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The demand for novel and innovative control techniques has increased due to complexity in the process control industries which expect better control with enhanced performance. The optimization of proportional–integral–derivative (PID) controller parameters plays a significant role in the petrochemical and biochemical industries. In all these industries, controlling of continuous stirred tank reactors (CSTRs) is highly deployed whose dynamic characteristics are non‐linear and difficult to control as there is a risk of its temperature deviating from the set point. To have an efficient control, a metaheuristic optimization technique‐based PID, fractional‐order PID controller (FOPID) control evolved using the behaviour of a swarm of birds named coot bird optimization algorithm (CBOA) has been highlighted in this paper. The tuning has been done using the weighted combination of fitness functions, specifically the overshoot (Os) and the settling time (Ts). The simulated results demonstrate the improvement of the time domain response parameters of CBOA tuned PID, FOPID controllers providing an optimum performance when compared to other optimization algorithms and a conventional controller. [ABSTRACT FROM AUTHOR]

Shortages and lack of sources of clean water is a big issue nowadays. This problem happens because of the increment of population that leads to the amount of water usage increases at an alarming rate. Therefore, the sources of water must be explored in order to get a continuous supply of clean water. This paper recommends a new approach to get clean water, which is by purifying the stormwater via progressive freeze concentration (PFC). This method produces a single ice crystal block that contains high purity of water. This paper focuses on the optimization of two operating parameters, which are coolant temperature and operating time. In order to determine the effectiveness of this technology, effective partition constant (K) and concentration efficiency (Eff) were examined. Response surface methodology and central composite design were implemented to find the optimum operating conditions via Statistica software. The best responses for K and Eff obtained were 0.189 and 81.0%, respectively, with the optimum condition at coolant temperature of −8.9°C and operating time at 41.1 min. From the findings, it is proved that PFC has the capability to reduce the concentration of unwanted solute in stormwater and this process has a high potential to be an alternative approach to purify the stormwater. [ABSTRACT FROM AUTHOR]

This paper studies reactive extraction of formic (FA), acetic (AA), propionic (PA) and butyric (BA) acids from aqueous solutions by tri- n-butyl amine/diluent, with particular focus on proper optimization and modeling of extraction equilibria. The uptake capacities of amine/diluent and diluent alone approximate the following order: oleyl alcohol > octyl acetate > diisobutyl ketone and BA > PA > AA ≈ FA. An intrinsic optimization structure has been applied to the description of optimum extraction field of relevant systems, based on analyzing the variation profiles of separation ratio R and synergistic enhancement SE factors through the derivative variation method. We present new solvation molecular models extended-linear solvation energy relation (e-LSER), SPR1 and SPR2 (solvation probability relation), and an extension to group-contribution approach A-UNIFAC (Association-UNIFAC). A-UNIFAC predicts phase equilibria using new group interaction parameters regressed from vapor-liquid equilibrium data. The e-LSER model involves eight descriptors used for expressing solvent effects. By performing SPR1 and SPR2, we are able to scale up the probability range and activation energy of solvation effect. The strength of acid-amine association is calculated with chemodel. e-LSER, A-UNIFAC, SPR and chemodel simulate accurately the observed performance with average deviations inferior to 4.8%, 24.1%, 0.8% and 16.2%, respectively. © 2017 Curtin University and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

One of the most commonly used processes for the removal of acid gases from natural gas is absorption in alkanolamine-based solvents. Operating cost and energy consumption beside environmental cares are the main limiting factors, which lead process designers to select optimum values of sensitive parameters in sweetening plants. This paper summarizes a study that determines values of optimum operating parameters for sweetening a sour gas stream with 5 mol% of CO2 and 0.39 mol% of H2S considering optimum cost and energy consumption. A typical amine sweetening process plant is used to accomplish a steady-state simulation by HYSYS process simulator v8.4 using different amine solutions, i.e. single, mixed, and also activated amines. It also examined some of the important amine process parameters for each amine type such as amine circulation rate, lean amine temperature, corrosion and amine loss considerations. Finally, an economic evaluation is performed by Aspen process economic analyzer to compare operational and total capital costs of processes. It has been revealed that mixture of methyldiethanolamine and dieathanolamine is more applicable due to its higher absorption capacity, lower capital and operational expenditure, and lower costs related to corrosion and amine losses. © 2015 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT In this paper, liquid-liquid equilibrium in decanter of heterogeneous azeotropic distillation is solved by minimizing Gibbs free energy, by using global optimization technique. The azeotropic distillation column is modeled by solving material balance, equilibrium and summation equations, and repulsive particle swarm optimization (RPSO), a stochastic global optimization formalism, is employed to predict stable steady state solution in decanter. To verify the performance of the RPSO algorithm, it is compared with equation solving method for liquid-liquid equilibria by considering two azeotropic systems, namely (1) benzene-ethanol-water and (2) furfural-water. The proposed methodology shows feasibility of the RPSO algorithm in predicting liquid-liquid equilibrium in decanter of heterogeneous azeotropic distillation. © 2013 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]