1. Advancing energy recovery: evaluating torrefaction temperature effects on food waste properties from fruit and vegetable processingAndreja Škorjanc, Sven Gruber, Klemen Rola, Darko Goričanec, Danijela Urbancl, 2025, izvirni znanstveni članek Opis: Most organic waste from food production is still not used for energy production. From the perspective of energy production, one option is to valorise the properties of organic waste. The fruit juice industry is growing rapidly and generates large amounts of waste. One of the main wastes in food and fruit juice processing is peach pits and apple peels. The aim of this study was to analyse the influence of torrefaction temperature on the properties of food waste, namely apple peels, peach pits and pea shells, in order to improve their energy value and determine their potential for further use and valorisation as a renewable energy source. The aim was to analyse the influence of different torrefaction temperatures on the heating value (HHV), mass yield (MY) and energy yield (EY) in order to better understand the behavior of the thermal properties of individual selected samples. The torrefaction process was carried out at temperatures of 250 ◦C, 350 ◦C and 450 ◦C. The obtained biomass was compared with dried biomass. For apple peels, HHV after torrefaction was (28 kJ/kg), MY decreased by (66–34%), while EY fell by (97–83%). Peach pits, despite a higher HHV after torrefaction (18 kJ/kg), achieved low MY (38–89%) and EY (59–99%), which reduces their efficiency in biochar production. Pea peels had EY (82–97%) and a lower HHV after torrefaction (11 kJ/kg), but their high ash content limits their wider use. The results confirm that, with increasing temperature, MY and EY for all selected biomasses decrease, which is a consequence of the degradation of hemicellulose and cellulose and the loss of volatile compounds. In most cases, increasing the torrefaction temperature improved the resistance to moisture adsorption, as this is related to the thermal process that causes structural changes. The results showed that the torrefaction process improved the hydrophobic properties of the biomass samples. Temperature was seen to have a great impact on mass energy efficiency. Apple peels generally had the highest mass and energy yield. Ključne besede: torrefaction, food waste, energy from waste, higher heating value, energy potential Objavljeno v DKUM: 07.02.2025; Ogledov: 0; Prenosov: 5
Celotno besedilo (3,55 MB) |
2. Assessing energy potential and chemical composition of food waste thermodynamic conversion products: a literature reviewAndreja Škorjanc, Darko Goričanec, Danijela Urbancl, 2024, izvirni znanstveni članek Opis: This study examines the considerable volume of food waste generated annually in Slovenia, which amounted to over 143,000 tons in 2020. The analysis shows that 40% of food waste consists of edible parts, highlighting the potential for reduction through increased consumer awareness and attitudes towards food consumption. The study shows that the consumption phase contributes the most to waste food (46%), followed by primary production (25%) and processing/manufacture (24%). The study addresses various thermodynamic processes, in particular, thermal conversion methods, such as torrefaction pyrolysis and hydrothermal carbonization, which optimize energy potential by reducing the atomic ratio (H/C) and (O/C), thereby increasing calorific value and facilitating the production of solid fuels. The main results show the effectiveness of torrefaction, pyrolysis and hydrothermal carbonization (HTC) in increasing the energy potential of food waste. Ključne besede: energy, thermodynamic conversions, pyrolysis, torrefaction, hydrothermal carbonization, food waste, energy potential, chemical composition Objavljeno v DKUM: 28.08.2024; Ogledov: 53; Prenosov: 8
Celotno besedilo (591,41 KB) |
3. Food Waste to Energy through Innovative Coupling of CHP and Heat PumpJan Drofenik, Danijela Urbancl, Darko Goričanec, Zdravko Kravanja, Zorka Novak-Pintarič, 2023, izvirni znanstveni članek Opis: This paper presents the conceptual design of a technological solution for the efficient conversion of food waste into heat and power. The distribution and composition of food loss and waste at different stages of the food supply chain in Slovenia and their potential for biogas production were determined. It was found that more than 50% of food waste comes from households. Therefore, a small plant was designed to convert food waste into biogas, which was innovatively coupled with a combined heat and power (CHP) unit and a heat pump. This doubles the amount of heat generated compared to conventional cogeneration. Based on the capacity of a micro commercial CHP unit, 3330 households (about 8000 residents) would supply food waste. The heat generated could replace 5% of the natural gas used for domestic water heating. The payback period would be 7.2 years at a heat price of about 80 EUR/MWh, however, for municipalities with more than 40,000 inhabitants the payback period would be reduced to less than 3 years. The cost price of the heat generated by this system would be about 25 EUR/MWh, taking into account the government subsidy for the operation of the CHP unit. Ključne besede: food waste to energy, biogas, combined heat and power, CHP, heat pump, efficiency, conceptual design, preliminary economic assessment, sensitivity analysis Objavljeno v DKUM: 16.02.2024; Ogledov: 3257; Prenosov: 28
Celotno besedilo (19,44 MB) Gradivo ima več datotek! Več... |