became dense with increasing of MD content. The PM10 concentration with 10% MD dosage was about 3 times higher than that of raw coal. Zn, Ti, Cu and Cr were the most abundant elements in all particulate matters (PMs), meanwhile, heavy metals accumulated into large particles with increasing MD content. The mechanism of reducing PM emissions indicated that MD reacted with nucleation elements (Pb, Cd, etc.) and trapped a large amount of alkali metal (Na/K), which aggregated into large particles. The study highlights the potential of adding MD into coal to prevent the attachment of heavy metals onto ultrafine particles, thereby reducing the heavy metals emissions.

Performance and emission characteristics of a compression ignition (CI) engine operated with beauty leaf biodiesel

In this investigation, diesel and beauty leaf (Calophyllum inophyllum L.) biodiesel (BLB)-diesel blends (B5, B10 and B20) were used to evaluate the performance and emission characteristics of a compression ignition (CI) engine. During the experiment, the speed of the engine was varied from 1200 rpm to 2400 rpm at 200 rpm interval. The results indicated that the performance characteristics, such as BP and BSFC in biodiesel blended fuel increases with increase in engine speed at full load condition with a few exceptions in BSFC at 1400 rpm. On the other hand, BTE and BMEP in biodiesel blended fuel decreases with increase in engine speed at 100% load with few exceptions at 1400 rpm. The results also revealed that the BP, BTE and BMEP are lower, whereas, the BSFC is higher in biodiesel blended fuel in comparison to diesel. In terms of emission characteristics, the results indicated that the emission of nitrogen oxides (NOx) increases, whereas, carbon monoxide (CO), hydrocarbon (HC), and particulate matter (PM) decreases with increase in engine speed at full load condition. The results also shown that the use of biodiesel-diesel blends in CI engine led to the significant reduction in CO, HC and PM emissions in comparison to conventional diesel. On the other hand, it has been observed that the NOx emissions are increased in biodiesel-diesel blends when they are compared to diesel.

Potential improvement in particulate matter’s emissions reduction from diesel engine by addition of PODE and injection parameters

Particulate matter (PM) emitted from conventional diesel engines has significant deteriorating effects on natural environment and human health. Among alternative oxygenated fuels, polyoxymethylene dimethyl ether (PODE) is a novel renewable fuel with high cetane number, oxygen content and volatility, and has prominent potential for reducing the PM emissions. In this study, the influences of fuel injection parameters, including injection pressure and injection timing on the reduction of PM emissions were explored for a four-cylinder diesel engine fueled with PODE/diesel blends at various engine loads. The three blends were the pure diesel (denoted as P0), a mixture of 80% diesel and 20% PODE (denoted as PD20), and the mixture of 70% diesel and 30% PODE (denoted as PD30). The results showed that adding PODE to diesel resulted in a reduction in both the total particle number concentration (PNC) and the particle mass concentration (PMC) at all loads. For the PODE/diesel blends, at low load and higher injection pressures, the PMC further decreased, although the value of PNC drastically increased. For the PODE/diesel blends, at medium load and higher injection pressures, both the PNC and PMC values decreased. When the injection pressure was higher than 120 MPa, it could not continuously reduce PNC. Furthermore, for the PODE/diesel blends, at high load and high injection pressures, both the PNC and PMC values greatly decreased. The PODE/diesel blends coupled with the retarded injection timing could reduce the PNC and PMC values, but when the injection timing occurred too close to the top dead center (TDC), the PNC value increased. In addition, as the injection timing was closer to TDC, the effect of the addition of PODE in diesel fuel on reducing PNC and PMC became more significant.

