Quali/quantitative characterization of biogas produced in batch digesters supplied with six distinct substrates

Abstract

The present research was carried out at the DER/FCAV, São Paulo State University -Brazil, with the purpose of analyzing the quantity and quality of biogas produced by six types of substrates. The substrates used in the anaerobic digestion were characterized as: 1-Litter of broiler (LB); 2-Grinded broiler litter (GBL); 3-Broiler litter with wood shavings (BLWS); 4-Grinded broiler litter with wood shavings (GBLWS); 5-Broiler litter with peanut hulls (BLPH); 6-Grinded broiler litter with peanut hull (GBLPH). It was concluded from the collected data that: the (GBL) substrate showed a superior biogas accumulated production in relation to the other substrates, while the BLWS presented an inferior accumulated production; the grinded substrates showed higher quantities of accumulated biogas in relation to the non-grinded substrates, except for GBLPH, with 20.9 m 3 inferior than BLPH; the period of maximum biogas production started from 45 to 60 days, declining after 120 days; at 57 days after filling up the digesters the biogas produced had levels of CH 4 superior than 53%, and from 99 days all of them produced biogas with levels of CH 4 superior than 70%; LB and GBL presented higher concentrations of CH 4 in the biogas.KEYWORDS: biogas, anaerobic, organic residue, digesters. CARACTERIZAÇÃO QUALI/QUANTITATIVA DO BIOGÁS PRODUZIDO EM BIODIGESTORES DE BATELADA ALIMENTADOS COM SEIS SUBSTRATOS DISTINTOSRESUMO: Com a finalidade de se analisar quali/quantitativamente o biogás produzido por 6 tipos de substratos, efetuou-se a presente pesquisa no DER/FCAV/UNESP-SP, Brasil. Os substratos utilizados na digestão anaeróbia foram caracterizados como: 1-Esterco de aves de postura (EAP); 2-Esterco de aves de postura triturado (EAPT); 3-Esterco de aves de corte com cama de maravalha (EACM); 4-Esterco de aves de corte com cama de maravalha triturado (EACMT); 5-Esterco de aves de corte com cama de casca de amendoim (EACA), e 6-Esterco de aves de corte com cama de casca de amendoim triturado (EACAT). Dos resultados obtidos, concluiu-se que, em relação à produção acumulada de biogás, o substrato EAPT foi superior aos demais, enquanto EACM apresentou produção acumulada inferior. Em geral, os substratos triturados apresentaram maior quantidade de biogás acumulado em relação aos não triturados, exceto o EACAT, com 20,9 m³ inferior ao EACA. O período de produção máxima de biogás teve início entre 45 e 60 dias, começando a decair a partir dos 120 dias. Aos 57 dias após o enchimento dos biodigestores, o gás produzido possuía teores de CH 4 superiores a 53%, e a partir dos 99 dias, todos produziram biogás com teores de CH 4 superiores a 70%. Os substratos EAP e EAPT apresentaram maiores concentrações de metano no biogás.

Study of the biogas potential generated from residue: peanut shells

“…Crushing is an extremely important step in biodigestion. Galbiatti et al (2011) point out that the difference between the use of whole residues and crushed ones can reach an increase of 53% of the methane gas present in the biogas produced using peanut shells and poultry litter.…”

“…After 45 days of feeding, considering that the minimum period of biogas production is between 45 and 60 days (Galbiatti et al, 2011), three filters were installed, with the objective of removing hydrogen sulphide, carbon dioxide, and the humidity present in the gas, as illustrated in Figure 3. In the first filter, a steel wool roll was added, with the purpose of removing sulfate compounds, such as hydrogen sulfide, which impairs the storage of the gas and its burning (Brancoli, 2014).…”

Process Modeling and Optimization of Anaerobic Co-Digestion of Peanut Hulls and Swine Manure Using Response Surface Methodology

“…The physical methods mainly rely on grinding and milling to destroy the crystal structure of lignocellulose . Chemical pretreatment employs acid and alkalis to dissolve lignocellulosic materials, as well as break down ester bonds between lignin units. ,− Compared to monodigestion of peanut hulls, co-digestion of peanut hulls and manure has many advantages, such as increases in biogas production, balancing of the whole system, and ease of dealing with mixing wastes. ,, In this experiment, peanut hulls and swine manure were used as a mixture in AD, and the results in Table indicated that co-digestion of these two materials significantly enhanced the digestion performance. Swine manure has attracted considerable attention as a co-digestion material with raw lignocellulosic materials (e.g., peanut hulls) because it has a good buffering capacity and contains a mass of bacteria and nutrients.…”