Effects of newly prepared alkaline ferrate on sludge disintegration and methane production: Reaction mechanism and model simulation

He, Haiyang; Liu, Yulei; Wang, Xianshi; Huang, Zhuangsong; Xu, Chengbiao; Yang, Tao; Zhang, ZhongXiang; Wang, Lu

doi:10.1016/j.cej.2018.03.031

Cited by 45 publications

(9 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Chen et al proved that the methane production of thermal-alkaline pretreated WAS (pH of 12 at 134 ± 1 °C for 30 min) and the thermal pretreated WAS (134 ± 1 °C for 30 min) was 2.20 and 1.88 times that of the raw WAS, respectively . He et al demonstrated that the maximum methane accumulation from WAS was attained at 116 mL/g VS after 200 mg Fe (VI)/L of alkaline ferrate pretreatment, resulting in a 42.5% increase …”

Section: Introductionmentioning

confidence: 99%

Enhancing Methane Production from Anaerobic Digestion of Waste Activated Sludge through a Novel Sodium Percarbonate (SPC) Pretreatment: Reaction Kinetics and Mechanisms

et al. 2022

View full text Add to dashboard Cite

Sodium percarbonate (SPC), a harmless and economical inorganic peroxide, has recently attracted increasing attention in pollutant degradation and sludge treatment. However, the feasibility and mechanisms of SPC pretreatment on improving the anaerobic digestion of waste activated sludge (WAS) have never been revealed before. Therefore, this study is aimed to fill this research gap. The results showed that with the SPC dosage increasing from 0 to 0.3 g/g total suspended solids, the maximum methane production was enhanced by 37.2%. Model-based analysis indicated that SPC pretreatment concurrently enhanced the hydrolysis rate and biochemical methane potential of WAS. Mechanistic studies were performed from two stages, i.e., sludge disintegration and anaerobic digestion. SPC pretreatment accelerated sludge solubilization through disintegrating extracellular polymeric substances and cell walls of WAS, which provided substantial substrates for subsequent anaerobic digestion. Meanwhile, the active radicals contributing to pretreatment were proven to be OH, •O2 –, and CO3 •–. The strong oxidizing radicals promoted the conversion of organics from nonbiodegradable to biodegradable substances, thus improving the biodegradability of WAS. Furthermore, SPC pretreatment improved hydrolysis, acidogenesis, and methanogenesis bioprocesses of WAS and enriched key microbes involved in complex organic decomposition (e.g., Exiguobacterium sp.), metabolic intermediate generation (e.g., Clostridioides sp.), and methane conversion (Methanosaeta sp. and Candidatus_Methanofastidiosum sp.).

show abstract

Section: Introductionmentioning

confidence: 99%

Enhancing Methane Production from Anaerobic Digestion of Waste Activated Sludge through a Novel Sodium Percarbonate (SPC) Pretreatment: Reaction Kinetics and Mechanisms

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Disposing these emerging pollutants and investigating the reaction mechanism have become a core issue in environmental related investigations. Ferrate (K 2 FeO 4 ) is a powerful oxidant and can efficiently eliminate organics with electron rich moieties such as phenols, olefins, anilines, and amines. − As a disinfection agent, ferrate would inactive microbes, pathogens, − and control the formation of many kinds of halogenated disinfection byproducts (DBPs). , Besides, the nanosized ferric particles formed in ferrate reduction process have great ability for adsorbing hazardous ions − and facilitating source water coagulation. − These properties make ferrate a promising agent in environmental remediation and water treatment. − …”

Section: Introductionmentioning

confidence: 99%

Impact of Phosphate on Ferrate Oxidation of Organic Compounds: An Underestimated Oxidant

Huang

Wang

Liu

et al. 2018

Environ. Sci. Technol.

Self Cite

126

View full text Add to dashboard Cite

Ferrate (K2FeO4) is a powerful oxidant and up to 3 mol of electrons could be captured by 1 mol of ferrate in the theoretical conversion of Fe(VI)–Fe(V)–Fe(IV)–Fe(III). However, it is reported that the utilization efficiency of the ferrate oxidation capacity is quite low because of the rapid autodecomposition of intermediate iron species, which negatively influences the potential of ferrate on organic pollutants control. We accidentally found that for the ferrate oxidation of carbamazepine (CBZ), bisphenol S (BPS), diclofenac (DCF), and ciprofloxacin (CIP), the determined reaction rate constants were 1.7–2.4 times lower in phosphate buffer than those in borate buffer at pH 8.0. For the reaction of ferrate with 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) at pH 7.0, the determined reaction stoichiometries were 1:1.04 in 100 mM phosphate buffer, 1:1.18 in 10 mM phosphate buffer, and 1:1.93 in 10 mM borate buffer, respectively. The oxidation ability of ferrate seems depressed in phosphate buffer. A kinetic model involving the oxidation of ABTS by Fe(VI), Fe(V) and Fe(IV) species was developed and fitted the ABTS•+ formation kinetics well under different buffer conditions. The results showed that phosphate exhibited little influence on the oxidation ability of Fe(VI) and Fe(IV) species, but decreased the specific rate constants of ABTS with Fe(V) species by 1–2 orders of magnitude, resulting in the outcompeting of Fe(V) autodecomposition pathway. The complexation between phosphate anions and Fe(V) species may account for the inhibition effect of phosphate buffer. Considering that many studies regarding ferrate oxidation were carried out in phosphate buffer, the actual oxidation ability of ferrate may be underestimated.

