scholarly journals Dark Fermentation of Sweet Sorghum Stalks, Cheese Whey and Cow Manure Mixture: Effect of pH, Pretreatment and Organic Load

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 1017
Author(s):  
Margarita Andreas Dareioti ◽  
Aikaterini Ioannis Vavouraki ◽  
Konstantina Tsigkou ◽  
Constantina Zafiri ◽  
Michael Kornaros
Keyword(s):  
Fatty Acids ◽  
Hydrogen Production ◽  
Sweet Sorghum ◽  
Volatile Fatty Acids ◽  
Cheese Whey ◽  
Dark Fermentation ◽  
Organic Load ◽  
Anaerobic Sludge ◽  
Hydrogen Yield ◽  
Cow Manure

The aim of this study was to determine the optimal conditions for dark fermentation using agro-industrial liquid wastewaters mixed with sweet sorghum stalks (i.e., 55% sorghum, 40% cheese whey, and 5% liquid cow manure). Batch experiments were performed to investigate the effect of controlled pH (5.0, 5.5, 6.0, 6.5) on the production of bio-hydrogen and volatile fatty acids. According to the obtained results, the maximum hydrogen yield of 0.52 mol H2/mol eq. glucose was measured at pH 5.5 accompanied by the highest volatile fatty acids production, whereas similar hydrogen productivity was also observed at pH 6.0 and 6.5. The use of heat-treated anaerobic sludge as inoculum had a positive impact on bio-hydrogen production, exhibiting an increased yield of 1.09 mol H2/mol eq. glucose. On the other hand, the pretreated (ensiled) sorghum, instead of a fresh one, led to a lower hydrogen production, while the organic load decrease did not affect the process performance. In all experiments, the main fermentation end-products were volatile fatty acids (i.e., acetic, propionic, butyric), ethanol and lactic acid.

scholarly journals Anaerobic treatment of high-sulfate wastes

1986 ◽  
Vol 13 (4) ◽  
pp. 423-428 ◽  
Author(s):  
Jan A. Oleszkiewicz ◽  
Barry L. Hilton
Keyword(s):  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Cheese Whey ◽  
Oxygen Demand ◽  
Anaerobic Treatment ◽  
Pulp And Paper ◽  
Anaerobic Sludge ◽  
Dairy Wastes ◽  
High Sulfate ◽  
Cooking Liquor

Six parallel upflow anaerobic sludge bed reactors were operated at chemical oxygen demand (COD) loads from 3 to 10 kg COD/(m3∙d). Four reactors (R1–R4) were fed sodium sulfate at loads of 1–3 kg S-SO4/(m3∙d). Reactors R1 and R2 were fed spent cheese whey with R1 being operated in an unstripped and R2 in a stripped mode. At COD loads below 5 kg/(m3∙d), the removal in R1 was 60–80% COD and generally trailed R2 by a margin of 0–15%. At higher COD loads and at higher SO4/COD ratios, the performance of R1 deteriorated significantly. A similar situation was found in the pair R3 (unstripped) and R4 (stripped), which was fed a mixture of spent whey and sulfite cooking liquor. Reactors R5 and R6 were subjected to the same feed as R3 and R4, but no sulfate was added. A comparison of R4 with R6 indicated slightly lower COD removal in R4 with similar amounts of volatile fatty acids accumulating in both reactors in cases of overloading. Key words: anaerobic treatment, sulfides, methanogenesis, inhibition, sludge bed reactor, dairy wastes, pulp and paper wastes, sulfate reduction.

scholarly journals Effect of pH on the Economic Potential of Dark Fermentation Products from Used Disposable Nappies and Expired Food Products

2021 ◽  
Vol 11 (9) ◽  
pp. 4099
Author(s):  
Dimitris Zagklis ◽  
Marina Papadionysiou ◽  
Konstantina Tsigkou ◽  
Panagiota Tsafrakidou ◽  
Constantina Zafiri ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Hydrogen Production ◽  
Volatile Fatty Acids ◽  
Food Products ◽  
Treatment Method ◽  
Dark Fermentation ◽  
Biodiesel Production ◽  
Economic Potential ◽  
Fermentation Products ◽  
Ph Values

