2023 AIChE Annual Meeting
(60k) Control of the Absorption so2 with Naoh Solution in Packed Columns Using Aveva Process Simulation
Authors
da Silva, C. A. M., Federal University of São Paulo
Ferreira, P. H. N., Federal University of São Paulo
Sulfur dioxide is an important pollutant, this pollutant originates mainly from the burning of fossil fuels to produce energy. This pollutant needs to be removed as it can cause respiratory problems for humans and contribute to the formation of acid rain. Evaluating the processes for removing SO2 from the flue gas is essential to make them more efficient and at a lower cost. The objective of this work was to perform steady-state and dynamic simulations of a packed tower, using as input data the experimental data of a real spray tower developed by Codolo and Bizzo (2013), in order to evaluate performance and design characteristics of the column. for SO2 removal, using NaOH solution. The main input variables used were gas flows (from 95.1 to 380.5 m3/h), liquid flows (from 800 to 1500 L/h), SO2 concentrations (â 900 ppm), required flow rate of NaOH solution (0.34 to 1.37 kg/h) and volumetric mass transfer coefficient (from 1.52 to 14.2â§10-7 kmol/s m3Pa). The tower was implemented in AVEVA Process Simulation.
Through Steady-state simulation analysis was possible to perform the validation of the experimental data by comparing efficiencies. The simulated model showed excellent correspondence with the experimental data. A correlation coefficient (R2) of 0.998 and 1.000 were obtained for the input data for the spray tower configurations with one nozzle and five spray nozzles, respectively. It was possible to evaluate the pressure drop profile of packed tower and flooding range using the FLEXISADDLES and FLEXIRING packings. The FLEXIRING P1.5" packing demonstrated better flooding factor capacity and lower pressure drop. The dynamic behavior of the SO2 concentration at the open-loop tower output proved to be highly non-linear for several perturbations. Finally, a PI control was implemented to evaluate the dynamic responses of the SO2 concentration in the outlet gas stream due to setpoint changes and disturbances in gas flow and inlet composition. It was possible to obtain a satisfactory control performing adjustments with negligible overshoot for the servo problem and the regulatory control reaching deviations smaller than 0.3%.
Through Steady-state simulation analysis was possible to perform the validation of the experimental data by comparing efficiencies. The simulated model showed excellent correspondence with the experimental data. A correlation coefficient (R2) of 0.998 and 1.000 were obtained for the input data for the spray tower configurations with one nozzle and five spray nozzles, respectively. It was possible to evaluate the pressure drop profile of packed tower and flooding range using the FLEXISADDLES and FLEXIRING packings. The FLEXIRING P1.5" packing demonstrated better flooding factor capacity and lower pressure drop. The dynamic behavior of the SO2 concentration at the open-loop tower output proved to be highly non-linear for several perturbations. Finally, a PI control was implemented to evaluate the dynamic responses of the SO2 concentration in the outlet gas stream due to setpoint changes and disturbances in gas flow and inlet composition. It was possible to obtain a satisfactory control performing adjustments with negligible overshoot for the servo problem and the regulatory control reaching deviations smaller than 0.3%.