Heavy metal precipitants and changing consent levels: a case study
We recently worked with a client whose consent to discharge dissolved heavy metal precipitants was set to change. Read on to find out how we worked with them to identify a solution…
The client
As a business that involved processing granite, the effluent produced contained a mixture of both solid and dissolved heavy metal precipitants including aluminium, nickel, phosphorus and iron.
The client recycled process waters using an automated treatment plant with lamellar clarifier, flocculants & coagulants and a chamber filter press, with a high percentage of solids removed from the system.
The problem
As we predicted earlier this year, consent to discharge levels for heavy metal precipitants are being lowered, as The Environment Agency aims to reduce the impact of metals in our water systems.
Subsequently, the client’s water supplier had tasked them with reducing their water trade effluent metal content by 50%-75%, with particular focus on nickel.
The solution
After consulting with the client, we modified the existing treatment to include the use of a high molecular weight chelating polymer, which forms strong, insoluble chelate complexes.
The polymer bonds directly to the metal, forming an insoluble complex. It can remove metals from complexes directly without having to pre-treat e.g. metal-EDTA complexes.
By using polymer, metals can be removed to concentrations of <0.1mg/l.
The future
With the Environment Agency’s powers to sanction non-compliance set to increase, now is the time to make sure your water trade effluent treatment systems are working to their optimum.
Experts like Aqua Advice can help businesses meet these new compliance demands. After assessing your existing treatment processes, we can recommend improvements to make your treatment plant more effective at removing heavy metal precipitants.
What’s more, we will not only help you meet your discharge consent conditions, we will also help reduce the day to day costs of your effluent treatment.
Effective treatment solutions for heavy metal precipitants
Contact us today to discuss your requirements and book a consultation.