Anaerobic acidification of sugar-beet processing wastes: Effect of operational parameters

2011-01-01
Alkaya, Emrah
Demirer, Göksel Niyazi
The objective of this study was to maximize the hydrolysis and acidification of sugar-beet processing wastewater and beet pulp for volatile fatty acid (VFA) production through acidogenic anaerobic metabolism. Experiments were conducted to determine the optimum operational conditions (HRT, waste-mixing ratio and pH) for effective acidification in daily-fed, continuously mixed anaerobic reactors. For this purpose, reactors were operated at 35 +/- 1 degrees C with different combinations of HRT (2-4 days), wastewater-pulp mixing ratios (1:0-1:1, in terms of COD) and pH ranges (5.7-7.5). Increased OLRs, resulting from pulp addition, increased the amount of acidification products (VFAs) which led to relatively low operational pH values (5.7-6.8). In this pH range, methanogenic activity was successfully inhibited and the lowest methane percentages (5.6-16.3%) were observed in the produced biogas. The optimum operational conditions were determined to be 2-day HRT and 1:1 waste mixing ratio (in terms of COD) without external alkalinity addition. These operational conditions led to the highest tVFA concentration (3635 +/- 209 mg/L as H-Ac) with the acidification degree of 46.9 +/- 2.1%.
BIOMASS & BIOENERGY

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Citation Formats
E. Alkaya and G. N. Demirer, “Anaerobic acidification of sugar-beet processing wastes: Effect of operational parameters,” BIOMASS & BIOENERGY, pp. 32–39, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/57215.