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Incidental ultrafine particles (UFPs) constitute a key pollutant in industrial workplaces. However, characterizing their chemical properties for exposure and toxicity assessments still remains a challenge. In this work, the performance of an aerosol concentrator (Versatile Aerosol Concentration Enrichment System, VACES) was assessed to simultaneously sample UFPs on filter substrates (for chemical analysis) and as liquid suspensions (for toxicity assessment), in a high UFP concentration scenario. An industrial case study was selected where metal-containing UFPs were emitted during thermal spraying of ceramic coatings. Results evidenced the comparability of the VACES system with online monitors in terms of UFP particle mass (for concentrations up to 95 µg UFP/m3) and between filters and liquid suspensions, in terms of particle composition (for concentrations up to 1000 µg/m3). This supports the applicability of this tool for UFP collection in view of chemical and toxicological characterization for incidental UFPs. In the industrial setting evaluated, results showed that the spraying temperature was a driver of fractionation of metals between UF (, This work was funded by SIINN ERA-NET (project id: 16), the Spanish MINECO (PCIN-2015-173-C02-01) and the French agency (Region Hauts de France). The Spanish Ministry of Science and Innovation (Project CEX2018-000794-S; Severo Ochoa) and the Generalitat de Catalunya (project number: AGAUR 2017 SGR41) provided support for the indirect costs for the Institute of Environmental Assessment and Water Research (IDAEA-CSIC). We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

A sampling methodology and a mathematical data treatment were developed that enable to determine not only total suspended particulates (TSP) emitted at channeled sources but also the PM

Particle research in harbour areas typically focuses on ship (stack) or vehicular exhaust emissions, while high particle emissions may also occur from other harbour operations such as vessel refurbishment activities. The literature regarding these activities is scarce, especially in terms of particle chemical composition and toxicity.The aim of this work was to characterize the chemical composition and toxicity of particles released during vessel refit operations. Airborne particle samples were collected inside the tents where abrasion of primer and top-coat paints with mechanical abraders took place in the Mallorca shipyard (Spain), during two experimental campaigns. On-line and offline aerosol instruments were placed at different monitoring locations to measure particle mass concentration and number concentrations, particle size distribution, chemical composition, morphology and cytotoxicity. Aerosol chemical composition of PM0.25, PM2.5, PM4 and PM10 was characterized using impaction cyclones. ELPI was used to obtain a more detailed composition from 0.006 μm to 10 μm. PM2 aerosols were sampled with a Biosampler, and in vitro analysis was performed with A549 lung cells. Particle morphology was determined by TEM. The dustiness index of the powders generated was determined using the rotating drum method (EN15051-).Release of coarse, fine and ultrafine particles, including engineered nanoparticles, was evidenced during both campaigns. Aerosol composition was linked to the primer’s composition, with main tracers Ti (270 μg/m3 as mean during the daily shift), Mg (177 μg/m3) and Al (54 μg/m3) in PM10 aerosols. Different particle morphologies and tracers were observed by TEM which related to the main chemical components analyzed. On the TEM grids, particle sizes ranged between 2000nm in diameter. In addition to the coarse, fine and ultrafine particles formed incidentally and emitted during abrasion of the primer and top-coats, the presence of markedly regular nanoparticles was also detected, which seemed to be engineered (ENPs) and probably used as nano-additives in the coatings (Miller et al., 2020). The ENP detected in the shipyard samples showed characteristic triangular and hexagonal shapes, as well as other polygonal shapes, and were detected as single nanoparticles with diameters Acknowledgement: This work was carried out in the framework of project IDAEALPORT (RTI2018-098095-BC21).Reference: Miller, R. J., Adeleye, A. S., Page, H. M., Kui, L., Lenihan, H. S., & Keller, A. A. (2020). Nano and traditional copper and zinc antifouling coatings: metal release and impact on marine sessile invertebrate communities. Journal of Nanoparticle Research, 22(5). https://doi.org/10.1007/s11051-020-04875-x

A sampling methodology and a mathematical data treatment were developed that enable to determine not only total suspended particulates (TSP) emitted at channeled sources but also the PM10, PM2.5, and PM1 mass fractions (w10, w2.5, and w1) and emission factors (E.F.), using a seven-stage cascade impactor. Moreover, a chemical analysis was performed to identify the elements present in these emissions. The proposed methodology was applied to different stages of the ceramic process, including ambient temperature (milling, shaping, glazing) and medium-high-temperature (spray-drying, drying, firing, and frit melting) stages. In total, more than 100 measurements were performed (pilot scale and industrial scale), which leads to a measurement time of 1500 h. Related to the mass fractions, in general, the mean values of w10 after the fabric filters operated at high performance are high and with little dispersion (75-85%), and it is also observed that they are practically independent of the stage considered, i.e., they are not significantly dependent on the initial PSD of the stream to be treated. In the case of the fine fraction w2.5, the behavior is more complex (w2.5: 30-60%), probably because the only variable is not the cleaning system, but also the nature of the processed material. Regarding abatement measures, the use of high-efficiency cleaning systems considerably reduces the emission factors obtained for fractions PM10, PM2.5, and PM1. In reference to chemical analysis, the presence of ZrO2 and Ni in the spray-drying and pressing stages, the significant concentration of ZrO2 in the glazing stage, the presence of Pb, As, and Zn in the firing stage, and the presence of Zn, Pb, Cd, and As compounds in the frits manufacturing should all be highlighted. Nevertheless, it should be pointed out that the use of some compounds, such as cadmium and lead, has been very limited in the last years and, therefore, presumably, the presence of these elements in the emissions should have been also reduced in the same way., This study has been funded by the Ministry of Science and Technology in the framework of the National Plan for Scientific Research, Development and Technological Innovation, reference REN2003-08916-C02-01.

Respirable crystalline silica (RCS), in the form of quartz and cristobalite from occupational sources, was classified by the International Agency for Research on Cancer (IARC) as carcinogenic to humans (category 1). In addition, RCS has recently been included in the Directive (EU) 2017/2398 about carcinogens and mutagens at work. Numerous studies suggest that the toxicity of quartz is conditioned by density and distribution of surface silanol groups, and it has been widely demonstrated at lab scale that masking these silanol groups significantly reduces silica toxicity. Based on these findings, a detoxifying, wet-coating method, using organosilanes as coating agent for reactive surface silanols, was previously developed and tested at industrial scale. In the present work, a new dry-coating process (patent pending) also using organosilanes was developed and applied to detoxify quartzes from different industrial branches. Dry-coating efficiency and stability were assessed and confirmed by both in-vitro tests (lactate dehydrogenase release and alkaline comet assay) and an intratracheal instillation study in rats. Finally, industrial trials were performed by different quartz end users (elastomers, foundry, adhesives, pigments and glazes) to evaluate the technical and economic feasibility of implementing this dry-coating process at industrial scale. From the obtained results, it can be drawn that the proposed methodology seems to represent a promising strategy to significantly reduce the risk associated with the handling of RCS-bearing materials. This RCS coating approach shows enough flexibility to be adapted to different industrial processes without significantly interfering with product quality.

