Correlations between the Composition of Liquid Fraction of Full-Scale Digestates and Process Conditions

Abstract

Fast development of centralized agricultural biogas plants leads to high amounts of digestate production. The treatment and disposal of liquid fractions after on-site digestate solid–liquid separation remains problematic due to their high organic, nutrient and aromatic contents. This work aims to study the variability of the remaining compounds in the digestate liquid fractions in relation to substrate origin, process parameters and solid–liquid separation techniques. Twenty-nine digestates from full-scale codigestion biogas plants and one waste activated sludge (WAS) digestate were collected and characterized. This study highlighted the combined effect of the solid–liquid separation process and the anaerobic digestion feedstock on the characteristics of liquid fractions of digestates. Two major clusters were found: (1) liquid fractions from high efficiency separation process equipment (e.g., centrifuge and others with addition of coagulant, flocculent or polymer) and (2) liquid fractions from low efficiency separation processes (e.g., screw press, vibrating screen and rotary drum), in this latter case, the concentration of chemical oxygen demand (COD) was associated with the proportion of cow manure and energy crops at biogas plant input. Finally, SUVA254, an indicator for aromatic molecule content and the stabilization of organic matter, was associated with the hydraulic retention time (HRT).

It Works! Organic-Waste-Assisted Trichoderma spp. Solid-State Fermentation on Agricultural Digestate

“…Furthermore, the use of digestate, reducing the need for mineral fertilization, could limit nitrate pollution to water, with a significant environmental advantage if properly managed [7]. Nevertheless, several potential drawbacks in digestate management still exist, namely the transportation issue (mainly linked to ammonia emissions during storage), the different land application techniques (ammonia emissions and nitrate leaching risks) [7], the highly variable composition [8], and the presence of high metal concentrations [9]. Moreover, the inappropriate in-field application of digestate can lead to the runoff of nutrients [9] and phytotoxic responses [10].…”

Diversifying the products from the organic fraction of municipal solid waste (OFMSW) by producing polyhydroxyalkanoates from the liquid fraction and biomethane from the residual solid fraction

“…Then, the slurry was filtered through 100 μm nylon mesh to separate solid and liquid fractions. The separation efficiency was calculated as previously reported (Akhiar et al, 2021), and was of 98.6±0.1%. Both the recovered solid biomass and liquid fractions were stored at -20°C for later use.…”

Pengaruh Literasi Keuangan, Inklusi Keuangan dan Akses Permodalan Terhadap Keberlanjutan UMKM Pada Bidang Fashion Di Kota Denpasar

“…Literasi keuangan sangat penting bagi pengusaha UMKM, karena literasi keuangan dapat memberdayakan UMKM tentang sumber-sumber pendanaan dari keterampilan yang akan membekali UMKM untuk menimbang pilihan mereka dalam mencari pembiayaan untuk mengoptimalkan struktur keuangannya. Untuk mewujudkan peningkatan jumlah UMKM maka perlu pembinaan dalam menunjang keberlanjutan UMKM dengan cara memberikan pemahaman terhadap literasi keuangan (Akhiar et al, 2021). Sejumlah penelitian menemukan bahwa literasi keuangan mampu meningkatkan keberlanjuta UMKM secara positif (Dermawan, 2019), (Ye & Kulathunga, 2019).…”

“…Wulandari et al, 2020). Sejumlah penelitian menemukan bahwa inklusi keuangan mampu meningkatkan keberlanjuta UMKM secara positif (Akhiar et al, 2021), (Dermawan, 2019).…”