Front Bioeng Biotechnol
November 2024
Introduction: Agro-industrial wastes are generated in huge amounts triggering damages to the environment and human health. Therefore, there is an urgent necessity for its revalorisation into high-value compounds, including biofuels. One such wastes is the brewer's spent grain (BSG), a by-product of the beer industry, which is produced in vast quantities worldwide.
View Article and Find Full Text PDFLithium-ion batteries (LIBs) have gained much interest in recent years because of the increasing energy demand and the relentless progression of climate change. About 30% of the manufacturing cost for LIBs is spent on cathode materials, and its level of development is lower than the negative electrode, separator diaphragm and electrolyte, therefore becoming the "controlling step". Numerous cathodic materials have been employed, LiFePO being the most relevant one mainly because of its excellent performance, as well as its rated capacity (170 mA·h·g) and practical operating voltage (3.
View Article and Find Full Text PDFStudies on the development and evolution of anaerobic digestion (AD) pretreatments are nowadays becoming widespread, due to the outstanding benefits that these processes could entail in the management of sewage sludge. Production of sewage sludge in wastewater treatment plants (WWTPs) is becoming an extremely important environmental issue. The work presented in this paper is a continuation of our previous studies with the aim of understanding and developing the advanced thermal hydrolysis (ATH) process.
View Article and Find Full Text PDFThe aim of this work was to study in depth the behavior and optimization of a novel process, called advanced thermal hydrolysis (ATH), to determine its utility as a pretreatment (sludge solubilization) or postreatment (organic matter removal) for anaerobic digestion (AD) in the sludge line of wastewater treatment plants (WWTPs). ATH is based on a thermal hydrolysis (TH) process plus hydrogen peroxide (H(2)O(2)) addition and takes advantage of a peroxidation/direct steam injection synergistic effect. On the basis of the response surface methodology (RSM) and a modified Doehlert design, an empirical second-order polynomial model was developed for the total yield of: (a) disintegration degree [DD (%)] (solubilization), (b) filtration constant [F(c) (cm(2)/min)] (dewaterability), and (c) organic matter removal (%).
View Article and Find Full Text PDFThe aim of this work is to present the application of the hydrothermal oxidation in supercritical conditions, also named supercritical water oxidation (SCWO) to the treatment of two commercial cutting fluids: Biocut and Servol. Experiments were carried out in a continuous flow system at a constant pressure of 25 MPa, using pure oxygen as oxidant in excess, and different temperatures ranging from 673 to 773 K. Both semi-synthetic cutting fluids are a mixture of several compounds so the efficiency of the oxidation process was followed in terms of the reduction in chemical oxygen demand (COD) and total organic carbon (TOC).
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