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volatilefattyacids, etc ; dairy science; histamine; livestock; metabolism; pH; temperature; Show all 7 Subjects
Abstract:
... Quantifying digestive and fermentative processes within the rumen environment has been the subject of decades of research; however, our existing research methodologies preclude time-sensitive and spatially explicit investigation of this system. To better understand the temporal and spatial dynamics of the rumen environment, real-time and in situ monitoring of various chemical and physical paramete ...
volatilefattyacids, etc ; ammonia; anaerobic digestion; biogas; methane; nitrogen; pH; solubilization; Show all 8 Subjects
Abstract:
... Ammonia recovery from anaerobic digesters via side-stream stripping is a technique to recover nitrogen from manure wastes. This study demonstrated a novel approach to determining ammonia recovery to maintain total ammonia concentrations in the digester in the range of 1.7–2.1 gN/L. Increasing the pH during stripping from 8, 8.5 to 9.5 did not affect the stability of the digester. Methane yields of ...
volatilefattyacids, etc ; Archaea; anaerobic digestion; biogas; graphene oxide; municipal solid waste; Show all 6 Subjects
Abstract:
... The present research investigated the impact of reduced graphene oxide (rGO) addition on the semi-continuous anaerobic digestion of the organic fraction of municipal solid waste (OFMSW) in the range of 0.5–10 gVolatileSolid(VS)/Lᵣₑₐcₜₒᵣday organic loading rates (OLR). Adding rGO enhanced the rate and yield of biomethane production, and the maximum biomethane increment rate was obtained as 110% at ...
volatilefattyacids, etc ; acetates; ammonium nitrogen; automation; cottonseed; cottonseed meal; energy; fermentation; gossypol; Show all 9 Subjects
Abstract:
... To explore whether or not the gossypol varied in cottonseed by-products affect rumen degradability and fermentation efficiency, an in vitro cumulative gas production experiment was applied with mixed rumen microorganism to compare rumen fermentation characteristics of whole cottonseed (WCS, n = 3 samples), cottonseed meal (CSM, n = 3 samples), and cottonseed hull (CSH, n = 2 samples). The five-rep ...
volatilefattyacids, etc ; biochar; calcium hydroxide; environmental management; methane production; sodium hydroxide; wastes; Show all 7 Subjects
Abstract:
... Commercial digesters handling complex waste and organic overloading often encounter unbalanced conditions or failures. With limited studies on the digester recovery from an industry-based waste stream, a complex and high-strength digestate containing up to 79 g COD l⁻¹ from acidified commercial digester was investigated for biochar and alkaline treatments. The addition of biochar and calcium hydro ...
volatilefattyacids, etc ; atmospheric pressure; carbon dioxide; fermentation; headspace analysis; inorganic carbon; pH; Show all 7 Subjects
Abstract:
... Addressing the carbon emissions through microbial mediated fermentation is an emerging interest. Custom designed and fabricated gas fermentation (GF) systems were evaluated to optimize the headspace pressure, pH (6.5, 7.5, and 8.5), fermentation time, and substrate concentration by employing enriched homoacetogenic chemolithoautotrophs in non-genetic approach. Headspace pressure showed marked infl ...
volatilefattyacids, etc ; Holstein; Prevotella; fermentation; propionic acid; selenium; sodium selenite; species richness; Show all 8 Subjects
Abstract:
... AIMS: This study aims to investigate the effect of hydroxy‐selenomethionine supplementation on the in vitro rumen fermentation characteristics and microorganisms of Holstein cows. METHODS AND RESULTS: Five fermentation substrates, including control (without selenium supplementation, CON), sodium selenite supplementation (0.3 mg kg⁻¹ DM, SS03), and hydroxy‐selenomethionine supplementation (0.3, 0.6 ...
volatilefattyacids, etc ; acetic acid; chickens; crop production; genes; nitrogen; phosphorus; poultry manure; waste management; Show all 9 Subjects
Abstract:
... Bioponics has the potential to recover nutrients from organic waste streams, such as chicken manure and digestate with high volatile fatty acid (VFA) contents through crop production. Acetic acid, a dominant VFA, was supplemented weekly (0, 500, 1000, and 1500 mg/L) in a chicken manure-based bioponic system, and its effect on the performance of bioponics (e.g., plant yield and nitrogen and phospho ...
volatilefattyacids, etc ; Bacillaceae; acetic acid; fermentation; microbial communities; organic wastes; pH; propionic acid; sludge; Show all 9 Subjects
Abstract:
... Alkaline co-fermentation of primary sludge and external organic waste (OW) was studied to elucidate the influence of substrate ratios and long-term system robustness and microbial community dynamics using batch and semi-continuous reactors. Volatile fatty acid (VFA) production increased with increasing OW fraction in the substrate due to synergistic effects of co-degradation. VFA production at pH ...
volatilefattyacids, etc ; activated carbon; anaerobic digestion; inoculum; methane production; methanogens; pyrolysis; vinegars; waste management; Show all 9 Subjects
Abstract:
... Random disposal of waste tires and vinegar residues is deleterious to the environment; these materials can be sufficiently treated using pyrolysis and anaerobic digestion, respectively. In this study, pyrolytic carbon was used to enhance the performance of the anaerobic digestion of vinegar residues, which is a much more economic method comparing with dosing commercial-level carbon based materials ...
