Introduction
Wastewater containing Nickel salts originates from many industrial sites such as:
- Plating industry/industries
- Hydrogenation process from fatty oil industries
- Silver refineries
- Steel works and foundries
- Aircraft industry
- Motor Vehicle industry
Electroplating wastewater is the most common source of nickel compounds. Wastewater resulting from pickling and plating of nickel alloys pose for more problems. In treatment than in the case for other plating material, such as copper. This may be due to the presence of wide spectrum of nickel alloys and variety of pickling liquor use. In the production of electroplating articles 10-90% of the plating metals are discharged in the form of effluents rather than being deposited on the work pieces. The need of the metals all over the world is increasing but the existing deposits are depleting.
In the near future,processing of poor grade ores and recycling of previously used metals will gain considerable importance. Attempts have been made particularly for metals like copper and nickel. The removal or recovery of these metals has received wide attention.
Treatment Technologies
- Precipitation
- Ion Exchange
- Reverse Osmosis
- Evaporation Recovery
Ion Exchange process
The wastewater containing soluble nickel, after giving pretreatment can be recovered by using a cation exchange resin. The use of ion exchange resin has an advantage for removing only metallic constituents from wastewater. Thus the outlet water can be reused or it can be used/discharged after giving treatment. Nickel which is on the resin can be eluted with sulphuric acid of about 10-20% solution and the nickel conc in the range of 50-100 mg/l can be obtained. Nickel is thus recovered as nickel sulfate and reused to load the plating baths.
Benefits of Ion Exchange Resins
- Ease of operation
- Highest overall recovery of nickel as nickel sulfate
- Reuse of treated water
- Recovered fractions can be directly reused/recycled
- More reliable and cost efficient.
The use of Ion Exchange resin also provides the system where purity of metals can be obtained.Ion exchange resins help to separate (removal) and recovery of the metals.
Potential Clients
- Bajaj Auto Ltd, Pune
- Premier Automobiles, Mumbai
- Telco, Pune
- Escort , New Delhi
- Maruti Udyog Ltd., New Delhi
- Hindustan Motors, Calcutta
- Hero Honda
- Mahendra and Mahendra
- Ind. Suzuki (TVS)