A method for simultaneous bioflocculation and pretreatment of algal biomass targeting improved methane production

Novel two fold approach comprising short duration fungal crude enzyme pretreatment of algal biomass followed by codigestion with cattle dung resulting in enhanced methane yield is disclosed.

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Improved methane yield from wastewater grown algal biomass

Water Science & Technology ◽

10.2166/wst.2018.029 ◽

2018 ◽

Vol 78 (1) ◽

pp. 81-91 ◽

Cited By ~ 1

Author(s):

Mohit Thawani ◽

Nidhi Hans ◽

Saurabh Samuchiwal ◽

Sanjeev Kumar Prajapati

Keyword(s):

Methane Production ◽

Algal Biomass ◽

Room Temperature ◽

Oxygen Demand ◽

Microscopic Analysis ◽

Growth Period ◽

Methane Yield ◽

Dissolved Phosphorus ◽

Soluble Chemical Oxygen Demand ◽

Fluorescence Microscopic Analysis

Abstract Methane production from the algal biomass cultivated in a laboratory scale continuous photobioreactor (PBR) using sewage was evaluated in the present work. During the preliminary experiments, algal biomass reached up to 1.69 ± 0.35 g L–1 in 12 days' growth period. Besides, 65 to 100% removal in concentrations of total dissolved phosphorus (TDP), nitrate nitrogen (NO3–N), total ammoniacal nitrogen (TAN) and soluble chemical oxygen demand (sCOD) was also recorded. The sCOD removal in the reactor was 100%, whereas removal of TDP, NO3–N and TAN were up to 75, 40 and 92%, respectively. Upon anaerobic digestion, the fresh algal biomass showed methane yield of 180 mL g–1 VSfed. Further, algal biomass was stored under natural conditions in open containers (aerobic conditions) in darkness at room temperature (27–30 °C) for 72 h. Interestingly, >48% COD solubilization from algal biomass was observed during storage. Pretreatment through natural storage was further confirmed with qualitative observations including scanning electron and fluorescence microscopic analysis. Moreover, higher methane yield (284.38 mL g–1 VSfed) was observed from the samples stored for 60 h. Thus, natural storage for a designated period may be recommended as a prerequisite stage in the process of methane production from wastewater-grown algal biomass.

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Enhancing methane production from the invasive macroalga Rugulopteryx okamurae through anaerobic co-digestion with olive mill solid waste: process performance and kinetic analysis

Journal of Applied Phycology ◽

10.1007/s10811-021-02548-3 ◽

2021 ◽

Author(s):

D. de la Lama-Calvente ◽

M. J. Fernández-Rodríguez ◽

J. Llanos ◽

J. M. Mancilla-Leytón ◽

R. Borja

Keyword(s):

Anaerobic Digestion ◽

Solid Waste ◽

Methane Production ◽

Methane Yield ◽

Specific Rate ◽

Order Kinetic ◽

Two Phase ◽

First Order ◽

Olive Mill Solid Waste ◽

Olive Mill

AbstractThe biomass valorisation of the invasive brown alga Rugulopteryx okamurae (Dictyotales, Phaeophyceae) is key to curbing the expansion of this invasive macroalga which is generating tonnes of biomass on southern Spain beaches. As a feasible alternative for the biomass management, anaerobic co-digestion is proposed in this study. Although the anaerobic digestion of macroalgae barely produced 177 mL of CH4 g−1 VS, the co-digestion with a C-rich substrate, such as the olive mill solid waste (OMSW, the main waste derived from the two-phase olive oil manufacturing process), improved the anaerobic digestion process. The mixture improved not only the methane yield, but also its biodegradability. The highest biodegradability was found in the mixture 1 R. okamurae—1 OMSW, which improved the biodegradability of the macroalgae by 12.9% and 38.1% for the OMSW. The highest methane yield was observed for the mixture 1 R. okamurae—3 OMSW, improving the methane production of macroalgae alone by 157% and the OMSW methane production by 8.6%. Two mathematical models were used to fit the experimental data of methane production time with the aim of assessing the processes and obtaining the kinetic constants of the anaerobic co-digestion of different combination of R. okamurae and OMSW and both substrates independently. First-order kinetic and the transference function models allowed for appropriately fitting the experimental results of methane production with digestion time. The specific rate constant, k (first-order model) for the mixture 1 R. okamurae- 1.5 OMSW, was 5.1 and 1.3 times higher than that obtained for the mono-digestion of single OMSW and the macroalga, respectively. In the same way, the transference function model revealed that the maximum methane production rate (Rmax) was also found for the mixture 1 R. okamurae—1.5 OMSW (30.4 mL CH4 g−1 VS day−1), which was 1.6 and 2.2 times higher than the corresponding to the mono-digestions of the single OMSW and sole R. okamurae (18.9 and 13.6 mL CH4 g−1 VS day−1), respectively.

