Biokinetics in acidogenesis of highly suspended organic wastewater by adenosine 5′ triphosphate analysis

Abstract

In this paper, we pointed out the problems of using conventional volatile suspended solids (VSS) and chemical oxygen demand (COD) to evaluate biokinetic coefficients, especially for the treatment of highly suspended organic wastewater. We also introduced a novel approach to evaluate biokinetic coefficients by measurement of adenosine 5'-triphosphate (ATP) of microorganisms. The concept of using ATP analysis in biokinetic evaluations with highly suspended wastewater was shown to be effective. This study also showed that the conventional VSS and COD methods were strongly affected by incoming suspended organics in the wastewater and by biokinetics of microorganisms. A cheese-processing wastewater was used in evaluating the biokinetics of mesophilic acidogens. The concentration of COD and total suspended solids in the wastewater was 63.3 g/L and 12.4 g/L, respectively. The TSS was 23.6% of total solids concentration. A high ratio of VSS to total suspended solids of 96.7% indicated that most of the suspended particles were organic materials. Lactose and protein were the major organic components contributing COD in the wastewater, and a total of 94.2% of the COD in the wastewater was due to the presence of lactose and protein. Two different physiological conditions where the maximum rates of acetate and butyrate production occurred were tested. These were pH 7 (condition A for acetate production) and pH 7.3 (condition B for butyrate production) at 36.2C, respectively. Based on the molecular structures of the major organic substances and microbial ATP analysis, the residual substrate and microbial concentrations were stoichiometrically converted to substrate COD (SuCOD) and microbial VSS (MVSS), respectively, using correlation coefficients reported previously. These SuCOD and MVSS were simultaneously used to evaluate the biokinetic coefficients using Monod-based mathematical equations. The nonlinear least squares method with 95% confidence interval was used to evaluate biokinetic coefficients. The maximum microbial growth rate, mu(max) and half saturation coefficient, K(s), for conditions A and B were determined to be 9.9 +/- 0.3 and 9.3 +/- 1.0 day(-1) and 134.0 +/- 58.3 and 482.5 +/- 156.5 mg SuCOD/L, respectively. The microbial yield coefficient, Y, and microbial decay rate coefficient, k(d) for conditions A and B were determined to be 0.29 +/- 0.03 and 0.20 +/- 0.05 mg MVSS/mg SuCOD, and 0.14 +/- 0.05 and 0.25 +/- 0.05 day(-1), respectively. Specific substrate utilization rate at condition B was 43.8 +/- 20.6 mg SuCOD/mg MVSS/day, which was 31% higher than that at condition A.

Biotechnological Utilization with a Focus on Anaerobic Treatment of Cheese Whey: Current Status and Prospects

“…Cheese processing effluents were also used to determine the biokinetics of mesophilic acidogens. At pH 7 and temperature 36.2 °C, the maximum microbial growth (μ max ), the half saturation coefficient (K s ), the maximum microbial growth rate (Y) and the microbial decay rate (K d ) were calculated to be 9.9 days , correspondingly [2,129]. Ghaly [78], used an UAR in order to investigate the effects of a two stage AD, with and without control of pH at the methanogenesis stage.…”

Group‐specific primer and probe sets to detect methanogenic communities using quantitative real‐time polymerase chain reaction

“…Anaerobiosis of organics involves a consortium of several groups of microorganisms and is based on a series of reactions, the slowest of which determines the overall efficiency of the process (Yu et al, 2002). In anaerobiosis, methanogens play a key role in stabilizing pollution load by participating in the terminal step, methanogenesis.…”

Correlation of microbial mass with ATP and DNA concentrations in acidogenesis of whey permeate

“…Acidogens play a key role in converting the suspended organic materials to various organic acids, hydrogen, and carbon dioxide, major substrates for methanogens. In this situation, the VSS test can misestimate acidogenic microbial mass because the test can not differentiate between microorganisms and suspended organic particles in the wastewater (Yu et al 2002). Therefore, ways of measuring acidogenic microbial mass other than the VSS test are essential for better comprehension of the acidogenic phase in anaerobic processes.…”

“…Biological systems, either aerobic or anaerobic, can be used in the treatment of whey. However, anaerobic digestion offers several advantages over aerobic process, especially in the treatment of high strength organic wastewaters such as whey: the low energy requirement for process operation, low sludge production rate, and production of methane, a readily available energy source (Speece 1996;Yu et al 2002).…”

“…Among them, ATP and DNA assays have been considered to be the most practical for estimating microbial levels in suspended organic wastewaters and widely applied to biological wastewater treatment processes (Jorgensen et al 1992;Liebeskind and Dohmann 1994;Hwang and Hansen 1998;Yu et al 2002). Both ATP and DNA are ubiquitously present in living cells.…”