scholarly journals Efficiency of Fe3O4 Nanoparticles with Different Pretreatments for Enhancing Biogas Yield of Macroalgae Ulva intestinalis Linnaeus

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 5105
Author(s):  
Ahmed El El Nemr ◽  
Mohamed A. Hassaan ◽  
Marwa R. Elkatory ◽  
Safaa Ragab ◽  
Antonio Pantaleo

In this work, different pretreatment methods for algae proved to be very effective in improving cell wall dissociation for biogas production. In this study, the Ulva intestinalis Linnaeus (U. intestinalis) has been exposed to individual pretreatments of (ultrasonic, ozone, microwave, and green synthesized Fe3O4) and in a combination of the first three mentioned pretreatments methods with magnetite (Fe3O4) NPs, (ultrasonic-Fe3O4, ozone-Fe3O4 and microwave-Fe3O4) in different treatment times. Moreover, the green synthesized Fe3O4 NPs has been confirmed by FTIR, TEM, XRD, SEM, EDEX, PSA and BET. The maximum biogas production of 179 and 206 mL/g VS have been attained when U. intestinalis has been treated with ultrasonic only and when combined microwave with Fe3O4 respectively, where sediment were used as inoculum in all pretreatments. From the obtained results, green Fe3O4 NPs enhanced the microwave (MW) treatment to produce a higher biogas yield (206 mL/g VS) when compared with individual MW (84 mL/g VS). The modified Gompertz model (R2 = 0.996 was appropriate model to match the calculated biogas production and could be used more practically to distinguish the kinetics of the anaerobic digestion (AD) period. The assessment of XRD, SEM and FTIR discovered the influence of different treatment techniques on the cell wall structure of U. intestinalis.

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1703
Author(s):  
Mohamed A. Hassaan ◽  
Ahmed El Nemr ◽  
Marwa R. Elkatory ◽  
Ahmed Eleryan ◽  
Safaa Ragab ◽  
...  

One of the dominant species of green algae growing along the Mediterranean coast of Egypt is Ulva lactuca. Pretreatment can have a major effect on biogas production because hydrolysis of the algae cell wall structure is a rate-limiting stage in the anaerobic digestion (AD) process. The use of ozone, a new pretreatment, to boost biogas production from the green algae Ulva lactuca was investigated in this study. Ozonation at various dosages was used in contrast to untreated biomass, and the effect on the performance of subsequent mesophilic AD using two separate inoculums (cow manure and activated sludge) was examined. The findings indicated that, in different studies, ozonation pretreatment showed a substantial increase in biogas yield relative to untreated algae. With an ozone dose of 249 mg O3 g–1 VS algal for Ulva lactuca, the highest biogas output (498.75 mL/g VS) was achieved using cow manure inoculum. The evaluation of FTIR, TGA, SEM, and XRD revealed the impact of O3 on the structure of the algal cell wall and integrity breakage, which was thus established as the main contributor to improving the biogas production.


2021 ◽  
Vol 17 (4) ◽  
pp. 250-256
Author(s):  
M. Haruna ◽  
O.R. Momoh ◽  
S. Bilal

Biomass is being looked upon as one of the promising renewable energy sources for the future, with growing interest in microalgae conversion into biogas through anaerobic digestion. Recently, the ability of microalgae to treat waste water has doubled its potentials material today. However, in spite of the progress made in that regards, there are still challenges of algae conversion to biofuel, due to the presence of complex cell wall in some algae. Cell wall inhibits bacteria growth during degradation. In this research work 10 grams of Microcoleous vaginatus was treated in an oven at varying temperatures of 70, 75 and 80 oC for an hour, out of which 4 g was measured into 250 ml serum bottle for digestion at mesophilic temperature of 37 oC. Based on the results of proximate analysis, 69%increase in carbohydrate was attained with 72.7 – 148% reduction in moisture content. The biogas yield of untreated sample was 4.36 mLg−1 VS, while, pretreated samples at 70, 75 and 80 ℃ produced 8.39, 9.07 and 9.38 mLg−1VS (volatile solid) of biogas. This  corresponds to 92, 108 and 115% higher than that of untreated samples. However, thermal treatment of M. vaginatus prior to digestion show positive effect on carbohydrate extraction and enhanced biogas and methane yield as well. Therefore, this makes the substrate a good feedstock for biogas production. Keywords: Biomass, pretreatment, thermal, anaerobic digestion, degradation, Microcoleous vaginatus.


