scholarly journals Effect of inoculum to substrate ratio on biogas production of sheep paunch manure

2016 ◽  
Vol 62 (No. 1) ◽  
pp. 8-14 ◽  
Author(s):  
A.A. Lawal ◽  
A.U. Dzivama ◽  
M.K. Wasinda
Keyword(s):  
Biogas Production ◽  
Coefficient Of Determination ◽  
Order Kinetic ◽  
Production Rates ◽  
Exponential Equation ◽  
First Order ◽  
Gompertz Equation ◽  
Volatile Solids ◽  
Substrate Ratio ◽  
Order Kinetic Equation

Sheep paunch manure was anaerobically digested to study the effect of inoculum to substrate ratio on biogas production rates and accumulation. Inoculum to substrate ratios of 1.37, 2.05 and 4.1 were digested in biodigesters labelled R1, R2 and <br /> R3 respectively. Results showed that inoculum to substrate ratio had a significant effect on biogas production rates and accumulation. Biogas production rates increased to peak in the order of R3 (0.30526 Nm<sup>3</sup>/kg volatile solids (VS) days), R2 (0.15308 Nm<sup>3</sup>/kg VS d) and R1 (0.11009 Nm<sup>3</sup>/kg VS d) on the 5<sup>th</sup> day. The biogas production accumulation increased from 0.57195 to 1.46784 Nm<sup>3</sup>/kg VS as the inoculum to substrate ratio increased. The result of regression showed that coefficient of determination values for the linear equation ranged from 0.707 to 0.797, while the exponential equation had higher values that ranged from 0.7718 to 0.9929 showing better simulation. The modified Gompertz equation showed better simulation of the biogas production accumulation than the first order kinetic equation due to its higher coefficient of determination values.

Degradation of 4-nitrophenol using the Fenton process

2000 ◽  
Vol 42 (3-4) ◽  
pp. 155-160 ◽  
Author(s):  
Y.-S. Ma ◽  
S.-T. Huang ◽  
J.-G. Lin
Keyword(s):  
Kinetic Equation ◽  
Nitrogen Concentration ◽  
Order Kinetic ◽  
Fenton Process ◽  
Nitrogenous Compounds ◽  
First Order ◽  
Degradation Rate Constant ◽  
Before And After ◽  
Pseudo First Order ◽  
Order Kinetic Equation

In this study, The Fenton process was applied as a pretreatment method to treat industrial wastewater containing 4-nitrophenol (4-NP). The effect of oxidant dosages on the decomposition of 4-NP and the reaction kinetics were investigated. More than 99% of 4-NP was readily decomposed when the reaction was carried out at oxidant concentrations of 5 mM H2O2 and 5 mg/L Fe2+ for 2 hours. The total nitrogenous compounds and the nitrogen gas evolved, accounted for 88% of the initial nitrogen concentration. However, the maximum DOC removal efficiency was 30.6%; and only 1/3 of 4-NP was mineralized to carbon dioxide by the Fenton process. 4-NP degradation profiles fitted well into a pseudo first-order kinetic equation; degradation rate constant (min-1) of 4-NP increased from 4.3×10-3 to 66.1×10-3 with increasing dosages of H2O2 and Fe2+. In addition, the t value was calculated for studying the significance of simulation by the t-test. It was found that the t value was greater than the value for 99% confidence. This result suggested that the 4-NP decomposition profile could be described by the pseudo first-order kinetic equation. Biodegradability of 4-NP before and after the reaction was 0.018 and 0.594, respectively.

Performance evaluation of anoxic and facultative wastewater stabilization ponds

1996 ◽  
Vol 33 (7) ◽  
pp. 141-145 ◽  
Author(s):  
Muwaffaq M. Saqqar ◽  
M. B. Pescod
Keyword(s):  
Performance Evaluation ◽  
Kinetic Equation ◽  
Simple Model ◽  
Operating Time ◽  
Order Kinetic ◽  
Sediment Depth ◽  
First Order ◽  
Maximum Value ◽  
Wastewater Stabilization Ponds ◽  
Order Kinetic Equation

The performance of anoxic and facultative ponds in Jordan was investigated for 12 months. Calculated values of the first order kinetic equation rate for CBOD removal (KCBOD) has resulted in different KCBOD's for different ponds in the same month, at the same temperature. It is evident that factors other than temperature must influence values of KCBOD. The KCBOD values determined were generally lower than those reported in the literature. The maximum value found was only 0.16 (/day). A pond was emptied after 18 months of operation and sediment was found randomly distributed over the pond area, with a depth ranging from 2 to 6 cm (averaging ≈ 4 cm). A simple model has been established to estimate sediment depth (Hs in cm) in terms of the operating time in months (t).

