Vondra M., Máša V., Bobák P., 2016, The Potential for Digestate Thickening in Biogas Plants and Evaluation of Possible Evaporation Methods, Chemical Engineering Transactions, 52, 787-792.
Rising number of biogas plants (BGP) is associated with a rising amount of digestate, which is a by-product of biogas production. Liquid digestate (LD) is produced in mechanical separation of digestate, and contains valuable nutrients as well as large amounts of water. Treatment of the LD is thus rather expensive for the plant owners. One of the ways to drain the LD and obtain valuable concentrated nutrients is vacuum evaporation. Vacuum evaporation allows to utilize low-potential waste heat which occurs in excessive amounts in BGP. The potential for digestate thickening is further discussed. This paper also compares specific heat consumption and other selected parameters of three types of industrial evaporators, which may be suitable for the LD thickening. Presented results shows that the proposed model of MSF evaporator has the best thermal performance.
