Analysis of Microbial Growth Models for Microorganisms in Chicken Manure Digester

Abstract

Several microorganisms are there in chicken manure (CM) but Salmonella, Cryptosporidium and Escheridia coli are the most identified. Objective of this research includes, carrying out microbial count in the CM substrate for 40 days retention time in a digester, uterlizing kinetic expressions satisfying the process and fitting results obtained with 26 existing microbial growth kinetic models. Results shows that microbes inside the CM slurry, survived for a full period of 37 days divided into 7 days of acclimatization, 23 days of growth and another 7 days of equal rate of death and multiplication. Findings shows that the maximum specific growth rate, , estimated from the basic Monod equation, of the organisms is 0.0076hr^-1 and the half-saturation constant, , is 3.838×〖10〗^8 mg/l which indicates how sufficient the substrate concentration is for the bacteria to feed on. Not all 26 growth kinetic models found in the literature fit the measured experimental data. However, Monod with decay rate, Wayman and Tseng, Han and Levenspiel, Luong and Moser models fit the Monod values after regressing with POLYMATH 6.10 Educational Release.