Trabajo de grado - Pregrado
Análisis de las características estructurales de los lodos generados a partir de los procesos fisicoquimicos para la recuperación de nutrientes de agua residual municipal
Fecha
2019-08-29Autor
Rivera Velasco, Daniela María
Institución
Resumen
The recovery of nutrients through chemical precipitation from wastewater, is a research field in which it is necessary to investigate in order to develop more efficient processes that allow the use of nitrogen and phosphorus-based compounds applicable to processes agricultural and industrial, thus achieving a more sustainable integral management; In this sense, this grade work was aimed at expanding knowledge and experiences in the treatment of wastewater through the structural characterization of sludge obtained during the chemical precipitation process as an alternative for nutrient recovery.
The project had an experimental stage on a laboratory scale in which the influence of the dose of the precipitating reagent on the structural characteristics of obtained from a nutrient recovery process was evaluated using magnesium chloride (MgCl2) and sodium hydroxide (NaOH) as precipitation reagents, and the influence of hydraulic retention time (HRT) on its characteristics.
The analysis of optical microscopy and SEM-EDS showed that by increasing the dose of MgCl2 as a reagent for precipitation, a greater formation of microcrystals was achieved, mostly in a cubic form, and of particles of different sizes with an amorphous structure, which According to the results of X-ray diffraction, it was associated with the presence of salts such as struvite and hydroxyapatite.
For tests with NaOH as a precipitation reagent, it was found that the precipitation of salts with amorphous structures was promoted, mainly associated with hydroxyapatite; It was also observed that the increase in pH, although it favored precipitation processes, was not reflected in an increase in the size of the particles formed.
Regarding the influence of HRT on the structural characteristics of the particles obtained, the optical microscopy analysis and in contrast to the observations of SEM-EDS showed that the increase in HRT promoted the formation of particles with a more defined morphology, both for Crystal structures like amorphous