Sludge conditioning, thickening and dewatering optimization in a screw centrifuge decanter: Which means for which result?

10.2166/wst.1983.0005 ◽

1983 ◽

Vol 15 (1) ◽

pp. 37-48 ◽

Cited By ~ 3

Author(s):

G E Eden

Keyword(s):

Relative Efficiency ◽

Sludge Management ◽

Chemical Methods ◽

Laboratory Techniques ◽

The origins and characteristics of sludges are described in relation to the need to dewater them for ultimate disposal. Various methods for conditioning sludge to facilitate subsequent dewatering are discussed, including physical, thermal and chemical methods. The special features of conditioning by polyelectrolytes are described and an account is given of laboratory techniques for comparing the relative efficiency of conditioners.

Changes of some sewage sludge parameters prepared with an ultrasonic field

10.2166/wst.1997.0399 ◽

1997 ◽

Vol 36 (11) ◽

pp. 101-106 ◽

Cited By ~ 15

Author(s):

January Bien ◽

Lidia Wolny

Keyword(s):

Sewage Sludge ◽

Microscopic Analysis ◽

Chemical Compounds ◽

Ultrasonic Field ◽

Water Removal ◽

Vacuum Filter ◽

Additional Criterion ◽

New Methods ◽

Studies of sewage sludge conditioning by ultrasonic field concentrate on determination of the increase of water removal effect, which depends on kind of sludge and chemical compounds used in the dewatering process. An attempt was made to find new methods of sludge preparation before dewatering. Tests presented here focused on digested and difficult dewatered sludge. The sludge was dewatered on a vacuum filter after conditioning with polyelectrolytes and the ultrasonic field. The microscopic analysis was an additional criterion to evaluate changes in the sludge structure after preparation. The polyelectrolyte dose of 3 mg/g d.m. sonicated within 15 sec. resulted in the 50% decrease of sludge volume. Results presented confirmed our previous experiences, concerning the relation between conglomerates of sludge and the effect of dewatering.

Study of sludge conditioning using organic acids chelated ferrous ion catalyzed NaClO oxidation: Evolution of extracellular polymeric substances and floc structure

Journal of Environmental Management ◽

10.1016/j.jenvman.2020.111757 ◽

2021 ◽

Vol 280 ◽

pp. 111757

Author(s):

Peng Yang ◽

Dandan Li ◽

Weijun Zhang ◽

Jing Ai ◽

Sainan Peng ◽

...

Keyword(s):

Organic Acids ◽

Extracellular Polymeric Substances ◽

Ferrous Ion ◽

Floc Structure ◽

Effects of calcium ion on sludge conditioning

10.1016/s0273-1223(97)00170-4 ◽

1997 ◽

Vol 35 (8) ◽

Cited By ~ 7

Keyword(s):

Calcium Ion ◽

Pyrite assisted peroxymonosulfate sludge conditioning: Uncover triclosan transformation during treatment

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2021.125368 ◽

2021 ◽

Vol 413 ◽

pp. 125368

Author(s):

Jialin Liang ◽

Liang Zhang ◽

Yan Zhou

Keyword(s):

An application of sludge conditioning and dewatering technique: A case study

Journal of Environmental Science and Health Part A ◽

10.1080/10934529809376742 ◽

1998 ◽

Vol 33 (3) ◽

pp. 461-476

Author(s):

Turgut T. Onay ◽

I. Ethem Gonenç

Keyword(s):

Sludge Conditioning: Effects of Sludge Biochemical Composition

10.2166/wst.1985.0155 ◽

1985 ◽

Vol 17 (4-5) ◽

pp. 505-515 ◽

Cited By ~ 11

Author(s):

P. T. Bowen ◽

T. M. Keinath

Keyword(s):

