biogas, vitamins, digestion, yeast production, methane fermentation, wastewater


Baking yeast enterprises are a source of environmental pollution by concentrated wastewater. They are usually diluted with water and discharged into sewerage. It is rational to use methane fermentation, which will ensure the removal of pollutants and make the process cost-effective through the use of biogas and digestion. Therefore, it is relevant to study the question of the influence of fermentation parameters on the cleaning efficiency.

The aim of the work is to study the methane fermentation of yeast production effluents in a continuous mode. Objectives: analysis of solving the problem of wastewater treatment of yeast plants, study of the influence of process parameters (dilution rate, addition of cobalt salts) on the efficiency of treatment; gas generation; vitamin production.

Initial COD of effluents 4500 mg O2/dm3, pH 6. Cultivation regime – continuous, dilution rate 4,1·10–3, 6,2·10–3, 8,2·10–3, 12,4·10–3 hours–1. Cleaning efficiency 78,9 %. High values ​​of dilution rate cause overload of activated sludge, which leads to reduced cleaning efficiency. The presence of cobalt also has a depressant effect. A significant amount of biogas (up to 5,2 dm3/dm3) is produced with a high content of methane (up to 85 %), which is an alternative fuel. As the dilution rate increases, the biogas and methane content decrease. With increasing dilution rate from 4,1·10–3 to 12,4·10–3 hours–1, biogas decreased from 1,11 to 0,94 dm3/g CODloading, and from 1,43 to 1,39 dm3/g CODfermentation. Similarly  to the effect on the depth of purification, the inhibitory effect of cobalt on methanogeneration is observed. Digestion is a valuable fertilizer with a significant content of cobalamin vitamins (up to 95 μсg/g). The addition of cobalt salts stimulates the synthesis of vitamins, providing an increase of 26,7 to 51,6 %, improving the ratio between active and inactive forms.


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