Diseño e implementación de un sistema de control automático para una torre de rectificación de thinner.

Abstract

An automatic control system was designed and implemented for the rectification tower of the unitary operations laboratory Faculty of Sciences of the ESPOCH. In the development, different technologies for the acquisition and processing of data were investigated so that the system is efficient and stable. The implementation and design of the system were carried out according to the specifications set forth by the unit operations laboratory technician. For which it was necessary: remove the gas burner and replace it with an electrical resistance, perform the temperature and visual control for the sensors located in the first dish of the tower and in the dephlegmator, regulate the time of the process and coordinate it with alarms of alert of beginning, end or errors of the system. The design of the system includes the calculation of the resistance for the system, from the required power, approximate time of operation, it is also necessary to calculate the zero crossing detector circuit for the control of the electrical resistance. For the design of the controller, it was decided to use the experimental method and a PI control algorithm was chosen. The development of the program was through open source software My openlab, through a graphical interface and a block programming language. It is concluded that the implemented system will work with an error of less than 5% according to the tests performed, it was determined that the system presents a variation of + - 1.5 ° C, of the set point; because it does not have cooling. It is advisable to check the condition of the equipment before distillation and follow the instructions for its operation, thus avoiding possible accidents.