Brenco > Case Studies

Laser clad wear-resistant titanium hardfacing

Challenge

Corrosion and erosion are major challenges in the mining industry’s high pressure acid leaching (HPAL) environment to separate nickel from laterite ores. The process involves mixing crushed ore, water and concentrated acid at elevated temperatures (255° C) and pressures (725 psi) to create a slurry in an autoclave vessel. The slurry is then washed and the nickel recovered. In these conditions, agitator blades are exposed to a combination of high shear, tip speed and temperature, in the effective mixing of abrasive solids, acid and solution. Increasing the service life of these blades will reduce shutdowns and lower production costs.

Solution

Brenco worked with the mining operation to understand the wear characteristics of the agitator assembly. This understanding enabled Brenco to develop a proprietary hardfacing solution—a laser clad titanium—which was put to the test in a 16-month trial campaign.

Results

Campaign 1

In Campaign 1, Brenco applied 3 mm of their proprietary laser cladding to the high wear areas of the agiator blades, and the impeller was installed in an HPAL autoclave compartment. An unplanned shutdown seven months later allowed an inspection of the blades, which were still in good operational condition.

Brenco proprietary laser cladding on impeller
Campaign 1: Brenco proprietary laser cladding (3 mm)

Campaign 1: Seven months after initial installation, Brenco’s blades were still in good operational condition.

Campaign 2

In Campaign 2, as a trial comparison, an impeller with 5 mm PTA-applied Ti-Ox reaction overlay from a competitor was installed in the adjacent compartment of the same autoclave. The Brenco impeller was also put back into service.

Competitor’s Ti-Ox PTA reaction overlay on impeller
Campaign 2: Competitor’s Ti-Ox PTA reaction overlay (5 mm)

Campaign 2: Competitor’s 5 mm thick (Ti-Ox) PTA reaction overlay was tested for nine months in agitation service in high pressure acid leaching mining process.

After nine months of service (of which Brenco’s laser cladding had previously performed seven months of severe service), both impeller blades were re-examined. While the competitor hardfacing showed significant signs of disintegration, Brenco’s proprietary laser clad blades could have easily served another nine months, totaling 25 months of productive service.