13 research outputs found
OBTENCIÓN DE BIOCARBONES Y BIOCOMBUSTIBLES MEDIANTE PIRÓLISIS DE BIOMASA RESIDUAL
Se estudia la obtención de biocarbón, biogás y biocombustibles a partir de la pirólisis de biomasa residual de madera de abeto.Peer reviewe
The GRAUTHERMIC-Tyres process for the recycling of granulated scrap tyres
[EN] The influence of thermolysis temperature (range 500–700 °C) on the products produced from granulated scrap tyres (GST) (2–6 mm Ø) in a semi-batch pilot plant that uses several fixed bed reactors in parallel (GRAUTHERMIC-Tyres® process) was examined. This pilot unit consisted of six vertical fixed bed reactors in parallel, each with a capacity of 12 kg GST. Thermolysis proceeded in a normal air atmosphere. The solid (char), liquid (tyre-derived oil [TDO]) and gaseous products generated at each temperature were characterised. The incondensable gas fraction was used to produce electricity via a gas turbine. The yields of the gas, TDO and char fractions were 15–22 wt.%, 34–46 wt.% and 39–44 wt.% respectively, values that represent major recoveries from the GST feedstock. The TDOs were mainly a mixture of aliphatic and aromatic hydrocarbons and had very high GCVs (41–43 MJ/kg), higher than those of conventional liquid fuels. A large increase was seen in the polycyclic aromatic hydrocarbon content above 550 °C. The non-condensable gases obtained had a high GCV value (64–83 MJ/Nm3), and produced 4.1–6.5 kWh electricity/g of GST in a gas turbine. The chars had a GCV of 27–28 MJ/kg, high ash (17–21 wt.%) and zinc contents, and an essentially macroporous texture with a low BET surface area (46–78 m2/g). The thermolysis of GSTs with co-generation of gases by the GRAUTHERMIC-Tyres® method would appear to be a viable means of valorising GST.This work was performed with the financial support of ENRECO 2000 Ltd.Peer reviewe
Physico-Chemical Characteristics of the Products Derived from the Thermolysis of Waste Abies alba Mill. Wood
[EN] This paper reports the physico-chemical characteristics of the products derived from the thermolysis (thermolytic distillation) of waste silver fir (Abies alba Mill.) wood at different temperatures (400℃- 600℃) in a pilot scale plant. Depending on the thermolysis temperature, the procedure yielded 45 - 53 wt% pyroligneous acid with a high water content (80 - 86 wt%) and pH ≈ 3.6. The process also produced a carbonaceous solid or biochar (23 - 26 wt%), its properties strongly dependent on the thermolysis temperature. Gases (20 - 31 wt%) were also produced; these were transformed into electrical energy via a gas turbine. The pyroligneous acid was centrifuged to isolate a subfraction composed mostly of phenols (phenol, mequinol and furfural) with a total C content of 68 - 74 wt%. The remainder was subjected to fractionated distillation at laboratory scale, and the distillate subjected to liquid-liquid extraction using diethyl ether in two stages to obtain a bio-oil composed mainly of acetic acid (≈47%), aldehydes, ketones and alcohols (≈31%), phe- nols (≈18%) and aliphatic alcohols. The characteristics of the bio-oil depended on the thermolysis temperature.Dr. O. Rodríguez is the recipient of contract JAEDoc_ 09-00121 (CSIC), co-funded under the FSE 2007-2013 Multiregional Adaptability and Employment Operational Programme. The experimental work undertaken was per- formed with the financial support of ENRECO 2000 Ltd.Peer reviewe
Characterization of Observed Sea Surface Temperature in the Tropical Atlantic: Impact of Spatial Resolution
International Geoscience and Remote Sensing Symposium (IGARSS), 16-21 July 2023, Pasadena, CA, USASea surface temperature (SST) is a key oceanic variable controlling energy fluxes, as well as several atmospheric parameters such as wind speed, air temperature, humidity and cloudiness. During the last decades, mesoscale has received much attention and the new frontier for the coming years is the understanding of sub-mesoscale dynamics and its impact on climate. In order to address this challenge, there is a need of developing high-resolution observing systems, remote sensing sensors in conjunction with in-situ observations. Some traditional climate-oriented SST observational datasets generally do not include satellite observations and are typically based on in-situ observations, prominent examples being NOAA Extended Reconstructed SST (ERSST) and Hadley Centre SST version 3 (HadSST3). Other datasets combine both, in-situ and satellites observations, like the Hadley Centre Sea Ice and Sea Surface Temperature dataset (HadISST). The main objective of this work is to characterize sea surface