Membrane separation to improve degradation of road side grass by rumen enhanced solid incubation

Abstract

Membrane separation proved to be an excellent means to maintain high residence time of microorganisms in an anaerobic hydrolysis reactor, and relatively low concentration of hydrolysis products. The microbial biocommunity typical for the rumen environment could be maintained, and the reactor efficiency of the reactor improved. Less than 4 days were reqired to reach almost complete hydrolysis of the grass fed into the reactor. To avoid blocking of the membrane unit, a backwash system is necessary. The membranes needed to be backwashed every 20 min with 4 bar gas-pressure for 10 s. After this treatment the initial permeability was regained. The plant was operated with a flux of 12 ml h(-1) cm(-2) on average. The transmembrane pressure was in the range of 0.8-0.9 bar. 90% of the dissolved fatty acids permeated through the membrane.

Application of rumen microorganisms for enhanced anaerobic fermentation of corn stover

“…After harvesting the crops, the residue is normally left in the field. This waste might be a potential resource for the production of renewable energy through chemical or biological conversion [2][3][4][5]. For example, it could be fermented to produce volatile fatty acids (VFA) with a yield of 0.50-0.55 g acid equivalent g À1 dry ash-free corn stover by using anaerobic cultures and dilute alkali pre-treatment [1].…”

“…Recently, the potential applications of rumen microorganisms in artificial rumen reactors for the conversion of cellulose-rich wastes have been explored [4,5,10]. A twostage anaerobic process has been developed [4] in which the first stage is an artificial rumen reactor where cellulose-laden wastes are degraded to VFA and carbon dioxide by rumen microorganisms.…”

“…In this closed fluid system cellulose is almost www.elsevier.com/locate/procbio Process Biochemistry 40 (2005) 2371-2377 completely converted into biogas. Lignocellolosic wastes, such as cereal straws and domestic refuse are also able to be degraded by rumen microorganisms in a semi-continuous system [5,11].…”

Enhanced biogas yield from energy crops with rumen anaerobic fungi

“…Many authors up to now have applied enzymes and/or living cultures of aerobic cellulolytic fungi . Furthermore, experiments with rumen organisms were also performed . Improvement of biomass hydrolysis by bioaugmentation using rumen fungi ( Neocallimastigomycota ) during anaerobic digestion could be an interesting way to enhance decomposition of lignocellulosic material and consequently improve biogas production.…”

Animal digestive strategies versus anaerobic digestion bioprocesses for biogas production from lignocellulosic biomass

“…Numerous bioreactors were designed to degrade the lignocellulosic biomass with rumen microbial consortium. The processes developed in this field range from the very simple apparatus such as a batch reactor (Cerrato-Sanchez et al 2007;Hu et al 2004Hu et al , 2007Raizada et al 2003;Seon et al 2003) to a complicated apparatus designed to work on the continuous mode and even equipped with semipermeable membranes to remove the VFAs produced (Czerkawski and Cheng 1988;Dalhoff et al 2003;Gijzen et al 1988;Nair et al 2005). These anaerobic digestion processes were related to both animal physiology and environmental bioengineering in order to respectively improve the nutrition of livestock as in the rumen simulation technique (RUSI-TEC) and to improve the production of biogas from lignocellulosic wastes as in the rumen derived anaerobic digestion system (RUDAD).…”