The ceramic tile manufacturing process consumes large amounts of energy, mainly in the firing stage. Firing usually takes place in natural gas-fuelled continuous roller kilns, the most widely used tile firing facilities worldwide, which typically exhibit low energy efficiency (generally 5 to 20%). This paper investigates the application of energy and exergy balances to an industrial roller kiln firing porcelain tiles in order to identify the most critical parameters affecting kiln energy efficiency and propose ways of improving kiln energy performance. The experimental kiln measurements and thermodynamic calculations confirmed the kiln’s low energy performance (15%). Exergy analysis showed that 83% of the total exergy input into the kiln was destroyed, only 10% of the exergy input being kept in the physico-chemical transformations of the ceramic tile composition. The main sources of irreversibilities: natural gas combustion, heat transfer in the fired tile cooling process, and heat transfer through the kiln surfaces, were identified and quantified. The study shows that waste heat (over 61%) recovery could be expected to significantly increase kiln energy performance. Finally, further measures are proposed for optimising kiln energy efficiency.

The advanced ceramic technology has been pointed out as a potentially relevant case of occupational exposure to nanoparticles (NP). Not only when nanoscale powders are being used for production, but also in the high-temperature processing of ceramic materials there is also a high potential for NP release into the workplace environment. In vitro toxicity of engineered NP (ENP) [antimony tin oxide (Sb2O3•SnO2; ATO); zirconium oxide (ZrO2)], as well as process-generated NP (PGNP), and fine particles (PGFP), was assessed in MucilAir™ cultures at air–liquid interface (ALI). Cultures were exposed during three consecutive days to varying doses of the aerosolized NP. General cytotoxicity [lactate dehydrogenase (LDH) release, WST-1 metabolization], (oxidative) DNA damage, and the levels of pro-inflammatory mediators (IL-8 and MCP-1) were assessed. Data revealed that ENP (5.56 µg ATO/cm2 and 10.98 µg ZrO2/cm2) only caused mild cytotoxicity at early timepoints (24 h), whereas cells seemed to recover quickly since no significant changes in cytotoxicity were observed at late timepoints (72 h). No meaningful effects of the ENP were observed regarding DNA damage and cytokine levels. PGFP affected cell viability at dose levels as low as ∼9 µg/cm2, which was not seen for PGNP. However, exposure to PGNP (∼4.5 µg/cm2) caused an increase in oxidative DNA damage. These results indicated that PGFP and PGNP exhibit higher toxicity potential than ENP in mass per area unit. However, the presence of a mucociliary apparatus, as it occurs in vivo as a defense mechanism, seems to considerably attenuate the observed toxic effects. Our findings highlight the potential hazard associated with exposure to incidental NP in industrial settings., The authors would like to take this opportunity to thank all institutions involved for their support to this project. The authors kindly acknowledge TM COMAS (http://www.tmcomas.com) and Keeling & Walker (https://www.keelingwalker.co.uk) for their committed cooperation. Finally, the authors would also like to acknowledge Dr. Jüergen Schnekenburger (University of Müenster, Germany) for gamma-ray sterilization of the NP stock suspensions.

The advanced ceramic technology has been pointed out as a potentially relevant case of occupational exposure to nanoparticles (NP). Not only when nanoscale powders are being used for production, but also in the high-temperature processing of ceramic materials there is also a high potential for NP release into the workplace environment.

The ceramic industry is an industrial sector of great impact in the global economy that has been benefitting from advances in materials and processing technologies. Ceramic manufacturing has a strong potential for airborne particle formation and emission, namely of ultrafine particles (UFP) and nanoparticles (NP), meaning that workers of those industries are risk of potential exposure to these particles. At present, little is known on the impact of engineered nanoparticles (ENP) on the environment and human health and no established Occupational Exposure Limits (OEL) or specific regulations to airborne nanoparticles (ANP) exposure exist raising concerns about the possible consequences of such exposure. In this paper, we provide an overview of the current knowledge on occupational exposure to NP in the ceramic industry and their impact on human health. Possible sources and exposure scenarios, a summary of the existing methods for evaluation and monitoring of ANP in the workplace environment and proposed Nano Reference Values (NRV) for different classes of NP are presented. Case studies on occupational exposure to ANP generated at different stages of the ceramic manufacturing process are described. Finally, the toxicological potential of intentional and unintentional to ANP that have been identified in the ceramic industry workplace environment is discussed based on the existing evidence from in vitro and in vivo inhalation toxicity studies., The authors would like to acknowledge the contribution of COST Action CA15129 on Diagnosis, Monitoring and Prevention of Exposure-Related Noncommunicable Diseases (DiMoPEx).

This research focuses on the potential use of fly ash (WAf) from a Chinese pulverized-coal combustion (PCC) power plant for manufacturing foam glass. The influences of fly ash properties, fly ash/recycled glass proportion in the raw materials, addition of fluxing and foaming agent, firing temperature, and residence time at the peak temperature on the final properties (apparent density, compressing strength and leachable potential of major and trace elements) of the foam specimens are investigated. The optimal foaming products were obtained consuming up to 33.3–43.3% fly ash, adding 9–11% Na2CO3 fluxing agent and 0.5% SiC foaming agent, firing at 865–915 °C during 15 min residence time at the peak temperature. The obtained fly ash-based product revealed comparable compressive strength but slightly higher densities than commercial foam glass, with low CO2 emissions and low leachable potential for environmentally relevant trace elements within the limits for inert/no-hazardous material established by the European Council Decision 2003/33/EC for land waste disposal. The large porosity of the foam glass indicates a high potential of thermal and acoustic insulation. The foaming behavior and the final properties the foam glass are strongly influenced by properties of fly ash (mainly fluxing temperature and organic C content), fly ash/recycled glass proportion in the raw materials, addition of Na2CO3 fluxing agent and SiC foaming agent, firing temperature, and residence time at the peak temperature. The low C content and high refractory character of WAf give rise to poor foaming of the specimens when only fly ash and Na2CO3 mixtures are used. The consumption of relatively high proportions of recycled glass and SiC is essential to produce foaming.

Dry and wet routes in the ceramic tile manufacturing process refer to two different technologies for preparing the raw materials for the forming stage. Both result in a granulated solid ready for use in the pressing stage, but with different characteristics. The dry route was the first to be developed. As quality standards and tile sizes increased, the wet route was developed and introduced successfully into the manufacturing process. Since 1990, the wet route has been the most used around the world to prepare ceramic tile body raw materials. The powder produced by the wet route has finer particles and higher flowability, which has allowed the production of higher quality ceramic tiles of larger sizes. However, the process uses more energy and water and, consequently, is more costly in both economic and environmental terms. New developments in dry milling and granulation systems combined with the growing awareness of environmental impacts and European Union energy policy, and successful uses of the dry route in some important tile producer countries (especially Brazil), are leading to a reconsideration of the tile production processes. In the current context, implementation of the dry route is being considered an interesting alternative for the production of ceramic tiles with lower environmental costs. This has resulted in a significant number of studies of the technology from applied research centres and machinery producers. The present paper provides an up to date technical and environmental comparison of the dry and wet routes, based on the most recent advances, to add to the debate on the use of the dry route to produce high quality ceramic tiles.

