Catalytic co-gasification of glycerol/fat mixtures: A preliminary study

8th International Conference on Sustainable solid Waste ManagementIn this work, the co-gasification of treated crude glycerol and animal fat was studied using steam as the gasifying agent. Tests were performed in a downflow fixed bed reactor with a bed composed of catalyst particles of dolomite. The gasification process was studied using a mixture with 59% of glycerol, 3% of fat and 38% of water and tests were carried out at 700 ºC and 750 ºC. The producer gas was quantified and analysed by gas chromatography obtaining, for the tested temperatures, between 48% and 47% of H2, about 13% of CO, 11% of CH4 and CO2 content between 30% and 27%. The results showed that the use of dolomite as a catalyst promotes the production of a gas rich in H2 and CO2. The results also show that the gasification parameters increase with temperature having obtained at the maximum working temperature a gas production yield of 0.92 m3/kg at 750ºC, a cold gas production efficiency of 70.6% and for the carbon and hydrogen conversion efficiencies the values obtained were 58.0 % and 40.9% respectively.This work was supported by Portugal 2020 - POCI-01-0145-FEDER-024067 and Fundação para a Ciência e Tecnologia – SFRH/BD/137913/2018.N/

Estudo do comportamento térmico de esquentadores domésticos a gás

Dissertação apresentada para obtenção do grau de Mestre em Engenharia Mecânica, na Faculdade de Engenharia da Universidade do Porto, sob a orientação do Prof. Doutor Carlos Manuel Coutinho Tavares de Pinh

Effect of catalyst on the producer gas composition from co-gasification of glycerol/fat mixtures

In this work, steam reforming of crude glycerol and animal fat mixtures was studied. The tests were carried out at temperatures of 700 °C and 750 °C in a fixed bed reactor using activated alumina or dolomite particles, to evaluate the catalytic capacity of these minerals in the removal of tar from the producer gas. The gas produced was quantified and analyzed by gas chromatography, and it was concluded that its composition is greatly influenced by the bed material used. The results obtained showed that dolomite is more effective in reducing the tar content, evidencing its ability to catalyze the tar reform reactions and promoting the water-gas shift reaction. Consequently, using dolomite as a catalyst, a producer gas with 47–48 vol% in H and 27–30 vol% in CO2 was obtained, while using a bed of alumina particles, a gas with a high CO content (45–48 vol%) and lower H content (34–37 vol%) was produced.This work was supported by Portugal 2020 (POCI-01-0145-FEDER-024067) and by Multi-year financing of FCT- Fundação para a Ciência e Tecnologia, Portugal (grant UIDB/04730/2020).info:eu-repo/semantics/publishedVersio

Effect of catalyst on the producer gas composition from co-gasification of glycerol/fat mixtures

In this work, steam reforming of crude glycerol and animal fat mixtures was studied. The tests were carried out at temperatures of 700 °C and 750 °C in a fixed bed reactor using activated alumina or dolomite particles, to evaluate the catalytic capacity of these minerals in the removal of tar from the producer gas. The gas produced was quantified and analyzed by gas chromatography, and it was concluded that its composition is greatly influenced by the bed material used. The results obtained showed that dolomite is more effective in reducing the tar content, evidencing its ability to catalyze the tar reform reactions and promoting the water-gas shift reaction. Consequently, using dolomite as a catalyst, a producer gas with 47–48 vol% in H and 27–30 vol% in CO2 was obtained, while using a bed of alumina particles, a gas with a high CO content (45–48 vol%) and lower H content (34–37 vol%) was produced.This work was supported by Portugal 2020 (POCI-01-0145-FEDER-024067) and by Multi-year financing of FCT- Fundação para a Ciência e Tecnologia, Portugal (grant UIDB/04730/2020).info:eu-repo/semantics/publishedVersio

Insights on the use of wind speed vertical extrapolation methods

The present work aims to study the influence of using different methods for wind speed extrapolation in energy production calculations. A dataset of 21 meteorological masts from several landscape characteristics and locations, with at least one year of 10-minute wind speed/direction data, was used as the basis for calculations. Both the power law through estimation of wind shear coefficients, and the logarithmic-based profile using WAsP, were used as mathematical models for predicting wind shear. Wind speed extrapolation was performed either from the top-most height, using a distance method that incorporated all measurement heights, or using the function for wind shear coefficient prediction. It was found that using the logarithmicbased profile was the less reliable of all studied methods. The study showed that the most accurate method was the power law with wind shear coefficients estimated from the two upper heights closest to the extrapolation height, by wind direction sector of 30º, and the wind speeds extrapolation from the topmost height of the two. It is suggested that the use of this method reduces uncertainty in AEP estimates.info:eu-repo/semantics/publishedVersio

Co-gasification of glycerol/fat mixtures in a downflow fixed bed reactor: Preliminary results

