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Liquids obtained by fractional condensation of pyrolysis vapors from two types of lignocellulosic biomass, namely Jerusalem artichoke stalk (high cellulose and ash contents) and white birch bark (high lignin and extractive contents), were compared. Using two condensers connected in series, a dark oily fraction rich in phenolic compounds and sugar derivatives was obtained at 90 °C (respectively, 14% of total polyphenols and 11% of total carbohydrates for the oily fraction from the agricultural stalk) followed by aqueous fraction at 0 °C. Stalk yielded a homogeneous oily fraction whereas the bark oily liquid was heterogeneous, due possibly to lignin pyrolysis products. Both yielded clear orange aqueous fractions having a chemical composition close to wood vinegar, > 60% water, and high concentrations of acetic acid, with also a significant content of polyphenols, around 5%. This study showed that fractional condensation could be a vital tool in pyrolysis-based biorefinery producing an oily (application as an energy source or as a chemical feedstock) and an aqueous fraction (applications as biocide or biostimulation in agriculture) by pyrolysis of vastly different lignocellulosic biomasses.

ABSTRACTRecycled manure solids (RMS) produced in dairy farms from fresh manure need to be sanitized before using them as bedding material. However, the impact on air quality of composting RMS remains unknown. Four RMS composting methods were tested during a 10-day aging of piles in experimental chambers: static windrow (SW), turned windrow (TW), SW following drum composting for 24 h (DC24) or SW following drum composting for 72 h (DC72). Air samples were collected using a SASS®3100 Dry Air Sampler on days 0 (pilling of the RMS), 5, and 10. Bacteria (16S rRNA genes), Penicillium/Aspergillus, A fumigatus, and 11 human pathogenic bacteria (e.g. Klebsiella pneumonia) were quantified by qPCR while endotoxins and dust particles were, respectively, measured by LAL assays and with a DustTrakTMDRX Aerosol Monitor. On day 0, RMS produced by SW and TW yielded the lowest concentrations of airborne bacteria, while DC24 resulted in the lowest levels of Penicillium/Aspergillusand dust particles. SW method led on day 5 to the lowest concentration of bacteria and Penicillium/Aspergillus, and DC24 and DC72 to the lowest concentration of airborne dust. On day 10, SW and TW piles were associated with the lowest levels of Penicillium/Aspergillusand dust particles. A significant difference was observed between concentration of airborne bacteria, Penicillium/Aspergillusand endotoxins before and during the turnover of TW piles. None of the studied human pathogens was detected in the air samples. Results of the present study suggest that SW and TW are the most promising methods for the production of composted RMS with respect to microbial air quality. However, the experimental chambers do not accurately represent commercial dairy barns and further research on these composting methods is necessary. Finally, the study highlights that bedding material and its management may be determinant factors for air quality in dairy barns.Implications: The research evaluated the impact on microbial air quality of composting recycled manure solids (RMS) produced from fresh cow manure. RMS need to be composted or sanitized before using them as bedding material for animals. The impact on animal health of RMS still needs to be confirmed, while the effect on air quality and the health of dairy farmers is unknown. In the present study, microbial air quality associated with four RMS composting methods was investigated. Data revealed that two methods resulted in lower aerosolization of dust particles, endotoxins, molds, and bacteria.

In the present study, physical, chemical, morphological, crystallographic analysis of the non-treated and treated (100°C during 30min) sugarcane bagasse fibers were examined. Sugarcane bagasse fibers pre-treatment effect on the Portland cement hydration was monitored by inhibition tests and differential scanning calorimetry in the first 24h. Furthermore, 28 days age physical-mechanical properties of cement composite materials with sugarcane bagasse fibers were also evaluated. Inhibition index of treated sugarcane bagasse fibers was 5.9%, while for the non-treated sugarcane bagasse fibers it was 67.3%. Cement composites containing treated sugarcane bagasse fibers showed lower physical properties (water absorption and thickness swelling) than the cement composites reinforced with non-treated sugarcane bagasse fibers (p<0.05). Likewise, mechanical properties under flexure (modulus of rupture, MOR, and modulus of elasticity, MOE) of cement composites with treated sugarcane bagasse fibers showed higher values than the cement composites with non-treated sugarcane bagasse fibers (p<0.05), thus proving the pre-treatment efficiency on sugarcane bagasse fibers for cement composites.

Antibiotics are used to fight bacterial infections. However, a selective pressure gave rise to bacteria resistant to antibiotics. This leaves scientists worried about the danger to human and animal health. Some strategies can be borrowed to reduce the use of antibiotics in chicken farms. Much research has been carried out to look for natural agents with similar beneficial effects of growth promoters. The aim of these alternatives is to maintain a low mortality rate, a good level of animal yield while preserving environment and consumer health. Among these, the most popular are probiotics, prebiotics, enzymes, organic acids, immunostimulants, bacteriocins, bacteriophages, phytogenic feed additives, phytoncides, nanoparticles and essential oils.