UV Protectants for the Biopesticide Based on Photostabilization of Ecdysone

2011 ◽  
Vol 183-185 ◽  
pp. 401-405 ◽  
Author(s):  
Hua Nan Guan ◽  
De Fu Chi ◽  
Jia Yu
Keyword(s):  
Ultraviolet Light ◽  
Larvicidal Activity ◽  
Half Life ◽  
Moderate Degree ◽  
Order Kinetic ◽  
Synthetic Compounds ◽  
First Order ◽  
Glass Slides ◽  
Life Values ◽  
Order Kinetic Equation

The ultraviolet protectant (UV protectant) properties of different natural and synthetic compounds were investigated for a biopesticide based on ecdysone. This study examined the photostabilization of ecdysone when exposed to ultraviolet light in the presence of some ultraviolet protectants. Ecdysone solutions with and without UV protectants in methanol were applied onto the surface of glass slides. At particular intervals, the remaining concentration of ecdysone was analyzed by HPLC. Using first-order kinetic equation, the dissipation half-life values (DT50) for the degradation of ecdysone under ultraviolet radiation were obtained. The larvicidal activity was evaluated against the larvae of Martianus dermestoides Chevrolat. It indicated that the addition of congo red, yeast, starch and arabia gum provided moderate degree of photostabilization of ecdysone and that addition of lignin provided the best photostabilization of ecdysone, among these UV protectants studied. Toxicity of the ecdysone with UV protectants was higher to the larvae of M. dermestoides Chevrolat compared to the ecdysone alone as indicated by the lower EC50 value. The dissipation half-life values of ecdysone after irradiation under ultraviolet light and the larvicidal activity suggested that the addition of lignin (in 1:l mol ratio) can provide better photostabilization of ecdysone molecule.

Anaerobic biodegradability of fish remains: experimental investigation and parameter estimation

2015 ◽  
Vol 71 (6) ◽  
pp. 922-928 ◽  
Author(s):  
Andres Donoso-Bravo ◽  
Francoise Bindels ◽  
Patrick A. Gerin ◽  
Alain Vande Wouwer
Keyword(s):  
Biogas Production ◽  
Order Kinetic ◽  
Fish Processing ◽  
First Order ◽  
Recirculating Aquaculture ◽  
Anaerobic Biodegradability ◽  
Sturgeon Species ◽  
Order Kinetic Model ◽  
Fish Remains ◽  
High Level

The generation of organic waste associated with aquaculture fish processing has increased significantly in recent decades. The objective of this study is to evaluate the anaerobic biodegradability of several fish processing fractions, as well as water treatment sludge, for tilapia and sturgeon species cultured in recirculated aquaculture systems. After substrate characterization, the ultimate biodegradability and the hydrolytic rate were estimated by fitting a first-order kinetic model with the biogas production profiles. In general, the first-order model was able to reproduce the biogas profiles properly with a high correlation coefficient. In the case of tilapia, the skin/fin, viscera, head and flesh presented a high level of biodegradability, above 310 mLCH4 gCOD−1, whereas the head and bones showed a low hydrolytic rate. For sturgeon, the results for all fractions were quite similar in terms of both parameters, although viscera presented the lowest values. Both the substrate characterization and the kinetic analysis of the anaerobic degradation may be used as design criteria for implementing anaerobic digestion in a recirculating aquaculture system.

scholarly journals Study on environmental behaviour of fluopyram in different banana planting soil

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jia Zhou ◽  
Shuilian Liang ◽  
Yuanyuan Cui ◽  
Yu Rong ◽  
Jia Song ◽  
...  
Keyword(s):  
Sandy Soil ◽  
Alluvial Soil ◽  
Order Kinetic ◽  
Environmental Behaviour ◽  
First Order ◽  
Degradation Rates ◽  
And Migration ◽  
Agricultural Areas ◽  
Banana Leaf ◽  
Order Kinetic Equation

AbstractFluopyram is commonly used to control banana leaf spot, anthracnose, and scab in tropical agricultural areas. To explore its behaviour in tropical agricultural environments, dissipation, adsorption, and leaching behaviours of fluopyram in three typical banana planting soils were studied. Also, its dissipation and migration capabilities in different regions and different soil types were evaluated. The results showed that the dissipation of fluopyram was in accordance with the first-order kinetic equation in the three banana soils, but the degradation rates were quite different. The degradation half-lives in the Hainan latosol, Yunnan sandy soil, and Fujian Plain alluvial soil were 46.21 days, 36.48 days and 57.76 days, respectively. Fluopyram also exhibited high adsorption and low leachability in the three soils. The Fujian Plain alluvial soil had the highest adsorption capacity for fluopyram, while fluopyram had the low leachability in the Yunnan sandy soil.

