Kinetics of biogas production from fermentation broth of wild cocoyam codigested with cow paunch in batch mode
Journal Title: Scientific Journal of Pure and Applied Sciences - Year 2015, Vol 4, Issue 3
Abstract
Mathematical models are useful in solving the stability problems often exhibited by anaerobic digestion process. Kinetics of batch anaerobic digestion of cocoyam waste mixed with cow paunch for biogas production in batch mode was studied for 30 days hydraulic retention time (HRT). Data from cumulative biogas yield obtained during the experimental stages was fitted to C-NIKBRAN mathematical model based on first order reaction which adequately predicted the kinetic behavior of the substrate’s anaerobic biodegradability. The validity of the applied model was also verified through application of the regression model (ReG) (Least Square Method using Excel Version 2003) in predicting the trend of the experimental results. Comparative analysis of Figs. 7-10 show very close alignment of curves which precisely translated into significantly similar trend of data point’s distribution for experimental (ExD), derived model (MoD) and regression model-predicted (ReG) results of cumulative biogas yield. Also, critical analysis of data obtained from experiment and derived model show low deviations on the part of the model-predicted values relative to values obtained from the experiment. This necessitated the introduction of correction factor, to bring the model-predicted cumulative biogas yield to those of the corresponding experimental values. Deviational analysis from strongly indicates that cumulative biogas yield was most reliable based on the associated admissible deviation of the model-predicted cumulative biogas yield from the corresponding experimental values); 9.2% within the pH range. The values of cumulative biogas yield within the highlighted deviation indicates over 90% confidence level for the applied model and over 0.9 effective dependency coefficients (EDC) of cumulative biogas yield on pH, chemical oxygen demand (COD), total viable count (TVC) and total dissolved solids (TDS). Also, deviation of model-predicted cumulative biogas yield from corresponding experimental results indicates a maximum deviation of 7.17%. This translated into over 92% operational confidence for the derived model as well as over 0.92 effective dependency coefficients (EDC) of cumulative biogas yield on pH, chemical oxygen demand, total viable count, and total dissolved solids.
Authors and Affiliations
I. C. E. Umeghalu*| Department of Agricultural and Bioresources Engineering, Nnamdi Azikiwe University, Awka, Nigeria., E. I. U. Nwuba| Department of Agricultural and Bioresources Engineering, Nnamdi Azikiwe University, Awka, Nigeria., D. O. Onukwuli| Department of Chemical Engineering, Nnamdi Azikiwe University, Awka, Nigeria., I. F. Okonkwo| Department of Agricultural and Bioresources Engineering, Nnamdi Azikiwe University, Awka, Nigeria., J. O. Ngini| Department of Agricultural and Bioresources Engineering, Nnamdi Azikiwe University, Awka, Nigeria.
Keywords
Related Articles
- EP ID EP431
- DOI 10.14196/sjpas.v4i3.1853
- Views 489
- Downloads 22
Economic management in the tourism industry in Iran and World
Today, the development of tourism, in all areas, both nationally and regionally, and internationally regarded government planners and managers, and private companies are located. According to the World Tourism Organiza...
Research agenda of Hong Kong teachers’ emotional experiences at work
In recent years, it seems that teachersin Hong Kong feel negatively about their work. To some extent, the negativeemotional experiences may not only affect teachers’ well-being, but also thequality of schooling. Thus,...
Effectiveness of implementing philosophy for children program on students’ creativity
The present research has done to evaluate “the effectiveness of applying philosophic period for kids on the creativity of second grade secondary school, school boys”. After performing Raven IQ test and determination of...
Experimental investigation of the performance of a ground-source heat pump system for buildings heating and cooling
Geothermal heat pumps (GSHPs), or direct expansion (DX) ground source heat pumps, are a highly efficient renewable energy technology, which uses the earth, groundwater or surface water as a heat source when operating i...
Study of export to external barriers of small and medium enterprises (case study of kurdistan province)
Globalization in recent decades due to rapid and complex changescan be found. The international trade and technology to the global market on the component tasks of Governments is increasing due to the complexity of tra...