Browsing by Subject "PM10"

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  • Zhang, Yongwen; Chen, Dean; Fan, Jingfang; Havlin, Shlomo; Chen, Xiaosong (2018)
    Air pollution has become a major issue and caused widespread environmental and health problems. Aerosols or particulate matters are an important component of the atmosphere and can transport under complex meteorological conditions. Based on the data of PM2.5 observations, we develop a network approach to study and quantify their spreading and diffusion patterns. We calculate cross-correlation functions of the time lag between sites within different seasons. The probability distribution of correlation changes with season. It is found that the probability distributions in four seasons can be scaled into one scaling function with averages and standard deviations of correlation. This seasonal scaling behavior indicates that there is the same mechanism behind correlations of PM2.5 concentration in different seasons. Further, the weighted degrees reveal the strongest correlations of PM2.5 concentration in winter and in the North China Plain for the positive correlation pattern that is mainly caused by the transport of PM2.5. These directional degrees show net influences of PM2.5 along Gobi and inner Mongolia, the North China Plain, Central China, and Yangtze River Delta. The negative correlation pattern could be related to the large-scale atmospheric waves. Copyright (C) EPLA, 2018
  • Kupiainen, K.; Tervahattu, H.; Räisänen, M. (Elsevier Science B.V., 2003)
    Traffic causes enhanced PM10 resuspension especially during spring in the US, Japan, Norway, Sweden and Finland, among other countries. The springtime PM10 consists primarily of mineral matter from tyre-induced paved road surface wear and traction sand. In some countries, the majority of vehicles are equipped with studded tyres to enhance traction, which additionally increases road surface wear. Because the traction sand and the mineral matter from the pavement aggregate can have a similar mineralogical composition, it has been difficult to determine the source of the mineral fraction in the PM10. In this study, homogenous traction sand and pavement aggregate with different mineralogical compositions were chosen to determine the sources of PM10 particles by single particle analysis (SEMyEDX). This study was conducted in a test facility, which made it possible to rule out dust contributions from other sources. The ambient PM10 concentrations were higher when traction sand was used, regardless of whether the tyres were studded or not. Surprisingly, the use of traction sand greatly increased the number of the particles originating from the pavement. It was concluded that sand must contribute to pavement wear. This phenomenon is called the sandpaper effect. An understanding of this is important to reduce harmful effects of springtime road dust in practical winter maintenance of urban roads.
  • Ritola, Roosa; Kulovuori, Sami; Stojiljkovic, Ana; Karvosenoja, Niko (Suomen ympäristökeskus, 2021)
    Suomen ympäristökeskuksen raportteja 28/2021
    Katupölyn syntyyn vaikuttavat monet tekijät, ja sen on tutkimusten mukaan osoitettu olevan pääosin mineraaliperäistä karkean kokoluokan pölyä. Ongelmaksi katupöly muodostuu silloin, kun hiukkaset päätyvät hengitysilmaan ja aiheuttavat sitä kautta viihtyvyys- ja terveyshaittoja, erityisesti kaupunkien asukkaille. Tutkimushankkeen ”Katupölyn lähteet, päästövähennyskeinot ja ilmanlaatuvaikutukset” (KALPA) tavoitteena oli selvittää katupölypitoisuuksiin vaikuttavia tekijöitä ja eri lähteiden osuuksia erilaisissa katukohteissa sekä tunnistaa lupaavampia päästövähennysmahdollisuuksia ja edesauttaa niiden käyttöönottoa. Tämä raportti käsittelee KALPA-hankkeen kolmannessa vaiheessa (KALPA3), vuosina 2019–2020, tehtyjä tutkimuksia. KALPA-hankkeen neljän ensimmäisen vuoden tulokset on aiemmin (2019) raportoitu HSY:n julkaisusarjassa. KALPA-hanke on jatkoa aiemmille REDUST- ja KAPU- katupölyhankkeille. Hankkeen toteuttajat olivat Suomen ympäristökeskus (SYKE) ja Metropolia Ammattikorkeakoulu. Hankkeessa käytettiin erilaisia metodeja katupölypäästöjen tarkasteluun. Metropolia Ammattikorkeakoulun Nuuskija-autolla mitattiin katupölypäästöjä (PM10 ja PM2,5, eli halkaisijaltaan alle 10 tai alle 2,5 mikrometrin hiukkaset) kaupunkien katuverkoilla, työmaakohteissa ja korkean nopeuden pääväyläkohteissa sekä testattiin erilaisten pesulaitteiden ja -menetelmien tehoa pölynpoistossa. Mittauksia täydennettiin