Additional Paper Waste in Pulping Sludge for Biohydrogen Production by Heat-Shocked Sludge

Abstract

Dark anaerobic fermentation is an interesting alternative method for producing biohydrogen (H(2)) as a renewable fuel because of its low cost and various usable organic substrates. Pulping sludge from wastewater treatment containing plentiful cellulosic substrate could be feasibly utilized for H(2) production by dark fermentation. The objective of this study was to investigate the optimal proportion of pulping sludge to paper waste, the optimal initial pH, and the optimal ratio of carbon and nitrogen (C/N) for H(2) production by anaerobic seed sludge pretreated with heat. The pulping sludge was pretreated with NaOH solution at high temperature and further hydrolyzed with crude cellulase. Pretreatment of the pulping sludge with 3% NaOH solution under autoclave at 121 °C for 2 h, hydrolysis with 5 FPU crude cellulase at 50 °C, and pH 4.8 for 24 h provided the highest reducing sugar production yield (229.68 ± 2.09 mg/g(TVS)). An initial pH of 6 and a C/N ratio of 40 were optimal conditions for H(2) production. Moreover, the supplement of paper waste in the pulping sludge enhanced the cumulative H(2) production yield. The continuous hydrogen production was further conducted in a glass reactor with nylon pieces as supporting media and the maximum hydrogen production yield was 151.70 ml/g(TVS).

Fermentative Hydrogen Production Using Disintegrated Waste-Activated Sludge by Low-Frequency Ultrasound Pretreatment

“…Wan et al observed acetate-type fermentation when the hydrolysate of waste-activated sludge was used as the substrate . Chairattanamanokorn et al obtained the acetate-type fermentation when the C/N ratio was adjusted to 40 . In our previous study, the change of fermentation type from butyrate to acetate was observed when glucose was added to γ-irradiation-treated sludge .…”

“…55 Chairattanamanokorn et al obtained the acetatetype fermentation when the C/N ratio was adjusted to 40. 56 In our previous study, the change of fermentation type from butyrate to acetate was observed when glucose was added to γirradiation-treated sludge. 35 Thus, it can be seen that acetatetype fermentation was more likely to happen when polysaccharides were used as the main carbon source for hydrogen production.…”

A review of the potential of pretreated solids to improve gas biofuels production in the context of an OFMSW biorefinery

“…So, the organosolv pretreatment is an emergent area worth exploring because lower amounts of inhibitory compounds are generated than with dilute acid pretreatment . However, ethanol is an inhibitor for the hydrolytic process, so it is necessary to remove the traces of alcohol . One of the advantages of organosolv is the relatively easy recovery of the organic solvents by distillation and their recycling in the process.…”

“…The process has been proven at full scale; the investment cost is one of the lowest among pretreatments . It is applicable to a great variety of substrates (corn stover, pulp and paper sludge, food wastes and high sugar yields) or relatively high gas biofuels yields can be obtained (Table ). However, in some work the presence of phenolic compounds such as coniferylaldheyde has been observed; for instance, after the pretreatment of Norway spruce by Larsson et al 0.2 mmol L −1 of this compound was found after the treatment of biomass by NaOH.…”

Surfactant‐supplemented mixed bacterial cultures to produce hydrogen from paperboard mill wastewater

“…Fortunately, paperboard mill wastewater (PMW) can be considered as a potential source for generation of renewable bioenergies in the form of methane and/or hydrogen via anaerobic digestion process . However, PMW mainly comprises complex compounds such as cellulose, hemicellulose, and lignin, which are recalcitrant to microbial and enzymatic action . Moreover, spillage of biocides, oil, dyes, acids, etc., in the PMW will certainly reduce the activity of consortium anaerobic bacteria .…”