CCR Refinery, a Glencore company, and industry leader in copper refining and precious metals processing, had a problem. As part of the copper refining process, copper anodes are immersed in a 15% sulfuric acid solution. Through an electrolytic process, 99.9% pure copper cathodes are created. This process also leaves behind a waste solution with valuable metals, and so a second process is engaged to reclaim those metals.
This waste solution is moved to an Evaporator unit. In the Evaporator, hot air is pumped into the solution. This raises the strength of the sulfuric acid solution to 70% and causes nickel sulfate to precipitate out of solution. The chemical reaction also creates a highly corrosive steam at 300°F that needs to be vented. And here’s where the problem occurs.
The lining of the elbow pipe that vented this sulfuric acid steam could not long survive the acid mist’s corrosive effects.
Figure 1 — Evaporator Tank to Process Sulfuric Acid WasteAlso, the high temperatures, extreme temperature fluctuations and vacuum pressures all contributed to the creation of cracks, pinholes and leaks in the lining of the pipe.
This meant that CCR had to shut down one of these two production lines every two to three months to repair the PFA lining. The repair costs and the lost productivity were a growing problem.
CCR had it in mind to try an exotic metal alloy tank but, while it could handle the temperatures and did not use a liner, it would not handle the corrosive effects of the sulfuric acid steam. CCR even considered converting back to antiquated lead and brick-lined equipment, but they couldn’t solve the weight-bearing needs of the elbow.
So, Mario Dalcourt, one of CCR’s maintenance mechanical engineers, and his team reached out to the European maker of the Evaporator to ask what they might suggest to combat the issue. Fortunately, they had deployed a new PFA technology that worked very well. Once CCR understood the capabilities of this new PFA lining approach, they knew a cost-effective solution was at hand.
Now, CCR just needed to find a company knowledgeable in this new PFA technique that was closer to their facility in Montreal. After a bit of internet research, they connected with Pennsylvania-based Electro Chemical Manufacturing, a world leader in the fabrication, welding and installation of fluoropolymer linings.
Elbow Pipe to Vent Sulfuric Acid MistAfter a plant visit to Electro Chemical Manufacturing (ECM) and a series of in-depth conversations with their experienced PFA lining specialists, Mario and his team knew that Electro Chemical Manufacturing had the technical knowledge, plastic welding know-how and installation experience CCR was looking for in their new provider.
Electro Chemical Manufacturing also had one more big “plus” – they had a new high-temp epoxy they created in tandem with a major US engineering university. This new adhesive combined the high-temperature tolerance of an epoxy with the elasticity of an elastomeric adhesive. ECM’s new proprietary adhesive could tolerate temperatures up to 360° F without becoming brittle and cracking.
CCR gave Electro Chemical Manufacturing the contract to re-line their elbow pipe. In November 2016, the new pipe came on line. And after one year of operation, CCR has not had to do any maintenance to it!
The CCR team is thrilled with the performance of the new PFA lining. Not having to shut down for service four to six times a year has meant notable savings in repair costs as well as a boost in productivity.
“Electro Chemical Manufacturing’s PFA lining solution has already more than paid for itself in terms of saved maintenance costs and less downtime!”
– Mario Dalcourt
Maintenance Mechanical Engineer, CCR
The team at CCR believes their elbow pipe will keep going for quite some time. Not only are they saving on repairs and downtime, but also their new PFA lining has reduced their concerns about any potential environmental exposure in the workplace.
If you’d like to learn about our proprietary and revolutionary new adhesive, contact Knight Materials here.
Project Details
End customer: CCR Refinery (a Glencore company), Montreal, Canada
Fabricator: Electro Chemical Manufacturing, Pennsylvania, USA
Material: PFA GGS 2.3 mm fabric backed sheets | AGRU
Medium: Sulfuric acid solution vapor (70 %)
Temperature: 150 °C
