scholarly journals Evaluation of batch mesophilic anaerobic digestion of raw and trampled llama and dromedary dungs: methane potential and kinetic study

2022 ◽  
Author(s):  
M. J. Fernández-Rodríguez ◽  
J. M. Mancilla-Leytón ◽  
D. de la Lama-Calvente ◽  
R. Borja
Keyword(s):  
Anaerobic Digestion ◽  
Methane Production ◽  
Hydrolysis Rate ◽  
Order Kinetic ◽  
Batch Mode ◽  
First Order ◽  
Volatile Solids ◽  
Order Kinetic Model ◽  
Methane Potential ◽  
Methane Production Rate

AbstractThis research was carried out with the aim to evaluate the anaerobic digestion (AD) of llama and dromedary dungs (both untreated and trampled) in batch mode at mesophilic temperature (35 °C). The biochemical methane potential (BMP) tests with an inoculum to substrate ratio of 2:1 (as volatile solids (VS)) were carried out. The methane yield from trampled llama dung (333.0 mL CH4 g−1 VSadded) was considerably higher than for raw llama, raw and trampled dromedary dungs (185.9, 228.4, 222.9 mL CH4 g−1 VSadded, respectively). Therefore, trampled llama dung was found to be the best substrate for methane production due to its high content of volatile solids as well as its high nitrogen content (2.1%) and more appropriate C/N ratio (23.6) for AD. The experimental data was found to be in accordance with both first-order kinetic and transference function mathematical models, when evaluating the experimental methane production against time. By applying the first-order kinetic model, the hydrolysis rate constants, kh, were found to be 19% and 11% higher for trampled dungs in comparison with the raw dung of dromedary and llama, respectively. In addition, the maximum methane production rate (Rm) derived from the transference function model for trampled llama dung (22.0 mL CH4 g−1 VS d−1) was 83.3%, 24.4% and 22.9% higher than those obtained for raw llama manure and for raw and trampled dromedary dungs, respectively.

scholarly journals Fly ash as stimulant for anaerobic digestion: effect over hydrolytic stage and methane generation rate

2019 ◽  
Vol 80 (7) ◽  
pp. 1384-1391 ◽  
Author(s):  
Lorna Guerrero ◽  
Cristopher Da Silva ◽  
Andrea Barahona ◽  
Silvio Montalvo ◽  
Cesar Huiliñir ◽  
...  
Keyword(s):  
Fly Ash ◽  
Anaerobic Digestion ◽  
Volatile Fatty Acids ◽  
Batch Reactors ◽  
Order Kinetic ◽  
Methane Generation ◽  
First Order ◽  
Secondary Sludge ◽  
Order Kinetic Model ◽  
Methane Potential

Abstract Thermoelectric fly ash was used as a micronutrient source for microorganisms in the anaerobic digestion process of thermally pretreated (1 hour, 120 °C) secondary sludge. The obtained results not only suggest that fly ash improves methane generation in the conversion of volatile fatty acids into methane, but also show a new observation, that the fly ash contributes in the particulate organic solubilization. The maximum methane production rate increased from 6.52 mL/L/d to 22.59 mL/L/d when fly ash was added at a dosage of 150 mg/L in biochemical methane potential tests compared with tests with no added ash. Additionally, the kinetic constants of the hydrolysis of particulate organic matter were obtained in both cases (with and without added ash) in batch reactors using a first-order kinetic model; in the case of no addition, the first-order kinetic parameter was 0.019 ± 0.002 d−1, while with ashes this value increased to 0.045 ± 0.000 d−1. Therefore, the addition of fly ash improves methane generation and hydrolytic kinetics in different orders of magnitude.

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

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.

scholarly journals Pretreatment, Anaerobic Codigestion, or Both? Which Is More Suitable for the Enhancement of Methane Production from Agricultural Waste?

