Since 1978...
Fox eductors have been used to inject sorbents into fluidized bed boilers to capture SOx, creating synthetic gypsum or other byproducts that fall out the bottom of the fluid bed boilers.

With pressures in the bed up to 2 to 3 psig, using rotary airlocks against this high backpressure almost certainly creates a blowback, fugitive dust, and eventually an airlock failure/reliability problem.

Fox eductors have been used with many, many different types of sorbents, including hydrated lime - a notoriously difficult material to handle and convey.

Conveying Hydrated Lime
w/ Fox Eductors.
Although by no means perfect in this application, Fox eductors have proven to be an excellent solution to a very difficult problem. Most customers procure two stainless eductors, keeping one in an acid bath or furnace to dissolve or bake off the inevitable build-up within the eductor when conveying hydrated lime.

Request Additional Technical Information:
Case Study #52 - Convey Hydrated Lime in FGD

This schematic shows a typical Fox additive injection system, with a small Rotron blower running at 2–3 psig driving an eductor.

Two 2" Fox eductors convey limestone into a fluidized bed boiler. The airlocks originally supplied with the plant were replaced after numerous maintenance problems.