temperature (SST) climatology and variability in the tropical Atlantic region. For that purpose, we thoroughly compare two standard, climate-oriented datasets, HadISST (1° resolution) and ERSSTv5 (2° resolution), with the GHRSST product developed by the European Space Agency (ESA) Climate Change Initiative (CCI) (0.05° resolution). Our results show that, at grid-point level, the three datasets behave similarly on a large scale, but they show consistent differences in all seasons, with CCI distinctly displaying more expansive and larger variability in the equatorial Atlantic and also in the subtropical North Atlantic. The differences in climatology are less apparent. In particular, over the ATL3 region, CCI is systematically colder than ERSST and HadISST, and displays higher variabilityWith the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe
Membrane-based extraction with strip/organic dispersion methodologies for metals removal and recovery from wastewaters
Membrane-based extraction with strip/organic dispersion methodologies for metals removal and recovery from wastewaters
The generation of liquid effluents containing organic and inorganic residues from industries presented a potential hazardousness for environment and human health, being mandatory the elimination of these pollutants from the respective solutions containing them. In order to achieve this goal, several techniques are being used, and among them, supported liquid membranes technologies are showing their potential for their application in the removal of metals contained in liquid effluents. Supported liquid membranes are a combination between conventional polymeric membranes and solvent extraction. Several configurations are used: Flat-sheet supported liquid membranes, spiral wounds and hollow fiber modules. In order to improve their effectiveness, smart operations have been developed: pseudo-emulsion membrane based strip dispersion (PEMSD), pseudo-emulsion based hollow fiber strip dispersion (PEHFSD), hollow fiber renewal liquid membrane (HFRLM) and double strip dispersion hybrid liquid membrane (SDHLM). This paper overviewed some of these smart supported liquid membranes technologies and their applications to the treatment of metal-bearing liquid effluents. © 2012 Desalination Publications. All rights reserved.Peer Reviewe
The institutional foundation of materialism in western societies
Studies of materialism have increased in recent years, and most of these studies examine various aspects of materialism including its individual or social consequences. However, understanding, and possibly shaping, a society’s materialistic tendencies requires a more complete study of the relationship between a society’s institutional patterns and the acceptance of materialism by its members. Consequently, the current study examines five of the institutional antecedents of materialism to understand better how and why it develops as a mode of consumption within a society. More specifically, a model relating materialism and a set of institutionalized patterns of social behavior referred to as the dominant social paradigm was developed and tested in a study of seven industrial, market-based countries. The results suggest that the economic, technological, political, anthropocentric, and competition institutions making up the dominant social paradigm are all positively related to materialism. The implications of the relationship are then discussed.<br /
The Institutional Foundations of Materialism in Western Societies: A Conceptualization and Empirical Test
Diagnostic accuracy and interobserver agreement of digital single-operator cholangioscopy for indeterminate biliary strictures
Background and Aims: Digital single-operator cholangioscopy (d-SOC) with cholangioscopic biopsy sampling has shown promise in the evaluation of indeterminate biliary strictures. Some studies have suggested higher sensitivity for visual impression compared with biopsy sampling, although assessors were not blinded to previous investigations. We aimed to investigate the diagnostic accuracy and interobserver agreement (IOA) of d-SOC in the visual appraisal of biliary strictures when blinded to additional information. Methods: A multicenter, international cohort study was performed. Cholangioscopic videos in patients with a known final diagnosis were systematically scored. Pseudonymized videos were reviewed by 19 experts in 2 steps: blinded for patient history and investigations and unblinded. Results: Forty-four high-quality videos were reviewed of 19 benign and 25 malignant strictures. The sensitivity and specificity for the diagnosis