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1.
Microorganisms ; 8(6)2020 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-32486515

RESUMO

In our study, we monitored the inactivation of two important viruses that are critical in animal husbandry throughout the world. To evaluate the influence of the composting process on inactivation of avian influenza virus (H9N2) in poultry manure compost (PMC) and Encephalomyocarditis virus (EMCV) in pig (swine) manure compost (SMC), the H9N2 and EMCV were injected in dialysis cassettes and buried in two different manure compost piles of poultry and pig manure, respectively. The highest temperature achieved in the PMC and SMC piles during the test period were 75 °C and 73.5 °C, respectively. At the completion of the composting for 168 h, inactivation effect appeared to be more sensitive in H9N2 than EMCV. The vitality of H9N2 decreased by 6.25±0.35 log10TCID50/mL to 0.0 log10TCID50/mL within 1 h of the composting. The vitality of EMCV decreased from 7.75±0.35 log10TCID50/mL to 1.50 log10TCID50/mL within 24 h of starting the composting process. However, the activation of EMCV was not decreased (from 7.75±0.35 to 7.50±0.71 log10TCID50/mL) in the control treatment (not inserted in composts) after 168h, while the activation of H9N2 in dialysis cassettes was significantly decreased (from 6.25±0.35 log10TCID50/mL to 2.00±0.6 log10TCID50/mL). Our study demonstrated the effectiveness of the composting treatment in inactivating the viruses studied, which was not the case with air treatment.

2.
Environ Int ; 133(Pt B): 105204, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31639602

RESUMO

Pyrolysis of swine manure (SM) was conducted as a case study to establish an environmentally sound management of livestock manure. To build a more renewable pyrolysis platform for SM, this study selected carbon dioxide (CO2) as the reaction medium. In addition, CO2 was used in pyrolysis of SM to restrict the formation of toxic compounds, such as benzene derivatives and polycyclic aromatic hydrocarbons (PAHs). A series of thermo-gravimetric analysis (TGA) tests was done to understand the thermolysis of SM in the CO2 environment. The TGA tests elucidated no occurrence of heterogeneous reactions between the SM sample and the CO2. Moreover, the TGA tests of SM suggested that SM contains more volatile matter (VM) than lignocellulosic biomass. Non-catalytic transesterification of SM lipids confirmed that the dried SM sample contained 8.85 ±â€¯0.05 wt% of lipids. This study also confirmed that the mechanistic role of CO2 was realized through the gas phase reactions between volatile pyrolysates evolved from the thermolysis of SM and CO2. In summary, CO2 donates O, enhancing the generation of CO through homogeneous reactions. In parallel, this study confirmed that CO2 suppress dehydrogenation. Therefore, the identified gas phase reactions between volatile pyrolysates and CO2 led to the compositional modifications in the condensable pyrolysates. However, such mechanistic features arising from CO2 only initiated at ≥520 °C. To expedite the reaction kinetics of the homogeneous reaction triggered by CO2, steel slag (SS) was used as a catalyst. Hence, the reaction kinetics associated with the mechanistic role of CO2 were substantially enhanced (up to 80%) when SS was used as a catalyst. Therefore, all experimental findings strongly suggest that CO2 can be utilized as a raw material in a thermo-chemical process. More importantly, all observations suggest that CO2 lopping can also be achieved in a thermo-chemical process. Lastly, this study shows that the high Cu content in SM was effectively immobilized through pyrolysis. Conclusively, this study experimentally proved that CO2 could be promising for restricting the formation of toxic pollutant in the thermo-chemical treatment in that CO2 offers an innovative and strategic means for controlling the ratio of C to H. Note that aromaticity and toxicity of chemical compounds are highly contingent on the ratio of C to H.


Assuntos
Dióxido de Carbono/química , Resíduos Industriais , Esterco , Aço , Gerenciamento de Resíduos/métodos , Animais , Biomassa , Catálise , Pirólise , Suínos
3.
Sci Total Environ ; 610-611: 992-996, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28838036

RESUMO

This report proposes a new approach to evaluate the odour nuisance of cattle manure samples from three different cattle breeds (i.e., native cattle, beef cattle, and milk cow) by means of quantification and speciation of volatile fatty acids (VFAs). To this end, non-catalytic esterification thermally induced in the presence of a porous material (silica) was undertaken, and the optimal operational parameters such as the derivatizing temperature (330°C) for the maximum yield (≥99±0.4%) of volatile fatty acid methyl esters (VFAMEs) were established. Among the VFA species in cattle manure based on quantification of VFAs, the major species were acetic, butyric and valeric acid. Considering the odour threshold of each VFA, our experimental results suggested that the major contributors to odour nuisance were C4-5 VFA species (i.e., butyric and valeric acid). Hydrothermal treatment was performed at 150°C for 0-40min to correlate the formation of VFAs with different types of cattle feed formulations. Our experimental data demonstrated that the formation of total VFAs is linearly proportional to the hydrothermal treatment duration and the total content of VFAs in native cattle, beef cattle, and milk cow manure samples reached up to ~1000, ~3200, and ~2800ppm, respectively. Thus, this study demonstrated that the degree of VFA formation is highly dependent on cattle feed formulations, which rely significantly on the protein content. Furthermore, the hydrothermal treatment provides a favourable condition for generating more VFAs. In this context, producing cattle manure into refused derived fuel (RDF) via a hydrothermal treatment is not a viable option to control odour.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Ácidos Graxos Voláteis/análise , Esterco/análise , Odorantes/análise , Animais , Bovinos , Esterificação
4.
Sci Total Environ ; 612: 103-110, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28846901