scholarly journals Kinetic Study of Biogas Production from Animal Manure and Organic Waste in Semarang City by Using Anaerobic Digestion Method

2021 ◽  
Vol 21 (5) ◽  
pp. 1221
Author(s):  
Fahmi Arifan ◽  
Abdullah Abdullah ◽  
Siswo Sumardiono
Keyword(s):  
Kinetic Model ◽  
Organic Waste ◽  
Biogas Production ◽  
Liquid Waste ◽  
Animal Manure ◽  
Chicken Manure ◽  
Cow Dung ◽  
Order Kinetic ◽  
First Order ◽  
Order Kinetic Model

The biogas fermentation from animal manure and organic waste was investigated with a comparison percentage of raw material used inside the digester with the anaerobic digestion process. Animal manure consists of cow dung and chicken manure, while organic waste consists of tofu liquid waste and cabbage waste. This study used a batch process that was operated at 55 °C incubator temperature for 90 days. The results of experimental data were predicted with a modified Gompertz model and first-order kinetic model. The equation of the modified Gompertz model to predict biogas production was  with  is cumulative production of methane; P∞ = methane production potential; Rm = maximum specific speed methane production; λ = is lag phase period or minimum time to produce biogas; e = math constant (2.7182) and t = biogas production cumulative time. The equation first-order kinetic model was Y = Ym (1-exp(-k). The highest biogas yield was obtained by variable 3 in both kinetic studies compared to 70% cow dung, 15% chicken manure, and 15% tofu liquid waste. Gompertz's kinetic study predicted variable three would produce 3273.20 mL/g of total solid (TS). In comparison, the first-order kinetic model predicted that variable three would produce 3517.95 mL/(g Ts).

scholarly journals Differential Thermal Analysis of Tobacco as a Function of Heating Rate

1977 ◽  
Vol 9 (1) ◽  
Author(s):  
C. O. Tiller ◽  
E. M. Gentry
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Heating Rate ◽  
Characteristic Temperature ◽  
Inert Atmosphere ◽  
Order Kinetic ◽  
First Order ◽  
Reconstituted Tobacco Sheet ◽  
Decomposition Processes ◽  
Order Kinetic Equation

AbstractThe differential thermal analysis of reconstituted tobacco sheet heated at rates of 0.1°C/s to 500°C/s in an inert atmosphere is reported. As the heating rate is increased, the characteristic temperature of each global process observed is increased. Using a non-isothermal first-order kinetic equation, the activation energies and frequency factors are obtained for these bulk decomposition processes

Alkaline electro-hydrolysis pretreatment of rice straw for enhanced biogas production under ambient temperature

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Gopal P. Naik ◽  
Anil K. Poonia ◽  
Parmesh K. Chaudhari
Keyword(s):  
Ambient Temperature ◽  
Rice Straw ◽  
Biogas Production ◽  
Agricultural Waste ◽  
Batch Reactors ◽  
Order Kinetic ◽  
First Order ◽  
The World ◽  
Combined Pretreatment ◽  
Order Kinetic Model

Abstract Biogas production can supplement the renewable energy target of the world. For this abundantly available agricultural waste like wheat and rice straw can be used. Biogas generation using this waste will curb the stubble burning incidences, reduce greenhouse gases, enhance farmer’s income, and strengthen the energy security of many countries. The recalcitrant nature of rice straw is a barrier to its hydrolysis, which is a prerequisite of the anaerobic digestion (AD) process. Alkaline, electro-hydrolysis, and a combination of both pretreatment (alkaline electrohydrolysis) methods are undertaken in the present study. Batch reactors at ambient temperature were used for AD of rice straw at different inoculums to substrate ratios (ISR) of 0.5, 0.75, and 1.0 to observe the effect on biogas/methane yield. Among these, a higher amount of biogas was obtained for ISR of 0.5 in all sets of experiments. The combined pretreatment method yielded biogas of 315.9 mL/gVS (equivalent to methane of 167.4 mL/gVS). For pretreat-ed rice straw by electro-hydrolysis, alkaline, and combined (alkaline and electro-hydrolysis) respectively, the methane yields were 7.03, 18.13, and 49.82% higher than untreated rice straw. The biogas had approximately 53% of methane content. The use of rice straw for biogas production may prove a viable alternative for clean and sustainable energy. In the studies, a first-order kinetic model is found to fit better the experimental results.

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.

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