show abstract

“…On the basis of the support of PF, it was experimentally demonstrated that sludge dewaterability and production of SCFA and methane were enhanced. − Moreover, the end product (i.e., Fe(OH) 3 ) after PF reaction will remain in the sludge in solid form. It could be an excellent flocculant and adsorbent; it could not only decrease the sludge volume but also reduce the heavy metals and evil odor in sludge. , In addition to the above benefits, it was further found in this study that both the hydrogen accumulation from WAS dark fermentation and substrate transformations from nonbiodegradable to biodegradable were enhanced when the PF was applied, during which the reduction of final disposed WAS and the recovery of a green energy gas (i.e., hydrogen) were achieved. According to the results obtained in this work and reported in the previous studies, it therefore could be speculated that the addition of PF could not only remove the toxic and hazardous substances but also recover some energy or resources (such as hydrogen and SCFA) from WAS.…”

Section: Resultsmentioning

confidence: 99%

“…Potassium ferrate (K 2 FeO 4 , PF), which has higher reactivity and selectivity than traditional oxidants, and has excellent disinfecting and coagulating ability, is considered a strong oxidant. , Moreover, when PF is dissolved in a hydrous medium, it eventually forms Fe(OH) 3 and O 2 after a series of reactions, and the Fe(OH) 3 could be an excellent adsorbent of pollutants. , Due to these characters, PF, which is considered a multifunctional green oxidant, has been intensively applied in soil remediation, aquaculture, sewage treatment, groundwater remediation, and many other fields. , In recent years, the application of PF has expanded into a new field, i.e., sludge treatment. Previous studies have demonstrated that sludge dewaterability, recovery of resources and energy, i.e., SCFA and CH 4 , and the removal of toxic and hazardous substances such as heavy metal, nonylphenol, and hormones are effectively promoted when sludge is pretreated with PF. − For example, Wu et al found that 500 mg/L of PF reduced sludge with a specific resistance to filtration (SRF) from 18.6 × 10 12 to 2.7 × 10 12 m/kg and achieved a 69% sludge disintegration degree . Diak and Ormeci reported the concentrations of hormones including estriol, 17α-ethinylestradiol, 17α-estradiol, mestranol, equilin, and equilenin decreased significantly when the anaerobically digested sludge was treated by 1 g/L PF.…”

Section: Introductionmentioning

confidence: 99%

Performance and Mechanism of Potassium Ferrate(VI) Enhancing Dark Fermentative Hydrogen Accumulation from Waste Activated Sludge

Kuang

Zhang

et al. 2020

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

Potassium ferrate (K2FeO4, PF), as a multifunctional green oxidant, has been used for oxidative degradation of pollutants and recovery of resources in sludge. However, its impact on the generation of hydrogen in anaerobic fermentation of waste activated sludge (WAS) is still unclear. The purpose of this work is to study the influence of PF on the dark fermentative hydrogen production. Experimental result suggested that as PF increased from 0 to 0.09 g/g of TSS (total suspended solids), the maximal hydrogen production increased from 1.47 to 8.35 mL/g VSS (volatile suspended solids). A further increase to 0.12 g/g of TSS resulted in a decrease in hydrogen yield. Mechanism studies revealed that that the addition of PF not only facilitated the disruption of sludge cell and extracellular polymeric substances (EPS) but also increased the proportion of biodegradable organics, providing more bioavailable organics for subsequent reactions involved in hydrogen accumulation. Although the activities of microorganisms relevant to dark fermentation were suppressed to a certain extent in the presence of PF, the induced suppression to hydrogen consumers was more severe. Microbial studies indicated that the relative abundances of hydrogen producers (such as Petrimonas and Proteiniborus) were augmented while hydrogen consumers (such as Methanosaeta and Methylocaldum) decreased in the presence of PF.

show abstract

Effects of newly prepared alkaline ferrate on sludge disintegration and methane production: Reaction mechanism and model simulation

Cited by 45 publications

References 43 publications

Enhancing Methane Production from Anaerobic Digestion of Waste Activated Sludge through a Novel Sodium Percarbonate (SPC) Pretreatment: Reaction Kinetics and Mechanisms

Enhancing Methane Production from Anaerobic Digestion of Waste Activated Sludge through a Novel Sodium Percarbonate (SPC) Pretreatment: Reaction Kinetics and Mechanisms

Impact of Phosphate on Ferrate Oxidation of Organic Compounds: An Underestimated Oxidant

Performance and Mechanism of Potassium Ferrate(VI) Enhancing Dark Fermentative Hydrogen Accumulation from Waste Activated Sludge

Contact Info

Product

Resources

About