The Use of Flotation in Fat Recovery and the Pretreatment of Wastewaters from Animal Fat Production
S. Zak1, Z. Pawlak1,2
More details
Hide details
1 University of Technology and Agriculture,
Department of Technology and Chemical Engineering, 85-326 Bydgoszcz,
3 Seminaryjna Street, Poland
2 Utah Department of Health, Environmental Chemistry and Toxicology,
Salt Lake City, 46 Medical Drive, UT 84113, USA
Pol. J. Environ. Stud. 2006;15(3):507–515
This paper presents a method of fat recovery from wastewaters produced in the process of wet rendering. The solution may be used in protein recovery and for pretreatment of wastewaters. The essence of the method is based on dissolved air flotation (DAF) used to separate fats in the 1st stage and protein fractions in the 2nd stage of the process. Its special advantage is the possibility of the direct treatment of mixed wastewaters and silts produced by centrifuges. This method enables the recovery of fats and proteins in a non-rotten form, which permits their further utilization. A flotation system equipped with two separation chambers, pipe reactors, a water saturation station and a control system for optimizing the process were constructed in order to apply the method. The studied method was verified in a real scale installation by treating after-centrifugal wastewater in the volume up to 10.0 m3/day. using the method, the fatty compounds recovery exceeds 85% and suspended proteins are separated from mixed processing wastewaters and after-centrifugal silts.