Used disposable nappies constitute a waste stream that has no established treatment method. The purpose of this study was the assessment of the dark fermentation of used disposable nappies and expired food products under different pH values. The biodegradable part of the used disposable nappies was recovered and co-fermented with expired food products originating from supermarkets. The recoverable economic potential of the process was examined for different volatile fatty acids exploitation schemes and process pH values. The process pH strongly affected the products, with optimum hydrogen production at pH 6 (4.05 NLH2/Lreactor), while the amount of produced volatile fatty acids was maximized at pH 7 (13.44 g/L). Hydrogen production was observed at pH as low as pH 4.5 (2.66 NLH2/Lreactor). The recoverable economic potential was maximized at two different pH values, with the first being pH 4.5 with minimum NaOH addition requirements (181, 138, and 296 EUR/ton VS of substrate for valorization of volatile fatty acids through microbial fuel cell, biodiesel production, and anaerobic digestion, respectively) and the second being pH 6, where the hydrogen production was maximized with the simultaneous production of high amounts of volatile fatty acids (191, 142, and 339 EUR/ton VS of substrate respectively).

Sequential generation of hydrogen and lipids from starch by combination of dark fermentation and microalgal cultivation

RSC Advances ◽  
2015 ◽  
Vol 5 (94) ◽  
pp. 76779-76782 ◽  
Author(s):  
Hong-Yu Ren ◽  
Bing-Feng Liu ◽  
Fanying Kong ◽  
Lei Zhao ◽  
Nan-Qi Ren
Keyword(s):  
Fatty Acids ◽  
Hydrogen Production ◽  
Volatile Fatty Acids ◽  
Lipid Production ◽  
Dark Fermentation ◽  
Simultaneous Treatment ◽  
Microalgal Cultivation ◽  
Fermentative Hydrogen Production ◽  
Fermentative Hydrogen ◽  
Sequential Generation

Dark fermentative hydrogen production and microalgal lipid production was successfully combined to enhance the energy conversion from starch with simultaneous treatment of volatile fatty acids in the effluent.

scholarly journals Biological hydrogen production from synthetic wastewater by an anaerobic migrating blanket reactor: Artificial neural network (ANN) modeling

2019 ◽  
Vol 6 (4) ◽  
pp. 269-276
Author(s):  
Mohammad Ghasemian ◽  
Ensiyeh Taheri ◽  
Ali Fatehizadeh ◽  
Mohammad Mehdi Amin
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Hydrogen Production ◽  
Volatile Fatty Acids ◽  
Synthetic Wastewater ◽  
Anaerobic Sludge ◽  
Hydrogen Yield ◽  
Biological Hydrogen Production ◽  
Artificial Neural ◽  
Artificial Neural Network Ann

Background: This study aimed to evaluate an anaerobic migrating blanket reactor (AMBR) for biological hydrogen production, and also to investigate its capability to treat synthetic wastewater. Methods: A five-compartment AMBR (9 L effective volume) was made by Plexiglas and seeded with thermal pretreated anaerobic sludge at 100°C for 30 minutes. The AMBR was operated at mesophilic temperature (37 ± 1°C) with continuous fed of synthetic wastewater at five organic loading rates (OLRs) of 0.5 to 8 g COD/L.d. Results: It was revealed that as the OLR increased from 0.5 to 8 g COD/L.d, the hydrogen production and also volumetric hydrogen production rate (VHPR) improved. Increasing the OLR over this range, led to a decrease in the average hydrogen yield from 1.58 ± 0.34 to 0.97 ± 0.45 mol H2 /mol glucose. The concentration of both volatile fatty acids (VFAs) and solvents kept increasing with OLR. During the AMBR operation, the dominant soluble end products (SEPs) were acetic and butyric acids in all of the OLRs studied. Conclusion: Based on the results, the hydrogen yield was related to the acetate/butyrate fermentation. The artificial neural network (ANN) model was well-fitted to the experimental obtained data from the AMBR, and was able to simulate the chemical oxygen demand (COD) removal and hydrogen production

scholarly journals The Start-Up of Continuous Biohydrogen Production from Cheese Whey: Comparison of Inoculum Pretreatment Methods and Reactors with Moving and Fixed Polyurethane Carriers

2021 ◽  
Vol 11 (2) ◽  
pp. 510
Author(s):  
Elza R. Mikheeva ◽  
Inna V. Katraeva ◽  
Andrey A. Kovalev ◽  
Dmitriy A. Kovalev ◽  
Alla N. Nozhevnikova ◽  
...  
Keyword(s):  
Cheese Whey ◽  
Hydraulic Retention Time ◽  
Continuous Production ◽  
Oxygen Demand ◽  
Organic Load ◽  
Anaerobic Sludge ◽  
Acid Pretreatment ◽  
Methanogenic Activity ◽  
Start Up ◽  
Load Rate

