Análisis de la concentración de gases contaminantes en las fosas de revisión técnica vehicular de la Empresa Publica Mancomunada de Tránsito de Tungurahua (EPMTT) para el diseño e implementación de un sistema de ventilación

Abstract

In this work, a system of ventilation (extraction) of gases such as carbon monoxide (CO), carbon dioxide (CO2) and air was implemented in the different pits of the vehicle technical inspection center in Tungurahua province, Pelileo canton, where it was possible to verify the concentration of the mentioned gases with the MSA Orion plus equipment that records the contamination of the air inside the pits of CO in ppm and CO2 in percentage of concentration. The measurement was performed during the normal working day of the center, for the determination of the selection parameters of the fan as static pressure and extraction flow, the 6 steps described in the manual of ventilation of Soler and Palau of the year 2012 were followed. In the results it was determined that the ideal extractor fan to remove the flow present in the revision pits is the centrifugal extractor model Bs 700, which has the capacity to move flow rates of 675 m^3/h, as well as a maximum sound emission of 66 dB, this emission is considered for the daily exposure of 8 hours of work that the technicians have during their working day. With the calculated extraction flow rates and the concentration levels of CO and CO2, it was possible to determine the pressure increase in the pipes and the losses through accessories, for the different gases to be evacuated, the SOLID WORKS software was used. The automatic control system of the extractors was designed with photoelectric sensors and an automaton for the independent operation of the 4 extractors, thus ensuring that the gases go to the outside of the pits complying with a free discharge and ensuring that these gases do not re-circulate inward, guaranteeing the designed ventilation system.