toisella mittausajoneuvolla (TRAKER-menetelmään perustuva Vectra) ja Wet Dust Samplerilla (WDS) suoritetuilla mittauksilla. WDS-mittalaitteella saadaan tietoa tienpinnassa olevasta pölyvarastosta, ja sitä hyödynnettiin mm. pesulaitetestien yhteydessä. KALPA-hankkeessa aikaisemmin tehtyjen nastarengasmittausten tuloksia verrattiin yliajotestillä saatuihin renkaiden kulumatuloksiin. Lisäksi hankkeessa käytettiin NORTRIP-katupölymallia hiekoituksen ilmanlaatuvaikutuksen tarkasteluun ja katupölyn lähteiden arvioimiseen sekä havainnollistettiin nastarengasosuuden laskemisen vaikutusta ilmanlaatuun hengitettävien hiukkasten osalta. NORTRIP-mallilla laskettuja päästökertoimia käytettiin lisäksi kansallisessa FRES-mallissa, jonka avulla arvioitiin katupölyn merkittävyyttä koko Suomen tasolla. FRES-mallilla toteutetun arvion mukaan katupölypäästöt muodostivat 34 % PM10-kokonaispäästöistä ja 5,5 % PM2,5- kokonaispäästöistä Suomessa vuonna 2015.
  • Fonseca, A. S.; Maragkidou, A.; Viana, M.; Querol, X.; Hämeri, K.; de Francisco, I.; Estepa, C.; Borrell, C.; Lennikov, V.; de la Fuente, G. F. (2016)
    The ceramic industry is an industrial sector in need of significant process changes, which may benefit from innovative technologies such as laser sintering of ceramic tiles. Such innovations result in a considerable research gap within exposure assessment studies for process-generated ultrafine and nanoparticles. This study addresses this issue aiming to characterise particle formation, release mechanisms and their impact on personal exposure during a tile sintering activity in an industrial-scale pilot plant, as a follow-up of a previous study in a laboratory-scale plant. In addition, possible particle transformations in the exhaust system, the potential for particle release to the outdoor environment, and the effectiveness of the filtration system were also assessed. For this purpose, a tiered measurement strategy was conducted. The main findings evidence that nanoparticle emission patterns were strongly linked to temperature and tile chemical composition, and mainly independent of the laser treatment. Also, new particle formation (from gaseous precursors) events were detected, with nanoparticles A potential risk for nanoparticle and ultrafine particle release to the environment was also identified, despite the fact that the efficiency of the filtration system was successfully tested and evidenced a >87% efficiency in particle number concentrations removal. (C) 2016 The Authors. Published by Elsevier B.V.
  • Räisänen, M.; Kupiainen, K.; Tervahattu, H. (Springer-Verlag GmbH, 2003)
    In northern latitudes mineral dust is formed when cars use studded tyres and roads are sanded to obtain more traction on the icy surfaces. Anti-skid and asphalt aggregates with different textural, mineralogical and mechanical properties were tested with an indoor road simulator fitted with studded and friction tyres. The particle size distribution and proportions of dust from pavement and anti-skid aggregate were analyzed using SEM-EDX. The wear on the road pavement depends on the properties of the anti-skid and asphalt aggregate (particle size distribution, mechanical/physical and textural properties). Antiskid aggregates, which contain mainly hard minerals (e.g. feldspars and quartz) and which have a low resistance to fragmentation, should be used with caution as they may break more easily into smaller particles and are likely to wear the pavement. By using high-quality anti-skid aggregates it is possible to reduce the amount of urban dust.
  • Kupiainen, K.; Tervahattu, H. (Kluwer Academic Publishers, 2004)
    Springtime urban road dust forms one of the most serious problems regarding air pollution in Finland. The composition and origin of springtime dust was studied in southern Finland with two different methods. Suspended particles (PM10 and TSP) were collected with high volume particle samplers and particle deposition was collected with moss bags. The composition of the PM1.5−10 fraction was studied using individual particle analysis with SEM/EDX. The deposition in the moss bags was analysed with ICP-MS. The results showed that during the study period, approximately 10% of both PM1.5−10 particles and the deposition originated from sanding. Other sources in the springtime PM1.5−10 were e.g. asphalt aggregate or soil and combustion processes. It can be concluded that sanding produced a relatively small amount of particulate matter under the investigated circumstances.