Harper has extensive experience in processing a variety of materials for the Rare Earths market. As Rare Earth materials become increasingly critical to the global supply chain of many new and emerging technologies, manufacturers must rely on a trusted partner like Harper to help scale up and refine their thermal processing regimes. Our rare earth processing furnaces and kilns have been successful in meeting the exacting demands of this industry while enabling the customer towards greater competitive advantage.
Ideal thermal processing technology solutions for rare earths include Rotary and Pusher systems, which employ indirect firing methods as a superior approach to deliver increased product purity and decreased energy consumption. Process materials come in contact only with controlled gases and a pure metal / ceramic tube. Additionally, the temperature profile of an indirect fired furnace can be more accurately controlled. This yields improvement of product quality, grain size distribution (low micron sized range) and morphology of particles. Dust and particle entrainment of the bed material is also substantially reduced in an indirect fired kiln.
Technology Solutions for Rare Earths

Many applications require performance and safety that is only achieved by maintaining ultra-high purity. Harper’s Rotary systems consider these high purity applications from beginning to end: material in-feed valves and feeder, high-heat reactor tube, product cooling tube, and material discharge valves and collection. We have the experience to engineer these components to achieve a chemically inert environment all while maintaining a gas-tight and dust-tight system for your advanced material.
Learn more about Rotary Furnaces.

As many thermal processes for rare earth metals require exacting conditions, our innovative design enhancements consider the delicate pressure control within the system to provide accurate direction of the atmosphere flow path in the kiln. This facilitates evacuation of volatiles and optimizes atmosphere uniformity. Additionally, Harper’s unique gas curtain technology provides zone-to-zone atmosphere definition under specific conditions.
Learn more about Pusher Furnaces.