Influence of linear alkylbenzene sulfonate and ethanol on the degradation kinetics of domestic sewage in co-digestion with commercial laundry wastewater

Author(s)

Macedo, Thais Zaninetti ^[1] ; Silva, Edson Luiz ^[2] ; Sakamoto, Isabel Kimiko ^[1] ; Zaiat, Marcelo ^[1] ; Varesche, Maria Bernadete A. ^[1]

Affiliation

^[1] Univ Sao Paulo, Engn Sch Sao Carlos, EESC, Dept Hydraul & Sanitat, Lab Biol Proc, Campus 2, BR-13563120 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Chem Engn, Rod Washington Luiz, Km 235, SP 310, BR-13565905 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Bioprocess and Biosystems Engineering; v. 42, n. 9, p. 1547-1558, SEP 2019.
• Web of Science Citations: 0

Abstract

The influence of ethanol on the degradation kinetics of linear alkyl benzene sulfonate (LAS) and organic matter was investigated using batch experiments with different initial LAS concentrations (8.3 mg L-1 to 66.9 mg L-1) and biomass immobilized on sand. Data were fitted with a substrate inhibition model. Concentrations of 2.4 mg LAS L-1 and 18.9 mg LAS L-1 (without and with ethanol) provided the maximum LAS utilization rate by the biomass (S-bm). For LAS degradation, ethanol addition favored a lower decrease in the specific substrate utilization rate (r(obs)), even at the LAS concentration usually reported as inhibitory (> 14.4 mg L-1). For organic matter degradation, r(obs) was higher with ethanol. Higher biomass differentiation was observed at higher LAS concentrations. With ethanol, microbial selection occurred at LAS concentrations near S-bm. At higher LAS concentrations, the dominance and diversity values did not change significantly with ethanol, whereas without ethanol, their behaviors were irregular. (AU)

• FAPESP's process: 15/02640-2 - Scale-up of fluidized bed reactor for treatment of commercial laundry wastewater plus domestic sewage: optimization of operational conditions
• Grantee: Thaís Zaninetti Macedo Carmelo
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 15/06246-7 - Biorefinery concept applied to biological wastewater treatment plants: environmental pollution control coupled with material and energy recovery
• Grantee: Marcelo Zaiat
• Support Opportunities: Research Projects - Thematic Grants