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Thermophilic Alkaline Fermentation Followed by Mesophilic Anaerobic Digestion for Efficient Hydrogen and Methane Production from Waste-Activated Sludge: Dynamics of Bacterial Pathogens as Revealed by the Combination of Metagenomic and Quantitative PCR Analyses

Applied and Environmental Microbiology ◽

10.1128/aem.02632-17 ◽

2018 ◽

Vol 84 (6) ◽

Cited By ~ 5

Author(s):

Jingjing Wan ◽

Yuhang Jing ◽

Yue Rao ◽

Shicheng Zhang ◽

Gang Luo

Keyword(s):

Microbial Community ◽

Anaerobic Digestion ◽

Activated Sludge ◽

Quantitative Pcr ◽

Methane Production ◽

Bacterial Pathogens ◽

Methane Yield ◽

Metagenomic Analysis ◽

Waste Activated Sludge ◽

Hydrogen Yield

ABSTRACT Thermophilic alkaline fermentation followed by mesophilic anaerobic digestion (TM) for hydrogen and methane production from waste-activated sludge (WAS) was investigated. The TM process was also compared to a process with mesophilic alkaline fermentation followed by a mesophilic anaerobic digestion (MM) and one-stage mesophilic anaerobic digestion (M) process. The results showed that both hydrogen yield (74.5 ml H 2 /g volatile solids [VS]) and methane yield (150.7 ml CH 4 /g VS) in the TM process were higher than those (6.7 ml H 2 /g VS and 127.8 ml CH 4 /g VS, respectively) in the MM process. The lowest methane yield (101.2 ml CH 4 /g VS) was obtained with the M process. Taxonomic results obtained from metagenomic analysis showed that different microbial community compositions were established in the hydrogen reactors of the TM and MM processes, which also significantly changed the microbial community compositions in the following methane reactors compared to that with the M process. The dynamics of bacterial pathogens were also evaluated. For the TM process, the reduced diversity and total abundance of bacterial pathogens in WAS were observed in the hydrogen reactor and were further reduced in the methane reactor, as revealed by metagenomic analysis. The results also showed not all bacterial pathogens were reduced in the reactors. For example, Collinsella aerofaciens was enriched in the hydrogen reactor, which was also confirmed by quantitative PCR (qPCR) analysis. The study further showed that qPCR was more sensitive for detecting bacterial pathogens than metagenomic analysis. Although there were some differences in the relative abundances of bacterial pathogens calculated by metagenomic and qPCR approaches, both approaches demonstrated that the TM process was more efficient for the removal of bacterial pathogens than the MM and M processes. IMPORTANCE This study developed an efficient process for bioenergy (H 2 and CH 4 ) production from WAS and elucidates the dynamics of bacterial pathogens in the process, which is important for the utilization and safe application of WAS. The study also made an attempt to combine metagenomic and qPCR analyses to reveal the dynamics of bacterial pathogens in anaerobic processes, which could overcome the limitations of each method and provide new insights regarding bacterial pathogens in environmental samples.

