Industria-instalazioetako arriskuen analisia eta segurtasuna. Oinarrizko teoria

156 pAurkibidea: 1. Segurtasun-teknikak: 1.1. Lan-baldintzak eta Osasuna. 1.2. Lan-segurtasuna: kontzeptua eta definizioa. 1.3. Lan-segurtasunerako teknikak: definizioa eta aplikazioa. 2. Istripuak instalazioetan: kasu errealen azterketa: 2.1. Lan-istripuak. 2.2. Istripuen ikerketa laneko arriskuen prebentziorako teknika gisa. 2.3. Istripuen indize estatistikoak. 2.4. Istripuen jakinarazpena eta erregistroa. 3. Prozesuen arriskuen analisia: 3.1. Laneko arriskuak. 3.2. Arriskuen analisia. 3.3. Industria kimiko eta bioteknologikoaren arrisku nagusiak. 3.4. Arriskuen identifikaziorako teknikak. 4. Substantzia arriskutsuen ihesa: 4.1. Ihesak. 4.2. Likido-isurien lurrunketa. 4.3. Gasen eta lurrunen sakabanaketa atmosferan. 4.4. Zaurgarritasun-ereduak: Probit metodología. 5. Suteak eta leherketak: 5.1. Sukoitasunaren ezaugarriak. 5.2. Leherketak. 5.3. Suteak. 5.4. Leherketen eta suteen efektuetarako Probit metodología. 6. Laneko giroa. Kutsatzaile kimikoak, fisikoak eta biologikoak: 6.1. Higiene industriala. 6.2. Kutsatzaileak identifikatzea. 6.3. Kutsatzaileekiko esposizioa neurtzea. 6.4. Kutsatzaileekiko esposizioaren balorazioa. 6.5. Prebentzioa eta neurri zuzentzaileak. 7. Larrialdi-planak, ikuskapenak eta kudeaketa: 7.1. Autobabeserako planak. 7.2. Segurtasun-ikuskapenak. 7.3. Laneko Segurtasuna eta Osasuna Kudeatzeko Sistema ISO 45001

Fe/Olivine As Primary Catalyst in the Biomass Steam Gasification in a Fountain Confined Spouted Bed Reactor

The performance of Fe/olivine catalysts was tested in the continuous steam gasification of sawdust in a bench scale plant provided with a fountain confined conical spouted bed reactor at 850 degrees C. Olivine was used as catalyst support and loaded with 5 wt%Fe. The activity and stability of the catalyst was monitored by nitrogen adsorption-desorption, X-ray fluorescence spectroscopy, temperature programmed reduction, X-ray diffraction and X-ray photoelectron spectroscopy techniques, which were conducted before and after the runs. The fountain confined conical spouted bed performs well in the biomass steam gasification with primary catalysts. In fact, this reactor allows enhancing the gas-solid contact, and therefore the catalytic activity by avoiding the elutriation of fine catalyst particles. The uncatalysed efficiency of the gasification process, assessed based on the gas production and composition, H-2 production, tar concentration and composition, and carbon conversion efficiency, was consideraby improved on the Fe/olivine catalyst, with tar reduction being especially remarkable (to 10.4 g Nm(-3)). After 140 min on stream, catalyst deactivation was particularly evident, as tar concentration increased to 19.9 g Nm(-3) (90% of that without catalyst). However, Fe/olivine catalyst was still active for WGS and CH4 steam reforming reactions, with gas and H-2 productions being 1.35 Nm(3) kg(-1) and 5.44 wt%, respectively. Metal iron oxidation to Fe3O4 caused catalyst deactivation, as the reaction environment shifted from oxidizing to reducing conditions due to operational limitations.This work was carried out with financial support from the Spain's Ministries of Science, Innovation and Universities (GN1 RTI2018-098283-J-I00 GN10 (MCIU/AEI/FEDER, UE) and Science and Innovation (PID2019-107357RB-I00 (MCI/AEI/FEDER, UE), the Basque Government (IT1218-19 and KK-2020/00107), and the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 823745. The authors also thank the technical and human support provided by SGIker from UPV/EHU and European funding (ERDF and ESF

