scholarly journals INFLUENCE OF FLOCCULANT TYPE ON STRENGTH CHARACTERISTICS OF FLOCS IN CLAY-SALT SUSPENSIONS

2020 ◽  
Vol 63 (6) ◽  
pp. 30-36
Author(s):  
Olga R. Seredkina ◽  
Olesya V. Rakhimova ◽  
Sergey V. Lanovetskiy
Keyword(s):  
Strength Characteristics ◽  
Ionic Polymers ◽  
Partial Restoration ◽  
Anionic Polymers ◽  
Cationic Flocculant ◽  
Potential Possibility ◽  
Floc Strength ◽  
Cationic Copolymers ◽  
Hydrodynamic Effects ◽  
Flocculated Suspension

The results of studies on the effect of the flocculant type on the strength characteristics of floccules in clay-salt suspensions, obtained using a laser analyzer of particle size Lasentec D600L FBRM systems were presented in the article. The coefficients of strength and reduction of aggregates formed by polyacrylamide and its anionic and cationic copolymers were determined. Increasing the speed of mixing by using of polymers various types leads to the destruction of the formed aggregates in the flocculated suspension. The size of flocs induced by a cationic flocculant is reduced from 250 to 110 mm, for anionic and non-ionic flocculants - from 500 to 250 mm. The dependence of floc strength on the macromolecules adsorption mechanism on a solid surface was established. The decrease in hydrodynamic effects entails the partial restoration of floccules. It was shown that the recovery of flocs for all studied polymers was limited, which indicates a significant irreversibility of the aggregates destruction process. When using cationic flocculant, the ability to restore the aggregates is 2.5 times lower compared to anionic and non-ionic polymers. For nonionic and anionic polymers, the dependence of flocs coefficients of strength and recovery on the flocculant dosage was established. Dosage of cationic polymer does not affect these indicators. The dynamics of flocculation, destruction and reflocculation processes using various flocculants was considered. The influence of the charge type and polymer consumption on the mechanism of particles interaction was established. The potential possibility of using the obtained results to improve the technology of potassium chloride production at the stages of thickening and dehydrating clay-salt sludge was shown.

Formation and breakage of flocs using dual polymers

2006 ◽  
Vol 53 (7) ◽  
pp. 217-223 ◽  
Author(s):  
M.A. Yukselen ◽  
J. Gregory ◽  
E. Soyer
Keyword(s):  
Shear Rate ◽  
Test Procedure ◽  
Optical Monitoring ◽  
Ionic Polymers ◽  
Ionic Polymer ◽  
Polymer Addition ◽  
Anionic Polymers ◽  
Jar Test ◽  
Average Shear ◽  
Floc Strength

The effect of shear on the formation and break-up of flocs generated using cationic, anionic and non-ionic polymers, and dual combinations of these, has been investigated using conventional jar test procedure and by continuous optical monitoring. The breakage of flocs was followed at a high stirring speed, corresponding to average shear rate (G) of approximately 520 s−1. Most of the breakage occurred within a few seconds of increasing the shear rate. After each breakage, the stirring rate was reduced to the original value of 50 rpm (G≈23 s−1) to allow the flocs to regrow. For cationic–anionic polymers case, the regrowth of flocs was fully reversible and the breakage factors were smallest indicating highest floc strength. In contrast, flocs formed using non-ionic polymer together with anionic or cationic did not produce as strong flocs. It is found that the sequence of polymer addition is not very significant for floc formation and reformation when the cationic–anionic dual system is used.

The use of selective and direct DAF for removal of particulate contaminants in drinking water treatment

1995 ◽  
Vol 31 (3-4) ◽  
pp. 49-57 ◽  
Author(s):  
James P. Malley
Keyword(s):  
Drinking Water ◽  
Drinking Water Treatment ◽  
Cationic Polymers ◽  
Ionic Polymers ◽  
Charge Reversal ◽  
Dissolved Air Flotation ◽  
Polymer Addition ◽  
Anionic Polymers ◽  
Particulate Contaminants ◽  
Dissolved Air

Cationic polymers were found to coat bubbles resulting in charge reversal and increasingly positive EPM. Batch bench-scale dissolved air flotation (DAF) studies show promising benefits from the addition of cationic or non-ionic polymers to the saturated recycle line of conventional DAF. In cases where low turbidity, low color waters are being treated, direct DAF compared well with conventional DAF. Polymer addition improved the percentage solids of the float. Anionic polymers were not found to be effective. Further research at the pilot and full-scale is needed to verify these findings.