The aim of this work was to assess the technical viability of glycerol/fat co-gasification. The gasification performance was studied in a downflow fixed bed reactor using steam as oxidizing agent. Tests were performed with a mixture of 10% of fat and 52% of water, and the effect of temperature was evaluated in the 800 oC to 950 oC range. Samples of dry gas from the gasifier were collected and analysed by gas chromatography in order to determine the CO, CO2, CH4 and H2 content. The results revealed that the co-gasification of glycerol/fat mixtures seems to be a feasible technical option. Best results of the gasification parameters were obtained at the highest tested temperature, 950 ◦C.This work was supported by Portugal 2020 [POCI-01-0145-FEDER-024067] and Fundação para a Ciência e Tecnologia [SFRH/BD/137913/2018].info:eu-repo/semantics/publishedVersio

Estudo da explosão do pó de cortiça

Dissertação apresentada para obtenção do grau de Doutor em Ciências de Engenharia, na Faculdade de Engenharia da Universidade do Porto, sob a orientação dos Professores Carlos Manuel Coutinho Tavares de Pinho e Elisa Maria Rodrigues Ramalh

Catalytic co-gasification of glycerol/fat mixtures: experimental vs thermodynamic equilibrium results

In this work, the co-gasification of treated crude glycerol and animal fat was studied using steam as the gasification agent. Tests were performed in a downflow fixed bed reactor with a bed composed of catalyst particles of dolomite. The gasification process was studied using a mixture with 59% of glycerol, 3% of fat, and 38% of water and tests were carried out at 700 °C and 750 °C. The producer gas was quantified and analyzed by gas chromatography obtaining, for the tested temperatures, between 48 and 47% of H2, about 13% of CO, 11% of CH4, and CO2 content between 30 and 27%. The results showed that the use of dolomite as a catalyst promotes the production of a gas rich in H2 and CO2. The results also show that the gasification parameters increase with temperature. Maximum values of 0.92 m3/kg for dry gas yield, 70.6% for cold gas efficiency, and 58% and 40.9% for carbon and hydrogens efficiencies were obtained. The gasification process was evaluated using the non-stoichiometric chemical equilibrium model. The results obtained showed that the real gasification process does not reach chemical equilibrium.This work was supported by Portugal 2020-POCI-01–0145-FEDER-024067 and by multi-year financing of FCT-Fundação para a Ciência e Tecnologia (grant UIDB/04730/2020).info:eu-repo/semantics/publishedVersio

Thermogravimetric analysis of high-density cork granules using isoconversional methods

In the present work thermogravimetric techniques were used to study the thermal degradation of high-density cork granules. Pyrolysis experiments were carried out for four heating ramps (10, 15, 20 and 25 °C.min−1), using nitrogen as the carrier gas. From the differential thermogravimetric (DTG) curves it was seen that degradation mainly occurs from 220 °C to 525 °C for the main components of cork (suberin, lignin, cellulose, and hemicellulose). It was also observed that for temperatures higher than 525 °C and up to 900 °C, lignin continued to decompose. Activation energies were calculated using the data obtained and the two isoconversional methods Kissinger–Akahira–Sunose (KAS) and Flynn–Wall–Ozawa (FWO). For the KAS method, and for degrees of conversion between 0.10 and 0.85, the activation energies varied between 232.2 and 353.0 kJ.mol−1. Using the FWO method and for the same degrees of conversion, the activation energies were in the range of 230.0 to 346.6 kJ.mol−1. These values agree with data provided by other authors, for different lignocellulosic biomass.The authors acknowledge “FCT – Fundação para a Ciência e Tecnologia, Portugal ” for the financial support of this work under Research Project UID/EQU/04730/2019.info:eu-repo/semantics/publishedVersio

Pyrolysis of leather wastes from the footwear industry –preliminary results

XXV ENCONTRO GALEGO-PORTUGUÉS DE QUÍMICAMost of the leather used by the footwear industry (more than 70%) is produced from skins and hides tanned with chromium sulphate [1]. The production of leather goods, especially shoes, gives rise to wastes that amount to 15 – 20% of the entry leather [2]. As an example, the European footwear industry generates between 1x105 to 2x105 tons per year of leather wastes [1]. In the last few years, various investigations have been carried out in order to find alternatives to the disposal of these residues in landfills. Several processes have been developed to treat the leather residues that include, among others, combustion, pyrolysis, chemical treatment (oxidation and hydrolysis) or direct application of the wastes [2]. Pyrolysis is the thermal degradation of wastes, in the presence of an inert atmosphere, producing a solid phase (biochar), a liquid phase (bio-oil) and a gas phase composed mainly of CO2, CO, CH4 and H2 [3]. Several authors have reported work on the pyrolysis of chromium tanned leather wastes [4, 5, 6]. [...]The authors would like to acknowledge ANI for the support of the Project FAMEST 24529 by Portugal 2020 Programme.info:eu-repo/semantics/publishedVersio