Flocculants
FLOCCULANTS
Polyelectrolyte Flocculants are Polyacrylamide base water soluble Polymers with low to high molecular weight.
Flocculants means the agglomeration of particles into larger unit. As the particle size increases, it facilitates separation of solid constituents from liquid by process such as
(a) Sedimentation (b) Floatation (c) Filtration (d) Centrifugation etc. Flocculants are Separated significantly in solution of widely varying pH chemical contents or temperature.
SELECTION OF FLOCCULANTS
For successful treatment of any suspension, it is necessary to find out efficient Flocculants. The testing of suitable grades of Flocculants can be carried out from laboratory method using filtration, sedimentation and thickening of solid test and by observing fast settling rate and size of flock formation.
PROCEDURE FOR USE OF FLOCCULANTS:
For maximum efficiency, solution of flocculants can be diluted from 0.05% to 0.5% in powder form, while jelly form is diluted from 0.5% to 5% before addition to process stream.
To get maximum effect on flocculation some of the important precautions should be taken such as:
(1) Solution of flocculants should be diluted to 0.5% of powder form and 1% of jelly form before addition.
(2) While preparing flocculating solution stirring should not exceed more than 100 rpm.
(3) At the addition point and thereafter, there should be no agitation because it will break a flocculants chain. Once a chain formation starts, there should not be any agitation to break the flocks.
(4) Keep prepared solution at least for 30 mins. Before addition to get maximum efficiency.
HOW TO USE FLOCCULANTS? (SOLUTION PREPARATION)
SOLUTION CONCENTRATION:
Prepare 1 GPL (GRAMS PER LITRE) solution i.e.; 100 gm flocculant in 100 litre water tank while preparing the solution, maintain continuous stirring and sprinkle flocculant powder on water surface. Keep stirring till no transparent particles are visible. The solution concentration for jelly is 10 GPL solution.
DOSAGE:
The optimum effective flocculant dose largely depends on the solid content and the nature of slurry. The optimum dose of flocculant is in the range of 1 to 5 ppm of powder form and 1 to 50 ppm in jelly form.
SPECIFICATIONS (PROPERTIES):
Polyelectrolyte Flocculants are available in powder form as well as in jelly form.
POWDER JELLY
Appearance Free flowing amorphous powder. Thick viscous liquid.
Density 0.8 gm/cc 1.04 to 1.06 gm/cc.
Colour White / off white Colourless.
Shelf life More than one year 3 to 5 months.
ADDITIONAL APPLICATIONS OF FLOCCULANTS
Flocculants are used in many industries for various applications e.g.
(A) Sugar industries: For purification of sugarcane juice known as mud settling.
(B) Petroleum industry: For demulsification, floatation and clarification of effluents.
(C) Copper, Zinc, Iron Ore & Rock phosphate: For ore dressing, BENEFICIATION & clarification of effluents.
(D) Coal mining: For recovery of fines, clarification & BENEFICIATION.
(E) Water Treatment.
(F) Alum Industries.
(G) Pulp & Paper Industries.
(H) Caustic soda industries.
(I) Borax & Boric Acid industry.
(J) Paint industries.
(K) Cement/ Asbestos industries.
(L) Phosphoric Acid industries.
(M) Effluent Treatment.
STORAGE INSTRUCTIONS
Polyelectrolyte Flocculants should be stored in airtight containers to avoid contamination of moisture.