This article presents the results of the start-up of continuous production of biohydrogen from cheese whey (CW) in an anaerobic filter (AF) and anaerobic fluidized bed (AFB) with a polyurethane carrier. Heat and acid pretreatments were used for the inactivation of hydrogen-scavengers in the inoculum (mesophilic and thermophilic anaerobic sludge). Acid pretreatment was effective for thermophilic anaerobic sludge to suppress methanogenic activity, and heat treatment was effective for mesophilic anaerobic sludge. Maximum specific yields of hydrogen, namely 178 mL/g chemical oxygen demand (COD) and 149 mL/g COD for AFB and AF, respectively, were obtained at the hydraulic retention time (HRT) of 4.5 days and organic load rate (OLR) of 6.61 kg COD/(m3 day). At the same time, the maximum hydrogen production rates of 1.28 and 1.9 NL/(L day) for AF and AFB, respectively, were obtained at the HRT of 2.02 days and OLR of 14.88 kg COD/(m3 day). At the phylum level, the dominant taxa were Firmicutes (65% in AF and 60% in AFB), and at the genus level, Lactobacillus (40% in AF and 43% in AFB) and Bifidobacterium (24% in AF and 30% in AFB).

Coproduction of hydrogen and volatile fatty acids via integrated two-step fermentation of sweet sorghum stalks by alkaline and enzymatic treatment

2021 ◽  
Vol 145 ◽  
pp. 105923
Author(s):  
Md Saiful Islam ◽  
Zeju Zhang ◽  
Song-Ben Qu ◽  
Chun-Lei Liu ◽  
Chen Guo ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Sweet Sorghum ◽  
Volatile Fatty Acids ◽  
Enzymatic Treatment

Use of organic waste for biohydrogen production and volatile fatty acids via dark fermentation and further processing to methane

2019 ◽  
Vol 44 (44) ◽  
pp. 24110-24125 ◽  
Author(s):  
Tobias Weide ◽  
Elmar Brügging ◽  
Christof Wetter ◽  
Antonio Ierardi ◽  
Marc Wichern
Keyword(s):  
Fatty Acids ◽  
Organic Waste ◽  
Volatile Fatty Acids ◽  
Dark Fermentation ◽  
Biohydrogen Production

scholarly journals Diagnosis and Monitoring of Volatile Fatty Acids Production from Raw Cheese Whey by Multiscale Time-Series Analysis

2021 ◽  
Vol 11 (13) ◽  
pp. 5803
Author(s):  
Antonio Lara-Musule ◽  
Ervin Alvarez-Sanchez ◽  
Gloria Trejo-Aguilar ◽  
Laura Acosta-Dominguez ◽  
Hector Puebla ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Time Series ◽  
Time Series Analysis ◽  
Multiscale Analysis ◽  
Volatile Fatty Acids ◽  
Cheese Whey ◽  
Anaerobic Treatment ◽  
Operating Conditions ◽  
Series Analysis ◽  
Key Variables

Anaerobic treatment is a viable alternative for the treatment of agro-industrial waste. Anaerobic digestion reduces organic load and produces volatile fatty acids (VFA), which are precursors of value-added products such as methane-rich biogas, biohydrogen, and biopolymers. Nowadays, there are no low-cost diagnosis and monitoring systems that analyze the dynamic behavior of key variables in real time, representing a significant limitation for its practical implementation. In this work, the feasibility of using the multiscale analysis to diagnose and monitor the key variables in VFA production by anaerobic treatment of raw cheese whey is presented. First, experiments were carried out to evaluate the performance of the proposed methodology under different operating conditions. Then, experimental pH time series were analyzed using rescaled range (R/S) techniques. Time-series analysis shows that the anaerobic VFA production exhibits a multiscale behavior, identifying three characteristic regions (i.e., three values of Hurst exponent). In addition, the dynamic Hurst exponents show satisfactory correlations with the chemical oxygen demand (COD) consumption and VFA production. The multiscale analysis of pH time series is easy to implement and inexpensive. Hence, it could be used as a diagnosis and indirect monitoring system of key variables in the anaerobic treatment of raw cheese whey.

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