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Effects of experimental parameters on methane production and volatile solids removal from tomato and pepper plant wastes

BioResources ◽

10.15376/biores.15.3.4763-4780 ◽

2020 ◽

Vol 15 (3) ◽

pp. 4763-4780

Author(s):

Saraí Camarena-Martínez ◽

Juan H. Martínez-Martínez ◽

Adriana Saldaña-Robles ◽

Hector G. Nuñez-Palenius ◽

Rogelio Costilla-Salazar ◽

...

Keyword(s):

Methane Production ◽

Methane Yield ◽

Pepper Plant ◽

Limited Information ◽

Total Solids ◽

Volatile Solids ◽

Vs Removal ◽

Solids Content ◽

Solids Removal ◽

Positive Effect

In Mexico, protected agriculture generates large amounts of tomato and pepper plants residues (TPW and PPW, respectively). Given the limited information on methane production from anaerobic digestion of these wastes, this study aimed to determine the effects of the substrate/inoculum (S/I) ratio, temperature, and total solids content on methane production and volatile solids (VS) removal by two subsequent batch experiments (Experiments A and B). Experiment A was performed to evaluate the substrate/inoculum ratios of 0.5, 1.0, and 2.0 at room temperature (22 ± 4.5 °C). Based on the best methane yield from experiment A, a new experiment was established (Experiment B) using only tomato wastes, where temperature was kept at 29 °C and 39 °C. The total solids content was analyzed depending on the S/I ratio used. For both substrates, an S/I ratio of 0.5 was the most appropriate for methane production. The temperature had a positive effect on volatile solids removal and methane yield. In contrast, the total solids content (% TS) only had a positive effect on methane production. To the authors’ knowledge, this is the first study evaluating the effect of the S/I ratio on methane production from tomato and pepper plant wastes.

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Methane yield enhancement of mesophilic and thermophilic anaerobic co-digestion of algal biomass and food waste using algal biochar: Semi-continuous operation and microbial community analysis

Bioresource Technology ◽

10.1016/j.biortech.2020.122892 ◽

2020 ◽

Vol 302 ◽

pp. 122892 ◽

Cited By ~ 8

Author(s):

Le Zhang ◽

Fanghua Li ◽

Agnès Kuroki ◽

Kai-Chee Loh ◽

Chi-Hwa Wang ◽

...

Keyword(s):

Microbial Community ◽

Food Waste ◽

Algal Biomass ◽

Community Analysis ◽

Continuous Operation ◽

Microbial Community Analysis ◽

Methane Yield ◽

Yield Enhancement ◽

Algal Biochar

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Pretreatment of Animal Manure Biomass to Improve Biogas Production: A Review

Energies ◽

10.3390/en13143573 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3573 ◽

Cited By ~ 3

Author(s):

Meneses-Quelal Orlando ◽

Velázquez-Martí Borja

Keyword(s):

Anaerobic Digestion ◽

Methane Production ◽

Biogas Production ◽

Poultry Manure ◽

Animal Manure ◽

Methane Yield ◽

Operational Parameters ◽

Advantages And Disadvantages ◽

Physical Chemical ◽

Chemical Pretreatments

The objective of this research is to present a review of the current technologies and pretreatments used in the fermentation of cow, pig and poultry manure. Pretreatment techniques were classified into physical, chemical, physicochemical, and biological groups. Various aspects of these different pretreatment approaches are discussed in this review. The advantages and disadvantages of its applicability are highlighted since the effects of pretreatments are complex and generally depend on the characteristics of the animal manure and the operational parameters. Biological pretreatments were shown to improve methane production from animal manure by 74%, chemical pretreatments by 45%, heat pretreatments by 41% and physical pretreatments by 30%. In general, pretreatments improve anaerobic digestion of the lignocellulosic content of animal manure and, therefore, increase methane yield.

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Evaluation on the Methane Production Potential of Wood Waste Pretreated with NaOH and Co-Digested with Pig Manure

Catalysts ◽

10.3390/catal9060539 ◽

2019 ◽

Vol 9 (6) ◽

pp. 539 ◽

Cited By ~ 10

Author(s):

Renfei Li ◽

Wenbing Tan ◽

Xinyu Zhao ◽

Qiuling Dang ◽

Qidao Song ◽

...

