scholarly journals Effects of Mixing Ratio and Organic Loading Rate of Acid Fermented Food Wastes and Sewage Sludge on the Anaerobic Digestion Process

2006 ◽  
Vol 25 (3) ◽  
pp. 247-256 ◽  
Author(s):  
Chul-Woo Ahn ◽  
Jin-Sik Park ◽  
Seong-Ho Jang
Keyword(s):  
Anaerobic Digestion ◽  
Sewage Sludge ◽  
Loading Rate ◽  
Fermented Food ◽  
Organic Loading Rate ◽  
Food Wastes ◽  
Mixing Ratio ◽  
Organic Loading ◽  
Anaerobic Digestion Process ◽  
Digestion Process

The Characteristics of the Mixed Sludge Supernatant by Mesophilic Two-Phase Anaerobic Digestion Process

2013 ◽  
Vol 295-298 ◽  
pp. 1393-1397
Author(s):  
Qi Wei Liu ◽  
Xiao Yu Zhang
Keyword(s):  
Anaerobic Digestion ◽  
Loading Rate ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Digestion Time ◽  
Two Phase ◽  
Digestion Process ◽  
Acidogenic Phase ◽  
Methanogenic Phase ◽  
Better Than

The mesophilic (35°C) two-phase anaerobic digestion ( TPAD) process was used to treat mixed sludge from primary sedimentation and secondary sedimentation tanks ( 1:3 ). The results show that when HRT is 10 days and organic loading rate is 1.5kgVS/ (m3•d), the upper-liquid COD of methanogenic phase and acidogenic phase increased along with time, but not obviously; The contents oSuperscript textf polysaccharides and proteins in upper-liquid multiplied increased with digestion time, polysaccharides and proteins in acidogenic phase upper-liquid were more than methanogenic phase; The value of CST became larger after being digested by mesophilic two-phase anaerobic digestion, but the dewaterability of sludge in methanogenic phase is better than acidogenic phase.

scholarly journals Enhancing biogas production by anaerobic co-digestion of water hyacinth and pig manure

2017 ◽  
Vol 8 (3) ◽  
pp. 195-199
Author(s):  
Sy Nam Tran ◽  
Ngoc Dieu Hong Le ◽  
Van Thao Huynh ◽  
Huu Chiem Nguyen ◽  
Hoang Viet Le ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Water Hyacinth ◽  
Loading Rate ◽  
Biogas Production ◽  
Pig Manure ◽  
Mixing Ratio ◽  
Anaerobic Digestion Process ◽  
Second Stage ◽  
Digestion Process ◽  
Good For

The characteristics of anaerobic batch co-digestion of water hyacinth (WH) with pig manure (PM) under seven mixing ratio 100%WH; 80%WH : 20%PM; 60%WH : 40%PM; 50%WH : 50%PM; 40%WH : 60%PM; 20%WH : 80%PM and 100%PM were investigated, each treatment was conducted in five replications with daily loading rate at 1 gVS.L-1.day-1. During the anaerobic digestion process of 60 days, maximum biogas production occurred in two periods, the first stage from 12 - 22 days and second stage from 30 - 35 days. The maximum daily biogas productions from each stage were 17.2 L.day-1 and 15.1 L.day-1, respectively. The cumulative biogas production varied between 60 L (100%PM) and 360 L (60%WH : 40%PM). The results showed that the biogas yields of co-digestion 40 - 80%WH were higher from 34.6 to 56.1% in comparison with 100%PM and from 109 to 143% in comparison with 100%WH. When mixing with WH, treatments were received more methane and the methane contents were higher than 45% (v/v) that good for energy using purposes. Nghiên cứu được thực hiện nhằm khảo sát khả năng gia tăng lượng khí sinh học khi tiến hành đồng phân hủy yếm khí lục bình (WH) và phân heo (PM) ở các tỉ lệ phối trộn khác nhau gồm 100%WH; 80%WH : 20%PM; 60%WH : 40%PM; 50%WH : 50%PM; 40%WH : 60%PM; 20%WH : 80%PM và 100%PM. Các nghiệm thức được nạp lượng nguyên liệu là 1 gVS.L-1.ngày-1 và bố trí lặp lại 5 lần. Theo dõi quá trình phân hủy của các nghiệm thức trong 60 ngày ghi nhận có 2 khoảng thời gian lượng khí sản sinh nhiều nhất - giai đoạn 1 từ ngày 12 đến 22, giai đoạn 2 từ ngày 30 đến 35. Lượng khí sản sinh cao nhất tương ứng trong mỗi giai đoạn là 17.2 L.ngày-1 và 15.1 L.ngày-1. Lượng khí tích lũy trong suốt thời gian thí nghiệm ghi nhận thấp nhất ở nghiệm thức 100%PM đạt 60 L, và cao nhất ở nghiệm thức 60%WH : 40%PM đạt 360 L. Năng suất khí sinh ra của các nghiệm thức phối trộn lục bình từ 40 đến 80% cao hơn từ 34,6 đến 56,1% so với nghiệm thức 100%PM và cao hơn từ 109% đến 143% so với nghiệm thức 100%WH. Hàm lượng mê-tan sinh ra từ các nghiệm thức có phối trộn lục bình ổn định trong khoảng > 45% đảm bảo nhiệt lượng cho nhu cầu sử dụng năng lượng.

