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PID control, which is a type of automation, was used to ensure that neutralization takes place in a controlled manner. To determine the PID parameters of the system with the Cohen-Coon tuning method, two different dynamic experiments were carried out for pH and temperature in the first stage, and the transfer function and model parameters were found. In the experiment carried out for the pH variable; time constant (τ) is 59 s, dead time (Ɵ) is 261 s and steady state gain (K) is read from the graph as 14,72, while PID parameters are calculated as KC =0.0375, τI =315.759 s and τD =52.601 s. Likewise, while τ=1402 s., Ɵ= 88 s, and K=-6 were read for the temperature variable, the PID parameters were calculated as KC =6.196, τI =47.23 s, and τD =-19.20 s. The determined controller parameters were used as initial parameters and simulated using the Sfunction block via MATLAB (2007b). The pH set range was coded as 6.5-8.5 and Tset for temperature was coded as 22 °C. As a result of the oscillation observed due to the nature of the PID control parameters that are intended to be controlled, the safe operation of the process and the desired set values are ensured. When the obtained PID controller parameters were applied to the neutralization reaction, the PID control successfully controlled the reactor temperature and pH and eliminated possible hazards in operation. Anti-windup provides better control rather than traditional PID control method. [ABSTRACT FROM AUTHOR]

The phosphorous acid salts are widely used in the industry because of the effective treatment against various fungal diseases encountered in plants. The production process is exothermic and, with high temperatures around 94°C achieved, significant risks were observed in terms of occupational health and safety. Therefore, the aim is to design a control system that will make this production process reliable for human health, economic and ecological damage. For this purpose, studies were carried out to determine the optimum operating mode, heat transfer system, and temperature controller design to prevent a sudden temperature rise. First, the overall heat transfer coefficient between the reactor and the jacket was determined as 51.0930 W/m²°C and, the refrigerant was chosen as cooling water with 1.271 g/s flow rate which is relatively more economical and accessible. The model parameters of the system were determined with a detailed dynamic analysis by giving positive and negative step inputs to the cooling water flow rate and then obtaining model parameters through reaction curve and linear regression methods. By using the obtained model parameters theoretical P, PI and PID parameters were calculated by Cohen Coon and, Ziegler-Nichols approaches, and the success of controller parameters was tested, simulated with the MATLAB Simulink program and lastly, successful temperature control was achieved in the experimental system. [ABSTRACT FROM AUTHOR]

In this work, effects of agitation speed, inoculum ratio, initial substrate concentraion and incubation temperature were investigated for anaerobic biohydrogen production. The most suitable parameters were determined as agitation speed 200 rpm (0 - 200 rpm), microorganism inoculum ratio 1:10 v/v (1:10 - 1:200 v/v), initial substrate concentration 32.4 g COD/L (10.8- 32.4 g COD/L) and temperature 37°C (28-37°C). Under these conditions, 1257 mL H2 production, 17.06 mL H2/g KOI yield and 6.441 mL H2/L maximum H2 production rate had been reached. In the case of an incubation temperature of 37°C, the lag phase was observed to be approximately 6.5 h independent of the initial substrate concentration. The relationship between substrate concentration and product formation was evaluated as reaction order of 1 for elementary reaction rate model, reaction rate constants were calculated as 6.5x10-5 min-1 and 7.92x10-5 min-1 for temperatures of 28°C and 37°C, respectively. Arrhenius model parameters, frequency factor and activation energy were calculated as 9.74x1034 min-1 and 229.20 kJ/mol respectively. Maximum H2 production rates, Michaelis constants (KS) and R2 values were calculated as 11.47 mL H2/L.min, 74.66 mL H2/L.min, 181.9 g COD/L, 447.7 g COD/L and 0.9458, 0.9505 for 28°C and 37°C temperatures, respectively. Using modified Gompertz model, all R2 values were obtained greater than 0.99, maximum H2 production potentials were found as 2.126 L H2/L, 2.777 L H2/L at 28°C and 37°C with 32.4 g COD/L, respectively. Maximum H2 production rate was reached as 15.250 mL H2/L.min at 37°C and 27 g COD/L initial substrate concentration. [ABSTRACT FROM AUTHOR]