Clays are employed in a wide variety of industries such as ceramic industry, manufacture of paper, rubber, etc. In this sense, it is well known that at industrial processes in which clayey materials are used, such as ceramic industry, in order to carry out some specific stages, the wetting of clays is commonly required. Moreover, it is also long established that wetting is an appropriated measure to reduce particulate matter emissions during clays storage and handling. The present study was undertaken to assess the influence of moisture on clay dustiness because, though the complex behaviour of the clay–water system has been known since antiquity, the mechanisms involved in clay hydration and their influence on dustiness are still not well understood. To encompass a wide range of specific surface areas, three clays and a kaolin were studied. Chemical and mineralogical analysis of these four raw materials was performed and their particle size distribution, flowability, true density, plastic limit, and specific surface area were determined. Raw materials dustiness was determined using the continuous drop method. As against what might intuitively be expected, the results showed that the relationship between moisture and dustiness was quite complex and strongly related to the hydration mechanisms. In this regard, to better understand the phenomena involved in the clay hydration process, a specific methodology was developed to estimate the critical points of the clay hydration process (regarding dustiness). This methodology can be readily applied to other clays or even to materials of different nature to predict the optimum moisture and, therefore, it could be employed to propose specific measures which could entail an improvement of outdoor and indoor air quality.

Packing of raw materials in work environments is a known source of potential health impacts (respiratory, cardiovascular) due to exposure to airborne particles. This activity was selected to test different exposure and risk assessment tools, aiming to understand the effectiveness of source enclosure as a strategy to mitigate particle release. Worker exposure to particle mass and number concentrations was monitored during packing of 7 ceramic materials in 3 packing lines in different settings, with low (L), medium (M) and high (H) degrees of source enclosure. Results showed that packing lines L and M significantly increased exposure concentrations (119–609 μg m−3 respirable, 1150–4705 μg m−3 inhalable, 24,755–51,645 cm−3 particle number), while non-significant increases were detected in line H. These results evidence the effectiveness of source enclosure as a mitigation strategy, in the case of packing of ceramic materials. Total deposited particle surface area during packing ranged between 5.4 and 11.8 × 105 μm2 min−1, with particles depositing mainly in the alveoli (51–64%) followed by head airways (27–41%) and trachea bronchi (7–10%). The comparison between the results from different risk assessment tools (Stoffenmanager, ART, NanoSafer) and the actual measured exposure concentrations evidenced that all of the tools overestimated exposure concentrations, by factors of 1.5–8. Further research is necessary to bridge the current gap between measured and modelled health risk assessments., This research was founded by the Spanish MINECO (CGL2015-66777-C2-1-R, 2-R), Generalitat de Catalunya AGAUR 2017 SGR41, the Spanish Ministry of the Environment (13CAES006), and FEDER (European Regional Development Fund) “Una manera de hacer Europa”. Additional support was provided by caLIBRAte project funded by the European Union‘s Horizon 2020 research and innovation programme under grant agreement No 686239. M.C. Minguillón acknowledges the Ramón y Cajal Fellowship awarded by the Spanish Ministry of Economy, Industry and Competitiveness. The authors also acknowledge the company in which the measurements were carried out for their support. The authors declare no conflict of interest relating to the material presented in this article.

Mass balance models have proved to be effective tools for exposure prediction in occupational settings. However, they are still not extensively tested in real-world scenarios, or for particle number concentrations. An industrial scenario characterized by high emissions of unintentionally-generated nanoparticles (NP) was selected to assess the performance of a one-box model. Worker exposure to NPs due to thermal spraying was monitored, and two methods were used to calculate emission rates: the convolution theorem, and the cyclic steady state equation. Monitored concentrations ranged between 4.2 &times, 104&ndash, 2.5 &times, 105 cm&minus, 3. Estimated emission rates were comparable with both methods: 1.4 &times, 1011&ndash, 1.2 &times, 1013 min&minus, 1 (convolution) and 1.3 &times, 1012&ndash, 1.4 &times, 1 (cyclic steady state). Modeled concentrations were 1.4-6 &times, 104 cm&minus, 3 (convolution) and 1.7&ndash, 7.1 &times, 3 (cyclic steady state). Results indicated a clear underestimation of measured particle concentrations, with ratios modeled/measured between 0.2&ndash, 0.7. While both model parametrizations provided similar results on average, using convolution emission rates improved performance on a case-by-case basis. Thus, using cyclic steady state emission rates would be advisable for preliminary risk assessment, while for more precise results, the convolution theorem would be a better option. Results show that one-box models may be useful tools for preliminary risk assessment in occupational settings when room air is well mixed.

Inhalation of airborne nanoparticles is a well-known source of potentially health-hazardous occupational exposures. Effective mitigation measures are necessary to reduce exposure, but also challenging to implement due to the different characteristics of each individual emission source and industrial scenario. The present paper describes four different exposure case studies in the ceramic industry and quantifies the effectiveness of mitigation strategies implemented during: ceramic tile processing by thermal spraying, laser ablation, the use of diesel engines, and tile firing. The mitigation measures for exposure reduction were tailored to each industrial scenario. The NP removal efficiency of source enclosure (partial/full) combined with local exhaust ventilation (LEV) were quantified to range between 65 and 85% when the enclosure was partial. The efficiency reached 99% with full enclosure and vigorous ventilation (Air Change per Hour; ACH = 132 h−1). The elimination of the source was the optimal strategy to minimize exposure in the case of diesel forklifts use. The conventional ceramic kilns used intensively (>10 years) generated high NP exposure concentrations (>106/cm3). Appropriate maintenance and enhanced sealing enabled the reduction of exposure down to 52% of the initial value. It must be added that technologically advanced kilns, enabled even greater NP reductions (down to 84%), compared to the conventional ones. This proves technological improvements can lead to significant reduction of work exposures. This work evidences the need for tailored mitigation measures due to the broad variety of potential sources and activities in industrial scenarios. The quantitative efficiency rates reported here may be valuable for the adequate parametrization of exposure prediction and risk assessment models. © 2019, The authors gratefully acknowledge the collaboration of the European Ceramics Centre in Limoges. This work was carried out in the framework of the CERASAFE project (www.cerasafe.eu), with the support of SIINN ERA-NET (project id: 16), and was funded by the Spanish MINECO (PCIN-2015-173-C02-01). Partial funding from the Generalitat de Catalunya (project number: AGAUR 2017 SGR41) is also acknowledged.