scholarly journals IN SITU OPTHALMIC GEL WITH ION ACTIVATED SYSTEM

2019 ◽  
pp. 15-18
Author(s):  
Insan Sunan Kurniawansyah ◽  
Taofik Rusdiana ◽  
Habibah A. Wahab ◽  
Anas Subarnas
Keyword(s):  
Drug Delivery ◽  
Gellan Gum ◽  
Prolonged Release ◽  
Osmotic Gradient ◽  
Scientific Journals ◽  
Ionic Polymers ◽  
In Situ Gel ◽  
Anionic Polymers ◽  
In Situ Gelation

In situ gel with ion activated system which occurs as triggered by a change in the ionic strength. Osmotic gradient is a factor that determines the rate of gelation on the surface of the gel. Polymers play an important role in drug delivery from their dosage forms. Polymeric in gelling systems provides longer drug release compared to conventional delivery systems. The use of biodegradable and biocompatible polymers for in situ gel formulation makes the drug delivery system acceptable and controlled. Thus the continuous and prolonged release of the drug, biocompatibility characteristics makes the dose gel form in situ reliable. Polymers that are used in ion activated in situ gelation can be various, such as gelrite gellan gum, alginates, deacetylated gellan gum, anionic polymers (carbopol), cationic polymer (chitosan), non-ionic polymers (HPMC, Methylcellulose), thiolated polymer (thiomers), carbomer (polymer used in ophthalmic), polycarbophil (polymer used in ophthalmic). This review is written based on the data or information obtained by using several search engines and several scientific journals, using the keywords in situ gel with polymers, ion activated the system, and limited search years in 2010 and above.

Evaluation of floc strength by morphological analysis and PDA online monitoring

2007 ◽  
Vol 56 (10) ◽  
pp. 117-124 ◽  
Author(s):  
Pengkang K. Jin ◽  
Xiaochang C. Wang ◽  
Haixia Chai
Keyword(s):  
Morphological Analysis ◽  
Online Monitoring ◽  
Particle Dispersion ◽  
Force Coefficient ◽  
Floc Size ◽  
Binding Force ◽  
Jar Test ◽  
Floc Strength ◽  
Series Of Experiments ◽  
Flocculated Suspension

This paper established a method for the evaluation of floc strength by morphological analysis and PDA online monitoring. Theoretically, the binding force of a floc can be expressed as B=k1d2Df/3, where k1 is a coefficient, d is floc size and Df is the fractal dimension of the floc. In order to calculate the binding force under a given flocculation condition, a jar test was conducted and d and Df were measured by image analysis. A shear force was exerted on the grown flocs by introducing the flocculated suspension through a transparent tube where the velocity gradient value of the flow could be accurately controlled. As the tube was connected with a particle dispersion analyzer (PDA), the condition of floc breakage was online monitored and the critical condition was identified by analyzing the PDA outputs (FI curves). The binding force coefficient k1 could thus be determined, and the binding force B which represented the floc strength was evaluated. The validity of this method was proved by a series of experiments using aluminium sulphate as coagulant for the flocculation of humic substances.

scholarly journals A reversible B–A transition of DNA duplexes induced by synthetic cationic copolymers

2016 ◽  
Vol 52 (47) ◽  
pp. 7446-7449 ◽  
Author(s):  
Nonoka Yamaguchi ◽  
Yu-ki Zouzumi ◽  
Naohiko Shimada ◽  
Shu-ichi Nakano ◽  
Naoki Sugimoto ◽  
...  
Keyword(s):  
Dna Duplexes ◽  
Anionic Polymers ◽  
Cationic Copolymers

Reversible B–A transitions of DNA duplexes were induced by synthetic cationic and anionic polymers.

scholarly journals Evaluation of a Novel Polymeric Flocculant for Enhanced Water Recovery of Mature Fine Tailings

Processes ◽  
2020 ◽  
Vol 8 (6) ◽  
pp. 735
Author(s):  
Kyle C. Lister ◽  
Heather Kaminsky ◽  
Robin A. Hutchinson
Keyword(s):  
Hydrolytic Degradation ◽  
Process Water ◽  
Poly Lactic Acid ◽  
Water Recovery ◽  
Water Release ◽  
Anionic Polymers ◽  
Cationic Flocculant ◽  
Mature Fine Tailings ◽  
Fine Tailings ◽  
The Impact