Appraisal of agroforestry biomass wastes for hydrogen production by an integrated process of fast pyrolysis and in line steam reforming

The pyrolysis and in line steam reforming of different types of representative agroforestry biomass wastes (pine wood, citrus wastes and rice husk) was performed in a two-reactor system made up of a conical spouted bed and a fluidized bed. The pyrolysis step was carried out at 500 °C, and the steam reforming at 600 °C with a space time of 20 gcatalyst min gvolatiles−1 and a steam/biomass ratio (S/B) of 4. A study was conducted on the effect that the pyrolysis volatiles composition obtained with several biomasses has on the reforming conversion, product yields and H2 production. The different composition of the pyrolysis volatiles obtained with the three biomasses studied led to differences in the initial activity and, especially, in the catalyst deactivation rate. Initial conversions higher than 99% were obtained in all cases and the H2 production obtained varied in the 6.7–11.2 wt% range, depending on the feedstock used. The stability of the catalysts decreased depending on the feedstock as follows: pine wood ≫ citrus waste > rice husk. A detailed assessment of the mechanisms of catalyst deactivation revealed that coke deposition is the main cause of catalyst decay in all the runs. However, the volatile composition derived from the pyrolysis of citrus waste and rice husk involved the formation of an encapsulating coke, which severely blocked the catalyst pores, leading to catalyst deactivation during the first minutes of reaction.his work was carried out with the financial support of the grants PID2022-140704OB-I00 and PID2022-139454OB-I00 funded by MCIU/AEI/10.13039/501100011033 and “ERDF, a way of making Europe”, the grants TED 2021-132056B–I00 and PLEC 2021-008062 funded by MCIN/AEI/10.13039/501100011033 and “European Union NextGenerationEU/PRTR”, and the grants IT1645-22 and KK-2023/00060 funded by the Basque Government. Moreover, this project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 823745

Syngas production by bio-oil steam gasification in a fountain confined conical spouted bed reactor

The combination of delocalized units for the fast pyrolysis of biomass to produce bio-oil followed by centralized units for the gasification of bio-oil appears as an economically attractive option for the full-scale production of syngas because transportation of bio-oil is less costly than that of biomass. First goal of this study lies in the validation of a bio-oil feeding device made up of a line-thermostated at 60–80 °C and a non-atomizing injector cooled by water. This injector allows feeding the crude bio-oil in continuous mode into the conical spouted bed reactor without being clogged by the pyrolytic lignin in the bio-oil. The effect of gasification temperature on gas properties, tar composition, and carbon conversion efficiency were assessed in the 800–900 °C range. The results show that temperature promotes tar reduction (from 40.7 to 12.5 g/Nm3), carbon conversion efficiency (from 91.2 to 96.3 %) and gas yield (from 1.37 to 1.85 Nm3/kg on a dry basis) as temperature is increased from 800 to 900 °C. A novel aspect of this study is the detailed characterization of the tar evolution with temperature, which, to our knowledge, is an aspect that has not been approached in the literature related to raw bio-oil gasification.This work was carried out with the financial support from Spaińs ministries of Science and Innovation (PID2019-107357RB-I00 (MCIU/AEI/FEDER, UE), TED2021-132056B-I00 (MCI/AEI/FEDER, UE) and PLE21210-008062 (European Union Next GenerationEU/PRTR)) and the Basque Government (IT1645-22). Moreover, this project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 823745

Effect of CeO2 and MgO promoters on the performance of a Ni/Al2O3 catalyst in the steam reforming of biomass pyrolysis volatiles