Exposure to ceramic powders, which is frequent during handling operations, is known to cause adverse health effects. Finding proxy parameters to quantify exposure is useful for efficient and timely exposure assessments. Worker exposure during handling of five materials [a silica sand (SI1), three quartzes (Q1, Q2, and Q3), and a kaolin (K1)] with different particle shape (prismatic and platy) and sizes (3.4-120 μm) was assessed. Materials handling was simulated using a dry pendular mill under two different energy settings (low and high). Three repetitions of two kilos of material were carried out per material and energy conditions with a flow rate of 8-11 kg h -1 . The performance of the dustiness index as a predictor of worker exposure was evaluated correlating material's dustiness indexes (with rotating drum and continuous drop) with exposure concentrations. Significant impacts on worker exposure in terms of inhalable and respirable mass fractions were detected for all materials. Mean inhalable mass concentrations during background were always lower than 40 μg m -3 whereas during material handling under high energy settings mean concentrations were 187, 373, 243, 156, and 430 μg m -3 for SI1, Q1, Q2, Q3, and K1, respectively. Impacts were not significant with regard to particle number concentration: background particle number concentrations ranged between 10 620 and 46 421 cm -3 while during handling under high energy settings they were 20 880 - 40 498 cm -3 . Mean lung deposited surface area during background ranged between 27 and 101 μm 2 cm -3 whereas it ranged between 22 and 42 μm 2 cm -3 during materials handling. TEM images evidenced the presence of nanoparticles (≤100 nm) in the form of aggregates (300 nm-1 μm) in the worker area, and a slight reduction on mean particle size during handling was detected. Dustiness and exposure concentrations showed a high degree of correlation (R 2 = 0.77-0.97) for the materials and operating conditions assessed, suggesting that dustiness could be considered a relevant predictor for workplace exposure. Nevertheless, the relationship between dustiness and exposure is complex and should be assessed for each process, taking into account not only material behaviour but also energy settings and workplace characteristics. © The Author(s) 2018., This research was funded by the Spanish MINECO (CGL2015-66777-C2-1-R, 2-R), Generalitat de Catalunya AGAUR 2014 SGR33, the Spanish Ministry of the Environment (13CAES006) and FEDER (European Regional Development Fund) “Una manera de hacer Europa”. M.C. Minguillón acknowledges the Ramón y Cajal Fellowship awarded by the Spanish Ministry of Economy, Industry and Competitiveness. The authors also acknowledge the company MOLARIS for their support with technical information on the mill used. The authors declare no conflict of interest relating to the material presented in this article.

Modelling of particle exposure is a useful tool for preliminary exposure assessment in workplaces with low and high exposure concentrations. However, actual exposure measurements are needed to assess models reliability. Worker exposure was monitored during packing of an inorganic granulate fertilizer at industrial scale using small and big bags. Particle concentrations were modelled with one and two box models, where the emission source was estimated with the fertilizer's dustiness index. The exposure levels were used to calculate inhaled dose rates and test accuracy of the exposure modellings. The particle number concentrations were measured from worker area by using a mobility and optical particle sizer which were used to calculate surface area and mass concentrations. The concentrations in the worker area during pre-activity ranged 63,797–81,073 cm−3, 4.6 × 106 to 7.5 × 106 μm2 cm−3, and 354 to 634 μg m−3 (respirable mass fraction) and during packing 50,300 to 85,949 cm−3, 4.3 × 106 to 7.6 × 106 μm2 cm−3, and 279 to 668 μg m−3 (respirable mass fraction). Thus, the packing process did not significantly increase the exposure levels. Chemical exposure was also under control based on REACH standards. The particle surface area deposition rate in respiratory tract was up to 7.6 × 106 μm2 min−1 during packing, with 52%–61% of deposition occurring in the alveolar region. Ratios of the modelled and measured concentrations were 0.98 ± 0.19 and 0.84 ± 0.12 for small and big bags, respectively, when using the one box model, and 0.88 ± 0.25 and 0.82 ± 0.12, when using the two box model. The modelling precision improved for both models when outdoor particle concentrations were included. This study shows that exposure concentrations in a low emission industrial scenario, e.g. during packing of a fertilizer, can be predicted with a reasonable accuracy by using the concept of dustiness and mass balance models., This research was founded by the Spanish MINECO (CGL2015-66777-C2-1-R, 2-R), Generalitat de Catalunya AGAUR 2017 SGR41, the Spanish Ministry of the Environment (13CAES006), FEDER (European Regional Development Fund) “Una manera de hacer Europa” and H2020 project caLIBRAte (Work Package 7). M.C. Minguillón acknowledges the Ramón y Cajal Fellowship awarded by the Spanish Ministry of Economy, Industry and Competitiveness. The authors also acknowledge the company in which the measurements were carried out for their support. The authors declare no conflict of interest relating to the material presented in this article.

Ceramic tile manufacturing is deemed to be an energy intensive industry, mainly based on combustion processes and, therefore, subject to European policies aiming at reducing greenhouse gas emissions. The “Roadmap for moving to a competitive low-carbon economy in 2050”, approved by the European Commission, calls for sectoral strategies to reduce CO2 emissions by 20% by 2020 and by 83–87% by 2050, compared to 1990 CO2 emissions. This study included up to 17 technological alternatives and their combination, resulting in 25 technological scenarios associated to the life cycle of porcelain stoneware tiles. In this regard, a high parametrized LCA model was developed to allow for the required flexibility. The scenario analysis can be used: a) to estimate the degree of technological innovation required; b) to define and to focus strategies and; c) to devise the lines of technological development that need to be implemented in the ceramic tile manufacturing sector in the coming years. The alternatives consisted of endogenous and exogenous sectoral technologies. The technologic alternatives involved changes in product design (thickness and decoration), changes in the manufacturing process (preparation of raw material by dry or wet route, and simultaneous implementation of thermal energy efficiency techniques), and changes in the energy sources (hybrid and/or electric driers, and kilns and decarbonization of the power grid mix). It was clearly proven that the wider the scope of the Life Cycle Assessment study is, the greater eco-innovations are necessary. In all the studied scenarios, the manufacturing stage was always the most significant from the global warming point of view. Finally, regarding the achievability of EU objectives, the results of this study show that the implementation of widespread technologies suffice for fulfilling 2020 targets; nevertheless, only some limited combinations of both widespread and ambitious breakthrough technologies may achieve the 2050 reduction targets.

Purpose Porcelain stoneware tile (PST) iscurrently the ceram- ic tile of greatest commercial and innovation interest. An envi- ronmental life cycle assessment of different varieties of PST was undertaken to enable hotspots to be identified, strategies tobedefined,differencesbetweenPSTvarietiestobeevaluated andguidanceforPSTmanufacturerstobeprovidedinchoosing the Environmental Product Declaration (EPD) programme that best suited their needs according to grouping criteria. Methods Analysis of previous information allowed three main parameters (thickness, glaze content and mechanical treatment) to be identified in order to encompass all PST var- iations. Fifteen varieties of PST were thus studied. The cover- age of 1 m 2 of household floor surface with the different PST varieties for 50 years was defined as functional unit. The study sets out environmental data whose traceability was verified by independent third parties for obtaining 14 EPDs of PST under Spanish EPD programmes. Results and discussion The study presents PST inventory anal- ysis and environmental impact over the entire life cycle of the studied PST varieties. The natural gas consumed in the manufacturing stage accounted for more than 70% abiotic deple- tion – fossil fuels and global warming; electricity consumption accounted for more than 60% ozo ne layer depletion, while the electricity generated by the cogeneration systems avoided signif- icant environmental impacts in the Spanish power grid mix. The variationsinPSTthickness,amountofglazeandmechanicaltreat- ments were evaluated. The PST variety with the lowest environ- mentalimpactwastheonewiththelowestthickness,wasunglazed and had no mechanical treatments. Similarly, the PST variety with the highest environmental impact was the one with the greatest thickness, was glazed and had been mechanically treated. Conclusions The PST life cycle stage with the highest envi- ronmental impact was the manufacturing stage. The main hotspots found were production and consumption of energy and raw materials extraction. Variation in thickness was a key factor that proportionally influenced almost all studied impact categories; the quantity of glaze strongly modified abiotic de- pletion – elements and eutrophication, while the mechanical treatments contributed mainly to ozone depletion. The study of all PST varieties led to the important conclusion, against the current trend, that differences among them were found to be so significant that declaring a number of PSTs within the same EPD is not directly possible, and it needs preliminary verifi- cation to ensure compliance with the product category rule.