Impact of organic loading rate and reactor design on thermophilic anaerobic digestion of mixed supermarket waste

2021 ◽  
Vol 123 ◽  
pp. 52-59
Author(s):  
L. Megido ◽  
L. Negral ◽  
Y. Fernández-Nava ◽  
B. Suárez-Peña ◽  
P. Ormaechea ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Loading Rate ◽  
Reactor Design ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Thermophilic Anaerobic Digestion

Effect of organic loading rate on anaerobic digestion of thermally pretreated Scenedesmus sp. biomass

2013 ◽  
Vol 129 ◽  
pp. 219-223 ◽  
Author(s):  
C. González-Fernández ◽  
B. Sialve ◽  
N. Bernet ◽  
J.P. Steyer
Keyword(s):  
Anaerobic Digestion ◽  
Loading Rate ◽  
Organic Loading Rate ◽  
Organic Loading

Liquefaction and methanization of solid and liquid coffee wastes by two phase anaerobic digestion process

2003 ◽  
Vol 48 (6) ◽  
pp. 255-262 ◽  
Author(s):  
E. Houbron ◽  
A. Larrinaga ◽  
E. Rustrian
Keyword(s):  
Anaerobic Digestion ◽  
Wash Water ◽  
Organic Loading Rate ◽  
Two Phase ◽  
Experimental Conditions ◽  
Coffee Pulp ◽  
Anaerobic Digestion Process ◽  
Digestion Process ◽  
Working Volume ◽  
Acidogenic Reactor

This study attempted to investigate the feasibility of volatile fatty acid (VFA) production from coffee pulp hydrolyse, and further to determine the potential of methanization of both the pre-acidified effluent and the coffee wastewater. The experiments were carried out in 2 completely mixed reactors, each one with a working volume of 4 litres. Coffee pulp was used as substrate in the acidogenic reactor and different mixtures of pulper and wash-water and pre-acidified effluent in the methanogenic one. The acidogenic and methanogenic reactors were operated at an organic loading rate of 5 COD g.l-1.d-1 and 0.5 COD g.l-1.d-1. The total, soluble and VFA's effluent COD concentrations of the acidogenic reactor present average values of 57.75, 17.00 and 13.92 g.l-1 respectively. Under these experimental conditions, 23% (COD based) of coffee pulp was hydrolysed with a rate of 1.32 gCOD.l-1.d-1 and the soluble fraction was transformed to VFA's with an acidification efficiency of 82%. Total VFA's concentration reached a value of 13.9 gCOD.l-1, and acetate, propionate, butyrate and valerate represented 52%, 28%, 9% and 11% respectively of the liquid phase COD. In the methanogenic reactor, COD removal and methanization of fresh coffee wastewater, pre-acidified effluent and both combined occur with an efficiency of 85% to 95% respectively, with a characteristic biogas composition of 80% CH4 and 20% CO2. These results show that a humid coffee ‘Beneficio’ processing daily 23 tons of cherry coffee (fresh fruit), equipped with a two stage anaerobic digestion process could generate at least 1,886 CH4 m3.d-1. This represents an increase in methane production by a factor 3 to 5 compared to a ‘Beneficio’ using anaerobic digestion only for the treatment of its wastewater.

Working Parameters Optimization of Hydrolysis-acidogenesis reactor in two stage anaerobic digestion of slaughterhouse Wastewater for Biogas Production

2020 ◽  
Author(s):  
Dejene Tsegaye Bedane ◽  
Mohammed Mazharuddin Khan ◽  
Seyoum Leta Asfaw
Keyword(s):  
Anaerobic Digestion ◽  
Working Conditions ◽  
Retention Time ◽  
Hydraulic Retention Time ◽  
Loading Rate ◽  
Oxygen Demand ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Slaughterhouse Wastewater ◽  
Working Parameters

