Elliott pioneered power recovery expander turbine technology in the 1950's and has been a leader in the field ever since. An Elliott TH power recovery expander turbine converts high temperature, low pressure flue gas energy into usable power. The turbine often is used to drive compressors or generators in refinery fluid catalytic-cracking (FCC) service. Recovery power for these applications can approach 50,000 hp (37,300 kW).

Elliott design engineers continue to advance expander technology to meet the changing demands of the FCC process. By using computational fluid dynamics to verify flow path design and minimize blade erosion, we have significantly extended typical time between turnarounds far beyond the industry average, without sacrificing efficiency. A number of Elliott expanders have exceeded 9 years of rated service without a blade change. To insure reliability, we design all critical components using finite element analysis. And we are continuously developing new coatings and materials to resist the erosive and corrosive environment of the FCC process.

Elliott power recovery expanders are the most dependable and durable designs in the industry.

Leadership in design and reliability

Power recovery expanders pose unique challenges. The extremely high temperatures, large volumes of gas, and the continuous flow of very hard and potentially erosive catalyst particles entrained in the gas stream require special design considerations. Elliott has developed new alloys and metallurgical treatments that result in superior reliability and availability, typically equivalent to other equipment in less arduous services in the FCC process. Elliott expanders routinely operate for as long as 9 years or more with a single rotor assembly. Elliott recently overhauled a unit that had operated reliably and efficiently for ten years with the same blades.