The bioactivation procedure for increasing the sulphate-reducing bacteria in a UASB reactor

Abstract

-Bioactivation, a procedure to obtain anaerobic sulphidogenic sludge, was developed in order to increase sulphate reduction and, consequently, sulphide production to remove metals from effluents. This procedure, in which the source of carbon/energy (lactate) is gradually replaced, consisted of three operational conditions. It was observed that bioactivation took six months so there was a 100-fold increase in the population of sulphate-reducing bacteria estimated by the most-probable-number (MPN) when molasses was employed as a new source.

Determination of the elemental composition of molasses and its suitability as carbon source for growth of sulphate-reducing bacteria

“…A satisfactory level of sulphate reduction by SRB using molasses as electron donor has been reported previously [45]. Our study showed that molasses at concentrations of 1, 2.5 and 5 g/l supported the growth of our SRB culture.…”

Microbial conversion of sulfur dioxide in flue gas to sulfide using bulk drug industry wastewater as an organic source by mixed cultures of sulfate reducing bacteria

“…The SEM micrographs shown in Fig. 6 clearly depicted the formation of SRB biofilm on the surface of GAC particles throughout the AFBR [37]. Further, characteristic rod shaped morphology of the microorganism was distinctly apparent on the surface of the GAC particles.…”

“…It was also noted from the literature that, in general, granular biomass or biofilm presented higher threshold toxicity [32,33]. Sulfide toxicity was reported at lower concentrations in suspended-growth systems than in anaerobic filters, confirming that biofilm or granular/flocculent sludge presented a much more complex system than completely mixed reactors in the context of sulfide toxicity [31][32][33][34][35][36][37]. Therefore, the results obtained in the present studies with respect to the free and dissolved sulfide were in support of previous studies.…”

A review on upflow anaerobic sludge blanket reactor: Factors affecting performance, modification of configuration and its derivatives

“…The affinity for hydrogen for SRB is higher than that for methane‐producing archaea (MPA). From the previous works, it is clear that sulfate removal and predominance of bacterial species depend on COD/SO 4 2− ratio (increase in COD/SO 4 2− ratio is meant to increase sulfate removal) (Goncalves et al, 2005; Wang et al, 2012). Co‐digestion can be adopted for the treatment of low‐strength wastewater and sulfate‐containing wastewater to improve the COD/SO 4 2− ratio that can enhance sulfate removal in addition to increasing the biogas production.…”