On-Board Ultrasonic Water-in-Diesel Emulsion (WiDE) Fuel System for Low-Emission Diesel Engine Combustion

Water-in-diesel emulsion (WiDE) fuel is a promising alternative fuel capable of reducing nitrogen oxides (NOX) and particulate matter (PM) in diesel engine exhaust while simultaneously preserving combustion efficiency of the engine. However, the instability of WiDE fuel—and the high costs of production and transportation—hinder its commercialization and widespread use. An on-board ultrasonic WiDE fuel supply system is proposed as a solution to this challenge. This system allows diesel fuel and water to be continuously emulsified on-board a diesel vehicle. Diesel fuel and water, stored in individual reservoirs, are conveyed in specific ratios to an in-line mixing chamber and are rapidly homogenized by ultrasonic cavitation before entering the fuel injectors. The produced emulsion fuel is then supplied to the engine. A proof-of-concept study was conducted to compare exhaust emissions between emulsion fuels and conventional fuels. Open-flame combustion experiments were conducted using a lab-scale burner to test the system with both diesel and biodiesel fuels. Unique optical diagnostics and image-processing techniques were used to estimate PM emission levels. Results showed a reduction of PM with the use of the on-board WiDE system compared to traditional diesel fuels. PM emissions from biodiesel fuel were reduced by 58% when water-in-biodiesel emulsion was combusted with 2% water. Additionally, a PM emission reduction of 35% was achieved through emulsification of diesel fuel with 2% water. This prototype demonstrates the potential for the on-board WiDE fuel supply concept to both overcome the traditional barriers hindering the commercialization of WiDE fuel and preserve its low-emission and superior combustion efficiency characteristics.

Indoor levels of black carbon and particulate matters in relation to cooking activities using different cook stove-fuels in rural Nepal

In Nepal, majority of households still burn solid fuels in inefficient cook stoves inside poorly ventilated kitchens, which results in very high levels of indoor pollutants, including black carbon (BC). Previous studies have not yet reported BC concentrations in typical kitchen configurations in rural Nepal. In this study, fine particulate matter (PM) and BC concentrations were monitored continuously inside two types of kitchens (separated from and attached to the main house) under actual cooking practices. Prior to monitoring of pollutants, a field survey was conducted to gain insight into the types of kitchens, cook stoves and fuels used. Indoor PM and BC concentrations were monitored using biomass fuels in traditional cook stoves (TC) and improved cook stoves (ICS). Clear diurnal variations of the pollutants were observed in both kitchens, with the highest concentrations during cooking times. BC and PM concentrations during cooking and non-cooking periods demonstrated clear reductions in the concentrations during non-cooking periods. It was observed that the concentrations rose steeply during the first half hour of cooking, then decreased slightly and finally leveled off to the non-cooking period concentrations. 24-hour average indoor PM concentrations in both kitchens frequently exceeded Nepal's indoor air quality standards and the WHO PM2.5 guidelines, by a factor of ~8 to ~28. We found that the specific type of ICS used in this study, a commonly used ICS in Nepal and other developing countries might help in PM emission reductions but not necessarily BC emission reduction.

Mechanisms of ultrafine particle formation during coal combustion in a new swirl modification device

A new swirl combustion device was designed and enhanced, which realized the utilization of steel slag, achieved highly efficient and clean coal combustion, and simultaneously realized a fully elemental utilization of coal. The distribution laws of different sized particulate matter (PM) emission and the enrichment laws of elements in particles under diverse conditions (such as various excess air coefficients and different coal ratios) were systematically studied. The enrichments of PM under both non-staged and fuel-staged conditions were also investigated. The results indicated that fuel-staged combustion is more helpful in reducing PM emissions than non-staged combustion, and a suitable coal ratio is also beneficial for reducing PM emissions. The melted liquid steel slag drop captured the fly ash produced from pulverized combustion, thus reducing PM emission. The alkali metal elements (K, Na, and Mg), the trace elements (As and Ti), and S have an obvious enrichment tendency in PM1 and PM2.5. A different coal ratio under fuel-staged combustion has a significant influence on the enrichment of Al, Si, Ca, and Fe in PM1, whereas in PM2.5, PM4, and PM10, the effect of different coal ratios on the enrichment of each element is slight.

