| 1. |
- Jagodzińska, Katarzyna, 1990-, et al.
(författare)
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Torrefaction of Agricultural Residues: Effect of Temperature and Residence Time on the Process Products Properties
- 2020
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Ingår i: Journal of energy resources technology. - : ASME Press. - 0195-0738 .- 1528-8994. ; 142:7, s. 070908-1-070908-8
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Tidskriftsartikel (refereegranskat)abstract
- To date, few studies on the potential utilization of agricultural residue torrefaction products have been performed. Thus, torrefaction product characterization aimed at its potential utilization was performed. Wheat–barley straw pellets and wheat–rye chaff were used in the study. The impact of the torrefaction temperature (280–320 °C) on polycyclic aromatic hydrocarbons (PAHs) content in the biochar and noncondensable gas (noncondensables) composition was investigated. The impact of the torrefaction time (30–75 min) on the composition of the condensable volatiles (condensables) and their toxicity were also studied. The torrefaction process was performed in a batch-scale reactor. The PAH contents were measured using high-performance liquid chromatography (HPLC), and the noncondensables composition was measured online using a gas analyzer and then gas chromatograph with flame ionization detector (GC-FID). The condensables composition and main compound quantification were determined and quantified using gas chromatography–mass spectrometry (GC/MS). Three toxicity tests, for saltwater bacteria (Microtox® bioassay), freshwater crustaceans (Daphtoxkit F magna®), and vascular plants (Lemna sp. growth inhibition test), were performed for the condensables. The PAHs content in the biochar, regardless of the torrefaction temperature, allows them to be used in agriculture. The produced torgas shall be co-combusted with full-caloric fuel because of its low calorific value. Toxic compounds (furans and phenols) were identified in the condensable samples, and regardless of the processing time, the condensables were classified as highly toxic. Therefore, they can be used either as pesticides or as an anaerobic digestion substrate after their detoxification.
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| 2. |
- Jagodzińska, Katarzyna, 1990-, et al.
(författare)
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Torrefaction of wheat-barley straw : Composition and toxicity of torrefaction condensates
- 2019
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Ingår i: Biomass and Bioenergy. - : Elsevier. - 0961-9534 .- 1873-2909. ; :129
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Tidskriftsartikel (refereegranskat)abstract
- Until now, few studies on the valorisation of torrefaction condensable volatiles (condensates) have been performed. The composition and toxicity of torrefaction condensable volatiles determine their possible applications. Therefore, a study on the composition of wheat-barley straw torrefaction condensates, combined with toxicity tests, was performed. This analysis was mainly aimed at the utilisation of these condensates as an anaerobic digestion substrate. The torrefaction process was performed in a batch-scale reactor at temperatures from 240 °C to 320 °C. The condensates were analysed using GC/MS, and quantitative analysis was based on the calibration curves (external standard method). Toxicity tests were performed for vascular plants (Lemna sp. Growth Inhibition Test), saltwater bacteria (Microtox® bioassay) and freshwater crustaceans (Daphtoxkit F magna® survival bioassay). The condensates were classified as highly toxic for the tested organisms. Compounds that are inhibitory and/or toxic to anaerobic bacteria were detected in the samples, e.g. furfural, guaiacol, palmitic acid and oleic acid. Taking into account the condensates’ high toxicity for the tested organisms and the presence of anaerobic digestion process inhibitors, there is a significant likelihood that prior detoxification of the condensates is necessary before they can be utilised as anaerobic digestion substrates.
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| 3. |
- Wang, Shule, 1994-, et al.
(författare)
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Effect of hydrothermal carbonization pretreatment on the pyrolysis behavior of the digestate of agricultural waste : A view on kinetics and thermodynamics
- 2022
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Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947 .- 1873-3212. ; 431, s. 133881-
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Tidskriftsartikel (refereegranskat)abstract
- Anaerobic digestion is the most promising disposal methods to treat organic waste. Also, a feasible management is necessary for the resulted digestate. Hydrothermal carbonization (HTC) combination with pyrolysis could be a proper solution to use for the treatment of digestate. In this study, the effect of an HTC on the pyrolysis of the digestate of agricultural waste (AWD) was investigated, focusing on the kinetic and thermodynamic aspects. Three model-free methods, including Friedman, KAS, and OFW methods, were used to evaluate the kinetic performance of the total and pseudo pyrolytic reactions of AWD and its hydrochar. Furthermore, kinetic predictions were made to provide more information for further studies. It was found that the HTC treatment decreased the activation energy ranges of the pyrolysis of AWD from 182.9-274.43 kJ/mol to 144.59-205.20 kJ/mol by using the Friedman method. For a more thorough understanding of the effect of HTC treatment on the pyrolysis of AWD, the pyrolysis reactions of AWD and its hydrochar were divided into two pseudoreactions using the Fraser-Suzuki deconvolution method. The mean activation energy of the deduced pseudo 2 pyrolytic reaction of hydrochar was 175.64 kJ/mol, which was 28.11 kJ/mol less than that of AWD. In addition, the Delta H(double dagger )values of the pseudo 2 reactions of AWD and its hydrochar were 197.97 and 169.68 kJ/mol, respectively. The results of kinetic isothermal predictions suggested that the peak temperature for the further research and application of the pyrolysis of AWD and its hydmchar should not be lower than 450 degrees C.
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