Abstract Background : Wastewater from agro-industries such as slaughterhouse is typical organic wastewater with high value of biochemical oxygen demand, chemical oxygen demand, biological organic nutrients (Nitrogen and phosphate) which are insoluble, slowly biodegradable solids, pathogenic and non-pathogenic bacteria and viruses, parasite eggs. Moreover it contains high protein and putrefies fast leading to environmental pollution problem. This indicates that slaughterhouses are among the most environmental polluting agro-industries. Anaerobic digestion is a sequence of metabolic steps involving consortiums of several microbial populations to form a complex metabolic interaction network resulting in the conversation of organic matter into methane (CH 4 ), carbon dioxide (CO 2 ) and other trace compounds. Separation of the phase permits the optimization of the organic loading rate and HRT based on the requirements of the microbial consortiums of each phase. The purpose of this study was to optimize the working conditions for the hydrolytic - acidogenic stage in two step/phase anaerobic digestion of slaughterhouse wastewater. The setup of the laboratory scale reactor was established at Center for Environmental Science, College of Natural Science with a total volume of 40 liter (36 liter working volume and 4 liter gas space). The working parameters for hydrolytic - acidogenic stage were optimized for six hydraulic retention time 1-6 days and equivalent organic loading rate of 5366.43 – 894.41 mg COD/L day to evaluate the effect of the working parameters on the performance of hydrolytic – acidogenic reactor. Result : The finding revealed that hydraulic retention time of 3 day with organic loading rate of 1,788.81 mg COD/L day was a as an optimal working conditions for the parameters under study for the hydrolytic - acidogenic stage. The degree of hydrolysis and acidification were mainly influenced by lower hydraulic retention time (higher organic loading rate) and highest values recorded were 63.92 % at hydraulic retention time of 3 day and 53.26% at hydraulic retention time of 2 day respectively. Conclusion : The finding of the present study indicated that at steady state the concentration of soluble chemical oxygen demand and total volatile fatty acids increase as hydraulic retention time decreased or organic loading rate increased from 1 day hydraulic retention time to 3 day hydraulic retention time and decreases as hydraulic retention time increase from 4 to 6 day. The lowest concentration of NH 4 + -N and highest degree of acidification was also achieved at hydraulic retention time of 3 day. Therefore, it can be concluded that hydraulic retention time of 3 day/organic loading rate of 1,788.81 mg COD/L .day was selected as an optimal working condition for the high performance and stability during the two stage anaerobic digestion of slaughterhouse wastewater for the hydrolytic-acidogenic stage under mesophilic temperature range selected (37.5℃). Keywords : Slaughterhouse Wastewater, Hydrolytic – Acidogenic, Two Phase Anaerobic Digestion, Optimal Condition, Agro-processing wastewater

scholarly journals Adjusting Organic Load as a Strategy to Direct Single-Stage Food Waste Fermentation from Anaerobic Digestion to Chain Elongation

Processes ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 1487
Author(s):  
Vicky De Groof ◽  
Marta Coma ◽  
Tom C. Arnot ◽  
David J. Leak ◽  
Ana B. Lanham
Keyword(s):  
Anaerobic Digestion ◽  
Food Waste ◽  
Loading Rate ◽  
Biogas Production ◽  
Single Stage ◽  
Stirred Tank ◽  
Chain Elongation ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Operating Strategy

Production of medium chain carboxylic acids (MCCA) as renewable feedstock bio-chemicals, from food waste (FW), requires complicated reactor configurations and supplementation of chemicals to achieve product selectivity. This study evaluated the manipulation of organic loading rate in an un-supplemented, single stage stirred tank reactor to steer an anaerobic digestion (AD) microbiome towards acidogenic fermentation (AF), and thence to chain elongation. Increasing substrate availability by switching to a FW feedstock with a higher COD stimulated chain elongation. The MCCA species n-caproic (10.1 ± 1.7 g L−1) and n-caprylic (2.9 ± 0.8 g L−1) acid were produced at concentrations comparable to more complex reactor set-ups. As a result, of the adjusted operating strategy, a more specialised microbiome developed containing several MCCA-producing bacteria, lactic acid-producing Olsenella spp. and hydrogenotrophic methanogens. By contrast, in an AD reactor that was operated in parallel to produce biogas, the retention times had to be doubled when fed with the high-COD FW to maintain biogas production. The AD microbiome comprised a diverse mixture of hydrolytic and acidogenic bacteria, and acetoclastic methanogens. The results suggest that manipulation of organic loading rate and food-to-microorganism ratio may be used as an operating strategy to direct an AD microbiome towards AF, and to stimulate chain elongation in FW fermentation, using a simple, un-supplemented stirred tank set-up. This outcome provides the opportunity to repurpose existing AD assets operating on food waste for biogas production, to produce potentially higher value MCCA products, via simple manipulation of the feeding strategy.

Sign in / Sign up

Export Citation Format

Share Document