Hydrothermal co-carbonization of sewage sludge and whey: Enhancement of product properties and potential application in agriculture

Lime-assisted hydrothermal humification and carbonization of sugar beet pulp: Unveiling the yield, quality, and phytotoxicity of products

“…The examinations were carried out in the following manner: First, the stock solutions were prepared according to the EN 12457-2 protocol (Oleszczuk et al, 2013), in which they were diluted volumetrically in six various concentrations (1, 5, 10, 50, 100, and 200 mg/L) (Griffiths et al, 2021), as illustrated in Figure 2. Subsequently, 10 samples of Daphnia magna neonates, each 24 hours old, were subjected to the examination (Petrovič et al, 2023). The hydrothermal products were exposed to the test organism for a duration ranging from 12 to 96 h while maintaining a temperature of 20 ± 1°C.…”

“…HTH products can enhance soil nutrients and microorganism activity, improving soil characteristics and promoting plant growth (Petrovič et al, 2023). Figures 9a and b show the wheat GI treated with HTH products.…”

“…In addition to increasing process costs, higher alkaline dosage alters the pH of the final product and the surface chemistry of AHAs and hydrochar, and more importantly, it creates a boundary between HTH and HTF processes (Kohzadi et al, 2023;Tkachenko et al, 2023). One of the hot topics in hydrothermal processes is the chemical properties and toxicity of hydrothermal products (AHAs and hydrochar) to aromatics (such as furans and phenols), organic acids, heavy metals, persistent free radicals, dioxins, perfluorinated chemicals, and polycyclic aromatic hydrocarbons (Marzban et al, 2023;Petrovič et al, 2023). These compounds have negative effects on seed germination and plant growth (Bona et al, 2023;Lin et al, 2024).…”

Exploring the Properties of the Torrefaction Process and Its Prospective in Treating Lignocellulosic Material

“…In addition, the liquid media (water) in the process of wet torrefaction can be replaced with some other waste liquid streams to increase sustainability and to decrease the operation costs. In one of the previous studies, sewage sludge in combination with cheese whey was successfully applied in wet torrefaction to obtain char of a high quality for various purposes [46].…”

“…Advantages: No pre-drying necessary, suitable for wet biomass, by-products in liquid form, high quality of char with lower ash content than in dry torrefaction, possible addition of catalysts to enhance process Disadvantages: Lower char yield, high energy consumption due to high-pressure operation, possible corrosion of reactors, post-drying of char is required, complicated process to implement in continuous mode Woody biomass [13] Rice husk [43] Olive oil cake [44] Miscanthus [45] Sewage sludge and cheese whey [46] Steam torrefaction…”