Either a PD blower (i.e. Roots) or a centrifugal blower can be used in this application.
 
For a PD blower, 300 scfm is required and I'd probably use either 6 or 8 inch diameter pipe to keep the velocity low.  Pet coke is very abrasive so a dense-phase type of system would be best operating in suction mode.  The bin vent filter would need to be 75 square feet of cloth area.  The bin will need to operate under vacuum so it may not be possible to operate under suction.  If so, welded/flanged construction of the piping would be advisable to avoid leaks in a positive pressure system.
 
If you use a centrifugal blower, the solids to air ratio will need to be low and the pipe much larger (12 inches diameter).  The blower would be 1,600 scfm and the bin vent filter would be 400 square feet of cloth area.  A suction system would probably be OK since the pressure drop would be about 6-8 in. w.c.