Evaluación experimental de la eficiencia de remoción de materia orgánica en un reactor de lodos activados a escala piloto, alimentado con agua residual artificial, y con aumento de presión en el sistema.

Abstract

This work evaluates the efficiency of a treatment system in an activated sludge reactor, operated under pressure, located in the Santo Tomas University Aguas Claras Campus from Villavicencio -Colombia. Which was fed by synthetic waste-water proposed, in order to control the characteristics of it, at the entrance of the reactor. The efficiency of the reactor was determined, initially making a characterization of the effluent by an on-site monitoring of the following parameters: Water temperature, pH, Dissolved oxygen and Flow; after this, the independent variables of the investigation were measured, the pressure (3, 5 y 8 psi) , in relation to Henry's law, to determine the solubility of oxygen in the water mixture, the hydraulic retention time (3 , 4 y 6 hours), after which independent variables were measured. , ex situ, such as BOD5, COD and SSV, that is determining the final removal of organic matter in the reactor (efficiency). The temporality of the work covered the months of September to November; in which at the end of September the bioreactor was operated leaving a period of a week for the stabilization and adaptation of the bacteria. Later, the operational runs began during the first week of October, then the sampling and data collection was carried out during the different weeks of the same month and beginning of November, period in which the variations for hydraulic retention time and pressure were determined. as follows: TRH variation weekly, and pressure every two days. In this sense, in addition to the review of secondary information, the current design of the activated sludge system operated under pressure was evaluated and compared to theorical referents of conventional reactors, consequently, aspects to be improved in the treatment were identified, proposing design considerations tending to improve the efficiency of removal the charge, by means of technical information of the treatment system that facilitates the process of maintenance, monitoring and control of the operative conditions. The results in the investigation, are presented by the highest removal efficiency, which was 91.09% for COD and 96.66% for BOD with a pressure of 8 psi, a retention time of 4 hours and a dissolved oxygen of 4.7 mg / L, conversely, the lowest efficiency was found in 53.07% with a pressure of 3 psi, a retention time of 6 hours and an OD concentration of 3.4 mg / L, as well as the operational run in which a removal percentage of 76% was presented with a pressure of 8 psi, a retention time of 6 hours and an OD of 5.8 mg / L respectively. The statistical analysis of variance indicated that there is a significant relationship between the pressure applied to the bioreactor and the efficiency obtained from the process, indicating that at a higher pressure there are better percentages of removal, on the other hand, retention times do not present no significant relationship with the efficiency of the process.