Keyword(s):

Anaerobic Digestion ◽

Lignocellulosic Biomass ◽

Methane Production ◽

Biogas Production ◽

Untreated Wood ◽

Wood Waste ◽

Methane Yield ◽

Pig Manure ◽

Naoh Pretreatment ◽

Digestion Technique

Wood waste generated during the tree felling and processing is a rich, green, and renewable lignocellulosic biomass. However, an effective method to apply wood waste in anaerobic digestion is lacking. The high carbon to nitrogen (C/N) ratio and rich lignin content of wood waste are the major limiting factors for high biogas production. NaOH pre-treatment for lignocellulosic biomass is a promising approach to weaken the adverse effect of complex crystalline cellulosic structure on biogas production in anaerobic digestion, and the synergistic integration of lignocellulosic biomass with low C/N ratio biomass in anaerobic digestion is a logical option to balance the excessive C/N ratio. Here, we assessed the improvement of methane production of wood waste in anaerobic digestion by NaOH pretreatment, co-digestion technique, and their combination. The results showed that the methane yield of the single digestion of wood waste was increased by 38.5% after NaOH pretreatment compared with the untreated wood waste. The methane production of the co-digestion of wood waste and pig manure was higher than that of the single digestion of wood waste and had nonsignificant difference with the single-digestion of pig manure. The methane yield of the co-digestion of wood waste pretreated with NaOH and pig manure was increased by 75.8% than that of the untreated wood waste. The findings indicated that wood waste as a sustainable biomass source has considerable potential to achieve high biogas production in anaerobic digestion.

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Methane production from acid hydrolysates of Agave tequilana bagasse: Evaluation of hydrolysis conditions and methane yield

Bioresource Technology ◽

10.1016/j.biortech.2015.01.036 ◽

2015 ◽

Vol 181 ◽

pp. 191-199 ◽

Cited By ~ 33

Author(s):

Jorge Arreola-Vargas ◽

Valeria Ojeda-Castillo ◽

Raúl Snell-Castro ◽

Rosa Isela Corona-González ◽

Felipe Alatriste-Mondragón ◽

...

Keyword(s):

Methane Production ◽

Methane Yield ◽

Agave Tequilana ◽

Hydrolysis Conditions

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Bioelectrochemical Enhancement of Biogenic Methane Conversion of Coal

Energies ◽

10.3390/en11102577 ◽

2018 ◽

Vol 11 (10) ◽

pp. 2577 ◽

Cited By ~ 4

Author(s):

Dong-Mei Piao ◽

Young-Chae Song ◽

Dong-Hoon Kim

Keyword(s):

Methane Production ◽

Methane Conversion ◽

Substrate Inhibition ◽

Hydrolysis Product ◽

Oxygen Demand ◽

Methane Yield ◽

Anaerobic Reactor ◽

Adaptation Time ◽

Biogenic Methane ◽

Inhibition Effect

This study demonstrated the enhancement of biogenic coal conversion to methane in a bioelectrochemical anaerobic reactor with polarized electrodes. The electrode with 1.0 V polarization increased the methane yield of coal to 52.5 mL/g lignite, which is the highest value reported to the best of our knowledge. The electrode with 2.0 V polarization shortened the adaptation time for methane production from coal, although the methane yield was slightly less than that of the 1.0 V electrode. After the methane production from coal in the bioelectrochemical reactor, the hydrolysis product, soluble organic residue, was still above 3600 mg chemical oxygen demand (COD)/L. The hydrolysis product has a substrate inhibition effect and inhibited further conversion of coal to methane. The dilution of the hydrolysis product mitigates the substrate inhibition to methane production, and a 5.7-fold dilution inhibited the methane conversion rate by 50%. An additional methane yield of 55.3 mL/g lignite was obtained when the hydrolysis product was diluted 10-fold in the anaerobic toxicity test. The biogenic conversion of coal to methane was significantly improved by the polarization of the electrode in the bioelectrochemical anaerobic reactor, and the dilution of the hydrolysis product further improved the methane yield.

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