volatilefattyacids, etc ; Methanobacterium; Syntrophobacter; ammonia; ammonium nitrogen; anaerobic digestion; bioaugmentation; methane production; methanogens; poultry manure; Show all 10 Subjects
Abstract:
... Volatile fatty acid (VFA) accumulation caused by high ammonia concentrations is often encountered during the anaerobic digestion (AD) of ammonia-rich substrates. In this study, propionate-degrading methanogenic cultures were introduced to augment the semi-continuous AD of chicken manure under high ammonia levels. Introduction of a methanogenic culture enhanced the methane yield in the bioaugmented ...
volatilefattyacids, etc ; alkanes; carbon dioxide; chemistry; commercialization; coproducts; fuel production; hexanoic acid; process design; streams; Show all 10 Subjects
Abstract:
... Ketonization of wet waste-derived carboxylic acids (volatile fatty acids, VFAs) constitutes the first step of a process to catalytically upgrade VFAs to an alkane sustainable aviation fuel blendstock. VFA ketonization has been demonstrated at near-theoretical yields at the lab scale, and robust operation of industrial-scale ketonization reactors is essential for the commercialization of VFA upgrad ...
... Semi-continuous experiments were carried out in lab-scale continuous stirred tank reactors to evaluate the effects of fermentation temperature (37 ± 1 °C and 55 ± 1 °C) and total solids (TS) contents (3 %, 6 %, and 12 %) on biohydrogen production from the dark fermentations (DF) of rice straw (RS) and the total operation duration was 105 days. The experimental results show that biohydrogen product ...
volatilefattyacids, etc ; Clostridium; amino acids; bioreactors; biotransformation; chemotaxis; fermentation; kitchen waste; metagenomics; oxidoreductases; protein synthesis; transportation; Show all 12 Subjects
Abstract:
... During proteinaceous waste valorization to produce volatile fatty acids (VFAs), protein needs to be hydrolyzed to amino acids (AAs), but the effects of the configuration of AAs on their biotransformation and VFA production have not been investigated. In this study, more residual d-AAs than their corresponding l-AAs were observed after VFAs were produced from kitchen waste in a pilot-scale bioreact ...
... This study evaluated the effectiveness of shrimp shell biochar (SBC) and nickel (Ni) loaded SBC in increasing methane yield during anaerobic digestion of food waste. The results indicated that the methane yields of control (without SBC), SBC, SBC loaded with the low concentration of Ni, and SBC loaded with the high concentration of Ni were 81.8, 116.1, 134.7, and 99.2 mL/(g·VS), respectively. SBC ...
... The current study aimed to determine the effects of NH₄⁺ on anaerobic digestion (AD) metabolism and the feasibility of using NH₄HCO₃ to improve methane production in an AD system when treating a low-C/N-ratio food waste (FW). Increasing the ammonium concentration (500–1000 mg NH₄Cl-N/L) added into the AD system did not limit the methane production but caused the volatile fatty acid (VFA) accumulat ...
... Kitchen wastes (KW) dramatically increasing with population and economy enhancing, and dry anaerobic fermentation was used to treat it. However, the large amount of biogas residue severely restricted the application of dry anaerobic fermentation, because the high total solid might lead to the system failure. Therefore, it is urgent to find appropriate way to improve the efficiency of dry anaerobic ...
volatilefattyacids, etc ; Clostridia; Methanosaeta; chemical oxygen demand; fatty acid composition; membrane bioreactors; methanogens; polyvinyl alcohol; ultrafiltration; wastewater; Show all 10 Subjects
Abstract:
... This study investigated the effects of adding polyvinyl alcohol (PVA) beads on the performance of methanogenic reactors and the fouling behavior of a two-stage thermophilic anaerobic membrane bioreactor (ThAnMBR) for treating wastewater at a feed chemical oxygen demand (COD) of 10 g/L. The PVA-added methanogenic reactor exhibited stable operation performance and offered a relatively low volatile f ...
Newton A. Ihoeghian; Andrew N. Amenaghawon; Mike U. Ajieh; Cyprian E. Oshoma; Abraham Ogofure; Nosakhare O. Erhunmwunse; Valerie I.O. Edosa; Isioma Tongo; Ifeyinwa S. Obuekwe; Ebuwa S. Isagba; Christopher Emokaro; Lawrence I.N. Ezemonye; Alfonso J. Lag-Brotons; Kirk T. Semple; Alastair D. Martin
volatilefattyacids, etc ; ammonium nitrogen; anaerobic digestion; biogas; carbon nitrogen ratio; cattle; food waste; gas production (biological); models; pH; Show all 10 Subjects
Abstract:
... This study investigated the batch co-digestion of cattle rumen content (CRC) and food waste (FW) for biogas production in different ratios (CRC:FW) to assess biogas production and process stability. The results showed that CRC and FW possess characteristics that are desirable for biogas production as seen in their respective total solids (10.85 and 26.53%), volatile solids (89 and 86.83%) and carb ...
volatilefattyacids, etc ; ammonia; ammonium nitrogen; anaerobic digestion; carbon; feedstocks; gas production (biological); lignocellulose; liver; methanogens; pork; slaughterhouse wastes; Show all 12 Subjects
Abstract:
... The study explored slaughterhouse waste (SHW) as prime feedstock associated with and without supplement of an external slowly degradable lignocellulosic carbon source to overcome the synergistic co-inhibitions of ammonia and fatty acids. Long-term solid-state digestion (SSD) and liquid-state digestion (LSD) were investigated using a mixture of pork liver and fat. At 2.0 g volatile solids (VS) L⁻¹ ...