Diseño de torre de humidificación de tiro mecánico forzado mediante la simulación en software libre para determinar parámetros del proceso.

Abstract

In this work, the aim was to identify the fundamental variables in a forced-draft mechanical draft humidification tower process and design it on a laboratory scale. To achieve this, simulation was conducted using the DWSIM software to determine the necessary operating parameters for sizing the tower with the assistance of the QCAD program. The characteristics of the working fluids are crucial in this context, which motivated the measurement of key parameters for both fluids. For the water, which came from the distillation tower in the Unit Operations laboratory at the Technical University of Machala, a temperature of 37°C was recorded using a mercury thermometer. Furthermore, the water flow rate was determined, fixed at 0.0476 liters per second by measuring the time required to fill a 20-liter bucket. As for the air used, it was of atmospheric origin and was at a temperature of 22°C. These measurements provided fundamental data for the development and simulation of the humidification process in the tower. The simulation of the tower's humidification phenomenon was carried out in the DWSIM software, evaluating different models such as NRTL, Wilson, UNIQUAC, and Peng-Robinson to determine which one was most suitable for this simulation. Given the operational conditions in which the primary interaction between water and air is heat transfer with minimal water evaporation, it was concluded that the Peng-Robinson model is the optimal choice due to its simplicity and ability to represent binary systems like water and air. On the design side, the necessary measurements to create the plan in the QCAD program were determined analytically using the data obtained from the humidification process simulation. Regarding the simulation results, the focus was on the amount of heat exchanged between air and water. It was determined that water loses 0.475352 kW of heat during the process, while the air's temperature increased to 27.3226°C after receiving the heat. With the value of heat exchanged, the following design parameters were determined: fan power of 0.25 hp, pump power of 0.5 hp, tower height of 1.60 meters, packing height of 1.28 meters, and cross-sectional area of 0.25 square meters. Data accuracy is critical in the simulation of a forced-draft mechanical draft humidification tower. The Peng-Robinson model stands out for its effectiveness in representing water-air interactions in heat transfer, ensuring reliable results. Additionally, the QCAD software proves to be a valuable tool for creating detailed plans, supporting the successful construction proposal of the laboratory-scale tower. It is expected that the resulting plans can be used for the future construction of a forced-draft mechanical draft humidification tower in the Unit Operations laboratory.