Permanganate/bisulfite (PM/BS) conditioning–horizontal electro-dewatering (HED) of activated sludge: Effect of reactive Mn(III) species

Guo, Xinxin; Wang, Yili; Wang, Dongsheng

doi:10.1016/j.watres.2017.08.027

Cited by 79 publications

(9 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…After treatment, the Zeta potential of the sludge increases, indicating that F/T and AC can enhance the electrophoretic mobility of the sludge during EP, and the increased electrophoretic mobility will weaken the polarity between the substances in the sludge, resulting in the reduction of hydrophilicity, thereby enhancing the dehydration performance, which is consistent with the study of Cao et al in electro-osmotic dehydration of sludge (Cao et al 2019). Moreover, according to the DLVO theory, the negative increase of the Zeta potential in the sludge solution can enhance the electrostatic repulsion between the ocs and prevent the sludge from forming tighter ocs and di cult dewatering (Guo et al 2017).…”

Section: Changes In Zeta Potentialsupporting

confidence: 85%

Freeze–thaw combined with activated carbon improves electrochemical dewaterability of sludge: Analysis of sludge floc structure and dewatering mechanism

Huang

Song

Yin

et al. 2021

Preprint

View full text Add to dashboard Cite

Freeze–thaw (F/T) and electrochemistry are environment-friendly and efficient sludge treatment technologies. In this study, F/T and electrochemistry were combined in the pretreatment of sludge dewatering in the laboratory, and activated carbon (AC) was added to improve the electrochemical dewatering performance of sludge. During the experiment, the effect of F/T on the floc structure was analyzed by a laser particle analyzer and scanning electron microscope. F/T treatment not only improved the dewatering performance of sludge, but also promoted the aggregation of sludge flocs into larger particles. The median diameter (D50) increased from 45.27 µm to 128.94 µm. Then, the intracellular polymer of large-particle sludge was analyzed by three-dimensional excitation–emission matrix (3D-EEM). The tightly bound extracellular polymeric substances (TB-EPS) still contained a large amount of protein substances, which hindered the improvement of sludge dewatering performance. AC was added to the thawed sludge solution before electrochemical treatment (EP). The conductivity of AC enhanced the effect of EP, thereby cracking the sludge flocs. Thus, the light intensity of TB-EPS in the 3D-EEM fluorescence spectroscopy was decreased, and the D50 was also reduced to 105.3 µm. The final specific resistance of filtration and water content were reduced by 96.39% and 32.17%, respectively. Element analysis of the sludge cake after dehydration showed that the addition of AC significantly improved the combustion efficiency of the sludge cake. Moreover, preliminary economic analysis showed that the cost of this research was low, which indicated the potential application value of combined treatment.

show abstract

Section: Changes In Zeta Potentialsupporting

confidence: 85%

Freeze–thaw combined with activated carbon improves electrochemical dewaterability of sludge: Analysis of sludge floc structure and dewatering mechanism

Huang

Song

Yin

et al. 2021

Preprint

View full text Add to dashboard Cite

show abstract

“…Many studies have demonstrated that sludge filtration properties mainly depend on properties of the LB‐EPS fraction. High concentrations of protein‐like substances and polysaccharide materials in LB‐EPS may negatively impact sludge dewaterability . Our results showed that the organic compounds in LB‐EPS were more strongly correlated to sludge dewaterability than the corresponding compounds in S‐EPS and TB‐EPS.…”

Section: Resultsmentioning

confidence: 67%

“…High concentrations of protein-like substances and polysaccharide materials in LB-EPS may negatively impact sludge dewaterability. 10,12,36 Our results showed that the organic compounds in LB-EPS were more strongly correlated to sludge dewaterability than the corresponding compounds in S-EPS and TB-EPS. To learn more about the changes in key functional groups, LB-EPS samples were characterized using a FTIR spectrometer and XPS spectra.…”

Section: Effect On Key Functional Groups In Lb-epsmentioning

confidence: 68%

Comprehensive insights into the inorganic coagulants on sludge dewatering: comparing aluminium and iron salts

