Agricultural and Biosystems Engineering Publications

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Agricultural and Biosystems Engineering, Civil, Construction and Environmental Engineering, Food Science and Human Nutrition, Toxicology

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Biological and Process Engineering and Technology




Poland is the 3rd producer of mushrooms in the world. Mushroom production in Poland accounts for nearly 25% of the total production in the EU, and it is still growing. One type of waste generated during mushroom production is mushroom spent compost (MSC), with a 5:1 (MSC: mushrooms) production rate. We investigated valorizing the MSC to produce fuel via torrefaction (‘roasting’, a.k.a. low-temperature pyrolysis). Specifically, we developed models for the MSC torrefaction kinetics using thermogravimetric analyses (TGA) and the effects of torrefaction temperature (200~300 °C) and process duration time (20~60 min) on the resulting biochar (fuel) properties. The estimated activation energy value of MSC torrefaction was 22.3 kJ.mol-1. The highest higher heating value(HHV) = 17.9 was found for 280 °C (60 min torrefaction time). The temperature of torrefaction significantly (p<0.05) increased the HHVfor constant process duration. The torrefaction duration time significantly (p<0.05) increased the HHVfor 220 °C and decreased HHVfor 300 °C. The highest mass yield 98.5% was found for 220 °C (60 min), while the highest energy yield was found for 280 °C (60 min). In addition, estimations of the value (€132.3·Mg-1d.m. or 27.7 €·Mg-1w.m) and quantity of resulting biochar (from torrefied MSC with 65.3% moisture content) were made based on the 280°C (60 min) torrefaction variant, assuming the price of commercially available coal fuel. We have shown a concept for an alternative utilization of abundant biowaste (MSC). The initial economic evaluation showed that MSC torrefaction might be profitable. This research provides a basis for alternative use of an abundant biowaste and can help charting improved, sustainable mushroom production.


This is a pre-print of the article Syguła, Ewa, Jacek Koziel, and Andrzej Białowiec. "Proof-of-the-Concept of Spent Mushrooms Compost Torrefaction-Preliminary Studies of Process Kinetics and the Influence of Temperature and Duration on Calorific Value of the Biochar." Preprints (2019): 2019070212. DOI: 10.20944/preprints201907.0212.v1. Posted with permission.



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