Multifunctional flocculants powders (MFP) application is addressed to the wastewater depuration process in small and medium dimension plants (less than 20 cubic meters/day).
The powders are "all in one" products and contain primary flocculants, polymers, dispersants, wetting agents, anti-caking agents, activated carbon and absorbing clays : all these components in micronized form.
MFP must be added as it and stirred in a period of 3 - 5 minutes in a pH range 8 - 9.
No pre-dilution, pre-dispersion, or other previous operation is required.
After such period it occurs the formation and sedimentation of big flocks and the liquid becomes clear without residual solids in suspension. By this method it´s possible to obtain the following advantages:

• Saving in the costs of dosage equipment
• Management of depuration proceedings by not specialized workers
• Reduction of the treatment costs
• Complete clarification of the waste water
• Reduction of COD
• Reduction of Tensides content
• Possibility of reuse of the water
• Formation of easy to remove sludge

Multifunctional flocculants powders are suitable for the wastewater difficult to be treated by alternative treatments, produced by the following industries:

• Galvanic Industry
• Adhesives Industry
• Cosmetic and Tensides Industry
• Textiles Industry
• Ceramic and Glass Industry
• Cooling Lubricants Industry
• Dyeing Auxiliaries for Paper and Textiles Industry
• Emulsion and Dispersion Paints Industry
• Glues Industry
• Graphic Industry
• Plastic Articles (Injection - Moulding) Industry
• Metal Surface Treatment Industry
• Printing Inks and Ausiliaries Industry

The feeding devices are automatic and requires the use of a screw connected to a timer to allow a suitable dosage, a stirred vessel and a filtration equipment by means draining bags or a paper filter.

The use of such products allows a treatment without storage tanks, pH control, dosing pumps etc, so the depuration cycle is easier and can be carried out in batches or in continuous, depending on the volume of the wastewater.

Application Method

1. pH CONTROL
   Before to use HYPOL PWD range, it´s necessary always to control pH value.
   The best pH value range is between 7,8 - 8,5.
   PH adjustment is carried out with lime in slurry
   An acidic pH range does not allow the first flocks formation and a to basic pH leads to opalescent water at the end of the treatment.
    
2. Dosing Devices
   HYPOL PWD range must be added as it. Usually in the plant the dosage feeding devices is a screw connected with a timer to calculate a working time more suitable for the wastewater characteristics. The product is mixed with the wastewater in a batch or continuous process.
   The water to be treated must be well stirred to avoid the formation of product caking and lumps formation.
    
3. Reaction Time
   A stirring time of 3/4 minutes is usually adequate to complete the reaction.
   At the beginning, it occurs the formation of small dimension flocks. In few minutes the flocks increase the dimension and a fast sedimentation occurs.
    
4. Time of Sedimentation
   After the reaction time, the stirring is stopped to allow the sedimentation.
    
5. Sludge Filtration
   After sedimentation the settled sludge is collected in various plant options : draining bags, paper belt, press filter. Usually the plants suitable for this application are automatic and have a treatment capacity from 500 lt to 20,000 lt/day.

In this paper are reported some application examples for wastewater showing a strong difficulty to be treated in conventional way.

Application 1 :
Wastewater from Resins and Glues

Application 2 :
Wastewater from Metalworking and Penetrating Fluids

Application 3 :
Treatment of Wastewaters Containing Inks

Application 4 :
Wastewater Treatment of Water Based Paint Washing Equipment

Conclusions

A wide range of formulations in Multifunctional Floculants Powders allow to apply such technology in many wastewater depuration cycles. Contemporarily, the high automation in plant increases the possibility to use an additive in powder form in a process without storage, dosing pump, complex instrumentation.

Such method is a technological advancement of the classical sedimentation plant and by such way the removal of COD, Tenside, Colours, oils etc can be strong increased.

The final result is usually satisfactory and can be optimised depending on the opportunity or necessity to save the water by a complete reuse.

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