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4175
Author(s):  
Lütfiye Dumlu ◽  
Asli Seyhan Ciggin ◽  
Stefan Ručman ◽  
N. Altınay Perendeci
Keyword(s):  
Anaerobic Digestion ◽  
Methane Production ◽  
Agricultural Waste ◽  
Kinetic Studies ◽  
Antagonistic Effect ◽  
Hydrolysis Rate ◽  
Order Kinetic ◽  
Maximum Enhancement ◽  
Mixing Ratios ◽  
Anaerobic Codigestion

Pretreatment and codigestion are proven to be effective strategies for the enhancement of the anaerobic digestion of lignocellulosic residues. The purpose of this study is to evaluate the effects of pretreatment and codigestion on methane production and the hydrolysis rate in the anaerobic digestion of agricultural wastes (AWs). Thermal and different thermochemical pretreatments were applied on AWs. Sewage sludge (SS) was selected as a cosubstrate. Biochemical methane potential tests were performed by mixing SS with raw and pretreated AWs at different mixing ratios. Hydrolysis rates were estimated by the best fit obtained with the first-order kinetic model. As a result of the experimental and kinetic studies, the best strategy was determined to be thermochemical pretreatment with sodium hydroxide (NaOH). This strategy resulted in a maximum enhancement in the anaerobic digestion of AWs, a 56% increase in methane production, an 81.90% increase in the hydrolysis rate and a 79.63% decrease in the technical digestion time compared to raw AWs. On the other hand, anaerobic codigestion (AcoD) with SS was determined to be ineffective when it came to the enhancement of methane production and the hydrolysis rate. The most suitable mixing ratio was determined to be 80:20 (Aws/SS) for the AcoD of the studied AWs with SS in order to obtain the highest possible methane production without any antagonistic effect.

scholarly journals Effects of Lipase Addition, Hydrothermal Processing, Their Combination, and Co-Digestion with Crude Glycerol on Food Waste Anaerobic Digestion

Fermentation ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. 284
Author(s):  
Xiaojue Li ◽  
Naoto Shimizu
Keyword(s):  
Anaerobic Digestion ◽  
Food Waste ◽  
Methane Production ◽  
Crude Glycerol ◽  
Anaerobic Fermentation ◽  
Gompertz Model ◽  
Volatile Solids ◽  
Methane Potential ◽  
Better Than ◽  
Modified Gompertz Model

To enhance anaerobic fermentation during food waste (FW) digestion, pretreatments can be applied or the FW can be co-digested with other waste. In this study, lipase addition (LA), hydrothermal pretreatment (HTP), and a combination of both methods (HL) were applied to hydrolyze organic matter in FW. Furthermore, the effects of crude glycerol (CG), which provided 5%, 10%, and 15% of the volatile solids (VS) as co-substrate (denoted as CG5, CG10, and CG15, respectively), on the anaerobic digestion of FW were assessed. With an increasing proportion of CG in the co-digestion experiment, CG10 showed higher methane production, while CG15 negatively affected the anaerobic digestion (AD) performance owing to propionic acid accumulation acidifying the reactors and inhibiting methanogen growth. As the pretreatments partially decomposed hard-to-degrade substances in advance, pretreated FW showed a stronger methane production ability compared with raw FW, especially using the HL method, which was significantly better than co-digestion. HL pretreatment was shown to be a promising option for enhancing the methane potential value (1.773 NL CH4/g VS) according to the modified Gompertz model.

scholarly journals Biogas and Methane Potential of Pre-Thermally Disintegrated Bio-Waste

Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3880
Author(s):  
Sylwia Myszograj
Keyword(s):  
Process Parameters ◽  
Alternative Energy ◽  
Biogas Production ◽  
Gompertz Model ◽  
Order Kinetic ◽  
Methane Fermentation ◽  
First Order ◽  
Order Kinetic Model ◽  
Methane Potential ◽  
Kinetics Of

One of the environmental solutions employed in order to achieve circular economy goals is methane fermentation—a technology that is beneficial both for the stabilization and reduction of organic waste and for alternative energy generation. The article presents the results of research aimed at determining the biogas and methane potential of bio-waste which has been pre-thermally disintegrated, and determining the influence of variable process parameters of disintegration on the kinetics of fermentation. A first-order kinetic model was used to describe the fermentation as well as two mathematical models: logistic and Gompertz. It has been found that process parameters such as time (0.5, 1 and 2 h) and temperature (between 55 to 175 °C) have a significant effect on the solubilization efficiency of the bio-waste. The methane fermentation of thermally disintegrated bio-waste showed that the highest biogas potential is characterized by samples treated, respectively, for 0.5 h at 155 °C and for 2 h at 175 °C. The best match for the experimental data of biogas production from disintegrated substrates was demonstrated for the Gompertz model.

