TITLE: Gassing of Biosuspensions in Bubble Column and Loop Reactors.

AUTHOR: G. Mueller.

INST. AUTHOR: Stuttgart Univ. (Germany, F.R.). Fakultaet 13 - Verfahrenstechnik.

LANGUAGE: German

PUB.  TYPE: Technical Report

PUB.  COUNTRY: Germany Federal Republic

SOURCE: Department of Energy [DEE],  14 Apr 86,  131p.

NTIS ORDER NO.: DE88770020/INW

ABSTRACT:

In the aereation tanks of biological waste water purification plants, oxygen is consumed in the aerobic metabolism of microorganisms. As a rule, oxygen is supplied by gassing the sludge/water suspension with air.  The parameters determining the gas/liquid transport, i.e. the void gas velocity, bubble size and bubble distribution, were determined using the specific mass transfer coefficient k/sub L/ a/w/sub G/. The coefficient is determined, for the most part, by the aereator characteristics and by the coalescence behaviour of the water/sludge suspension. The influence of these parameters on the optimum reactor height under energy aspects is shown using mathematical models. The findings suggest that the optimum reactor height is not constant but depends on the aereator parameters, the water coalescence characteristics, and the remixing of the liquid phase. (ERA citation 13:004402)

REPORT  NUMBER: NP-8770020