Inexpensive removal and recovery of contaminants like heavy metals from effluent streams and ground water using polymer-surfactant flocculants that settle with gravity.
Current waste water treatments
Industrial processes can result in contaminants in the effluent stream. For example, zinc, cadmium and chromium contaminations from plating processes. Present remediation techniques involve expensive and inefficient chemical precipitation and adsorption processes. Alternative treatments like ultrafiltration, reverse osmosis and ion exchange are time consuming and have significant energy requirements.
Novel materials used to pull contaminants out of solution
At the heart of this technology is a novel material that comprises a complex of polymers and surfactants that trap contaminant ions. This process is known as complexation and flocculation. Gravity then settles the flocculants, separating the contaminants from the water. The flocculants can then be treated separately to recover the contaminants in a concentrated form. The constituent polymer can also then be recycled without a deterioration of removal ability in the next cycle.
Advantages of the process
Compared with existing treatment solutions, this system has:
• an efficient removal system
• low cost implications
• reliable performance
• straight forward usage
• fast reaction times
The system is capable of removing a high percentage (95-99%) of the multivalent metal ions, such as Zn(II), Cd(II) and Cr(III), contained within dilute (10mg/L) solutions by using a small amount of polymer and surfactant. The polymers and surfactants used are commercially available, safe and inexpensive.
The method has been shown to be effective on a number of heavy metal contaminants and more are currently being tested. The underlying technology is the subject of a UK patent application. Companies interested in applying this process for industrial and ground waste water treatment are invited to contact Oxford University Innovation.