Concerning the main burner, a Pillard multichannel should be able to burn anthracite without any problem, so you should do some basic checks:

- ensure you have enough oxygen at kiln inlet (2-3%)

- ensure your anthracite is dried (max 2% moisture) and milled correctly. For milling, the rule of thumb is to aim a residue at 90 µm = half the volatile matter of the coal.

- check your burner: do you have enough axial and radial air (check the pressures on the burner)? Is the burner tip not damaged ?

If you find nothing, you can revert to Pillard for support.

On the calciner, as mentioned by Mr. Wilfred, the RSP is able to produce very high temperature in the combustion chamber. The high temperature of the refractory can then immediately ignite even very difficult fuels. I know several kilns with RSP working entirely with petcoke for example. No oil support should be needed. So, the same kind of checks apply as for the main burner (O2 after calciner, anthracite quality, air repartition on the burner and combustion chamber). Are you also sure it is not just a stupid interlock switching off the coal ?  

Best regards.