Atmospheric plasma spraying (APS) is a frequently used technique to produce enhanced-property coatings for different materials in the ceramic industry. This work aimed to characterise and quantify the impact of APS on workplace exposure to airborne particles, with a focus on ultrafine particles (UFPs, < 100 nm) and nanoparticles (< 50 nm). Particle number, mass concentrations, alveolar lung deposited surface area concentration, and size distributions, in the range 10 nm–20 μm were simultaneously monitored at the emission source, in the potential worker breathing zone, and in outdoor air. Different input materials (known as feedstock) were tested: (a) micron-sized powders, and (b) suspensions containing submicron- or nano-sized particles. Results evidenced significantly high UFP concentrations (up to 3.3 × 106/cm3) inside the spraying chamber, which impacted exposure concentrations in the worker area outside the spraying chamber (up to 8.3 × 105/cm3). Environmental release of UFPs was also detected (3.9 × 105/cm3, outside the exhaust tube). Engineered nanoparticle (ENP) release to workplace air was also evidenced by TEM microscopy. UFP emissions were detected during the application of both micron-sized powder and suspensions containing submicron- or nano-sized particles, thus suggesting that emissions were process- (and not material-) dependent. An effective risk prevention protocol was implemented, which resulted in a reduction of UFP exposure in the worker area. These findings demonstrate the potential risk of occupational exposure to UFPs during atmospheric plasma spraying, and raise the need for further research on UFP formation mechanisms in high-energy industrial processes. © 2017 The Authors, This project was supported by the Spanish MINECO through project PCIN-2015-173-C02-01, under the frame of SIINN, the ERA-NET for a Safe Implementation of Innovative Nanoscience and Nanotechnology, by SIINN-ERANET project CERASAFE (id.:16). Support is also acknowledged to FP7 Marie Curie ITN HEXACOMM (Nr. 315760), Generalitat de Catalunya (AGAUR SGR33), and the Spanish Ministry of the Environment (13CAES006).

International Conference Energy, Environment and Material Systems (EEMS 2017) Prolonged inhalation of crystalline silica particles has long been known to cause lung inflammation and development of the granulomatous and a fibrogenic lung disease known as silicosis . The International Agency for Research on Cancer (IARC) has classified Respirable Crystalline Silica (RCS) in the form of quartz and cristobalite from occupational sources as carcinogenic for humans (category 1) . In this regard, numerous studies suggest t hat the toxicity of quartz is conditioned by the surface chemistry of the quartz particles and by the density and abundance of silanol groups. Blocking these groups to avoid their interaction with cellular membranes would theoretically be possible in order to reduce or even to eliminate the toxic effect . In this regard, t he main contribution of the presented research is the development of detoxifying processes based on coating technologies at industrial scale, since the previous studies reported on literatu re were carried out at lab scale. The results obtained in two European projects show ed that the wet method to obtain quartz surface coatings (SILICOAT project) allows a good efficiency in inhibiting the silica toxic ity, and the preliminary results obtained in an ongoing project (SILIFE) suggest that the developed dry method to coat quartz surface is also very promising . The development of both coating technologies (wet and a dry) should allow these coating technologi es to be applied to a high variety of industrial activities in which quartz is processed. For this reason, a lot of end -users of quartz powders will be potentially benefited from a reduced risk associated to the exposure to RCS.

A wide variety of raw materials, involving more than 20 samples of quartzes, feldspars, nephelines, carbonates, dolomites, sands, zircons, and alumina, were selected and characterised. Dustiness, i.e., a materials' tendency to generate dust on handling, was determined using the continuous drop method. These raw materials were selected to encompass a wide range of particle sizes (1.6–294 µm) and true densities (2650–4680 kg/m3).The dustiness of the raw materials, i.e., their tendency to generate dust on handling, was determined using the continuous drop method. The influence of some key material parameters (particle size distribution, flowability, and specific surface area) on dustiness was assessed. In this regard, dustiness was found to be significantly affected by particle size distribution.Data analysis enabled development of a model for predicting the dustiness of the studied materials, assuming that dustiness depended on the particle fraction susceptible to emission and on the bulk material's...

The experimental measurement of fugitive emissions of particulate matter entails inherent complexity because they are usually discontinuous, of short duration, may be mobile, and are affected by weather conditions. Owing to this complexity, instead of experimental measurements, emission factors are used to inventory such emissions. Unfortunately, emission factor datasets are still very limited at present and are insufficient to identify problematic operations and appropriately select control measures. To extend these datasets, a source inversion methodology (described in Part I of this work) was applied to field campaigns in which operation-specific fugitive particulate matter emission factors were determined for several complex fugitive sources, some of which were mobile. Mobile sources were treated as a superposition of instantaneous sources. The experimental campaigns were conducted at ports (bulk solids terminals), aggregate quarries, and cement factories, encompassing powder handling operations and vehicle circulation on paved and unpaved roads. Emission factors were derived for the operations and materials involved in these scenarios and compared with those available in the emission factor compilations. Significant differences were observed between the emission factors obtained in the studied handling operations. These differences call into question the use of generic emission factors and highlight the need for more detailed studies in this field.

The exposure to respirable crystalline silica (RCS), e.g. quartz, in industrial settings can induce silicosis and may cause tumours in chronic periods. Consequently, RCS in the form of quartz and cristobalite has been classified as human lung carcinogen category 1 by the International Agency for Research on Cancer in 1997, acknowledging differences in hazardous potential depending on source as well as chemical, thermal, and mechanical history. The physico-chemical determinants of quartz toxicity are well understood and are linked to density and abundance of surface silanol groups/radicals. Hence, poly-2-vinylpyridine-N-oxide and aluminium lactate, which effectively block highly reactive silanol groups at the quartz surface, have formerly been introduced as therapeutic approaches in the occupational field. In the traditional ceramics industry, quartz-containing raw materials are indispensable for the manufacturing process, and workers are potentially at risk of developing quartz-related lung diseases. Therefore, in the present study, two organosilanes, i.e. Dynasylan® PTMO and Dynasylan® SIVO 160, were tested as preventive, covalent quartz-coating agents to render ceramics production safer without loss in product quality. Coating effectiveness and coating stability (up to 1 week) in artificial alveolar and lysosomal fluids were first analysed in vitro, using the industrially relevant quartz Q1 as RCS model, quartz DQ12 as a positive control, primary rat alveolar macrophages as cellular model system (75 µg cm−2; 4 h of incubation ± aluminium lactate to verify quartz-related effects), and lactate dehydrogenase release and DNA strand break induction (alkaline comet assay) as biological endpoints. In vitro results with coated quartz were confirmed in a 90-day intratracheal instillation study in rats with inflammatory parameters as most relevant readouts. The results of the present study indicate that in particular Dynasylan® SIVO 160 (0.2% w/w of quartz) was able to effectively and stably block toxicity of biologically active quartz species without interfering with technical process quality of certain ceramic products. In conclusion, covalent organosilane coatings of quartz might represent a promising strategy to increase workers’ safety in the traditional ceramics industry.

