Predicting anaerobic biogasification potential of ingestates and digestates of a full-scale biogas plant using chemical and biological parameters

The aim of this work was to develop simple and fast tests to predict anaerobic biogasification potential (ABP) of ingestates and digestates from a biogas plant. Forty-six samples of both ingestates and digestates were collected within an eight-month observation period and were analyzed in terms of biological and chemical parameters, namely, ABP test, oxygen demand in a 20-h respirometric test (OD20), total solids (TS), volatile solids (VS), total organic carbon (TOC), total Kjeldahl nitrogen (TKN), ammonia, cell solubles (CS), acid detergent fibers (ADF), lignin (ADL), cellulose, and hemicellulose. Considering both quantitative (VS and TOC) and qualitative aspects (OD20 and CS) of organic matter (OM), four models (linear regressions; 0.80 < R2 < 0.913; 16% < standard errors < 23%) were proposed to predict ABP. The models were chosen according to the needed accuracy of the evaluation in terms of time schedule and the availability of the required laboratory analyses

The anaerobic digestion process capability to produce biostimulant : the case study of the dissolved organic matter (DOM) vs. auxin-like property

Biostimulants improve plant growth by stimulating nutrient uptake and efficiency, improving tolerance to abiotic stress and raising crop quality. Biostimulants are currently only recognised in five categories. However, the recent interest in this sector has led to the identification of some new ones. The aim of this work was to study the auxin-like activity of digestate dissolved organic matter (DOM) obtained from full scale anaerobic digester plants. All DOMs had biostimulant capacity comparable with humic acid and amino acids. The auxin-like activities depended mainly on the hydrophobic DOM fractions for the presence of auxin-active and other auxin-like molecules. Significant correlations were found for the auxin-effect in relation to auxin-active molecules and fatty acids responsible for most of the auxin-like effects (67% of the total importance in giving auxin-like activity) while a minor or null contribution was attributable to the carboxylic acids and aminoacid categories. Therefore, the anaerobic digestion process seems to be a useful biotechnology to produce biostimulants. Basing on these first results, the expanding anaerobic digestion sector could become important for the production of new biostimulant classes to meet the agricultural sector's new requirements and saving on raw materials

Evaluation of hormone-like activity of the dissolved organic matter fraction (DOM) of compost and digestate

Biomasses are usually applied to soil for their agronomic properties (fertilization and amendment properties). Biomass can also have bio-stimulating effects on plants because of the presence of hormones and hormone-like molecules. Although compost has been the subject for studies of this aspect, no data have yet been reported on the extraction of this kind of molecule from digestate biomass. The aim of this work is to study the auxin- and gibberellin-like activity of pig slurry digestate in comparison with those of pruning and garden wastes compost's dissolved organic fraction (DOM). DOM (i.e., fraction. <. 0.45. \u3bcm) is the most reactive among the organic matter fractions readily available to microbial and plant metabolism. No gibberellin-like activities were found for either compost or digestate, whereas digestate showed auxin-like properties which were found to be located in its neutral hydrophobic (NHo) DOM fractions. Hormone activity was due principally to the presence of auxin coming from the anaerobic digestion of aromatic amino acids

Substituting energy crops with organic fraction of municipal solid waste for biogas production at farm level: A full-scale plant study

The aim of this study was to evaluate the possibilities of replacing the energetic crop (EC) in the feed-in mixture (ingestate) with the organic fraction of municipal solid waste (OFMSW), in an anaerobic full-scale plant comprising four continuous stirred tank reactors (CSTRs) along with post-digester. A full-scale plant performing anaerobic digestion (AD) was monitored for 8 months, and during this period, 55 samples of both ingestates and digestates from the digesters (hydraulic retention time, HRT, of 40 d) and post-digester (HRT of 10 d) were collected before and after OFMSW introduction and analyzed for both biological and chemical parameters. The result obtained showed that substitution of EC (Mix A) with OFMSW (Mix B) did not lead to substantial modification of the feed-in mixture and AD process. Mixtures A and B gave similar specific biogas (i.e., 585 \ub1 198 m3 Mg TS-1 and 567 \ub1 162 m3 Mg TS-1 for Mix A and B, respectively), showing high process performances, i.e., 95% of the total anaerobic biogas producible was produced during the AD processes (HRT of 50 d). The digestates produced showed similar characteristics and can be potentially used in agriculture. The OFMSW offers new opportunities for farmers to produce renewable energy, by lowering the cost of the biomass and producing a useful fertilizer/amendment product

Evoluci&#243;n de la materia org&#225;nica en una instalaci&#243;n de compostaje de lodos de depuradora urbanos

Sewage sludge valorization is currently performed mainly through biological processes (anaerobic digestion and composting). Even thought the composting process is well known from the point of view of its operation and process parameters, the evolution of organic matter along the process has been less studied. In this sense, this article uses two novel analytical techniques to follow the evolution of the organic matter during the composting of sewage sludge in an industrial facility. The applied techniques are dynamic respi-rometry and pyrolysis GC/MS

Opening bio-based markets via standards, labelling and procurement : Validated biogasification test

Public summaryWork package 6Managed end-of-life optionsDeliverable N° 6.8:<br/

Opening bio-based markets via standards,labelling and procurement : Validation of lab and mesocosm tests against field experiments

Work package 5. In situ biodegradation Deliverable N° 5.6: Validation of lab and mesocosm tests against field experiment

Opening bio-based markets via standards,labelling and procurement : Marine degradation test lab assessment: Marine degradation test of bio-based materials at laboratory and mesocosm scale assessed

Public summaryWork package 5In situ biodegradationDeliverable N° 5.