Effects of multiple injection strategies on gaseous emissions and particle size distribution in a two-stroke compression-ignition engine operating with the gasoline partially premixed combustion concept

In order to improve performance of internal combustion engines and meet the requirements of the new pollutant emission regulations, advanced combustion strategies have been investigated. The newly designed partially premixed combustion concept has demonstrated its potential for reducing NOx and particulate matter emissions combined with high indicated efficiencies while still retaining proper control over combustion process by using different injection strategies. In this study, parametric variations of injection pressure, second injection and third injection timings were experimentally performed to analyze the effect of the injection strategy over the air/fuel mixture process and its consequent impact on gaseous compound emissions and particulate matter emissions including its size distribution. Tests were carried out on a newly designed two-stroke high-speed direct injection compression-ignition engine operating with the partially premixed combustion concept using 95 research octane number gasoline fuel. A scanning particle sizer was used to measure the particles size distribution and the HORIBA 7100DEGR gas analyzer system to determine gaseous emissions. Three different steady-state operation modes in terms of indicated mean effective pressure and engine speed were investigated: 3.5 bar indicated mean effective pressure and 2000 r/min, 5.5 bar indicated mean effective pressure and 2000 r/min, and 5.5 bar indicated mean effective pressure and 2500 r/min. The experimental results confirm how the use of an adequate injection strategy is indispensable to obtain low exhaust emissions values and a balance between the different pollutants. With the increase in the injection pressure and delay in the second injection, it was possible to obtain a trade-off between NOx and particulate matter emission reduction, while there was an increase in hydrocarbon and carbon monoxide emissions under these conditions. In addition, the experiments showed an increase in particle number emissions and a progressive shift in the particles size distribution toward larger sizes, increasing the accumulation-mode particles and reducing the nucleation-mode particles with the decrease in the injection pressure and delay in the third injection.

Numerical and physical assessment of control measures to mitigate fugitive dust emissions from harbor activities

In recent years, the industrial demand for petcoke—a solid residue derived from the refinement of crude oil—has been growing due to its low cost. The use of petcoke is causing environmental concern associated with its high level of contaminants and air pollutant emissions, mainly particulate matter (PM). Given the impact of petcoke on the environment and human health, increased attention has been given to its production, storage, transportation, and application processes. The main goal of this work was to assess the effectiveness of placing a barrier to reduce PM emissions from petcoke in a harbor area. The Port of Aveiro, Portugal, was used as case study. Firstly, wind tunnel experiments were performed for different types of barrier to (i) assess the effect on PM emissions of different types of barriers, namely solid, porous, and raised porous barriers; (ii) determine the optimal size and location of the barrier to achieve maximum reduction of PM emissions; and (iii) estimate the impact of placing such barrier in the attenuation of petcoke emissions over the harbor area. Secondly, the numerical model VADIS (pollutant DISpersion in the atmosphere under VAriable wind conditions) was run to evaluate the effect of implementing the barrier on the local air quality. Results showed that the best solution would be the implementation of two solid barriers: a main barrier of 109 m length plus a second barrier of 30 m length. This measure produced the best results in terms of reduction of the dispersion of particulate matter from the petcoke stockpile and minimization of the PM concentrations in the harbor surrounding area.

Optimization of Secondary Air Injection in a Wood-Burning Cookstove: An Experimental Study.

Nearly 40% of the world's population regularly cooks on inefficient biomass stoves that emit harmful airborne pollutants, such as particulate matter (PM). Secondary air injection can significantly reduce PM mass emissions to mitigate the health and climate impacts associated with biomass cookstoves. However, secondary air injection can also increase the number of ultrafine particles emitted, which may be more harmful to health. This research investigates the effect of secondary air injection on the mass and size distribution of PM emitted during solid biomass combustion. An experimental wood-burning cookstove platform and parametric testing approach are presented to identify and optimize secondary air injection parameters that reduce PM and other harmful pollutants. Size-resolved measurements of PM emissions were collected and analyzed as a function of parametric stove design settings. The results show that PM emissions are highly sensitive to secondary air injection flow rate and velocity. Although increasing turbulent mixing (through increased velocity) can promote more complete combustion, increasing the total flow rate of secondary air may cause localized flame quenching that increases particle emissions. Therefore, biomass cookstoves that implement secondary air injection should be carefully optimized and validated to ensure that PM emission reductions are achieved throughout the particle size range.