En la manipulación y/o procesado de materiales pulverulentos en la industria cerámica, uno de los riesgos más importantes desde el punto de vista ambiental y de higiene laboral es la generación de polvo ambiental. En este sentido, un parámetro de gran interés es el poder de emisión de polvo, que cuantifica la tendencia de los materiales pulverulentos a generar polvo cuando se manipulan. En este trabajo, para determinar el poder de emisión de polvo de una composición cerámica (mezcla de materias primas empleada para la fabricación de baldosas cerámicas) se ha empleado un método de caída continua. Este método se ha seleccionado por ser el que mejor representa las operaciones de manipulación de materiales pulverulentos que tienen lugar en el proceso de fabricación de baldosas cerámicas. Los resultados obtenidos muestran que el poder de emisión de polvo de una misma composición cerámica se modifica sustancialmente durante el proceso productivo dependiendo de su forma de presentación. En este sentido, la muestra procedente de la molienda vía seca presenta un elevado poder de emisión de polvo, pudiéndose reducir significativamente (> 75%) aplicando la humectación y la aglomeración. Los resultados obtenidos muestran que la presentación óptima desde el punto de vista de la minimización de la generación de polvo se alcanza en el proceso de atomización, llegándose a reducir el poder de emisión de polvo en más de un 95%. During the handling and/or processing of powdered materials in the ceramic industry, one of the most important risks regarding the environmental and occupational health is the potential generation of dust. In this regard, a parameter of great interest is the dustiness of the processed materials; this parameter quantifies the tendency of the powdered materials to generate dust when handled. In this study, to determine the dustiness of a ceramic raw material composition (mixture of the body raw materials), the continuous drop method has been used. This test apparatus was selected because it is considered to better simulate how ceramic materials are handled in the ceramic industry. The obtained results show that the dustiness of the same ceramic composition exhibits significant changes during the manufacturing process, depending on the presentation form. In this regard, the dry milling sample presents the highest dustiness, which can be significantly reduced (> 75%) applying the the moisturization and agglomeration. The obtained results also shown that the best presentation form, regarding the minimization of the dust generation, is achieved in the spray-drying process, where the dustiness is reduced by 95%.

A great quantity of thermal energy is consumed in ceramic tile manufacture, mainly in the firing stage. The most widely used facilities are roller kilns, fuelled by natural gas, in which more than 50% of the energy input is lost through the flue gas and cooling gas exhaust stacks. This paper presents a calculation methodology, based on certain kiln operating parameters, for quantifying the energy saving obtained in the kiln when part of the cooling gases are recovered in the firing chamber and are not exhausted into the atmosphere. Energy savings up to 17 % have been estimated in the studied case. Comparison of the theoretical results with the experimental data confirmed the validity of the proposed methodology. The study also evidenced the need to improve combustion process control, owing to the importance of the combustion process in kiln safety and energy efficiency.

Appropriate selection of construction materials plays a major role in a building's sustainable profile. The study sets out a comparative life cycle assessment of indoor flooring systems of different nature. The flooring systems consisted of coverings and, where required, bonding material and/or impact soundproofing material. The following coverings were assessed: inorganic (natural stone and ceramic tiles), polymer (carpeting and PVC), and wood-based (laminate and parquet) coverings. The life cycle assessment scope was defined cradle to cradle, i.e. product stage, transport to the construction site, installation of all construction elements, use, and valorisation by recycling, as end-of-life transition scenario towards a circular economy. In the use stage, three scenarios were defined as a function of pedestrian traffic intensity, which determined maintenance, repair, and replacement operations and frequencies. The environmental impacts of the coverings product stage were taken from previously assessed and selected Environmental Product Declarations (EPDs), as these are standardised public documents devised to provide environmental life cycle information. The method adopted in the study suggests that, though the use of EPDs as information source is interesting, erroneous conclusions may be drawn if the EPDs are not comparable and/or if the comparison is not made in the building context. The results indicate that the flooring systems with inorganic coverings performed best in the global warming, acidification, eutrophication, photochemical ozone creation, and abiotic depletion for fossil resources impact categories, whereas laminates performed best in the abiotic depletion for non-fossil resources and ozone layer depletion impact categories. The carpet flooring system performed worst in every impact category except photochemical ozone creation potential.

Following the entry into force of the IPPC directive, the activities that it affects, which include the ceramic sector, have needed to control fugitive particle emissions by implementing corrective measures that often entail significant economic costs. In the most demanding cases, the Integrated Environmental Authorisations (IEA) awarded to companies in the ceramic industry require total enclosure of the raw materials handling operations. This paper evaluates the technical, economic, and environmental feasibility of the implementation of a total enclosure or containment system as a way of reducing fugitive particle emissions, as this is considered one of the Best Available Techniques (BAT). The study was carried out on the raw materials reception, handling, and storage operations at a ceramic company that manufactures spray-dried powder granules.Tras la entrada en vigor de la Directiva de Prevención y Control Integrados de la Contaminación (Directiva IPPC) las actividades afectadas por la misma, incluidas las del sector cerámico, se han visto obligadas a controlar la emisión de partículas difusas mediante la implantación de medidas correctoras, que en muchos casos suponen un impacto económico significativo. En los casos más exigentes, las Autorizaciones Ambientales Integradas (AAIs) otorgadas a empresas del sector cerámico requieren el cerramiento total de las operaciones de gestión de materias primas. En el presente trabajo se evalúa la viabilidad técnica, económica y ambiental de la implantación de un sistema de cerramiento o confinamiento total como medida de reducción de emisiones difusas al considerarse una de las Mejores Técnicas Disponibles (MTDs). El estudio se ha realizado sobre una instalación de fabricación de gránulo atomizado considerando las operaciones de recepción, gestión y almacenamiento de materias primas.

The classification of Respirable Crystalline Silica (RCS) as carcinogenic for humans has drawn greater attention to crystalline silica exposure in the workplace in recent years, leading to recommendations by safety and health bodies in Europe and the United States for lower occupational exposure limits. In view of this new scenario, the present study examined quartz dustiness, as quartz handling is a major source of crystalline silica in the workplace. The study was conducted on test samples with different mean particle sizes, prepared from several commercial quartzes. The quartz particle samples were characterised and the influence of certain quartz particle parameters on quartz dustiness was determined. The results indicate that quartz dustiness may be significantly affected by mean particle size, specific surface area, the Hausner ratio, and fine particle content. The study shows that, in order to minimise the adverse health effects associated with the inhalation of crystalline silica, quartz dustiness may be deemed a key factor in controlling the generation of fugitive quartz emissions during quartz processing, both into the outside atmosphere (air pollution) and inside the facilities (occupational health).

Global warming combined with low carbon transition plans is threatening the future of high energy consumption industry sectors in the European Union (EU). The need to respond to environmental challenges is demonstrated by support for international level energy policies and legal requirements, such as the Kyoto Protocol which the EU supports, and increased EU-level environmental legislation and energy policies. The effect of these initiatives is gradually transforming industrial activities in the EU. However, since not all countries have adopted these policies, evaluation of their net effect needs to take account also of side-effects such as delocalization of industry activity and the legal environmental frameworks in the countries where companies have chosen to relocate. This paper analyses EU energy policy and its impact on a particular energy intensive industry, the European ceramic tile sector. The discussion in this paper is not about the purpose of EU legislation, but about its effects on a specific industry. The effect of policy on industry is not a new topic, but the question of the unwanted effects of environmental and energy policy on European industry is becoming more relevant as the struggle to achieve a post-carbon Europe increases. In focussing on a specific set of EU legislation on a particular industry this article adds to the debate by showing the negative effects of policy mechanisms. The need for a scientific evaluation of the systemic changes required for a transition to a resource-efficient, green and competitive low-carbon economy outlined in the 7th Environment Action Programme is highlighted. It is suggested that the EU should periodically re-evaluate its Emissions Trading Scheme legislation to include specific actions and a follow up system which would prevent the best performing environmental companies from delocalizing or shutting down. Comments from two anonymous reviewers are very much appreciated. Cynthia Little did the language editing of the text. This work was financially supported by the Generalitat Valenciana, project ESTIBMEIC – GV/2014/049 Socio-Technical Study on the Incorporation of Biofuels in the Energy Mix Ceramic Industry.