of malignancy was 74.2% and 46.9% (blinded) and 72.7% and 62.5% (unblinded). Cholangioscopic certainty of a malignant diagnosis led to overdiagnosis (sensitivity, 90.6%; specificity, 33%), especially if no additional information was provided. The IOA for the presence of malignancy was fair for both assessments (Fleiss’ κ = .245 [blinded] and κ = .321 [unblended]). For individual visual features, the IOA ranged from slight to moderate for both assessments (κ = .059-.400 vs κ = .031-.452). Conclusions: This study showed low sensitivity and specificity for blinded and unblinded d-SOC video appraisal of indeterminate biliary strictures, with considerable interobserver variation. Although reaching a consensus on the optical features of biliary strictures remains important, optimizing visually directed biopsy sampling may be the most important role of cholangioscopy in biliary stricture assessment
Imaging alternatives to colonoscopy: CT colonography and colon capsule. European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastrointestinal and Abdominal Radiology (ESGAR) Guideline – Update 2020
1. ESGE/ESGAR recommend computed tomographic colonography (CTC) as the radiological examination of choice for the diagnosis of colorectal neoplasia. Strong recommendation, high quality evidence. ESGE/ESGAR do not recommend barium enema in this setting. Strong recommendation, high quality evidence. 2. ESGE/ESGAR recommend CTC, preferably the same or next day, if colonoscopy is incomplete. The timing depends on an interdisciplinary decision including endoscopic and radiological factors. Strong recommendation, low quality evidence. ESGE/ESGAR suggests that, in centers with expertise in and availability of colon capsule endoscopy (CCE), CCE preferably the same or the next day may be considered if colonoscopy is incomplete. Weak recommendation, low quality evidence. 3. When colonoscopy is contraindicated or not possible, ESGE/ESGAR recommend CTC as an acceptable and equally sensitive alternative for patients with alarm symptoms. Strong recommendation, high quality evidence. Because of lack of direct evidence, ESGE/ESGAR do not recommend CCE in this situation. Very low quality evidence. ESGE/ESGAR recommend CTC as an acceptable alternative to colonoscopy for patients with non-alarm symptoms. Strong recommendation, high quality evidence. In centers with availability, ESGE/ESGAR suggests that CCE may be considered in patients with non-alarm symptoms. Weak recommendation, low quality evidence. 4. Where there is no organized fecal immunochemical test (FIT)-based population colorectal screening program, ESGE/ESGAR recommend CTC as an option for colorectal cancer screening, providing the screenee is adequately informed about test characteristics, benefits, and risks, and depending on local service- and patient-related factors. Strong recommendation, high quality evidence. ESGE/ESGAR do not suggest CCE as a first-line screening test for colorectal cancer. Weak recommendation, low quality evidence. 5. ESGE/ESGAR recommend CTC in the case of a positive fecal occult blood test (FOBT) or FIT with incomplete or unfeasible colonoscopy, within organized population screening programs. Strong recommendation, moderate quality evidence. ESGE/ESGAR also suggest the use of CCE in this setting based on availability. Weak recommendation, moderate quality evidence. 6. ESGE/ESGAR suggest CTC with intravenous contrast medium injection for surveillance after curative-intent resection of colorectal cancer only in patients in whom colonoscopy is contraindicated or unfeasible. Weak recommendation, low quality evidence. There is insufficient evidence to recommend CCE in this setting. Very low quality evidence. 7. ESGE/ESGAR suggest CTC in patients with high risk polyps undergoing surveillance after polypectomy only when colonoscopy is unfeasible. Weak recommendation, low quality evidence. There is insufficient evidence to recommend CCE in post-polypectomy surveillance. Very low quality evidence. 8. ESGE/ESGAR recommend against CTC in patients with acute colonic inflammation and in those who have recently undergone colorectal surgery, pending a multidisciplinary evaluation. Strong recommendation, low quality evidence. 9. ESGE/ESGAR recommend referral for endoscopic polypectomy in patients with at least one polyp ≥6 mm detected at CTC or CCE. Follow-up CTC may be clinically considered for 6–9-mm CTC-detected lesions if patients do not undergo polypectomy because of patient choice, comorbidity, and/or low risk profile for advanced neoplasia. Strong recommendation, moderate quality evidence.Source and scop