Experimental investigation on the performance and emissions characteristics of ethanol/diesel dual-fuel combustion

The diesel compression ignition (CI) engine has higher durability and thermal efficiency than the gasoline spark ignition (SI) engine. However, the high levels of nitrogen oxides (NOx) and particulate matter (PM) emissions are major problems of diesel engines due to the auto-ignition of heterogeneous mixtures. The dual-fuel combustion concept could be solution to environmental concerns. Dual-fuel combustion can be implemented by substituting some of the diesel fuel with high-volatility fuels, such as gasoline and natural gas. The premixed mixture condition can be improved to diminish localized rich and stoichiometric regions. Notably, ethanol has greater potential to reduce PM emissions because it is highly volatile and readily oxidized.For these reasons, in this research, the effects of varying the ethanol substitution ratio on engine performance and emissions under the dual-fuel combustion condition were experimentally investigated under various load conditions. The test engine was a heavy-duty single-cylinder diesel engine with two direct injectors. Engine speed was fixed at 1000 rpm and the load condition was varied for an indicated mean effective pressure (IMEP) ranging from 0.2 to 0.8 MPa. The ratio of ethanol to the total input energy was controlled from zero to nearly 50% of the input energy. The NOx and PM emissions decreased with increasing ethanol substitution and the mean size of the PM emissions decreased. For the mid-load condition (IMEP 0.6 MPa), the substitution was increased to 63%, but for low and high loads, higher ethanol fractions could not be used because of insufficient ignition energy at low loads and sharp increment of the in-cylinder pressure under high loads.

Impact of primary and secondary air supply intensity in stove on emissions of size-segregated particulate matter and carbonaceous aerosols from apple tree wood burning

In order to assess emission factors (EF) more accurately from household biomass burning, a series of laboratory-controlled apple tree wood burning tests were conducted to measure the EFs of size-segregated particulate matter (PM) and carbonaceous aerosols. The controlled burning experiments were conducted with designed primary air (PA) and secondary air (SA) supply intensity. An optimum value of 7m3·h−1 was found for SA, resulting the highest modified combustion efficiency (92.4±2.5%) as well as the lowest EFs of PM2.5 (0.13±0.01g·MJ−1), OC (0.04±0.03g·MJ−1) and EC (0.03±0.01g·MJ−1). SA values of 7 and 10m3·h−1 resulted the lowest EFs for all the different PM sizes. In a test with PA of 6m3·h−1 and SA of 7m3·h−1, very low EFs were observed for OC1 (8.2%), OC2 (11.2%) and especially OP (Pyrolyzed OC) (0%, not detected), indicating nearly complete combustion under this air supply condition. Besides SA, higher PA was proved to have positive effects on PM and carbonaceous fraction emission reduction. For example, with a fixed SA of 1.5m3·h−1, EFs of PM2.5 decreased from 0.64 to 0.27g·MJ−1 when PA increased from 6 to 15m3·h−1 (P<0.05). Similar reductions were also observed in EFs of OC, EC and size segregated PM.

Incentive policy for reduction of emission from ships: A case study of China

Particulate matter (PM) emissions from ships in ports are a major contributor to air pollution and smog in port cities. The issue of how to reduce PM emissions has become a critical concern for port city residents and governments. This paper establishes an incentive policy to reduce PM emissions from ships in ports. Using a Panamax bulk carrier as a case study, eight alternative approaches that could be adopted by shipping companies are compared and their operational benefits are estimated. By restricting the analysis to emission control areas (ECAs), the net present value (NPV) model shows that the diesel particulate filter (DPF) is the most advantageous approach with the highest NPV, while the exhaust gas scrubber (EGS) approach is the most economically inefficient. Meanwhile, due to DPF's excellent performance in PM abatement, it is suggested that governments should prioritize the DPF approach when promoting the application of emission reduction technologies. From the perspective of social welfare, a positive social benefit of about US $20,000 will be generated over the life cycle of a ship. However, a low government pricing in China will reduce shipping companies’ operational performance as the emission control zone (ECZ) gradually expands. As a result, an appropriate subsidy scheme is necessary to encourage shipping companies to apply emission reduction technologies.