Water spraying and/or chemical suppressants such as salts and polymers have been suggested to reduce road dust resuspension due to their capability to increase adhesion, and therefore the effective size and weight of particles, but contrasting results have been obtained so further testing are needed. This study presents the first results of street washing and Calcium Magnesium Acetate (CMA) efficiencies at two industrial roads (paved and unpaved) in the Mediterranean region where the high solar radiation, warm climate, and scarce precipitation, may play a key role in determining the efficiency of mitigation techniques Results show that, at both sites, street washing (water only) was more effective than CMA. Street washing made observe 18% (daily basis) and >90% (first hour) reductions of kerbside PM10 concentrations for the paved and unpaved road respectively, while with CMA PM10 decrease was generally lower and with less statistical significance. his work was funded by AIRUSE LIFE+ ENV/ES/584 project. The study was also partially funded by Spanish Ministry of Environment through the Fundación Biodiversidad, with project acronym EMIDIF. The logistic support from the City Hall of L'Alcora, and the Cantera La Torreta (grupo ORIGEN MATERIALES) company is also acknoweldged. Fulvio Amato is beneficiary of the Juan de la Cierva postdoctoral grant (JCI-2012-13473). Support is acknowledged to Generalitat de Catalunya 2014 SGR33 and to AXA Research Fund.

The Spanish tile manufacturing sector has grown steadily over the years covered by the three benchmark studies, carried out in 1992, 2001, and 2007, from which data are compared in this paper. In that period, production output doubled, although since the last study was published, the situation has undergone a radical change and current production output stands at a level similar to that of 1995. Nevertheless, despite the world economic crisis, which has also severely impacted the ceramic wall and floor tile sector, it is worth noting that the sector’s environmental parameters have demonstrated a constant and positive trend, both in companies’ individual environmental performance and in the actual manufacturing processes itself. To a large extent, this situation was forced upon the sector as it had to adapt to numerous environmental regulations, which in general terms call for harsher and more stringent conditions than before. In this sense, the adoption of IPPC regulations, which affect practically the entire ceramic tile sector, and the approval of EU Directive 2003/87 establishing a scheme for greenhouse gas emission allowance trading were significant factors.El sector de fabricación de baldosas cerámicas ha crecido de forma continuada durante los años que abarcan los tres estudios cuyos datos son comparados en este informe, 1992-2001-2007, ya que la producción se ha duplicado desde el primer al último estudio, aunque si se considera el periodo del último estudio hasta la actualidad, la situación ha sufrido un cambio radical estando ahora mismo en niveles de producción similares al año 1995. No obstante, a pesar de esta crisis económica mundial en la que se ha visto arrastrado el sector cerámico, merece la pena destacar una constante evolución positiva en todos los aspectos relacionados con los temas medioambientales, tanto en aquellos aspectos relacionados con el comportamiento ambiental de las empresas como en los relacionados directamente con el propio proceso de fabricación. Esta situación en gran parte ha sido forzada por la adopción de numerosa normativa medioambiental, que en líneas generales ha supuesto un endurecimiento de la legislación existente. En este sentido merece la pena destacar la adopción de la normativa IPPC, normativa que afecta prácticamente a la totalidad del sector de baldosas cerámicas, y la aprobación de la Directiva 2003/87/CE, de comercio de derechos de emisión de gases de efecto invernadero.

A new ceramic powder preparation process, the droplet-powder granulation process (DPGP), was recently proposed for the cleaner production of ceramic tiles. The DPGP granules and resulting pressed compacts were characterized and compared with the granules and compacts obtained by spray-drying (SD) and dry granulation (G) processes in a previous paper. The results showed the feasibility of using the DPGP in the pre-firing stage of porcelain tile manufacture. This study compares the firing behaviour and fired properties of compacts pressed from three different types of granulated powders: DPGP, SD, and G and from a non-granulated powder (NG) obtained by dry milling. The evolution of compact microstructure (porosity and pore size distribution) with firing temperature was monitored and the fired compact properties (bulk density, water absorption, and stain resistance) were determined. The study shows that the DPGP improved the sintering behaviour and final properties of the resulting porcelain tiles with respect to those obtained by the G process. However, the fired compacts prepared from the DPGP powder exhibited a higher porosity and pore size compared with those of the compacts obtained from the SD granules at the same pressing pressure. The results obtained open up the possibility of manufacturing glazed porcelain tiles with a more eco-friendly process. However, the results also indicate that polished porcelain tile manufacture by the DPGP requires further research in order to improve granule characteristics, in particular green granule deformability, which is the critical factor in porcelain tile densification and vitrification during firing.

An alternative cleaner process of pressing-powder preparation, based on filter-pressing and a novel granulation method, is presented to substitute the existing spray-drying process. In the new process, about two-thirds of wet-milled slurry is filter- pressed, dried and milled into dry fine powder. The other one-third of the slurry and the as-obtained dry fine powder are spray-mixed in a tower, where the slurry droplets adsorb the dry powder to form granules which are then rolled and dried into a useable pressing-powder for tile pressing. The key stages, filter-pressing and granulation (consisting of spray-mixing and rolling treatment), are specially studied. The pressing-powder properties and pressing/firing behavior, and, energy/water consumption and pollution emission data are presented, and a comparison between the new process and the existing spray-drying process is made. This new process has been found to be feasible and provides a pressing-powder with suitable properties, together with lower energy/water consumption and pollution emission (particulate matter and CO2). En ese trabajo se presenta un proceso alternativo y más ecológico para la preparación de polvo de prensas por molienda vía húmeda de las materias primas. En este proceso la eliminación del agua de la suspensión obtenida en la etapa de molienda, en vez de realizarse por secado por atomización, se lleva a cabo en dos etapas, en una primera etapa dos tercios de esta suspensión se filtro-prensan, posteriormente se secan y molturan hasta obtener un polvo seco micronizado. Este material seco se introduce por la parte superior de una torre granuladora, en la que se pulveriza el tercio de la suspensión restante por la parte inferior, de forma que las gotas adsorben sobre su superficie las partículas secas formando gránulos, que posteriormente se compactan por rodamiento (“rolling”), y finalmente se secan hasta la humedad requerida para el prensado. En este trabajo se estudian con detalle las dos etapas clave del nuevo proceso: el filtro prensado y la granulación (mezclado por pulverización y “rolling”). Además, se describen las propiedades del polvo de prensas obtenido, el comportamiento en crudo y en la fase de cocción. Los resultados indican que el nuevo proceso desarrollado, aunque es más complejo técnicamente, es viable y permite obtener un polvo de prensas con características adecuadas para obtener baldosas de gres porcelánico, aunque requiere mayores temperaturas de cocción. El análisis del proceso indica que conlleva menores emisiones contaminantes (partículas y CO2) que el proceso de atomización tradicional, así como consumos inferiores de agua y de energía.

