PAC Technology & Application

[ Different production process ]
Spray dried process:
Liquid process —Plate-and-frame pressure filtration —Spray tower drying —Finished product



Generall dried process:
liquid-making process—free setting —roller drying—finished product



[ Features of spray dried process ]
The features of pressure type spray dried method is determined by the operating principle of pressure type atomizer. The output product after pressure type spray dried process is porous fine particle or hollow fine particle, which shows the features of superiors dustproof and flowing property. Owing to its bigger contact area between itself and surrounding water than other powder products, it shows better wettabiliy and quicker water purifying speed.Spray granulation is to dry polyaluminium chloride and atomize to be minute particle simultaneously.




Poly aluminium chloride is water soluble substance and shows features of good thermal stability and high solubility .Polyaluminium chloride solution with 40-50% solid content on drying is introduced to high pressure pump, atomized in atomizer of dryer to be minute fogdrop which is the dried to be granular products. Dehydration and granulation are made simultaneously in this process.

[ Application ]
PAC is a kind of inorganic macromolecule flocculant. Through the hydroxyl ion bridging function and the polyvalent anion polymeric function, it produces large molecular and high electricity inorganic macromolecule. It adapts a wide PH range of 5.0~9.0, and the best is between 6.5~7.6.
1) Purification of river water, lake water and underground water
2) Purification of industry water and industry recycling water.
3) Purification of waster water
4) Reclaiming coal from coal-washing waste water and kaolin in ceramic industry
5) Purification of the waste water in printing and dyeing industry, leather industry, brewage industry, meat-processing industry,
coal-washing, metallurgy industry, mine, pharmacy, paper-making, and purification of the waste water containing fluorine, oil and heavy metals
6) Tannage and cloth cockling-prevent
7) Cement Solidifying, and moulding
8) Refining of pharmaceuticals, glycerine and sugar
9) Catalyzer carrier
10) Paper-making glue


 

[ Application Methods ]
No standard dosage rate can be recommended. Optimum dosage rate and best place of addition should be determined by onsite trials.
1. The liquid product can be dosed directly or dosed after dilution. As for the solid product, dilution is necessary before being dosed. Water amount for dilution shall be determined based on the amount of the chemical to be dosed and the quality of water to be treated. Dilution proportion for solid product is 2%-20%, and for liquid product, 5%-50%(based on weight percentage).
2. The dosage of the liquid product is 3-40g/MT and the dosage of the solid product is 1-15g/MT. The specific dosage is based on the flocculation test and on the trial.
3. Its acidity is lower than other inorganic coagulants.

[ Different constitutive material decides the water-purifying effect ]
The three primary indicator PAC, AL2O3 content,basicity and water soluble substance.
In the spray drying process,nozzleuniformly spray mother liquid in the drying tower,which ensure AL2O3 is uniformly and stable and easily controlled within target zone, improve adsorptivity of colloidal particle and make coagulation and flocculation effect, which is unmatched by other drying process.
2.Basicity namely polymerization degree directly influence water treatment effect. Adoption of pressure type particle spray-drying process can increase product polymerization degree in the situation of maintaining activity of mother liquid.Futhermore,basicity can be adjusted according to different water quality for product manufactured through spray-drying process, whereas product manufactured through roller drying process is liable to break polymerization degree, with only very small basicity range ,and adjust to limited water quality.
3.Owing to adopting plate frame pressure filtration technology,solid water nonsoluble substance are controlled within 0.3 and liquid water nonsoluble substance within 0.1, which ensure the smoothness of clients pipe, and this is unattainable by free setting process.

[ Different composite cost ]
Products manufactured through spray drying process show features of high stability, adaptation to wide water area, quick hydrolysis speed, strong absorptivity, big flocs, quick precipitation, low turbidity out of water and superior dehydration property. Spray drying products are needed less than other products for the treatment of same water quality,and especially for seriously polluted water, Spray drying products are only needed half less than roller drying products, which can not only decrease worker`s labor intensity, but also reduce clients`water cost. Besides, spray drying products can avoid water accident, and are more safe and reliable for drinking.

[ Advantages & Features ]
Compared with other coagulants,this product possesses the following advantages.
1.Wider application, better water adaptation.
2. Quickly shape big alum bubble, and with good precipitation.
3. Better adaptation to PH value(5-9),and little declining range of PH value and alkalinity of water after treatment.
4. Keeping stable precipitation effect at lower water temperature.
5. Higher alkalization than other aluminium salt and iron salt, and little erosion to equipments.

[ Usage ]
In order to achieve optimum flocculation effect and lowest cost,you can determine the optimum product input proportion through tests according to different raw water turbidity, change of seasons and shapes of pond. Liquid products should be mixed to 5-10%aqueous solution,and solid products should be mixed to 3-5%aqueous solution. The higher is the turbidity of the raw water ,the thinner is the solution mixed, and you can increase the product input and get better flocculant effect.