scholarly journals Anaerobic digestion of tannery solid waste by mixing with different substrates

2015 ◽  
Vol 49 (2) ◽  
pp. 119-124 ◽  
Author(s):  
SR Basak ◽  
MA Rouf ◽  
MD Hossain ◽  
MS Islam ◽  
T Rabeya
Keyword(s):  
Anaerobic Digestion ◽  
Solid Waste ◽  
Total Solid ◽  
Volatile Matter ◽  
Domestic Sewage ◽  
Gas Production ◽  
Cow Dung ◽  
Optimum Result ◽  
Volatile Solids ◽  
Tannery Solid Waste

The tannery solid waste (fleshing) was collected from Hazaribagh, Dhaka. It has been found that fleshing contains 82.57% volatile matter. Further characterization of fleshing showed that it contains low C/N ratio of 2.64 and high pH of 10.99. These characteristics were not suitable for using fleshing as a substrate for anaerobic digestion. The study has been carried out in different ratio of waste fleshing, domestic sewage and cow dung at total solid 6% concentration. In all the reactors fleshing and domestic sewage were mixed at 1:1 ratio. On the basis of the performance of the reactors it was evident that the reactor which contains 75% fleshing with domestic sewage and 25% cow dung showed optimum result. Under optimum condition volatile solids destruction 52%, specific gas production 0.476 L/g volatile solids feed and methane yield 73% were achieved. DOI: http://dx.doi.org/10.3329/bjsir.v49i2.22006 Bangladesh J. Sci. Ind. Res. 49(2), 119-124, 2014

Rheology of sludge from double phase anaerobic digestion of organic fraction of municipal solid waste

2000 ◽  
Vol 41 (3) ◽  
pp. 51-59 ◽  
Author(s):  
P. Battistoni ◽  
P. Pavan ◽  
J. Mata-Alvarez ◽  
M. Prisciandaro ◽  
F. Cecchi
Keyword(s):  
Anaerobic Digestion ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
Pilot Scale ◽  
Gas Production ◽  
Organic Loading Rate ◽  
Second Phase ◽  
Organic Fraction ◽  
Double Phase ◽  
Long Term Experiment

In this paper experimental results on the anaerobic digestion of sewage sludge and organic fraction of municipal solid waste (OFMSW) by using a double phase process are reported. The long-term experiment has been carried out on a pilot scale plant, performed in different sets of operative conditions, during which granulometric distributions of particles in sludges and rheological properties of sludges were monitored. A significant fluidification of sludge was evidenced in the meso-thermo process, especially taking into account the variation in sludge behaviour from the first to the second phase. In the thermo-thermo process a fluidification higher than that shown in meso-thermo conditions is not observed, this suggesting that better results in terms of sludge conditioning can be obtained in a long time spent in thermophilic anaerobic digestion. Total volatile solids (TVS) and total fixed solids (TFS) become the most important parameters when mathematical modelling is applied to these processes.In the acidogenic phase, hydraulic retention time (HRT) and temperature are used to determine rigidity coefficient (RC), while only temperature is needed for yield stress (YC). Organic loading rate (OLR) and specific gas production (SGP) exert an important role in methanogenic phase description.

scholarly journals Heat Exchanger for Bio-Digester under Thermophilic Range

2019 ◽  
Vol 5 ◽  
pp. 79-88
Author(s):  
Prajwal Sapkota ◽  
Laxman Poudel
Keyword(s):  
Heat Exchanger ◽  
Anaerobic Digestion ◽  
Heat Exchangers ◽  
Heating System ◽  
Gas Production ◽  
Cow Dung ◽  
Digestion Rate ◽  
Digestion Process ◽  
Different Temperatures ◽  
Long Time

Bio-gas has been one of the sources of renewable energy and has been used from long time. It is produced by the anaerobic digestion or decomposition of organic compounds and has different process. The digestion process is carried out by bacteria present in the waste and it is highly dependent on the bacteria which work differently on different temperatures. The rate of anaerobic digestion is highest at hemophilic temperature (55°C). Similarly, it is moderate at mesophilic temperature (35°C) and is lowest at psychrophilic (below 20°C). Thus, to attain the highest digestion rate a thermophilic heating system has beend eveloped. The heating system uses five heat exchangers to heat the influent at digester which is of 35m3 volume, to maintain temperature at 56°C. The volume of bio-gas production from this system which uses cow dung as digestingmaterial is about 28 m3 per day.

