Influence of influent concentration and feed time on biohydrogen production in an ASBBR with agitation treating sucrose based wastewater

Author(s)

Mehdi El Manssouri

• Document type: Master's Dissertation
• Press: São Carlos.
• Institution: Universidade de São Paulo (USP). Escola de Engenharia de São Carlos (EESC/SBD)
• Defense date: 2012-03-23

Examining board members

José Alberto Domingues Rodrigues; Luiz Olinto Monteggia; Marcelo Zaiat

• Advisor: José Alberto Domingues Rodrigues

Abstract

A mechanically stirred anaerobic sequencing batch reactor containing immobilized biomass treated sucrose-based synthetic wastewater to produce biohydrogen. The system was inoculated with sludge from an anaerobic methanogenic reactor. The following have been assessed: production of biohydrogen, yield per applied and removed load, reactor stability and efficiency under different applied volumetric organic loads applied (AVOL - 9.0, 12.0, 13.5, 18.0, 18. 0 and 27.0 kgDQO/\'M POT.3\'.d), which were modified according to the influent concentration (3600 and 5400 mgDQO/L) and cycle time (4, 3 and 2 h). The reactor\'s ability to remove organic matter (COD) remained stable and close to a value of 18%, and the system shows good ability to convert carbohydrates (sucrose) which remained between 83 and 97% during the operation. There was a decrease in removal performance of the reactor with increasing applied organic load, and furthermore, increasing influent concentration (at constant cycle length) and cycle lengths (at constant influent concentrations) resulted in lower conversion efficiencies. Under all conditions, as organic load increased there was a predominance of acetic, propionic and butyric acid, as well as ethanol. The highest concentration of bio-hydrogen in the biogas (24-25%) was achieved at conditions with AVOL of 12.0 and 13.5 kgDQO/\'M POT.3.d, the highest daily production rate (0.139 mol/d ) was achieved at AVOL of 18.0 kgDQO/\'M POT.3\'.d, and the highest production yields per removed and applied load were 2.83 and 3.04 mol \'H IND.2\'/kgSAC, respectively, at AVOL of 13.5 kgDQO/\'M POT.3\'.d. Biohydrogen yield showed no tendency to change with varying influent concentration at constant cycle length neither with varying cycle length at constant influent concentrations, indicating the need to study the behavior of the process as a function of applied organic load as well as of the variables which define the applied organic load. (AU)

• FAPESP's process: 10/03876-6 - Effects of organic load on bio-hydrogen production through synthetic wastewater in an ASBR
• Grantee: Mehdi El Manssouri
• Support Opportunities: Scholarships in Brazil - Master