Author(s):  
Christian C. Opurum ◽  
Christian O. Nweke ◽  
Christopher E. Nwanyanwu ◽  
Nkemakolam A. Nwogu

This study evaluated the kinetics of diauxic-like pattern of biogas production from energy crops, Sunflower (SF) and Napier grass (NG) with cow dung (CD). The tests were performed in a batch reactor (R) operation for 60 days in R1 - R4 and 53 days in R5 - R8 under mesophilic conditions (24 - 36OC). The characteristics of the tested energy crops suggest that they hold prospects for bioenergy production. The cumulative biogas yield/gVS showed that the best performance was R1 with a biogas yield of 15.17 dm3 (0.046 dm3/gVS) followed by R3, 13.90 dm3 (0.041 dm3/gVS) and R2, 11.01dm3 (0.032 dm3/gVS). A significant difference (P ≤ 0.05) in biogas yield was found in the reactors charged with SF/CD as against SF only. In the reactors that exhibited biphasic biogas production profile, two (2) kinetic parameters, K1 and K2 were determined by the bi-logistic function model. It was observed that the predicted values in the second phase (K2) of biogas production were considerably higher than the first phase (K1) in R2 - R5 as opposed to R6 - R8, which implies more biogas yield in phase 2 than phase 1. The results indicate that anaerobic digestion of SF and NG had a strong positive influence on biogas yield, BP, PR and λ1 but not for λ2. The bi-logistic function model suitably fitted the experimental data with a high correlation coefficient (R2) in the range of 0.986 - 0.997. Based on the kinetic parameters, the bi-logistic function model is well suited for the simulation of diauxic-like biogas production process.


2018 ◽  
Vol 10 (10) ◽  
pp. 3669 ◽  
Author(s):  
Józef Szlachta ◽  
Hubert Prask ◽  
Małgorzata Fugol ◽  
Adam Luberański

The effect of mechanical pre-treatment of nine different agricultural substrates minced to particle sizes of 1.5 mm, 5 mm and 10 mm on biogas and methane yields and fermentation kinetics was investigated. The results showed, that for five of the nine tested substrates (grass, Progas rye, Palazzo rye, tall wheatgrass, beet), a higher biogas production was obtained for the degree of fragmentation of 10 mm compared to fragmentation of 5 mm and 1.5 mm. For fragmentation of 5 mm, the highest biogas production was achieved for sorghum silage, Atletico maize and Cannavaro maize—649.80, 735.59 and 671.83 Nm3/Mg VS, respectively. However, for the degree of fragmentation of 1.5 mm, the highest biogas production (510.43 Nm3/Mg volatile solid (VS)) was obtained with Topinambur silage. The modified Gompertz model fitted well the kinetics of anaerobic digestion of substrates and show a significant dependence of the model parameters Hmax (biogas production potential) and Rmax (maximum rate of biogas production) on the degree of substrate fragmentation.


2018 ◽  
Vol 156 ◽  
pp. 03055 ◽  
Author(s):  
Bakti Jos ◽  
Fariha Hundagi ◽  
Rizqi Pindy Wisudawati ◽  
Budiyono ◽  
Siswo Sumardiono

Biogas is a renewable energy which can be used as an alternative source to replace fossil fuels. Recently, the use of energy has become an important issue because the oil sources and natural gas are depleting. Utilization of carica waste to produce biogas can reduce the consumption of commercial energy sources such as kerosene as well as the use of firewood. Biogas is produced by the process of organic material digestion by certain anaerobic bacterial activity in anaerobic digester. In this study we studied the influence of LS-AD and SS-AD methods, the effect of C / N ratio on biogas yield obtained and kinetics of biogas production reaction. The study was conducted by making a total solid variation of 7%, 9%, 11%, 13%, 19%, 21%, 23% and C/N ratio 25 and 30. The study started with carica waste collection process and examination of the total composition of solids and water content. Thereafter, calculation and determination of variation of C / N ratio by mixing the substrate with inoculum and urea into the reactor. Observe the volume of biogas produced every two-day intervals. The highest biogas production rate of 1.7825 ml/g TS day was obtained from carica solid waste variable by liquid state anaerobic disgestion and C/N 25.


2020 ◽  
pp. 1-12
Author(s):  
Katarzyna Bernat ◽  
Magdalena Zaborowska ◽  
Katarzyna Goryszewska

Respirometric tests, carried out in OxiTop system, were used to determine biogas production (BP) from two waste materials, willow bark residue (W) from the chemical industry and brewer’s spent grain (BSG) from the brewing industry. Moreover, the kinetics of BP and the loss of organic compounds (expressed as COD) were investigated. In this investigation, W and BSG were used both in their unchanged forms and after mechanical pretreatment (grinding to a diameter of 1 mm) (W_G and BSG_G). The initial organic load in the bioreactors was 4 kg OM/m3. The BP from W was 154.1 dm3/kg DM (166.6 dm3/kg OM), and from BSG, it was 536.9 dm3/kg DM (559.5 dm3/kg OM). This probably resulted from the fact that the content of lignin that was hard to biodegrade was higher in W than in BSG. Mechanical pretreatment increased BP from W_G to 186.7 dm3/kg DM (201.9 dm3/kg OM), and from BSG_G to 564.0 dm3/kg DM (588.7 dm3/kg OM). The net biogas yield from W and BSG increased by 17% (35 dm3/kg OM) and 5 % (29 dm3/kg OM), respectively. The kinetic coefficient of BP (kB) and the rate of BP (rB) of W were lower than those of BSG. Mechanical pretreatment increased the kB and rB of biogas production from both waste materials.


Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3880
Author(s):  
Sylwia Myszograj

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.


2015 ◽  
Vol 4 (1) ◽  
pp. 55-63 ◽  
Author(s):  
Ganiyu Kayode Latinwo ◽  
Samuel Enahoro Agarry

This work investigated the effect of plantain peels as co-substrate in the anaerobic digestion of cow dung for efficient and high biogas production. The biogas experiments were carried out in two different 5 L anaerobic digesters and incubated for 40 days at ambient mesophilic temperatures (28 oC to 34 °C). The results showed that co-digestion of cow dung with plantain peels as co-substrate reduced start-up time for biogas generation and increased biogas yield by 18% as compared to cow dung alone. Peak biogas production was obtained for both digesters at pH of 6.7 and 6.9 as well as temperature of 29 and 30oC, respectively. Modelling study revealed that exponential plot simulated better in both ascending and descending limb than the linear plot the biogas production rates in biogas production from cow dung co-digested with plantain peels and cow dung alone, respectively. Logistic growth model and modified Gompertz plot showed better correlation of cumulative biogas production than exponential rise to maximum plot. These results show that biogas production can be enhanced efficiently through co-digestion process.


Processes ◽  
2019 ◽  
Vol 7 (9) ◽  
pp. 600 ◽  
Author(s):  
Sagor Kumar Pramanik ◽  
Fatihah Binti Suja ◽  
Mojtaba Porhemmat ◽  
Biplob Kumar Pramanik

A large quantity of food waste (FW) is generated annually across the world and results in environmental pollution and degradation. This study investigated the performance of a 160 L anaerobic biofilm single-stage reactor in treating FW. The reactor was operated at different hydraulic retention times (HRTs) of 124, 62, and 35 days under mesophilic conditions. The maximum biogas and methane yield achieved was 0.934 L/g VSadded and 0.607 L CH4/g VSadded, respectively, at an HRT of 124 days. When HRT decreased to 62 days, the volatile fatty acid (VFA) and ammonia accumulation increased rapidly whereas pH, methane yield, and biogas yield decreased continuously. The decline in biogas production was likely due to shock loading, which resulted in scum accumulation in the reactor. A negative correlation between biogas yield and volatile solid (VS) removal efficiency was also observed, owing to the floating scum carrying and urging the sludge toward the upper portion of the reactor. The highest VS (79%) and chemical oxygen demand (COD) removal efficiency (80%) were achieved at an HRT of 35 days. Three kinetic models—the first-order kinetic model, the modified Gompertz model, and the logistic function model—were used to fit the cumulative biogas production experimental data. The kinetic study showed that the modified Gompertz model had the best fit with the experimental data out of the three models. This study demonstrates that the stability and performance of the anaerobic digestion (AD) process, namely biogas production rate, methane yield, intermediate metabolism, and removal efficiency, were significantly affected by HRTs.


Energies ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 3571 ◽  
Author(s):  
Li ◽  
Huang ◽  
Liu ◽  
Huang ◽  
Maurer ◽  
...  

Effects of salt on anaerobic digestion are dosage-dependent. As salt is a widely used condiment in food processing, effects of salt are bound to be considered when food waste is digested. In this study, salt addition effects (0, 2, 4, 6, 9, 12 g∙L−1) on biogas and methane yields and kinetics of biogas production were researched. Meanwhile, component characteristics (food waste featured in carbohydrate, protein and fat, respectively) and fermentation concentrations (5 and 8 gVS∙L−1) were also taken into consideration. Results showed that 2–4 g∙L−1 salt addition was the optimal addition dosage for AD systems as they not only have the maximum biogas and methane yields, but also the maximum vs. removal in most cases. Also, according to the results of a modified Gompertz model, which is used to predict biogas and methane production rates, suitable salt addition can accelerate biogas production, improving the maximum biogas production rate (Rmax). Factorial design (2 × 2) proved that interaction of salt and fermentation concentrations was significant for food waste featured with carbohydrate and with protein (p <0.05). High salt addition and fermentation concentration can break the AD system when the feeding material was food waste featured with carbohydrate, but for food waste featured with protein, interaction of fermentation concentrations and salt addition can alleviate inhibition degrees.


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