scholarly journals Anaerobic digestion of mixed dried fallen leaves by mixing with cow dung

2015 ◽  
Vol 50 (3) ◽  
pp. 163-168 ◽  
Author(s):  
MA Rouf ◽  
MS Islam ◽  
T Rabeya ◽  
Ak Mondal
Keyword(s):  
Anaerobic Digestion ◽  
Raw Materials ◽  
Maximum Yield ◽  
Total Solid ◽  
Cow Dung ◽  
Glass Bottle ◽  
Biogas Yield ◽  
Biogas Reactors ◽  
Biogas Reactor ◽  
Fallen Leaves

An investigation was carried out for the production of biogas from dry fallen leaves. The sample was collected from BCSIR campus of Dhaka in winter. The substrate was mixed leaves mainly mahogany (75%), eucalyptus (10 %) and rain tree (15 %) leaves. The study was carried out by whole leaves and crushed leaves directly followed by aerobic pretreatment at 8% total solid (TS) concentration. The raw materials were fed into two liter capacity glass bottle bio digester on batch basis for 60 days at ambient temperature. Different proportion of substrate and cow dung were mixed to get the optimum mix for maximum yield of biogas. The biogas reactor containing 6% crushed and pretreated leaves mixed with 2% cow dung (on 8% TS basis) gave maximum (0.199 l/g) biogas yield. The biogas yield from leaves without pretreatment was found to be too low (0.0106 l/g) for 8%. The COD reduction, VS reduction and methane composition of two biogas reactors have been determined where biogas yield were relatively higher. The maximum methane content of the biogas was found to be about 69.3%.Bangladesh J. Sci. Ind. Res. 50(3), 163-168, 2015

scholarly journals Kinetic Study on Biogas Production from Cabbage (Brassica oleracea) Waste and Its Blend with Animal Manure Using Logistic Function Model

2021 ◽  
pp. 34-43
Author(s):  
Christian C. Opurum
Keyword(s):  
Anaerobic Digestion ◽  
Kinetic Parameters ◽  
Goodness Of Fit ◽  
Biogas Production ◽  
Logistic Function ◽  
Gas Production ◽  
Cow Dung ◽  
Function Model ◽  
Biogas Yield ◽  
Significant Difference

This research paper aimed to evaluate the kinetics of anaerobic digestion (AD) of mixtures of cabbage waste (CW) with (Poultry dropping (PD) and Cow dung (CD). The study was conducted in 10L bio-digesters for 35 days under mesophilic conditions (25 - 35OC). Logistic function equation was used to simulate the experimental data to test for its goodness of fit and kinetic parameters namely: maximum biogas potential (Pb), the maximum biogas production rate (Rm), and the lag phase duration (λ) were estimated in each treatment. Chemical analysis showed that individual substrates possess characteristics that could support microbial activities in biogas production. The biogas yield in terms of added  volatile solids (VS) in decreasing order was as follows: 0.022, 0.018, 0.017, 0.014, 0.014 and 0.013 dm3/g VS for CW/CD 2:1, CW/PD3:1, CW/CD 1:1, CW alone, CW/PD1:1 and  CW/PD 2:1, respectively. A significant difference (P ≤ 0.05) in biogas yield was recorded in CW/CD 2:1 with 7.19 dm3 (53.29% increase). The kinetic parameters (Pb, Rm, and λ) for CW/CD 2:1 was 7.01 dm3, 1.58 dm3.d, and 2.29 days, respectively. This was followed by CW/PD 3:1 (5.84 dm3); with 24.92% increase in gas production and CW/CD 1:1 (5.42 dm3) with 15.53% increase relative to CW alone, 4.69 dm3. The digesters fed with CW/PD 1:1 and CW/PD 2:1 exhibited inhibitory effects on biogas production, with 7.51 and 2.05% decrease in gas yield, respectively. The logistic function model demonstrated a strong relationship between the experimental and model-predicted data. The high correlation coefficient (R2) ranging between 0.978 - 0.993 is evident. The model proved to be a useful tool in predicting anaerobic digestion and biogas production process.

