Analysis of Possibility of Yeast Production Increase at Maintained Carbon Dioxide Emission Level

Abstract

Main parameters polluting of technological wastewater (dregs from decantation and thicken of the wort) from yeast industry are: nitrogen, potassium and COD. Such wastewater are utilized mostly on agricultural fields. Unfortunately, these fields can only accept a limited amount of wastes. The basic parameter limiting there the amount of wastewater is nitrogen. When capacity of the production is large sewages are often pretreated at an evaporator station. However, due to the fairly high running costs of the evaporator station currently such a solution is applied only to a small amount of wastes (just to meet legal requirements). Replacement of the earth gas with a biomass being supplied to the evaporator station from the agricultural fields will both allow to maintain the carbon dioxide emission level and enable the production growth. Moreover, the biomass growing on the agricultural fields being fertilized with the wastewater coming from the yeast production allows consequently to utilize the greater volume of wastewater. Theoretically, the possible increase in the yeasts production, with maintaining the carbon dioxide emission level, can reach even 70%. Therefore, the solution presented in this paper combines both intensification of the yeasts production and maintaining the carbon dioxide emission level.

Feeding a Membrane-less Microbial Fuel Cell by Mixed Municipal and Industrial Wastewater

“…In the yeast factory the process wastewater (PWW) is produced at the stage of molasses clarification, centrifugation, and vacuum filtering. These wastewater as fertilizer is mainly directed to agricultural fields [70,71]. Figure 1 shows the formations points of the process wastewater in the yeast production.…”

Analysis of the Potential of an Increase in Yeast Output Resulting from the Application of Additional Process Wastewater in the Evaporator Station

“…Taking into account Equations (4) and (19) (and omitting the S 1 stream), the C 9 nitrogen concentration, after directing the n part of the S 4 stream to the ES, can be described as…”

“…Theoretically, when a larger amount of wastewater is routed to process in an ES, the possibility of using larger amounts of process wastewater in AF is feasible, which, in turn, can lead to an increase in the yeast output [18]. Previous studies [18,19] have shown the necessity of a detailed analysis of the wastewater treatment system in yeast factories. The analyzed factory includes a three-stage wastewater treatment system, comprised of an agricultural field (AF), an evaporator station (ES), and a biological wastewater treatment plant (WWTP).…”