PMID- 30903908
OWN - NLM
STAT- MEDLINE
DCOM- 20190503
LR  - 20190503
IS  - 1879-1026 (Electronic)
IS  - 0048-9697 (Linking)
VI  - 670
DP  - 2019 Jun 20
TI  - Impact of molecular structure and charge property of chitosan based polymers on 
      flocculation conditioning of advanced anaerobically digested sludge for 
      dewaterability improvement.
PG  - 98-109
LID - S0048-9697(19)31138-6 [pii]
LID - 10.1016/j.scitotenv.2019.03.156 [doi]
AB  - Anaerobically digested sludge is generally difficult to dewater due to the 
      release of sticky soluble microbial products in anaerobic digestion. Traditional 
      flocculation processes have the disadvantages of high chemical dosing and solid 
      increase, thus affecting subsequent land application. Therefore, it is desirable 
      to develop low-cost, biodegradable, nontoxic and environmentally friendly sludge 
      conditioners. In this work, the chitosan (CTS) was chemically modified by 
      incorporating functional groups (amino group and the carboxyl group) to improve 
      its water solubility and flocculation efficiency, and the anaerobically digested 
      sludge conditioning effectiveness of different chitosan based flocculants were 
      comparatively investigated. Results indicated that aminated chitosan (CTS-DMDAAC) 
      and CTS performed well in sludge dewatering improvement in terms of specific 
      resistance to filtration (SRF) and Capillary suction time (CST), which decreased 
      to a minimum when the concentration of conditioner reached to 35 mg/g TSS. Flocs 
      conditioned by CTS-DMDAAC were more compact and aggregated more efficiently than 
      that flocculated with CTS and C-CTS (carboxylated chitosan). CTS-DMDAAC and CTS 
      interacted with extracellular polymeric substance (EPS) by charge neutralization 
      and complexation adsorption, which caused the densification of gel-like structure 
      and enhancement of floc strength of sludge. Scanning electron microscope (SEM) 
      analysis showed that after CTS-DMDAAC treatment, there were plentiful large pores 
      distributed on floc surface, which provided channels for water release under 
      pressure filtration. Confocal laser scanning microscopy (CLSM) confirmed that 
      protein-like substances were agglomerated under flocculation conditioning, which 
      was responsible for the promotion of sludge dewatering performance. This study 
      provides a green and promising solution for the improvement of anaerobically 
      digested sludge dewatering performance.
CI  - Copyright (c) 2019 Elsevier B.V. All rights reserved.
FAU - Zhang, Weijun
AU  - Zhang W
AD  - School of Environmental Studies, China University of Geosciences, Wuhan 430074, 
      Hubei, China.
FAU - Wang, Huidi
AU  - Wang H
AD  - School of Environmental Studies, China University of Geosciences, Wuhan 430074, 
      Hubei, China.
FAU - Li, Liqing
AU  - Li L
AD  - School of Environmental Studies, China University of Geosciences, Wuhan 430074, 
      Hubei, China. Electronic address: li-liqing@163.com.
FAU - Li, Dandan
AU  - Li D
AD  - School of Environmental Studies, China University of Geosciences, Wuhan 430074, 
      Hubei, China.
FAU - Wang, Qiandi
AU  - Wang Q
AD  - School of Environmental Studies, China University of Geosciences, Wuhan 430074, 
      Hubei, China.
FAU - Xu, Qiongying
AU  - Xu Q
AD  - School of Environmental Studies, China University of Geosciences, Wuhan 430074, 
      Hubei, China.
FAU - Wang, Dongsheng
AU  - Wang D
AD  - School of Environmental Studies, China University of Geosciences, Wuhan 430074, 
      Hubei, China; State Key Laboratory of Environmental Aquatic Chemistry, Research 
      Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 
      100085, China.
LA  - eng
PT  - Journal Article
DEP - 20190312
PL  - Netherlands
TA  - Sci Total Environ
JT  - The Science of the total environment
JID - 0330500
RN  - 0 (Polymers)
RN  - 0 (Sewage)
RN  - 9012-76-4 (Chitosan)
SB  - IM
MH  - Chitosan/*chemistry
MH  - Extracellular Polymeric Substance Matrix
MH  - Filtration
MH  - Flocculation
MH  - Molecular Structure
MH  - Polymers/chemistry
MH  - Sewage/*chemistry
MH  - Waste Disposal, Fluid/*methods
OTO - NOTNLM
OT  - Chitosan based polymers
OT  - Extracellular polymeric substance (EPS)
OT  - Flocculation conditioning
OT  - Sludge dewatering
EDAT- 2019/03/25 06:00
MHDA- 2019/05/06 06:00
CRDT- 2019/03/24 06:00
PHST- 2019/01/09 00:00 [received]
PHST- 2019/03/09 00:00 [revised]
PHST- 2019/03/11 00:00 [accepted]
PHST- 2019/03/25 06:00 [pubmed]
PHST- 2019/05/06 06:00 [medline]
PHST- 2019/03/24 06:00 [entrez]
AID - S0048-9697(19)31138-6 [pii]
AID - 10.1016/j.scitotenv.2019.03.156 [doi]
PST - ppublish
SO  - Sci Total Environ. 2019 Jun 20;670:98-109. doi: 10.1016/j.scitotenv.2019.03.156. 
      Epub 2019 Mar 12.