Influence of Noble Metal and Promoter Capacity in CDPF on Particulate Matter Emissions of Diesel Bus

This study investigates the influence of noble metal capacity and promoter capacity in diesel oxidation catalysts (DOC) and catalyzed diesel particulate filters (CDPF) on particulate matter (PM) emissions. Four types of exhaust aftertreatments were applied to a diesel bus engine that meets the national Ⅲ emissions regulations. On-board tests were conducted respectively. PM emissions from the engine were strongly influenced by noble metal capacity in DOC and CDPF, especially at high speeds (the total number of particles increased by 70.8% when the noble metal capacity decreased by 5 g·ft-3 at 60 km·h-1). The higher the noble metal capacity was, the lower the PM emissions became, especially for PM in nuclei mode. The lanthanide material contributed to reducing PM emissions significantly. The content of precious metals could be reduced by 25% with proper lanthanide material, while the treatment effect of exhaust particles was guaranteed. In summary, aftertreatments are not sensitive to accelerating conditions, but the purification efficiency is obviously different under decontamination conditions.

The impact of photovoltaic (PV) installations on downwind particulate matter concentrations: Results from field observations at a 550-MWAC utility-scale PV plant

ABSTRACTWith utility-scale photovoltaic (PV) projects increasingly developed in dry and dust-prone geographies with high solar insolation, there is a critical need to analyze the impacts of PV installations on the resulting particulate matter (PM) concentrations, which have environmental and health impacts. This study is the first to quantify the impact of a utility-scale PV plant on PM concentrations downwind of the project site. Background, construction, and post-construction PM2.5 and PM10 (PM with aerodynamic diameters <2.5 and <10 μm, respectively) concentration data were collected from four beta attenuation monitor (BAM) stations over 3 yr. Based on these data, the authors evaluate the hypothesis that PM emissions from land occupied by a utility-scale PV installation are reduced after project construction through a wind-shielding effect. The results show that the (1) confidence intervals of the mean PM concentrations during construction overlap with or are lower than background concentrations for three of the four BAM stations; and (2) post-construction PM2.5 and PM10 concentrations downwind of the PV installation are significantly lower than the background concentrations at three of the four BAM stations. At the fourth BAM station, downwind post-construction PM2.5 and PM10 concentrations increased marginally by 5.7% and 2.6% of the 24-hr ambient air quality standards defined by the U.S. Environmental Protection Agency, respectively, when compared with background concentrations, with the PM2.5 increase being statistically insignificant. This increase may be due to vehicular emissions from an access road near the southwest corner of the site or a drainage berm near the south station. The findings demonstrate the overall environmental benefit of downwind PM emission abatement from a utility-scale PV installation in desert conditions due to wind shielding. With PM emission reductions observed within 10 months of completion of construction, post-construction monitoring of downwind PM levels may be reduced to a 1-yr period for other projects with similar soil and weather conditions.Implications: This study is the first to analyze impact of a utility photovoltaic (PV) project on downwind particulate matter (PM) concentration in desert conditions. The PM data were collected at four beta attenuation monitor stations over a 3-yr period. The post-construction PM concentrations are lower than background concentrations at three of four stations, therefore supporting the hypothesis of post-construction wind shielding from PV installations. With PM emission reductions observed within 10 months of completion of construction, postconstruction monitoring of downwind PM levels may be reduced to a 1-yr period for other PV projects with similar soil and weather conditions.