A Ni/Al2O3 catalyst has been modified incorporating CeO2 and MgO promoters in order to improve its performance in the steam reforming of biomass pyrolysis volatiles. Ni/Al2O3, Ni/CeO2-Al2O3 and Ni/MgO-Al2O3 catalysts have been prepared and fresh and deactivated catalysts have been characterized by N2 adsorption/ desorption, X-ray Fluorescence (XRF), Temperature Programmed Reduction (TPR), X-ray powder diffraction (XRD), Temperature Programmed Oxidation (TPO), Transmission Electron Microscopy (TEM) and a technique based on Fourier Transform Infrared Spectroscopy-Temperature Programmed Oxidation (FTIR-TPO). The results obtained revealed a similar initial activity for the three catalysts tested (conversion higher than 98%), whereas stability has been greatly improved by incorporating CeO2 as promoter, as it enhances the gasification of coke precursors. However, Ni/MgO-Al2O3 catalyst is slightly less stable than Ni/Al2O3, presumably as a result of its lower reducibility due to the formation of MgAl2O4 spinel phase. Catalysts deactivation has been associated with coke deposition, although sintering phenomenon became also evident when the Ni/CeO2-Al2O3 catalyst was tested. The coke deposited on the catalysts does not present any specific morphology, which is evidence of its amorphous structure in the three catalysts studied.This work was carried out with financial support from the Ministry of Economy and Competitiveness of the Spanish Government (CTQ2016-75535-R (AEI/FEDER, UE) and CTQ-2015-69436-R (MINECO/FEDER, UE)), Ministry of Science, Innovation and Universities of the Spanish Government (RTI2018-101678-B-I00 (MCIU/AEI/FEDER, UE)), the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 823745, and the Basque Government (IT1218-19)

Influence of reactor and condensation system design on tyre pyrolysis products yields

This study investigates the effect the pyrolysis reactor and the condensing system type have on the tyre derived oil (TDO) and DL-limonene yield, as well as benzothiazole concentration in the TDO. All the experiments were performed at 475 °C and three technologies were investigated, fixed bed reactor (FBR), bubbling fluidised bed reactor (BFBR) and conical spouted bed reactor (CSBR), with the latter being the reactor that provided the highest TDO yield (58.2 wt.%). Furthermore, the CSBR enhances DL-limonene production due to its excellent features (low residence time of volatiles and high heat and mass transfer rates), which minimize secondary cracking reactions. Moreover, in order to maximize the TDO retention efficiency and selectively reduce the concentration of certain heteroaromatic species, two types of condensation systems were evaluated: tube-andshell condenser (indirect contact) and quenching condenser (direct contact). The quenching condenser not only promoted the condensation efficiency for DL-limonene, but also reduced the concentration of benzothiazole in the collected TDO. Indeed, the direct contact between water (fed into the quencher) and the hot volatile stream favours the dissolution of some polar heteroaromatic species, thus reducing the nitrogen and sulphur content in the TDO and increasing the applicability of TDO as fuel.This research was supported by the Recycling and Economic Development Initiative of South Africa (REDISA) and the National Research Foundation (NRF). It was also financed by the Ministry of Economy and Competitiveness (CTQ2016-75535-R) and the Ministry of Science, Innovation and Universities of the Spanish Government (RTI2018-101678-B-I00), the European Regional Development Fund (ERDF), the European Commission (HORIZON H2020-MSCA RISE- 2018. Contract No. 823745), the Basque Government (IT1218-19) and the University of the Basque Country (UFI 11/39). The authors acknowledge that any opinions, findings, conclusions or recommendations expressed in this material are the authors' own, and the sponsorscannot accept any liability whatsoever in this regard

Tuning pyrolysis temperature to improve the in-line steam reforming catalyst activity and stability