The manufacture of traditional ceramic products (ceramic tiles, roof tiles, and bricks) is often associated with the emission of F, Cl, and S compounds during the firing stage. According to the literature, fluorine emissions can be reduced by adding CaCO3 to the raw materials mixture used in fabricating these products. However, data available to the authors indicate that this procedure, which has been successfully applied in manufacturing structural ceramics (roof tiles and bricks), is ineffective in ceramic tile manufacture and modifies tile end properties. This paper examines the possibility of reducing such emissions by applying coatings of alkaline-earth carbonates on to the ceramic tile bottom surface to retain the acid compounds emitted during tile firing. The effectiveness of MgCO3, CaCO3, SrCO3, and BaCO3 coatings for retaining these acid emissions was studied, using the evolved gas analysis (EGA) technique with a TG-DSC-FTIR-QM instrument. The SrCO3 coating was found to provide the greatest retention, showing that SO2 and HCl were retained more efficiently than HF. The presence of fluorides, chlorides, and sulphates of Ca, Sr, and Ba was verified in the respective fired coatings, confirming the existence of chemical reactions between the emitted acid compounds and the coating materials at high temperature.

The environmental characteristics of coal gangue dumps in Yangquan (Shanxi Province, China) were investigated. The amounts of coal gangue are very high in this coal region given the large coal production. As a result, widespread spontaneous coal gangue combustion gives rise to serious environmental problems. Coal gangue (including bulk gangue and specific lithologies, such as coal, kaolinite-rich material, sandstone, carbonate minerals, and sulfide mineralizations), fired coal gangue and condensate products from gas vents were fully characterized with respect to mineralogy, chemistry and leaching potential. The mineral paragenesis of the fired coal gangue (cristobalite, mullite, hematite, trydimite, cordierite) showed that the combustion temperature could reach 1200 °C. This was also corroborated by laboratory calcination tests. During this combustion some elements such as C, Cl, F, S, N, As, Cd, Hg, Pb, Sn, Ge and Se are emitted into the atmosphere. However, condensation processes accounted for the partial trapping of gaseous emissions of As, S, N, Hg and Se. Thus, condensate mineralizations of elemental sulfur and ammonium salts enriched in Se, As and other trace elements are frequent in the gas vents. The leaching potential of trace elements in the fresh coal gangue was relatively low, but the leaching of weathered coal gangue and the gas vents condensates could give rise to environmental problems, as these materials produce acidic leachates and yield relatively high leachable levels of a number of elements. © 2008 Elsevier B.V. All rights reserved.

Despite their significant role in source apportionment analysis, studies dedicated to the identification of tracer elements of emission sources of atmospheric particulate matter based on air quality data are relatively scarce. The studies describing tracer elements of specific sources currently available in the literature mostly focus on emissions from traffic or large-scale combustion processes (e.g. power plants), but not on specific industrial processes. Furthermore, marker elements are not usually determined at receptor sites, but during emission. In our study, trace element concentrations in PM10 and PM2.5 were determined at 33 monitoring stations in Spain throughout the period 1995–2006. Industrial emissions from different forms of metallurgy (steel, stainless steel, copper, zinc), ceramic and petrochemical industries were evaluated. Results obtained at sites with no significant industrial development allowed us to define usual concentration ranges for a number of trace elements in rural and urban background environments. At industrial and traffic hotspots, average trace metal concentrations were highest, exceeding rural background levels by even one order of magnitude in the cases of Cr, Mn, Cu, Zn, As, Sn, W, V, Ni, Cs and Pb. Steel production emissions were linked to high levels of Cr, Mn, Ni, Zn, Mo, Cd, Se and Sn (and probably Pb). Copper metallurgy areas showed high levels of As, Bi, Ga and Cu. Zinc metallurgy was characterised by high levels of Zn and Cd. Glazed ceramic production areas were linked to high levels of Zn, As, Se, Zr, Cs, Tl, Li, Co and Pb. High levels of Ni and V (in association) were tracers of petrochemical plants and/or fuel-oil combustion. At one site under the influence of heavy vessel traffic these elements could be considered tracers (although not exclusively) of shipping emissions. Levels of Zn–Ba and Cu–Sb were relatively high in urban areas when compared with industrialised regions due to tyre and brake abrasion, respectively.

Data on the spatial and time (2002–2005) variation of levels of trace elements and the source attribution of these elements in the ceramic cluster of Castello (Eastern Spain) are presented and discussed. Earlier studies concluded that metal levels in PM 10 were one of the most critical parameters for attaining the EU legal requirements of the air quality standards. Levels of Li, Sc, Co, Zn, As, Se, Rb, Zr, Cd, Cs, Ce, Tl and Pb were higher than the usual range of concentration in urban areas of Spain, and some of them exceeded the concentration ranges obtained for other industrial sites in Spain. Of these elements, Zr, Zn, Pb and As (and probably Tl) may be considered as tracers of the ceramic emissions from the study area. A downward trend was observed for most of them, simultaneously, with the progressive implementation of the emission abatement techniques, especially those applied to the PM abatement of the manufacture of glaze components and the avoidance of the use of specific raw materials with high contents of impurities. At the end of the study period, the elements for which the EU sets limit or target values met the established requirements for 2013 (2005 for Pb), whereas, at the beginning of the study some elements exceeded the 2013 target values. Furthermore, a detailed discussion on the interpretation of peak concentration events and source attribution for a number of trace elements is presented. Five different sources were identified: mineral emissions (from clay use and handling), industry (mainly glaze production and use), road traffic, sea spray and the regional background influenced by a fuel oil-power plant and a petrochemical plant.

Since ceramic tile industry is an energy intensive industry, European ceramic companies are challenged to reduce their CO2 emissions in the medium and long-term. According the Roadmap for moving to a low-carbon economy in 2050 (European Commission, 2011) the objective is to achieve a reduction in CO2 emissions of between 34 % and 40 % by 2030, and between 83 % and 87 % by 2050. In the present paper we present a study on the viability of the incorporation of biofuels in the energy mix of the Spanish ceramic industry with the objective of (1) identifying the potential use of biomass resources, with a special focus of forest and agricultural biomass, in the manufacturing process of ceramic tile products; (2) identify in what part of the production process it can be introduced; and (3) calculate the reduced environmental impact from the manufacture of ceramic materials through a reduction in carbon dioxide emissions. In order to proceed we firstly present the relevant state of the art for the study of the use of biomass for the ceramic manufacturing process. We continue with the methodology for biomass resources evaluation and present relevant data on forest and agricultural biomass for the ceramic tile industry. We then present data on the evolution and actual energy demand of the ceramic tile industry to characterize its energy demand. And then we identify an opportunity for biomass use in a specific phase of the manufacture of ceramic products, estimating the savings of fossil fuels and the reduction of carbon dioxide emissions and therefore assessing the environmental impact reduction through the introduction of biomass in the manufacturing process of ceramic tile products. Keywords: biomass, ceramic tile industry, energy mix, energy transition, innovation system, sustainability, tiles. Article DOI: http://doi.org/10.15544/RD.2015.073