Resumo

MARTINEZ-DELGADILLO, S. A.; RODRIGUEZ-CRUZ, M.  e  RODRIGUEZ-ROSALES, M. G.. Dispersion model to describe the carbon removal from wastewater in a fixed bed up flow pilot bioreactor with a hexagonal feldspar packing. Rev. Mex. Ing. Quím [online]. 2008, vol.7, n.3, pp.223-228. ISSN 1665-2738.

In this work the modeling of carbon removal from wastewater in a fixed bed up flow pilot bioreactor with a hexagonal feldspar packing was carried out. The performance of a hexagonal feldspar packing was evaluated in an aerated biological pilot reactor. The feldspar packing was obtained by direct extrusion followed by sintering at 1100°C, during 4 hours, conditions at which the highest porosity and specific surface area were obtained. In addition to its easy preparation and low cost, the packing presented chemical resistance to different acids. The biological fixed bed up flow reactor with a total volume of 30.7 L was randomly packed with the hexagonal pieces of feldspar. Dispersion test were performed with a tracer (KCl), to estimate the dispersion number (Nd) in the reactor, with and without aeration. It was found that the dispersion increased due to the aeration and exerts a strong influence on reactor performance. A plug flow reactor model with axial dispersion and Monod kinetic was used to describe the carbon removal (COD) in the reactor at different hydraulic loading rates. The wastewater used during the tests was sampled at the exit of the primary settler of a Mexican wastewater treatment plant, being a mixture of industrial and urban effluents, with a COD = 650 mg/L. Four ascendant flow hydraulic loadings (L) from 1.08 x 10^-4 (m³/s m²) to 4.32 x 10^-4 (m³/s m²) were tested. The COD removal was about 95%, higher than the 85% reported in other studies.

Palavras-chave : dispersion; modeling; feldspar packing; wastewater secondary; treatment.