A marked enhancement in the production of cell-bound phytase in Pichia anomala was achieved in cyclic fed batch fermentation (47333 UL -1 ) in comparison with that in batch (11569 UL -1 ) and fixed volume fed batch (36911 UL -1 ) fermentations in cane molasses medium. Phytase productivity was sustainable in cyclic fed batch fermentation over seven days, and therefore, this mode of fed batch fer...

Polyhydroxyalkanoates are known to be temporarily stored by microorganisms in activated sludge, especially in anaerobic-aerobic processes. Due to the problems resulted from the disposals of plastic wastes and excess sludge of wastewater treatment plants, the production of polyhydroxyalkanoates by treating activated sludge and determining the effect of process variables were the main issues of t...

Enzymatic reactions can successfully replace complex chemical syntheses using milder reaction conditions and generating less waste. The developed model-based numerical analysis turned out to be a beneficial tool determine the optimal operating policies of multienzymatic reactors. As proved, for such cases, determination Fed-Batch Reactor (FBR) policy results in difficult multiobjective optimiza...

Temperature control of processes that involve the heating and cooling of a closed batch reactor can be a real problem for conventional proportional-integral-derivative (PID) based loop controllers. This paper describes the application of a new industrial advanced process controller. This controller is designed to handle integrating type processes with long dead times and long time constants. Th...

Ammonia inhibition of biohydrogen production was investigated in batch and continuous flow reactors with glucose as a substrate. In batch tests, biohydrogen production rate was highly dependent on pH and ammonia (defined as the sum of NH3 of NH4+ species) concentrations above 2 g N/L. At pH = 6.2, the maximum production decreased from 56 mL/h at 2 g N/L to 16 mL/h at 10 g N/L. At pH = 5.2, prod...

This research examined novel configuration of SBAR in lab-scale for industrial wastewater treatment. To evaluate COD removal efficiency and granules formation of the novel reactor (R1), SBAR system (R2) was operated under similar conditions during the experimental period. R1 and R2 with working volume of 3.6 and 4.5 L were used to cultivate aerobic granules. Both reactors were operated for 4 hr...

Anaerobic sludge from palm oil mill effluent (POME) treatment plant was used as a source of inocula for the conversion of POME into hydrogen. Optimization of temperature and initial pH for biohydrogen production from POME was investigated by response surface methodology. Temperature of 60oC and initial pHof 5.5 was optimized for anaerobic microflora which gave a maximum hydrogen production of 4...

Traditionally polyester production is done in a batch reactor equipped with a separation column for batch distillation. A promising alternative for the intensification of this process is reactive distillation. In this paper, a reactive distillation model is developed for the synthesis of an unsaturated polyester process. The simulation results are compared with the industrial batch reactor outp...

The removal of biological nitrogen from a synthetic wastewater with different ammonium nitrogen concentrations (50 and 100 mgN-NH4/L) by a nitrification and denitrification process using a sequencing batch biofilm reactor (SBBR) with liquid-phase circulation was studied. The system with a total working volume of 4.6 L (3.7 L in the reactor and 0.9 L in the reservoir) treated 2.1 L of synthetic ...

This paper proposes an interval observer for continuous or fed-batch chemical reactors with uncertainties related to both the heat exchange coefficient and the kinetics. The interval observer provides an upper and a lower bound of the state given bounds for the uncertain parameters. The underand over-estimators are state observers for the non-linear reactor model with two positive tuning parame...