Papers by Ilona Sarvari Horvath
Water Research, Oct 1, 2019
Frontiers in Microbiology, Jan 28, 2021
Biofuel research journal, Dec 1, 2015
European Biomass Conference and Exhibition Proceedings, 2016
In Victoria, Australia, organic waste makes up approximately 50% of the average household municip... more In Victoria, Australia, organic waste makes up approximately 50% of the average household municipal solid waste. All organic matter is a potential feedstock for anaerobic digestion however there remains a large proportion that is underutilised. Garden waste (GW) is one such lignocellulosic material with a complex cellulosehemicellulose-lignin structure making it resistant to degradation. Dilute alkaline-autoclaving (A-A) pretreatment was performed on GW at various particle sizes (unground and ground <10mm) and NaOH concentrations (0.5%, 1.0%, and 2.0% w/w), in order to assess their effects on enhancing biogas production. Batch tests showed the highest methane yield (213.70 L/kg VS) was obtained from ground GW treated at 1.0% NaOH, a 214.2% increase from untreated GW. FTIR spectroscopy was used to measure cellulose total crystallinity index (TCI), with results showing a correlation between enhanced biogas yield and reduction in TCI, with TCI 1.4973 for ground 1.0% NaOH in comparison to TCI 1.9023 for untreated GW. The findings so far have shown promise for A-A pretreatment in converting GW from a waste material to a value-added resource with the potential for use as a feedstock for bioenergy production.
Journal of environmental chemical engineering, Dec 1, 2017
Renewable Energy, Jun 1, 2020
Applied Biochemistry and Biotechnology, Jun 8, 2017
Green chemistry and chemical engineering, Jun 29, 2015
Bioresource Technology, 2018
Bioengineered
Agricultural residues are constantly increasing with increased farming processes, and improper di... more Agricultural residues are constantly increasing with increased farming processes, and improper disposal is detrimental to the environment. Majority of these waste residues are rich in lignocellulose, which makes them suitable substrate for bacterial fermentation in the production of value-added products. In this study, bacterial cellulose (BC), a purer and better form of cellulose, was produced by two Komagataeibacter sp. isolated from rotten banana and kombucha drink using corncob (CC) and sugarcane bagasse (SCB) enzymatic hydrolyzate, under different fermentation conditions, that is, static, continuous, and intermittent agitation. The physicochemical and mechanical properties of the BC films were then investigated by Fourier Transformed Infrared Spectroscopy (FTIR), Thermogravimetry analysis, Field Emission Scanning Electron Microscopy (FE-SEM), and Dynamic mechanical analysis. Agitation gave a higher BC yield, with Komagataeibacter sp. CCUG73629 producing BC from CC with a dry weight of 1.6 g/L and 1.4 g/L under continuous and intermittent agitation, respectively, compared with that of 0.9 g/L in HS medium. While BC yield of dry weight up to 1.2 g/L was obtained from SCB by Komagataeibacter sp. CCUG73630 under continuous agitation compared to that of 0.3 g/L in HS medium. FTIR analysis showed BC bands associated with cellulose I, with high thermal stability. The FE-SEM analysis showed that BC fibers were highly ordered and densely packed. Although the BC produced by both strains showed similar physicochemical and morphological properties, the BC produced by the Komagataeibacter sp. CCUG73630 in CC under intermittent agitation had the best modulus of elasticity, 10.8 GPa and tensile strength, 70.9 MPa.
Biogas reactors can be utilized more efficiently when straw and food waste are digested together ... more Biogas reactors can be utilized more efficiently when straw and food waste are digested together instead of separately. In the present study, straw in the form of pellets and briquettes has been us ...
International Journal of Recycling of Organic Waste in Agriculture, 2020
Purpose Anaerobic digestion produces renewable energy, biogas, from organic residues, but also di... more Purpose Anaerobic digestion produces renewable energy, biogas, from organic residues, but also digestate, a valuable organic fertiliser. Previous studies have indicated that digestate contains ample plant available nitrogen (N), but there are also concerns about greenhouse gas (GHG) emissions after application of digestates to soil. The aim of this study was to compare digestate and undigested feedstock for fertiliser effect as well as greenhouse gas emissions during the next season. Methods Digestate and its feedstock, manure, were compared as N fertilisers for wheat. Mixing digestate with biochar before application was also tested. After harvest, soil samples were frozen and dried. Then GHG emissions immediately after a re-wetting of dry soil and after thawing of frozen soil were measured to determine emissions after a non-growing season (dry or cold). Results All N in digestate was plant available, while there was no significant N fertiliser effect of the undigested manure. N2O e...
Journal of Environmental Sciences, 2017
Bioresource Technology, 2017
Bioresource technology, 2017
In this work, a plug flow reactor was developed for continuous dry digestion processes and its ef... more In this work, a plug flow reactor was developed for continuous dry digestion processes and its efficiency was investigated using untreated manure bedded with straw at 22% total solids content. This newly developed reactor worked successfully for 230days at increasing organic loading rates of 2.8, 4.2 and 6gVS/L/d and retention times of 60, 40 and 28days, respectively. Organic loading rates up to 4.2gVS/L/d gave a better process stability, with methane yields up to 0.163LCH4/gVSadded/d which is 56% of the theoretical yield. Further increase of organic loading rate to 6gVS/L/d caused process instability with lower volatile solid removal efficiency and cellulose degradation.
Applied Biochemistry and Biotechnology, 2016
Biodegradation and Bioremediation of Polluted Systems - New Advances and Technologies, 2015
Chemical Engineering Journal, 2015
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Papers by Ilona Sarvari Horvath