Study on Macroscopic Aggregation of Silica Suspensions and Sewage

Smoczyński, L.; Wardzyńska, R.

doi:10.1006/jcis.1996.0551

Cited by 11 publications

(4 citation statements)

References 1 publication

(1 reference statement)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The computer simulation employed in this work is based on a semi‐empirical concept, developed through extensive laboratory experience in such areas as chemical coagulation, electro‐coagulation and aggregation (Smoczynski and Wardzynska, 1996; Wardzynska et al, 2007) carried out in both natural and model systems. The input data do not contain any value of the particle charge and each “attachment” of the “sol” particles to the “coagulant” particle is irreversible.…”

Section: Methodsmentioning

confidence: 99%

“…Coagulation, aggregation, flocculation and sedimentation processes are usually investigated in natural systems, such as wastewater (Smoczynski and Wardzynska, 1996) model systems including silica suspensions (Smoczynski, 2000; Lee et al, 2002; Hong et al, 2009) as well as computer‐simulated systems (Yang and Biswas, 1999; Evilevitch et al, 2002; Ratnaweera et al, 2002; Smoczynski et al, 2009a, b). Computer‐based simulations that account for short‐range attractive forces and long‐range repulsive forces (Romero‐Cano et al, 2000; Stradner et al, 2004; Richardi, 2009) in a pulsed system usually describe molecular collision models, the mechanism of latent, slow and rapid coagulation, the aggregation mechanism, as well as the conditions and the kinetic parameters of those processes (Elimelech et al, 1995; Ehrl et al, 2009; Kovalchuk et al, 2009; Siddique et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Computer simulation of the polydispersive sol coagulation process

2012

View full text Add to dashboard Cite

This work reports on a computer-simulated investigation of the coagulation rate for a system comprising spherical sol and coagulant particles. The discussed experiment positively verified the functioning of the simulated coagulation system, where the aggregation process proceeds in line with the particle-cluster model as a rapid and perikinetic coagulation process that satisfies the Smoluchowski equation. The rate of the simulated coagulation process satisfies kinetic equations for both first-order and second-order reactions. Selected concepts and models of the coagulation theory have been also verified.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Computer simulation of the polydispersive sol coagulation process

2012

View full text Add to dashboard Cite

show abstract

“…Filling the space with the mass of a sludge floc can be defined with the fractal dimension, D f , previously defined in Equation (2). There are more data available [19,29,[46][47][48] on the fractal dimension values of various types of flocs, including the values of D f in sludge of municipal wastewater. Depending on the measurement method applied, the type of a coagulant and other parameters of the process, the values of D f can be equal with the following values: 1.72 [19] [48].…”

Section: Propertiesmentioning

confidence: 99%

Study of Sludge Particles Formed during Coagulation of Synthetic and Municipal Wastewater for Increasing the Sludge Dewatering Efficiency

Smoczyński

Kalinowski

Creţescu

et al. 2019

Water

View full text Add to dashboard Cite

Municipal wastewater sludge was produced by chemical coagulation of synthetic wastewater (sww) based on Synthene Scarlet P3GL disperse dye and real municipal wastewater (nww), coagulated by commercial coagulants PAX (prepolymerised aluminum coagulant) and PIX (a ferric coagulant based on Fe2(SO4)3). An attempt was made to correlate the sludge’s dewatering capacity (in terms of capillary suction time—CST) with operation parameters for wastewater treatment, size distribution and specific surface area of the sludge particles. It was found that the presence of phosphate ions in the system facilitates the removal efficiency of the above-mentioned dye (L) due to the interaction between the dye molecules and H2PO4− ions. Unlike sww, negatively charged organic substances (sorg) in nww are directly adsorbed on the surface of colloidal particles {Fe(OH)3} and {Al(OH)3} (prtc). It was also discovered that an increase in the dose of a coagulant led to an increase of CST for sww sludge and to a decrease of CST for nww sludge. It has been suggested that flocs composed of spherical {Al(OH)3} units possessed more internal space for water than aggregates consisting of rod-shaped {Fe(OH)3} units and, consequently, it is more difficult to remove water from Al-sww sludge than from Fe-sww. The results obtained showed that smaller particles dominate in sww sludge, while larger particles are prevalent in nww sludge. To explain this distinct difference in the size distribution of particles in sludge obtained with the use of Al3+ and Fe3+, simple models of aggregation and agglomeration-flocculation processes (aaf) of treated wastewater have been proposed. Except for PIX in nww, the analyzed particles of the investigated types of sludge were characterized by similar specific surface area (Sps), regardless of the kind of sludge or the applied coagulant. Slightly larger, negatively-charged sorg bridges, anchored directly on the surface of positive prtc are more effective in closing the structure of nww sludge than small L bridges of the dye molecules anchored on the surface of prtc via H2PO4−. All the discovered aspects could lead to improved performance of wastewater treatment plants (WWTP) by increasing the efficiency of sludge dewatering.

show abstract

“…A differentiation of the D value for different sludge components may be an indicator of the mechanism of their formation process [ 20–24 ]. The results of laboratory experiments [ 25 ] showing, for example, the impact of a coagulant dose of the mean D of post-coagulation aggregate-flocs [ 26 ] are known.…”

Section: Introductionmentioning

confidence: 99%

Modelling the structure of sludge aggregates

Smoczyński

Ratnaweera

Kosobucka

et al. 2015

Environmental Technology

Self Cite

View full text Add to dashboard Cite

The structure of sludge is closely associated with the process of wastewater treatment. Synthetic dyestuff wastewater and sewage were coagulated using the PAX and PIX methods, and electro-coagulated on aluminium electrodes. The processes of wastewater treatment were supported with an organic polymer. The images of surface structures of the investigated sludge were obtained using scanning electron microscopy (SEM). The software image analysis permitted obtaining plots log A vs. log P, wherein A is the surface area and P is the perimeter of the object, for individual objects comprised in the structure of the sludge. The resulting database confirmed the ‘self-similarity’ of the structural objects in the studied groups of sludge, which enabled calculating their fractal dimension and proposing models for these objects. A quantitative description of the sludge aggregates permitted proposing a mechanism of the processes responsible for their formation. In the paper, also, the impact of the structure of the investigated sludge on the process of sedimentation, and dehydration of the thickened sludge after sedimentation, was discussed.

show abstract

Study on Macroscopic Aggregation of Silica Suspensions and Sewage

Cited by 11 publications

References 1 publication

Computer simulation of the polydispersive sol coagulation process

Computer simulation of the polydispersive sol coagulation process

Study of Sludge Particles Formed during Coagulation of Synthetic and Municipal Wastewater for Increasing the Sludge Dewatering Efficiency

Modelling the structure of sludge aggregates

Contact Info

Product

Resources

About