Rinse water Recovery System-METAPure for recovery and reuse of electroplating rinse water.

1. Rinse water Recovery System-METAPurefor recovery and reuse of electroplating rinse water. Pure Tech India, Sf 471/2 Sri Lakshmi Nagar, Thondamuthur road, Coimbatore- 641 046, India. Ph: 91-422-242 6611; Fax:91-422-242 4018 E-Mail: contact@puretechindia.com; website: www.puretechindia.com

2. Electroplating processes and various chemicals used:

3. Important Contributors in a Electroplating Effluent Generation:

4. Treatment processes available: • Chemical treatment using • Sulphuric Acid (pH reduction for chromium conversion) • Sodium Bisulphite (used for converting hexavalent to trivalent Chromium) • Sodium Hypo (Cyanide Oxidation) • Lime/ Caustic (neutralization) • Polyelectrolyte (flocculation) • Clarification (solid- liquid separation) and • Solid sludge separation. • Membrane based physical/physiochemical processes.

5. Conventional Treatment: Electroplating Effluent Oxidation/ Reduction/ Neutralization * Neutralization Precipitation Flocculation (Polyelectrolyte) Waste water discharge Clarification Sludge Storage * : NOTE Cyanide waste: Oxidation Chromium Waste: Reduction Acid/Alkali Waste: Neutralization Dewatering Disposal

6. Membrane Systems An Overview

7. Normal Filtration Cross- flow Filtration Normal Filtration: Water with contaminants pass in direction perpendicular to filter media. The contaminants will choke the pores of the filter media. Cross- flow Filtration: Water with contaminants pass in direction parallel to the filter media. The Outlet from this filtration will have two streams coming out. The concentrate stream will carry along with it the contaminants. The filtered water will come out of a separate outlet. The frequency of filter media getting choked is very low when compared to normal filtration. Filtration: Types and Comparison

8. MF SS UF Macromolecules NF Sugar, DV Salts, DA RO MV Salts, UA Water KEY: SS - Suspended solids DV Salts - Divalent salts DA - Dissociated acids MV Salts - Monovalent salts UA - Undissociated acids Reject portion Permeate portion MF – Micro filtration UF - Ultra filtration NF – Nano Filtration RO – Reverse Osmosis Cross- flow Membrane Processes:

9. Specific advantages of membrane based treatment systems: • Compact and less space occupying. • Marginal chemical consumption (needed in case of pH correction). • Skid mounted systems. • Very low sludge generation. • Very low electricity consumption. • Requires little/ no civil construction. • Separated water is ideally suitable for high quality rinse and bath top up.

10. Reverse Osmosis: Finest form of filtration

11. Osmosis - Reverse Osmosis Illustration: Pressure P Concentrate Dilute Concentrate Dilute Semi- Permeable Membrane Semi- Permeable membrane is one which will allow only water molecules to pass and not salts. In the Left diagram, under normal circumstances, water molecules from dilute solution side will permeate towards concentrate side to form an equilibrium.This is Osmosis and the pressure present is Osmostic pressure. In the right diagram, when a pressure P is applied in excess to the normal pressure , water alone is squeezed into the dilute solution side from the concentrate solution side. This is Reverse- Osmosis.

12. Typical Reverse Osmosis Membranes:

13. Reverse Osmosis Process flow diagram:

14. RO membrane structure:

15. Separated components applications: • Permeate flow (usable/product water flow) • Rinse • Bath top up • Concentrate flow (Reject flow):- • Bath (if the concentrate contains only salts used in the electroplating bath with permissible contaminants)

16. Reverse Osmosis Membranes Rejection Rates:

17. Membrane based Rinse water recovery systems

18. Major contaminants and their removal:

19. Process Flow Diagram Effluent from electroplating process Filtration System Prep Tank Pump Acid/ Alkali addition Permeate tank to process RO based IONICS Unit High pressure pump Reject back to bath/ treatment

20. Low flow membrane systems:

21. High flow membrane systems:

22. A Typical application in electroplating process: Flow of parts Stage 1 Stage 2 Stage 3 Stage 4 Spray-Dip-Spray City Water Rinse High Pressure Rinse Chemical Cleaner Phosphate Dip Flow of parts Stage 5 Stage 6 Stage 7 Stage 8 Stage 9 DI water Spray-Dip-Spray City Water Rinse Spray-Dip-Spray Water Rinse Spray Water Rinse Chromate Dip Spray Rinse RO TO WASTE TREATMENT

23. RO Process in Nickel Plating evaporation RINSE # 1 RINSE # 2 PLATE parts parts feed RO permeate concentrate 95% recovery Make-up (Pure water)

24. Benefits: • 70% of rinse water can be recovered and reused for Bath Top up and as Rinse water. • Pollution Problem solved • The cost of treatment is got back to by way of water which can be reused for rinsing process. Customers: • Silver Crown Electroplaters: 100 and 200 LPH • Divya Engineering : 10 LPH • Sundaram Fasteners, Padi, Chennai: 200 LPH

25. Other Electroplating Process related Products: • Desorber: Oil water separator for Degreasing Baths. • OleoSepa: Desorber, Ultrafiltration System for complete oil removal and reuse of Degreasing solutions. • Bag Filtration System: For filtering suspended solids upto 1 microns for your plating baths. Filter media can be offered in Stainless Steel, Polypropylene and HDPE wire cloths. Complete unit can be fabricated in the above materials. • RO Plant: For removing Total Dissolved Solids in water used for bath and rinse for better efficiency of plating.

26. Thank You Pure Tech India Address : SF 471/2, Sri Lakshmi Nagar Thondamuthur Road Coimbatore – 641 046 Phone : 91- 422 – 242 6611 Fax : 91- 422 – 242 4018 Email : contact@puretechindia.com Web : www.puretechindia.com