scholarly journals Energy Recovery from Anaerobic Digestion of Banana Peels

2019 ◽  
Vol 8 (3) ◽  
pp. 6269-6273
Keyword(s):  
Anaerobic Digestion ◽  
Methane Production ◽  
Biogas Production ◽  
Kinetic Modelling ◽  
Batch Reactor ◽  
Waste Product ◽  
Banana Peel ◽  
Batch Reactors ◽  
Order Kinetic ◽  
First Order

Bananas are tropical fruits mostly eaten in Malaysia. The banana peels are high in organic, and putrescible caused the odour and leachate problem where it has been a dump. In practice, banana peels considered as a waste product that has been combined with municipal solid waste and dumped into the landfills. However, banana peels are bountiful in organic matter and high with moisture content. Thus, it could be a convincing substrate for biogas production through anaerobic digestion so that the major concerns of environmental protection is achieved aside from producing energy in a sustainable way. Therefore, this study was initiated to estimate the ultimate methane yield from the unripe banana peel (UBP) and ripe banana peel (RBP). Besides that, the assessment on the kinetics of the methane production from UBP and RBP is conducted using Modified Gompertz and first-order kinetic modelling. In this study, the anaerobic digestibility of banana peels measured in a batch reactor for 25 days each fed by UBP and RBP. The batch reactors operated at an inoculum to substrate ratio (I/S) of 1.0 and at a mesophilic temperature (37°C). The ultimate methane yields from UBP and RBP digestion were 847.57mLCH4 /gVS and 1405.31mLCH4 /gVS, respectively. The higher bioavailability (in term of COD, and solid) in RBP resulted in the higher methane production rate. Two first-order and modified Gompertz kinetic models were compared for the prediction of organic degradation, and the results indicated that the first-order kinetic model of the RBP fitted the experiment best. It concluded that ripe banana peels are the most preferable feedstock for the anaerobic digestion.

scholarly journals Composting kinetics for mixture of poultry manure and wheat straw based on volatile solids content

2017 ◽  
Vol 1 (9) ◽  
Author(s):  
Ervin Karić ◽  
Ivan Petrić ◽  
Nesib Mustafić
Keyword(s):  
Kinetic Model ◽  
Wheat Straw ◽  
Poultry Manure ◽  
Prediction Performance ◽  
Order Kinetic ◽  
First Order ◽  
Volatile Solids ◽  
Order Kinetic Model ◽  
Mean Differences ◽  
Solids Content

The aim of this study was to determine the composting kinetics for mixture ofpoultry manure and wheat straw based on the volatile solids content.Experimental data was fitted with the first-order and the nth-order kinetic model.The nth-order kinetic model showed better prediction performance than the firstorderkinetic model. For the first-order kinetic model, maximum and meandifferences between experimental and simulation results for the content ofvolatile solids were 5.43% and 3.00%, for the first reactor, and 4.68% and2.12% for the second reactor, respectively, for the nth-order kinetic model,maximum and mean differences were 4.92% and 1.68%, for the first reactor,and 4.09% and 1.42% for the second reactor, respectively.

scholarly journals Preparation and characterization of biodiesel waste-derived biomass for the removal of dye from contaminated water

2020 ◽  
Vol 69 (4) ◽  
pp. 365-375 ◽  
Author(s):  
Alagarasan Jagadeesh Kumar ◽  
Eldon R. Rene ◽  
Rajendra Prasad Singh ◽  
Shasikala Siddharthy ◽  
Jimin Xie ◽  
...  
Keyword(s):  
Ph Effect ◽  
Standard Free Energy ◽  
Contaminated Water ◽  
Standard Entropy ◽  
Order Kinetic ◽  
Batch Mode ◽  
First Order ◽  
Monolayer Adsorption ◽  
Order Kinetic Model ◽  
Pseudo First Order