The novel cationic flocculant, poly(lactic acid) choline iodide ester methacrylate (poly(PLA4ChMA)), has been shown to provide improved flocculation of 5.0 wt.% mature fine tailings (MFT) diluted in deionized water compared to commercial anionic polymers, with continued dewatering of the sediment occurring as the polymer undergoes partial hydrolytic degradation. However, the elevated dosages (10,000 ppm) required would make the polymer costly to implement on an industrial scale. With this motivation, the impact of MFT loading and the use of process water is explored while comparing the settling performance of poly(PLA4ChMA) to available commercial alternatives such as anionic FLOPAM A3338. Improved consolidation of 5.0 wt.% MFT diluted with process water could be achieved at reduced dosages (500 ppm) with poly(PLA4ChMA). However, the final compaction levels after polymer degradation were similar to those achieved with the nondegradable commercial flocculants. Flocculation-filtration experiments with undiluted MFT are also conducted to compare the performance of the polymers. Significantly faster rates of water release were observed with the cationic flocculants compared to FLOPAM A3338, but no improvement in the overall tailings compaction was found either before or after poly(PLA4ChMA) degradation. Thus, the improved dewatering observed with poly(PLA4ChMA) in dilute MFT suspensions does not extend to conditions that would be encountered in the field.

scholarly journals COMPATIBILITY SCREENING OF VIDAGLIPTIN WITH IONIC AND NON-IONIC POLYMERIC EXCIPIENTS FOR THE DESIGN OF EXTENDED RELEASE DELIVERY SYSTEM

2021 ◽  
Vol 9 (04) ◽  
pp. 187-193
Author(s):  
Balen Saharia ◽  
◽  
Gouranga Das ◽  
Bipul Nath ◽  
◽  
...  
Keyword(s):  
Extended Release ◽  
Cationic Polymers ◽  
Ionic Polymers ◽  
Release Formulation ◽  
Pharmaceutical Dosage Forms ◽  
Clinical Phase ◽  
Extended Release Formulation ◽  
Anionic Polymers ◽  
Nonionic Polymers ◽  
Physical And Chemical

Studies of drug-polymer compatibility play an important role in the preformulation stage for the development of pharmaceutical dosage forms. The potential physical and chemical interactions between drugs and polymer can affect the chemical nature, stability and bioavailability of the dosage form and as a result in the therapeutic response in the clinical phase. The present study reveals the thermal and spectroscopic study of physical mixtures of Vildagliptin (VDG) and HPMC in combination with cationic polymers chitosan, anionic polymers NaCMC and nonionic polymers PEO for extended release (ER). In the first phase of the study, differential scanning calorimeter (DSC) was used as tool to detect any interaction. In the next phase, a Fourier Transform Infrared Spectroscopy (FT-IR) technique was used to confirm and to investigate the type of the possible interactions between the components. In both cases, the spectroscopic data revealed that the analysed polymeric excipients did not show any affect on the VDG. Results of the present study indicated the suitability of the HPMC K4M hydrophilic matrix polymers in combination with cationic polymers, anionic polymers and non-ionic polymers in the preparation of extended release formulation of VDG.

Study of operating properties of aanticorrosion packing papers

2020 ◽  
Vol 76 (10) ◽  
pp. 1021-1027
Author(s):  
A. P. Ponomarev ◽  
L. G. Kolyada ◽  
E. V. Tarasyuk
Keyword(s):  
Steel Strip ◽  
Low Carbon Steel ◽  
Strength Characteristics ◽  
Low Carbon ◽  
Operating Characteristics ◽  
Packing Materials ◽  
Accelerated Corrosion ◽  
Operating Properties ◽  
Deformation And Strength Characteristics ◽  
Anticorrosion Properties

Metal products are subjected to atmospheric corrosion during transportation and storing. An important way to prevent this negative phenomenon is application of special packing materials, in particular materials, containing volatile inhibitors of corrosion, which protect metal against various corrosion agents. To protect metal effectively it is necessary to provide a definite level of operating characteristics of packing materials. The purpose of the work was the study of operating properties of inhibited crepe, inhibited and laminated polyethylene film, inhibited crepe and reinforced by polypropylene web papers, manufactured by OJSC “PP TechnoKhim”, Magnitogorsk, used for packing of metals. Structural and dimensional, sorption, deformation and strength characteristics, of the studied anticorrosion papers are presented, the characteristics being calculated based on the results of measurements. To determine their physical-mechanical and anticorrosion properties, standard methods and methodologies were used. To evaluate impact of moisture and transportation conditions, indices of water adsorption and wear of the studied papers were determined. Inhibitor content in these materials was determined by thermogravimetric analysis method. Their protective ability was studied on samples of low carbon steel strip. For accelerated corrosion tests the strip samples were degreased by alcohol, dried in air and packed in the studied anticorrosion papers, after that they were exposed under increased temperatures and moisture conditions. It was determined, that among the materials under the study, the inhibited crepe paper, reinforced by polypropylene web, hhas the best complex of physical-mechanical and anticorrosion properties. It provides a higher level of prevention corrosion of metal l and surpasses other materials in a number of deformation and strength characteristics. Recommendations were proposed to improve qquality of produced anticorrosion papers.

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