Desulfurization calcined coke

Holding times are at constant temperature after calcination. Percent desulfurization is relative to sulfur content in calcined coke. 

Table II. Comparison of Physical Properties of Desulfurized Cokes with Typical Calcined Coke Specifications...

Rcis, T., To coke, desulfurize, and calcine, Hydrocarbon Processing, 1975,... 

SULF-X [Sulfur extraction] A regenerable flue-gas desulfurization process in which the sulfur dioxide is absorbed by aqueous sodium sulfide in a bed packed with pyrite. Ferrous sulfate is produced this is removed by centrifugation and calcined with coke and fresh pyrite. Sulfur vapor is evolved and condensed, and the residue is re-used in the scrubber. Piloted in the mid-1980s. Not to be confused with Sulfex or Sulph-X. 

The experimental work has been conducted in horizontal furnace tube reactors containing fixed beds of sized (1/2 inch x 4 mesh) coke electrically heated and controlled at precise temperatures over the entire bed length. The coke is first calcined, following a temperature profile similar to that of commercial calcining. The calcining is immediately followed by desulfurization with pure or dilute sulfur gases metered from cylinders. 

Figure 2. Desulfurization of Calcined Petroleum Coke as a Function of Time at Temperature.

---