This study analyzes the two-step process of biomass pyrolysis and in-line steam reforming for the production of H2. In order to evaluate the effect of the volatile composition on the commercial Ni/Al2O3 catalyst performance and stability, biomass pyrolysis step was conducted at different temperatures (500–800 °C). The analysis of the deactivated catalysts has also allowed identifying the main bio-oil compounds responsible for catalyst decay (coke precursors). Pyrolysis temperature allows modifying the composition of the volatile stream that is subsequently reformed at 600 °C. An increase in pyrolysis temperature to 800 °C improves considerably the production of both H2 and gaseous stream at the initial reaction stages, reaching values of 12.95 wt% and 2.23 Nm3 kg−1, respectively. Catalyst stability is also considerably improved when pyrolysis temperature is increased due to the lower bio-oil yield and its different composition at high temperatures. Coke was the main cause of catalyst deactivation. Besides, the nature of the coke deposited is influenced by the composition of the pyrolysis volatiles, with encapsulating coke being formed by the adsorption and subsequent condensation of all hydrocarbons (oxygenated and non-oxygenated ones) preferably at low temperatures, whereas filamentous coke is formed when the concentrations of CO and light hydrocarbons in the volatile stream are increased at 800 °C.This work was carried out with the financial support of the grants RTI2018–101678-B-I00, RTI2018–098283-J-I00 and PID2019–107357RB-I00 funded by MCIN/AEI/ 10.13039/501100011033 and “ERDF, a way of making Europe”, and the grant IT1645–22 funded by the Basque Government. Moreover, this project has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 823745

Role of temperature in the biomass steam pyrolysis in a conical spouted bed reactor

[EN] The steam pyrolysis of pinewood sawdust has been conducted in a bench scale plant provided with a conical spouted bed reactor (CSBR). This process is of uttermost relevance for the in-line valorisation of pyrolysis volatiles, specifically for their catalytic steam reforming for hydrogen production. The influence of temperature on the product yields has been analyzed in the 500-800 degrees C range. A detailed analysis of the volatile stream (condensable and non-condensable components) has been carried out by chromatographic techniques, and the char samples have been characterized by ultimate and proximate analyses, N-2 adsorption-desorption, and Scanning Electron Microscopy. A high bio-oil yield was obtained at 500 degrees C (75.4 wt%), which is evidence of the suitable features of the conical spouted bed reactor for this process. As temperature was increased, higher gas and lower liquid and char yields were obtained. Steam was fully inert at low pyrolysis temperatures (500-600 degrees C), and only had a little influence at 700 degrees C due to the low gas residence time in the conical spouted bed reactor. At 800 degrees C, the reaction mechanism was controlled by gasification reactions. The composition of the liquid fraction was considerably influenced by pyrolysis temperature, with a less oxygenated stream as temperature was increased. Thus, phenolic compounds accounted for the major fraction at low pyrolysis temperatures, whereas hydrocarbons prevailed at 800 degrees C. The char obtained in the whole temperature range can be further used as active carbon or energy source.This work was carried out with the financial support from Spain's ministries of Science, Innovation and Universities (RTI2018-101678-B-I0 0 (MCIU/AEI/FEDER, UE) and RTI2018-098283-J-I0 0 (MCIU/AEI/FEDER, UE) ) and Science and Innovation (PID2019-107357RB-I0 0 (AEI/FEDER, UE) ) and the Basque Government (IT1218-19 and KK-2020/00107) . Moreover, this project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 823745

Analysis of hydrogen production potential from waste plastics by pyrolysis and in line oxidative steam reforming

[EN] A study was carried out on the valorization of different waste plastics (HDPE, PP, PS and PE), their mixtures and biomass/HDPE mixtures by means of pyrolysis and in line oxidative steam reforming. A thermodynamic equilibrium simulation was used for determining steam reforming data, whereas previous experimental results were considered for setting the pyrolysis volatile stream composition. The adequacy of this simulation tool was validated using experimental results obtained in the pyrolysis and in line steam reforming of different plastics. The effect the most relevant process conditions, i.e., temperature, steam/plastic ratio and equivalence ratio, have on H-2 production and reaction enthalpy was evaluated. Moreover, the most suitable conditions for the oxidative steam reforming of plastics of different nature and their mixtures were determined. The results obtained are evidence of the potential interest of this novel valorization route, as H-2 productions of up to 25 wt% were obtained operating under autothermal conditions.This work was carried out with the financial support from Spain's ministries of Science, Innovation and Universities (RTI2018-098283-JI00 (MCIU/AEI/FEDER, UE)) and Science and Innovation (PID2019-107357RB-I00 (MCI/AEI/FEDER, UE)), the European Union's Horizon 2020 research and innovation programme under the Marie SklodowskaCurie grant agreement No. 823745, and the Basque Government (IT1218-19 and KK-2020/00107)