scholarly journals Effect of yeast addition on the biogas production performance of a food waste anaerobic digestion system

2020 ◽  
Vol 7 (8) ◽  
pp. 200443
Author(s):  
Ming Gao ◽  
Shuang Zhang ◽  
Xinxin Ma ◽  
Weijie Guan ◽  
Na Song ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Food Waste ◽  
Biogas Production ◽  
Gas Production ◽  
Production Performance ◽  
Organic Load ◽  
Control Group ◽  
Volatile Solids ◽  
Volatile Organic ◽  
The Stability

Food waste contains numerous easily degradable components, and anaerobic digestion is prone to acidification and instability. This work aimed to investigate the effect of adding yeast on biogas production performance, when substrate is added after biogas production is reduced. The results showed that the daily biogas production increased 520 and 550 ml by adding 2.0% (volatile solids; VS) of activated yeast on the 12th and 37th day of anaerobic digestion, respectively, and the gas production was relatively stable. In the control group without yeast, the increase of gas production was significantly reduced. After the second addition of substrate and yeast, biogas production only increased 60 ml compared with that before the addition. After fermentation, the biogas production of yeast group also increased by 33.2% compared with the control group. Results of the analysis of indicators, such as volatile organic acids, alkalinity and propionic acid, showed that the stability of the anaerobic digestion system of the yeast group was higher. Thus, the yeast group is highly likely to recover normal gas production when the biogas production is reduced, and substrate is added. The results provide a reference for experiments on the industrialization of continuous anaerobic digestion to take tolerable measures when the organic load of the feed fluctuates dramatically.

Effect of Oil Content on Dry Anaerobic Digestion of Food Waste under Mesophilic Conditions

2015 ◽  
Vol 768 ◽  
pp. 281-288
Author(s):  
Lian Hai Ren ◽  
Yan Bing Huang ◽  
Pan Wang
Keyword(s):  
Anaerobic Digestion ◽  
Food Waste ◽  
Oil Content ◽  
Continuous Fermentation ◽  
Biogas Production ◽  
Removal Rate ◽  
Gas Production ◽  
Composition Analysis ◽  
Volatile Solids ◽  
Dry Anaerobic Digestion

The variations of daily biogas yields, cumulative biogas yields, biogas composition analysis, total solids (TS) and volatile solids (VS) were studied in the process of mesophilic and dry anaerobic digestion of food waste under different oil contents (0%, 2%, 4%, 6%, 8%, 10%) at 35 °C. The gas production raised and then went down with the oil content, followed by 243.14, 245.64, 256.09, 269.25, 276.54, 284.22mL /g TS respectively. The research provided a reference for the pretreatment of food waste in follow-up continuous fermentation. Results showed that the period of the process of mesophilic dry anaerobic digestion under oil content of 0% was the shortest, with the total biogas production of 1275.5mL. During the process of the digestion, methane content of the biogas raised and then went down, up to a maximum of 77.62%. The removal rate of TS and VS in food waste with the oil content of 6% was the highest, obtained as 11.2% and 13.2%, respectively.

Kompogas - A New System for the Anaerobic Treatment of Source Separated Waste

1993 ◽  
Vol 27 (2) ◽  
pp. 153-158 ◽  
Author(s):  
A. Wellinger ◽  
K. Wyder ◽  
A. E. Metzler
Keyword(s):  
Retention Time ◽  
Test Organism ◽  
Total Solid ◽  
Anaerobic Treatment ◽  
Gas Production ◽  
Matter Content ◽  
Dry Matter Content ◽  
Total Solids ◽  
Volatile Solids ◽  
Vegetable Wastes