Lipid Content ◽

Strong Correlation ◽

Biochemical Composition ◽

Carbohydrate Content ◽

Reactive Surface ◽

Low Correlation ◽

Sludge Conditioning ◽

The Difference ◽

Polymer Interaction ◽

Three Components

Variations in response of three different sludges to conditioning with organic polyelectrolytes were evaluated with respect to the carbohydrate, protein and lipid content of the sludges. These biochemicals comprise the surfaces of most sludges. The difference in the concentration of these compounds is intrinsic to the sludge type. Polymer Index (PI) , a measure of minimum polymer dose required to achieve maximum dewaterability, was statistically related to each of the three components. Carbohydrate content correlated most strongly with PI. As carbohydrate content increases, PI was found to decrease indicating better polymer performance. Biopolymers, which are composed mainly of carbohydrates may surround the cells forming a highly reactive surface. These exocellular materials also promote bioflocculation. Both actions result in a lower polymer requirement for destabilizing the sludge. Protein and lipid were not observed to have strong correlation with PI. Cellular surfaces and structures are composed of these components. The low correlation indicates these components are less favored than carbohydrates for polymer interaction.

Effect of surfactant on alum sludge conditioning and dewaterability

10.2166/wst.2000.0137 ◽

2000 ◽

Vol 41 (8) ◽

pp. 17-22 ◽

Cited By ~ 2

Author(s):

J. Ruhsing Pan ◽

C. Huang ◽

C. Gang Fu

Keyword(s):

Water Treatment ◽

Treatment Plant ◽

Water Treatment Plant ◽

Flotation Process ◽

Polymer Addition ◽

Sludge Disposal ◽

Alum Sludge ◽

Sludge Conditioning ◽

Increasing Demand ◽

Co Precipitation

Sludge disposal has become a new challenge for the Taiwan government due to the increasing demand for better quality and greater quantity of water. In some water treatment plants, surfactant has been applied in the flotation process to improve its performance, which suggests the use of surfactant in sludge conditioning. In this study, effects of surfactants on the conditioning of the alum sludge collected from Feng-Yuan Water Treatment Plant were investigated. Surfactants of various charges, namely CTAB and SDS, were added to sludge samples in various amounts, and their effects on sludge dewaterability were evaluated. Surfactants were also added with either cationic or anionic polymers to better understand their effects on the mechanism of sludge conditioning and the feasibility as coagulant aid.Experimental results indicate that applying surfactants alone in sludge system decrease the filterability of sludge, but increase the sludge dewatering rate at optimum dosage. Cationic surfactant was proven possible as conditioning aid for the cationic polymer. The order of surfactant and polymer addition is the key to additive function. On the other hand, when the polymer of opposite charge was added with the surfactant, co-precipitation occurred which resulted in decreased filterability and dewaterability.

Ultrasounds Energy as an Agent of Polyelectrolyte Modification Prior to Sewage Sludge Conditioning

Energies ◽

10.3390/en14196165 ◽

2021 ◽

Vol 14 (19) ◽

pp. 6165

Author(s):

Lidia Wolny ◽

Paweł Wolski

Keyword(s):

Sewage Sludge ◽

Chemical Compounds ◽

Ultrasonic Field ◽

Field Exposure ◽

Field Frequency ◽

Geometrical Characteristics ◽

Sludge Conditioning ◽

Quantitative Changes ◽

Ultrasonic Modification ◽

Shape And Size

The presented research concerned the phenomenon of polyelectrolyte changes resulting from modification by applying the ultrasonic field. The main aim of this research was to determine the activation degree of this macromolecular chemical compound and its effect on sewage sludge subjected to conditioning and followed by dewatering. The overall goal was to investigate the potential way of reducing the dosage of chemical compounds prior to sewage sludge conditioning. The polyelectrolyte samples were sonicated with the ultrasonic disintegrator UD-20 coupled with a sandwich concentrator. The power output of the generator was 180 W and the ultrasonic field frequency was 22 kHz. To describe the geometrical characteristics of the separated phases, the following parameters were determined: surface area (AA), perimeter (LA) and non-dimensional coefficient. With reference to the obtained results, the most significant quantitative changes in shape and size of the separated phases were observed for the ultrasonic field exposure time in the range of 0 to 10 s. This was in agreement with the results observed during dewatering of the investigated sewage sludge. In view of the quantitative analysis of the structure of the polyelectrolyte subjected to the ultrasonic modification, dewatering of sewage sludge was considerably improved by the application of the presented method.