Analysis and experimental demonstration of forced periodic operation of an adiabatic stirred tank reactor: Simultaneous modulation of inlet concentration and total flow-rate

This paper describes the ozonation process in yarn dyed wastewater using continuous stirred tank reactor with the objective to study the kinetic of COD degradation at various volumetric flow rate (30, 50, 70 ml/min) and ozone concentration (2.70 %, 4.25%, 5.86 % mol/mol). The wastewater which was collected from a yarn dying process located in Surabaya area was pretreated by electrocoagulation prior to ozonation process. The electrocoagulation process was carried out to reduce the color intensity and total suspended solid. The pretreated wastewater was then processed using ozonation for 2.5 hours. The result showed that at various concentration of ozone, maximum COD removal was 90.78% which was achieved at 5.86 %mol/mol of Ozon and volumetric flow rate 50 ml/min. It was found that the degradation process followed the pseudo-first order kinetic model. The obtained pseudo-first order rate constants for volumetric rate of 50 mil/min were 0.0307 min-1, 0.0419 min-1 and 0.053 min-1 for ozon concentration of 2.70 %, 4.25%, 5.86 % mol/mol respectively. The residence time were 41 minutes, 31 minutes and 23 minutes for ozone concentration of 2.70 %, 4.25%, 5.86 % mol/mol respectively. These findings offers an alternative treatment for wastewater containing dyes.

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Conceptual Study of Transesterification of Vegetable Oils in the Continuous-Stirred-Tank Reactor at Unsteady-State and Isothermal Conditions

Malaysian Journal of Fundamental and Applied Sciences ◽

10.11113/mjfas.v17n2.2006 ◽

2021 ◽

Vol 17 (2) ◽

pp. 181-194

Author(s):

Fadzil Noor Gonawan ◽

Azlina Harun Kamaruddin

Keyword(s):

Flow Rate ◽

Enzymatic Reaction ◽

Volumetric Flow Rate ◽

Packed Bed ◽

Stirred Tank ◽

Continuous Stirred Tank Reactor ◽

Stirred Tank Reactor ◽

Tank Reactor ◽

Isothermal Conditions ◽

Continuous Stirred Tank

The continuous-stirred-tank reactor (CSTR) is favorable for bi-phasic enzymatic reaction due to ease of operation, cost-effective and low downtime. Lack of study on the enzymatic reaction in the CSTR has disfavor this type of reactor compared to batch and packed bed. Presently, a simulation was carried out to simulate the behavior of the lipase-catalyzed production of biodiesel by using CSTR at isothermal conditions. The mathematical model incorporated the effect of the kinetic, thermal, and operating parameters. The parameters such as Michaelis constant (Km), inhibition constant (Ki), Gibbs inactivation energy (DelG) and mol flow rate are among determining factors of the course of the reaction. It is suggested that the enzyme with lower , higher , and higher should be chosen for the reaction. In continuous operation in the CSTR, the volumetric flow rate of the substrates and the initial concentration of the feed could be used to control reaction performance as these parameters will determine the total mol or ratio of the substrates in the reactor. Most, importantly, the longer residence time is preferred to achieve higher conversion, however, the volumetric flow rate must not be too low to prevent underperformance of reaction.

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On the steady-state behaviour of the autocatalator model A + 2B⇌3B, B⇌C in a continuous-flow stirred-tank reactor

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1987.0061 ◽

1987 ◽

Vol 411 (1840) ◽

pp. 193-206 ◽

Cited By ~ 10

Keyword(s):

Steady State ◽

Continuous Flow ◽

Exothermic Reaction ◽

Stirred Tank ◽

Inlet Concentration ◽

Bifurcation Diagrams ◽

Stirred Tank Reactor ◽

Tank Reactor ◽

State Behaviour ◽

Steady State Behaviour

The steady-state behaviour of the ‘ autocatalator ’ model A + 2B⇌3B B⇌C in a continuous-flow stirred-tank reactor (CSTR) with flow rate as the bifurcation variable is investigated. It is shown that the model gives rise to a structurally stable singularity provided none of the rate constants is zero and all the species are present in the feed stream. When the inlet concentration of species A is greater than three times that of species C, there exist 14 stable bifurcation diagrams. Some of these bifurcation diagrams contain three different ranges of flow rates in which multiplicity exists. When the inlet concentration of species A is smaller than three times that of C, the organizing centre for the autocatalator is a winged cusp. The unfolding of this singularity gives seven stable bifurcation diagrams, which also exist for the physical system. In this case, the behaviour of the autocatalator is qualitatively the same as that of the classical problem of a single exothermic reaction in a CSTR.

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Coolant flow rate vs. agitator speed as manipulated variables for the temperature control of a continuous stirred tank reactor

Chemical Engineering Science ◽

10.1016/0009-2509(72)85093-0 ◽

1972 ◽

Vol 27 (12) ◽

pp. 2151-2161

Author(s):

H.R. Demo ◽

O.A. Iglesias ◽

I.H. Farina ◽

E. Willis ◽

M. De Santiago

Keyword(s):

Temperature Control ◽

Flow Rate ◽

Coolant Flow ◽

Stirred Tank ◽

Coolant Flow Rate ◽

Continuous Stirred Tank Reactor ◽

Stirred Tank Reactor ◽

Tank Reactor ◽

Continuous Stirred Tank

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Improving the Performance of a Continuous Stirred Tank Reactor Using Moving Horizon State Estimation and Model Predictive Control

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.403-408.3454 ◽

2011 ◽

Vol 403-408 ◽

pp. 3454-3460

Author(s):

Fazlollah Armoon ◽

Hooshang Jazayeri-Rad

Keyword(s):

Model Predictive Control ◽

State Estimation ◽

Predictive Control ◽

Stirred Tank ◽

Continuous Stirred Tank Reactor ◽

Inlet Concentration ◽

Product Concentration ◽

Stirred Tank Reactor ◽

Tank Reactor ◽

Continuous Stirred Tank

Since chemical reactors are utilized to produce specific and valuable products, concentration of products should be regulated at a specified level. As a disturbance input, a change in the inlet concentrations can vary the product concentration. So, in order to regulate the product concentration, the inlet concentrations and the product concentration should be measured. However, measurement of concentration encounters some problems such as high cost and time delay. For compensation of these failures, estimation of concentration has been proposed. In this work, the inlet concentration and the product concentration of a continuous stirred-tank reactor (CSTR) are estimated based on the moving horizon state estimation (MHSE), and the product concentration is regulated based on the model predictive control (MPC). Simulation results indicate that the proposed strategy improves the performance of the CSTR compared with the method in which the inlet concentration is not estimated.

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