Autotrophic denitrification using sulfide and integration with the nitrification process in a single reactor

• Grant number: 08/11559-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: May 01, 2009
• End date: February 29, 2012
• Field of knowledge: Engineering - Sanitary Engineering - Basic Sanitation
• Principal Investigator: Eugenio Foresti
• Grantee: Bruna de Souza Moraes
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 05/51702-9 - Development of combined systems of treatment of residuary waters aimed at removal of pollutants and recovery of energy and of products from the carbon, nitrogen and sulphur cycles, AP.TEM

Abstract

This project has the main objective to evaluate the ability to remove nitrogen from effluent from anaerobic reactor treating domestic sewage in a reactor operated in fed-batch mode, containing immobilized biomass, subject to conditions of intermittent aeration, applying autotrophic denitrification using sulfide present in the effluent and biogas as electron donor. Initially, key aspects of this process will be investigated in the presence of nitrate and nitrite as electron acceptors, for its application in effluents from anaerobic reactors, since gaps in literature are particularly significant with respect to the intrinsic kinetics of this process. For this, differential fixed bed reactors will be fed with synthetic wastewater simulating nitrified effluent, and sulfide will be added as a solution of sodium sulfide. The intrinsic kinetics of autotrophic denitrification using sulfide will be determined for different N/S molar ratios. It is intended to deepen the knowledge about the kinetics of the process and evaluate the influence of the concentration of sulfide in the system. Next, the nitrifying/denitrifying reactor will be operated in fed-batch mode under intermittent aeration. The ability to remove nitrogen will be evaluated, being applied autotrophic denitrification using sulfide as electron donor. This reactor will be inoculated with biomass immobilized in polyurethane foams and will receive synthetic wastewater simulating effluent from anaerobic reactor treating domestic sewage, which presents considerable amount of ammonia and sulfides. This step will test different operational conditions aiming to achieve the best efficiency of nitrogen removal, and will also be assessed the influence of the concentration of sulfide in the system. Later, we intend to verify the conditions favorable to the accumulation of nitrite in the reactor, in order to evaluate the occurrence of autotrophic denitrification via nitrite with the use of sulfide present in the effluent as an electron donor. This research aims to increase knowledge about the autotrophic denitrification using sulfide as electron donor, obtaining information to assist in the implementation of this process in the post-treatment of domestic sewage.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

MORAES, Bruna de Souza. Autotrophic denitrification with sulphide and the use of integration with the process of nitrification in a single reactor. 2012. Doctoral Thesis - Universidade de São Paulo (USP). Escola de Engenharia de São Carlos (EESC/SBD) São Carlos.