Anaerobic treatment of rapeseed meal

Abstract

Rapeseed meal is a solid by-product obtained from rapeseed after oil extraction. This contribution summarises experiences from batch experiments as well as the long-term processing of this substrate in a laboratory stirred anaerobic reactor (continuous stirred-tank reactor). On the basis of the batch tests of hydrolysis, acidogenesis, and methanogenic activity, it was concluded that the anaerobic degradation of rapeseed meal can be performed using a one-step system and it is not necessary to include a hydrolytic-acidogenic step prior to the methanogenic step. Although the methanogenic potential of rapeseed meal appears to be very promising, the long-term processing as a single substrate led to serious problems arising from the inhibitory effects. It was, therefore, co-fermented with crude glycerol from biodiesel production. From the long-term operation of the laboratory model, it may be stated that, due to the co-fermentation of by-products from biodiesel production, the individual inhibition effects can be suppressed to a large extent and biogas production can be stabilised. The maximum organic loading rate in the continuous stirred reactor achieved 2.42 kg m −3 d −1 of volatile solids (15 g of rapeseed meal and 20 mL of gas-phase), which was 3.13 kg m −3 d −1 of chemical oxygen demand.

Tratamento do efluente do biodiesel utilizando a eletrocoagulação/flotação: investigação dos parâmetros operacionais

“…2 A demanda atual de biodiesel é atendida pelo processo convencional de transesterificação com catalisador alcalino. Portanto, diante da crescente expansão da produção de biodiesel em plantas industriais que utilizam o processo convencional, verifica-se a necessidade de tratar o efluente gerado durante este processo produtivo, 8 10 dependendo do método de lavagem aplicado até 300 L de efluente podem ser gerados para cada 100 L de biodiesel produzidos. De Boni et al 11 verificaram que são necessários no mínimo 3 L de água para cada litro de biodiesel produzido, Granjeiro 12 também utilizou 3 L de água deionizada para lavagem de 1 L de biodiesel.…”

Anaerobic Digestion of Steam-Exploded Wheat Straw and Co-Digestion Strategies for Enhanced Biogas Production

“…DDGS and RM had a higher biomethane potential compared to WS and SE, while no inhibition phenomena occurred as a result of their high nitrogen content. However, it is expected that in long-term digestion of DDGS and RM without a prior balancing of the C/N ratio, the AD system would not be biologically sustainable due to ammonium accumulation [21]. In the present study, the highest produced gas yields for DDGS and RM were 445 and 405 mL CH 4 /g VS, respectively, both at an I/S ratio of 1.75 (w/w) (Figure 2A,B).…”

“…On the other hand, RM is the main by-product of the rapeseed (Brassica napus) oil production process. The main use of these two food processing by-products (FBPs) is as livestock feed, while they also hold potential as raw materials for the production of high added-value compounds, such as biopolymers, platform chemicals and biofuels [20,21]. The expected increase in the production of biofuels due to the EU regulations [22] could potentially result in the subsequent increase in RM and DDGS production.…”

“…The use of DDGS or RM in AD could provide a market value for their producers through their efficient reuse for energy production. In the past, RM and DDGS have been tested as sole substrates in different AD systems [21,[23][24][25][26]. However, up to now, neither DDGS nor RM have been tested as co-substrates with WS in AD systems.…”

Modelling of Biogas Production from Glycerol by Anaerobic Process in a Baffled Multi-Stage Digestor

“…A major drawback of this application is the rapid accumulation of carboxylic acids leading to strong inhibition of the methanogenesis and shift to production of gas with very low methane content (8,9). Compared to the traditional complex substrates for biomethanation (manure, municipal solid waste, activated sludge, etc.)…”