Abstract Lignocellulosic biodiesel waste of Jatropha husk (JH) was used to develop ZnCl2 activated Jatropha husk carbon (ZAJHC). ZAJHC was applied as an adsorbent for the removal of methylene blue (MB) from contaminated water. Batch mode of adsorption experiments were carried out and the parameters investigated included agitation time, MB concentration (100–180 mg L−1) and adsorbent dose (25–200 mg/50 mL). The adsorption of MB reached equilibrium at 120 min for 100 mg L−1, 140 min for 120 mg L−1 and 160 min for other concentrations tested. Based on the Langmuir isotherm, the monolayer adsorption capacity (Q0) was found to be 500 mg g−1. The kinetic data were also fitted to the pseudo first-order, second-order and intraparticle diffusion models, and the experimental data followed closely the pseudo first-order kinetic model. Thermodynamic parameters such as standard enthalpy (ΔH° 3.86 J mol−1K−1), standard entropy (ΔS° 65.86 J mol−1K−1) and standard free energy (ΔG°) indicated the spontaneous nature of MB adsorption by ZAJHC. The adsorption was found to be endothermic in nature. Alkaline pH was favourable for the adsorption of MB. The pH effect and desorption studies suggest that ion-exchange might be the possible mechanism governing the adsorption process.

scholarly journals Kinetic study of biogas production from anaerobic digestion of vinasse waste

2021 ◽  
Author(s):  
A. Usmani ◽  
B. Pangkumhang ◽  
M. Wongaree ◽  
K. Wantala ◽  
R. Khunphonoi
Keyword(s):  
Anaerobic Digestion ◽  
Biogas Production ◽  
Methanogenic Bacteria ◽  
Order Kinetic ◽  
Microorganism Population ◽  
Volatile Solids ◽  
Biodegradation Process ◽  
Order Kinetic Model ◽  
Time Required ◽  
Two Parameters

Abstract Vinasse, a sugar-ethanol residue, is used as a substrate for biogas production. The characteristics of the vinasse wastewater used were 216,000 mg-COD/L, pH 4.1, and 68.42 mg/L volatile solids. The sludge/wastewater ratio was controlled at about 1.5−2.0, by weight. Biogas production enhancement was studied in relation to two parameters – Citadel BioCat + , a commercial biocatalyst containing a large microorganism population as the methanogenic bacteria source (5 and 10 g), and reaction temparature (30 and 37 °C). Biogas production kinetics were evaluated. The presence of the biocatalyst enhanced biogas production significantly, as well as reducing the time required for anaerobic digestion. The first-order kinetic model described the biodegradation process. The best results were found using 10 g of biocatalyst at 37 °C – i.e., the optimum results based on biogas production potential (A), the highest biogas production rate (U), the minimum biogas production time (λ), and kinetic organic biodegradability constants (k) of 102.71 mL/g-COD, 11.17 mL/g-COD/d, 0.95 day, and 0.0533 day − 1, respectively. COD removal efficiency was up to 60%.

Kinetics of Acid Hydrolysis of Arabinogalactans

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Bright T Kusema ◽  
Chunlin Xu ◽  
Päivi Mäki-Arvela ◽  
Stefan Willför ◽  
Bjarne Holmbom ◽  
...  
Keyword(s):  
Acid Hydrolysis ◽  
Acid Concentration ◽  
Batch Reactor ◽  
Average Molecular Weight ◽  
Hydrolysis Rate ◽  
Order Kinetic ◽  
First Order ◽  
Order Kinetic Model ◽  
Kinetics Of ◽  
Hydrolysis Of

The kinetics of the acid hydrolysis of arabinogalactans (AG) was studied isothermally in a batch reactor. AG was hydrolyzed with hydrochloric acid and the main parameters established were the acid concentration (pH), temperature and AG concentration. The hydrolysis rate increased with the acid concentration (pH) and temperature. Complete hydrolysis of AG to arabinose and galactose was achieved at 90°C and pH 1 without any further degradation of the sugars. A first-order kinetic model including two simultaneous reactions for the formation of arabinose and galactose was successfully fitted to the experimental data. The rate constants and activation energies were calculated from the model. The decrease of the average molecular weight was also explained by the model.

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