Coperion recently supplied and commissioned a wear-protected rotary valve for the RWE Power AG Ville/Berrenrath coal refinery. The rotary valve type ZXQ with a diameter of 600mm feeds dry lignite into a pneumatic conveying system that transports the material from a new vertical roll mill to the storage silos. The conveying pressure of the system ranges from 0.9 to 1.1 bar. The rotary valve is designed for a capacity of 60t/h; however, a peak performance of approximately 80t/h has already been recorded. In another RWE coal refinery, a rotary valve of the same design achieved conveying capacities up to100t/h.
This powerful rotary valve includes highly effective wear protection that safeguards the long-term performance of the product. In addition, the gap and leakage gas flow rates are reliably calculated and guaranteed even when temperatures fluctuate. Lastly, an optimal geometric design is provided to achieve the high filling and emptying levels required by the user for “light” bulk materials that may fluidize with a fluctuating conveying pressure. Coperion uses the Finite Element Method to determine the correct specifications for the rotary valve. Coperion test labs also provide data analysis for pneumatic conveying and gas leakage measurements.