The influence of hydrolysis induced biopolymers from recycled aerobic sludge on specific methanogenic activity and sludge filterability in an anaerobic membrane bioreactor

Using polyaluminum chloride and polyacrylamide to control membrane fouling in a cross-flow anaerobic membrane bioreactor

“…As shown in Table 1, SMP concentration (r¼0.992, po0.01) and zeta potential (r¼ À0.961, po0.01) demonstrated statistically significant correlations with SRF for mixed sludge liquor with added PAC. A high level of SMP has been reported to be detrimental to sludge filterability and membrane fouling control [9,25,26]. The organic matter in SMP likely builds up a gel layer on the membrane surface, blocking the membrane pores and filling the gaps in fouling layer to generate high filtration resistance.…”

Multiple effects of trace elements on methanogenesis in a two-phase anaerobic membrane bioreactor treating starch wastewater

“…What is more, recent researches in metaproteomics and metabolomics showed that the metabolism networks of AD are related to cooperation of many pathways (Vanwonterghem et al 2014). In another aspect, chemical forms and transformation of TEs were also critical to their effects, such as bioavailable forms and metal sulphide (Ahring 2003). So, the balances of multiple effects still need to be evaluated by more studies in various indicators for different purposes according to the digestion system.…”

“…Preciously suggested approach to stimulate methanogenesis was addition of trace elements (TEs) based on mechanisms of micronutrition and relief inhibition by metal sulphur (Ahring 2003;Mao et al 2015). For example, TEs were supplied in 60 AD plants with low micronutrient levels, and digester performance was improved after supplementation (Lindorfer et al 2012).…”

“…In general, TEs stimulate AD as critical micronutrition through (1) composing metal enzyme and metal coenzyme, (2) activating enzyme and coenzyme and (3) relieving sulphur or ammonia inhibition (Ahring 2003;Mao et al 2015). According to these mechanisms, many related effects should be observed in TE addition, such as more methane production due to inhibition relieved, higher activity of methanogenic microorganisms due to enzyme catalyse, more biomass growth due to sufficient micronutrition and, thus, higher COD removal (Sambusiti et al 2014).…”

“…To evaluate the methane production activity induced by TEs, the maximum slope of accumulated methane production was taken for calculating SMA as maximum specific rate (Buntner et al 2014). It is different from another SMA as kinetics coefficient k in the first-order kinetics or the Monod model of methane productions (Strömberg et al 2015), because the SMA as maximum specific rate has more links with the performance of the AnMBR under the biogas-pH control strategy (Yu et al 2016).…”