Banca de DEFESA: HELOISA VITAL DOMINGOS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : HELOISA VITAL DOMINGOS
DATE: 26/08/2022
TIME: 09:00
LOCAL: Sala de reuniões do Conselho do CTEC
TITLE:

Methanogenic production from anaerobic codigestion of elephant grass silage with vinasse in batch reactor

KEY WORDS:

biomethane; anaerobic codigestion; elephant grass; vinasse; silage; Box-Behnken.

PAGES: 109
BIG AREA: Engenharias
AREA: Engenharia Sanitária
SUBÁREA: Tratamento de Águas de Abastecimento e Residuárias
SPECIALTY: Estudos e Caracterização de Efluentes Industriais
SUMMARY:

The use of biomass as a substrate in anaerobic digestion for energy production
purposes has been highlighted in the last three decades, considering climate
emergency and the impacts arising from non-renewable energy sources. In this
context, sugarcane vinasse and elephant grass have significant potential for biogas
production, but their application via anaerobic co-digestion has been little investigated.
Therefore, the aim of this study was to evaluate the methane yield of the co-digestion
of these substrates in batch reactors, using Box-Behnken experimental design. The
adopted factors were ensiling time of elephant grass (40, 80 and 120 days),
silage:vinasse ratio (25:75, 50:50 and 75:25), and concentration of alkaline
pretreatment of elephant grass (NaOH 0.5%, 2.25% and 4%w/v). Most reactors showed
COD and carbohydrate removal greater than 60%, indicating significant removal of
organic matter and efficiency of anaerobic digestion. Cumulative methane production
data was properly fitted to the modified Gompertz sigmoid model (R2 ≈ 0.99).
Cumulative methane yield values ranged from 190.77 to 1,729.80 mLCH4/gSV. The
highest yields were observed in the reactors which used silage:vinasse ratio equal to
25:75, ensiling time between 80 and 120 days, and pre-treatment solution of NaOH
2.25%w/v to 4.00%w/v. According to ANOVA, proportion between substrates was the
only factor with a significant effect (p < 0.05) on cumulative methane yield. The
regression model proposed to estimate the yield as a function of the adopted factors
showed a high regression coefficient (R2 = 0.93). It is expected that the results will
contribute to the optimization and implementation, on a larger scale, of bioenergy
generation projects from the anaerobic treatment of sugarcane vinasse and elephant
grass silage.

BANKING MEMBERS:
Presidente - 1774383 - EDUARDO LUCENA CAVALCANTE DE AMORIM
Interna - 2151064 - DAYANA DE GUSMAO COELHO
Externo à Instituição - ANDERSON CARLOS MARAFON - UFPel
Externa à Instituição - JULIANA SILVA MARTINS - UNICAMP