A new process which attains both excess sludge reduction and phosphorus recovery has been developed. In this paper, characteristics of sludge solubilization by ozone were investigated in batch experiments with sludge taken from an A/O reactor supplied with synthetic sewage and several real wastewater treatment plants. Then, performance of the new developed process was investigated in a laborato...

polygalacturonase production under different shear stress environments by aspergillus sp. was studied. it was found that the rate of enzyme production in the stirred tank fermentor decreased with increasing the stirrer speed in the range 300-750 rpm. on the other hand, in a split cylinder air-lift fermentor, the rate of polygalacturonase production slightly increased with increasing in air rate...

in this work, mathematical modeling of microbial(trichosporon sp.) biomass production in a stirred tankbioreactor and in an external airlift bioreactor has beeninvestigated. a model based on a tanks-in-seriesmodel without back-flow has been used to simulate theproduction of single cell protein in the external airliftbioreactor under an unsteady condition and withoutoxygen limitation, utilizing ...

Adeno-associated virus vectors (AAV) are reported to have a great potential for gene therapy, however, major bottleneck this kind of therapy is the limitation production capacity. Higher specific AAV vector yield often adherent cell systems compared cells in suspension, and microcarrier-based culture well established anchored on larger scale. The purpose present study was explore how microcarri...

Continuous Stirred Tank Reactor System (CSTR) is a typical chemical reactor system with complex nonlinear dynamic characteristics. There has been considerable interest in its state estimation and real time control based on mathematical modelling. However, the lack of understanding of the dynamics of the process, the highly sensitive and nonlinear behaviour of the reactor, has made difficult to ...

Continuous Stirred Tank Reactor (CSTR) here is considered as a nonlinear process. The CSTR is widely used in many chemical plants. Due to changes in process parameters the accuracy of final product can be reduced. In order to get accurate final product the faults developed in CSTR during the chemical reaction need to be diagnosed. If not, the faults may lead to degrade the performance of the sy...

This paper deals with the nonlinear control of a three-state continuous-stirred tank system (CSTR) using the backstepping technique. A nonlinear state transformation is introduced so that the backstepping technique could be utilized on the transformed system. The backstepping controller is first designed for the nominal CSTR system. Then an augmented backstepping control law is designed for the...

In this contribution we apply the approach of passivity proposed by Ydstie [M. Ruszkowski, V. Garcia-Osorio, and B.E. Ydstie. AIChE Journal, 2005] for physico-chemical processes. The originality of this work lies in the fact we consider a thermodynamically nonlinear consistent model for a continuous stirred tank reactor to built the appropriate Lyapunov function for stabilization purpose. Indee...

spherical with an indented base and of volume less than the parent and this was not varied. Other work has shown (ref. [3]) that sphere. When they are large the dhTerence in shape between two parameters describing the bubbles do vary with bed thickness and and three-dimensinal bubbles is considerable. can be sensitive to its value when it is smal]. Further treatment of al1 the data referred to ...

Stirred tanks and bubble columns are widely used as mixing essels and bioreactors. Average spatial fluid velocity gradients t the level of the eddies or the prevailing shear rate, is an imporant variable in bioreactors but is not easy to characterize. A nowledge of shear rate is essential for at least two main reasons: 1) shear rate influences the average apparent viscosity of nonewtonian fluid...