Liang

Zhang

Huang

et al. 2019

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

BACKGROUND Extracellular polymeric substances (EPS) play an important role in sludge dewatering. Inorganic coagulants treatment has been widely used to remove the EPS and improve sludge dewaterability. This research evaluates whether there are advantages of selecting one of two chemical coagulation pretreatments, conventional aluminium or iron salts, over the other to enhance sludge dewaterability. The study traced variations in EPS characteristics to understand the mechanisms of sludge dewaterability. RESULTS The results showed that iron coagulants improved dewatering more than aluminium coagulants, by approximately 28.66%. The improved sludge dewaterability was further confirmed in pilot‐scale experiments. Compared with aluminium salts conditioning, iron salts were better able to neutralize stronger charge, formed smaller and more compact flocs, and had a stronger acidification effect. Sludge dewaterability was significantly related to EPS concentrations (i.e. the protein and polysaccharides), EPS composition (i.e. tyrosine/tryptophan amino acid, tyrosine/tryptophan protein, and polysaccharide), and functional groups (i.e. random coil, β‐sheet, and Npr) in the loosely bound EPS (LB‐EPS). A two‐step mechanism was proposed for the iron conditioning process. Moreover, the economic analysis shows iron treatment was more economical than that of aluminium. CONCLUSION Iron salts conditioning removed more LB‐EPS than aluminium salts, thus more significantly improving sludge dewaterability. © 2018 Society of Chemical Industry

show abstract

“…However, most of them are not treated and disposed properly . Dewatering plays a significant role in the transportation and disposal of the WAS, which is closely related to the cost of the subsequent treatment . Raw WAS has difficulties to dewater due to its colloidal and porous fractal network structure, making it a challengeable issue.…”

Section: Introductionmentioning

confidence: 99%

Altering Extracellular Biopolymers and Water Distribution of Waste Activated Sludge by Fe(II) Persulfate Oxidation with Natural Zeolite and Polyelectrolyte as Skeleton Builders for Positive Feedbacks to Dewaterability

Wang

Tan

Pan

et al. 2019

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

Ferrous persulfate (Fe(II)/S2O8 2–) oxidation has gained much attention due to its outstanding oxidizability and high efficiency in upgrading waste activated sludge (WAS) dewaterability. Even though the Fe(II)/S2O8 2– technique possesses a myriad of advantages, its potential could be further magnified for future upscaling and real-world application especially when coupled with other alternative chemicals. In this study, the potential benefits of Fe(II)/S2O8 2– oxidation coupled with natural zeolite and poly(dimethyl diallyl ammonium chloride) (PDADMAC) for enhancing WAS dewaterability were investigated. The vacuum filtration test was used to evaluate the dewatering effectiveness. Variations in different extracellular polymeric substance (EPS) fractions, water distribution, functional groups, and microstructures were identified to elucidate the underlying dewatering principles and kinetics. The results demonstrated that the combination of Fe(II)/S2O8 2– with zeolite and PDADMAC had a significant effect on enhancing WAS dewaterability. The optimal conditions obtained were 2.25/1.8 mmol-Fe(II)/S2O8 2–/g-VS, 0.5 g-zeolites/g-VS, and 0.3 g-PDADMAC/g-VS with up to 117 g-H2O/g-VS removal (moisture content: 64.5%). Further analysis revealed the three-step dewatering mechanisms: (i) the SO4·– generated by Fe(II)/S2O8 2– oxidation attacked the WAS flocs and cells, broke the bonds of O–H, C–C, and OCNH– in high-molecular-weight biopolymers, and decomposed them into micromolecule organics and even inorganics, thus liberating EPS- and cell-bound water, (ii) the broken WAS flocs were then reflocculated via adsorption bridging and charge neutralization induced by PDADMAC, and (iii) during the subsequent filtration, zeolites created channels/cavities for water release by forming a multiple void skeletal lattice while alleviating the clogging of filtration cloth. In addition, the cost-benefit analysis revealed that the combined Fe(II)/S2O8 2–/zeolites/PDADMAC process represented much greater attractiveness in saving cost and real implementations than the zerovalent iron/persulfate and classical Fenton process.

show abstract

Permanganate/bisulfite (PM/BS) conditioning–horizontal electro-dewatering (HED) of activated sludge: Effect of reactive Mn(III) species

Cited by 79 publications

References 53 publications

Freeze–thaw combined with activated carbon improves electrochemical dewaterability of sludge: Analysis of sludge floc structure and dewatering mechanism

Freeze–thaw combined with activated carbon improves electrochemical dewaterability of sludge: Analysis of sludge floc structure and dewatering mechanism

Comprehensive insights into the inorganic coagulants on sludge dewatering: comparing aluminium and iron salts

Altering Extracellular Biopolymers and Water Distribution of Waste Activated Sludge by Fe(II) Persulfate Oxidation with Natural Zeolite and Polyelectrolyte as Skeleton Builders for Positive Feedbacks to Dewaterability

Contact Info

Product

Resources

About