RESUMO

A novel nitrogen-doped biochar embedded with cobalt (Co-NB) was fabricated via pyrolysis of glucose pretreated with melamine (N donor) and Co(II). The Co-NB showed high catalytic capability by converting p-nitrophenol (PNP) into p-aminophenol (PAP) by NaBH4. The analyses of FE-SEM, TEM, BET, XRD, Raman, and X-ray photoelectron spectroscopy XPS of the Co-NB showed hierarchical porous structure (BET 326.5m2g-1 and pore volume: 0.2403cm3g-1) with well-dispersed Co nanoparticles (20-60nm) on the N-doped graphitic biochar surface. The Co-NB showed higher PNP reduction capability compared to the Co-biochar without N-doping, achieving 94.3% removal within 4min at 0.24gL-1 catalyst dose and initial concentration of 0.35mM PNP. Further conversion experiments under varying environmental conditions (e.g., NaBH4 concentration (7.5-30mM), biochar dosage (0.12-1.0gL-1), initial PNP concentration (0.08-0.17mM)) were conducted in batch mode. The reusability of Co-NB was validated by the repetitive conversion experiments (5cycles). The overall results demonstrated biochar potential as catalysts for environmental applications if properly designed.

5.
Bioresour Technol ; 245(Pt A): 365-371, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28898832

RESUMO

The study investigated the effect of different initial moisture (IM) content (55, 60, 65, and 70%) of composting mixtures (swine manure and sawdust) for the production of nutrient rich manure, and the recovery of ammonia through a condensation process using a vertical cylindrical in-vessel composter for 56days. The composting resulted in a significant reduction in C:N ratio and electrical conductivity (EC), with a slight increase in pH in all products. The NH3 were emitted notably, and at the same time the NO3--N concentration gradually increased with the reduction of NH4+-N in the composting mixtures. The overall results confirmed, the 65% IM showed the maximum nutritional yield, maturity and non-phytotoxic effects (Lycopersicon esculentum L.), with the results of ideal compost product in the following order of IM: 65%>60%>70%>55%. Finally, the recovered condensed ammonia contained considerable ammonium nitrogen concentrations and could be used as fertilizer.


Assuntos
Amônia , Compostagem , Esterco , Animais , Fertilizantes , Nitrogênio , Solo , Suínos
6.
Bioresour Technol ; 245(Pt A): 201-206, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28892692

RESUMO

The study investigated the effect of in-vessel composting process on Hanwoo manure in two different South Korea regions (Pyeongchang and Goechang) with sawdust using vertical cylindrical in-vessel bioreactor for 42days. The stability and quality of Hanwoo manure in both regions were improved and confirmed through the positive changes in physico-chemical and phytotoxic properties using different commercial seed crops. The pH and electrical conductivity (EC, ds/m) of composted manure in both regions were slightly increased. At the same time, carbon:nitrogen (C:N) ratio and ammonium nitrogen:nitrate nitrogen (NH4+-N:NO3--N) ratio decreased to 13.4-16.1 and 0.36-0.37, respectively. The germination index (GI, %) index was recorded in the range of 67.6-120.9%, which was greater than 50%, indicating phytotoxin-free compost. Although, composted manure values in Goechang region were better in significant parameters, overall results confirmed that the composting process could lead to complete maturation of the composted product in both regions.


Assuntos
Compostagem , Esterco , Nitrogênio , República da Coreia , Solo , Temperatura
7.
Environ Technol ; 38(9): 1191-1199, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27654710

RESUMO

The present study evaluated the phytotoxicity effect of goat manure (GM) collected from six different regions in South Korea, namely, Chupungnyeong (T1), Hoengseong (T2), Goesan (T3), Sancheong (T4), Jangsu (T5) and Namwon (T6). Phytotoxicity was assessed by means of the analysis of germination index (GI), relative seed germination (RSG), relative root elongation (RRE) and vigor index (VI) using five commercial crop varieties, namely, sesame (Sesamum indicum L.), chrysanthemum (Chrysanthemum indicum L.), carrot (Daucus carota), radish (Raphanus sativus) and cabbage (Brassica rapa). Physico-chemical parameter values were recorded at appreciable levels in all GM extracts. The effect of seedling growth was significantly different (p ≤ .05) due to the variability of nutrient content and phytotoxic effect of the extracts on the different crop seeds. Of the extracts, Goesan (T3) and Sancheong (T4) recorded the best results in the range of GI (%) (54.1-128.8) and VI (930.7-1044) and GI (%) (70.1-167.3) and VI (609.2-3034), respectively, and also showed no inhibitory effect in any of the crop seeds. Overall results also revealed that radish crops showed excellent and non-phytotoxic results in all manure extracts compared to the other crops.


Assuntos
Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Esterco/análise , Sementes/efeitos dos fármacos , Poluentes do Solo/toxicidade , Animais , Germinação/efeitos dos fármacos , Cabras , República da Coreia , Sementes/crescimento & desenvolvimento
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