Fruit, yard and vegetable wastes from source-separated collection may vary in their total solid contents as a function of the season and of the sources of waste, e.g. high amounts of vegetables reduce the dry matter content significantly. A new digester system was developed to treat solid wastes from 15% to 40% total solids. It consisted of a horizontal CSTR-type of reactor with an intermittently operated, hydraulically driven stirrer taking up strong shear forces. Experiments in a pilot plant of 15 m3 net volume demonstrated a good performance at 55° C. With dry wastes of around 40% total solids specific gas production rates of 2.7 m3/m3*d at 40 days retention time up to 3.7 m3/m3*d at 13 days retention time were achieved. Pure vegetable waste gave a specific gas production of 3.5 m3/m3*d at 21 days retention time with a gas yield of 460 Liters per kg volatile solids. First experiments on the hygienizing effect of anaerobic digestion demonstrated that within two days of thermal treatment at 50° to 55°C the test organism Bacteriophage f2 was completely destroyed.

scholarly journals Biogas from slaughter house waste and optimization of the process

2016 ◽  
Vol 51 (3) ◽  
pp. 203-214 ◽  
Author(s):  
MA Rouf ◽  
MS Islam ◽  
T Rabeya ◽  
AK Mondal ◽  
M Khanam ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Stomach Content ◽  
Oxygen Demand ◽  
Gas Production ◽  
Batch Reactors ◽  
Volatile Solid ◽  
Optimum Conditions ◽  
Slaughter House ◽  
Destruction Efficiency ◽  
Volatile Solids

To assess the potential of biogas generation by anaerobic digestion from slaughter house waste (undigested stomach content) and to determine the optimum conditions for biogas generation from the substrate, different proportions of substrate were used in six batch reactors R1, R2, R3, R4, R5 and R6. The reactors were operated with initial volatile solid concentrations of 34.00, 50.80, 67.20, 51.60, 48.10 and 63.36 g/l and corresponding specific gas production obtained was 0.258, 0.200, 0.160, 0.270, 0.201 and 0.170 l/g respectively. The volatile solids (VS) destruction efficiency was 31.71%, 29.15%, 28.26%, 32.29%, 30.56 and 29.08% as well as chemical oxygen demand (COD)  reduction achieved in the test reactors were 40.31%, 44.44%, 49.40%, 53.24%, 48.55% and 51.26% in R1, R2, R3, R4, R5 and R6 respectively. Methane yield in different reactors varied from 72% to 76%. The optimum mix for generation of biogas from the substrate was 75% slaughter waste mixed with 25% cow dung.Bangladesh J. Sci. Ind. Res. 51(3), 203-214, 2016

scholarly journals BIOGAS FROM CASSAVA PEELS WASTE

Detritus ◽  
2020 ◽  
pp. 100-108
Author(s):  
Felix Aibuedefe Aisien ◽  
Eki Tina Aisien
Keyword(s):  
Anaerobic Digestion ◽  
Sodium Hydroxide ◽  
Biogas Production ◽  
Cow Dung ◽  
Retention Period ◽  
Buffer Solutions ◽  
Volatile Solids ◽  
Agricultural Applications ◽  
Cassava Peels ◽  
Official Methods Of Analysis

The increasing growth of cassava agro-industries in Nigeria has led to the enormous generation of cassava peels waste. The feasibility of generating biogas and biofertilizer for both domestic and agricultural applications from cassava peels waste inoculated with cow dung was investigated. Fresh and stale cassava peels were used in the study. Three pretreatment chemicals such as sodium hydroxide (NaOH), calcium hydroxide (Ca(OH)2 and ammonium chloride (NH4Cl) buffer solutions were used in pretreating the cassava peels and cow dung slurry. Six batch anaerobic biodigesters of 10-litre capacity each were used in this study for 40 days retention period. The pH, temperature, and volumes of biogas and methane produced were monitored and recorded daily. The fertilizer qualities (total solids, volatile solids, % phosphorus, % nitrogen, etc.) of the digester slurry and the digester sludge after 40 days digestion were determined using official methods of analysis of Association of Official Analytical Chemists (AOAC). The results showed that the amount of biogas generated is 2540 cm3/day. The stale cassava peels and cow dung slurry and the use of NH4Cl pretreatment chemical gave the best biogas production and methane yield of 104,961cm3 and 62.3% respectively. The digester sludge from the anaerobic digestion of cassava peels and cow dung showed and demonstrated good biofertilizer qualities.

Sign in / Sign up

Export Citation Format

Share Document