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The mushroom agroindustry generates a huge amount of waste from mushroom production (WMP). The composition of WMP is not standardized but differs mainly in terms of organic matter (OM) content and OM biodegradability. This makes WMP management, including anaerobic digestion (AD), a significant challenge. A potential solution could be co-digestion of WMP with municipal sewage sludge (SS), especially SS generated in small rural wastewater treatment plants (WWTPs). Therefore, this study investigated mesophilic methane production (MP) from WMP, SS, and mixtures of SS and WMP at ratios of 70:30, 50:50, and 30:70 (w/w OM). Even though the maximum cumulative MP from WMP was relatively low (approx. 60 NL/kg OM), co-digesting WMP with SS increased both MP and the methane content of the biogas: with 30%, 50%, and 70% shares of SS, MP increased almost 2, 2.5, and 3.3 times, and the methane content increased to 61%, 62%, and 64%, respectively. As the SS content was increased, the kinetic coefficients of MP and OM removal decreased (from 0.211 to 0.146 d−1 and from 0.215 to 0.152 d−1), whereas the initial rate of MP and of OM removal increased (from 12.5 to 36.8 NL/(kg OM·d) and from 0.51 kg OM/(m3·d) to 0.59 kg OM/(m3·d), respectively). The effectiveness of OM removal (EOMrem) was lowest with WMP only, at 46.6%. When the SS content of the mixtures was increased to 30%, 50%, and 70%, EOMrem also increased to 55.3%, 60.1%, and 64.9%, respectively. The relationship between maximal MP and the overall OM removed was such that both increased simultaneously. The higher values of EOMrem and, consequently, the lower final contents of OM with more effective MP indicate that the organics were degraded more efficiently. These results suggest that co-digestion may be a profitable solution for simultaneously utilizing both of these waste products, increasing the efficiency of biogas production to such an extent that it would be profitable to conduct AD on mushroom farms. This is a flexible approach that allows varying proportions of WMP and SS to be used, depending on the availability of both substrates and the energy needs of the mushroom farm. However, it should be borne in mind that a higher share of WMP results in lower gas productivity. [ABSTRACT FROM AUTHOR]

The textile industry is global, and most brands export their products to many different markets with different infrastructures, logistics, and regulations. A textile waste recovery system that works in one country may fail in another. European Union legislation (Directive (EU) 2018/851) mandates that post-consumer textile waste must be separately collected in all associated countries. This directive has also stated that, in January 2025, the rate of textile waste recycling in Europe should be increased. Local governments will be under pressure to improve the collection, sorting, and recycling of textiles. Supporting local governments could be part of a more long-term approach to managing high-value textile waste by implementing Extended Producer Responsibility, which would increase the recycling rate of textile companies. This would enable reuse of over 60% of recovered clothes, recycling into fibers of 35%, and only throwing away 5%. Today, most textile waste (85%) is disposed of as solid waste and must be disposed of through municipal or local waste management systems that either landfill or incinerate the waste. To increase reuse and recycling efficiency, textile waste should be collected and sorted according to the relevant input requirements. The dominant form of textile waste sorting is manual sorting. Sorting centers could be a future solution for intensifying the recycling of textile waste. Advances in textile waste management will require digitization processes, which will facilitate the collection, sorting, and recycling of textiles. It is very important that digitization will help to guide used products to recycling and encourage manufacturers to participate in the use and collection of product data. Currently, both the digitization of textile waste management and fiber recycling technologies are at the level of laboratory research and have not been implemented. The aim of this publication is to analyze the state of textile waste management, especially the various forms of recycling that involve a local governments and the textile industry. [ABSTRACT FROM AUTHOR]

As increasing soil organic matter is considered one of the main strategies for reducing desertification in Europe, the production and use of high-quality composts has gained importance during the last decade. It is undisputed that the quantity and quality of humic substances (HS) and their fractions, i.e. fulvic acids (FA) and humic acids (HA) in compost are considered important indicators of compost maturity and chemical stability. Other important aspects are concentrations of macro- and micronutrients and heavy metals (HMs) that are introduced to the soil with mature compost. In this light, this study assessed the detailed characteristic of compost from municipal sewage sludge. Moreover, kinetic of organic matter (OM), and nitrogen transformations, therein nitrogen loss, were analysed. OM degradation proceeded according to first-order kinetics. In the bioreactor, the rate constant of OM removal and the rate of OM removal were 0.134 d−1 and 12.6 mg/(g d.m.d), respectively. In the windrow, these constants were 5.2-fold and 16.7-fold lower, respectively. In mature compost, the concentration of HS equaled 240.3 mg C/g OM (1.65-fold higher than in the feedstock) and the concentrations of HA and FA were 120.7 mg C/g OM and 119.6 mg C/g OM, respectively. In FA predominated those with a molecular weight in the range of 10–30 kDa (47.2%), FA with a molecular weight >100 kDa accounted for only 14.4%. In HA, however, fraction with the highest molecular weight (>100 kDa) accounted for more than half (51.2%), while the share of HA with a molecular weight <10 kDa was only 6.8%. During composting, nitrogen loss was observed, which resulted from NH3 rather than N2O emission. In mature compost, organic nitrogen predominated (17.82 g/kg d.m.; ca. 92% of the overall nitrogen). The final concentrations of ammonia nitrogen and nitrate nitrogen were 0.23 and 1.12 g/kg d.m., respectively. The compost met the Polish requirements for the content of HMs (the HMs concentrations were as follows: Cd 1.85 mg/kg d.m., Pb 12.16 mg/kg d.m., Ni 11.05 mg/kg d.m., Cr 24.14 mg/kg d.m., Cu 104.24 mg/kg d.m., Zn 854 mg/kg d.m., Hg 0.12 g/kg d.m.). [ABSTRACT FROM AUTHOR]