Pyrolysium with conventional heat sources.
The current practice in cremation is that the coffin with the corpse is placed in a cremation-furnace and is burned till only ashes remain. After that the tray is removed ash pulverized and metal parts removed, the ash is then placed in an urn. Due to turbulence and air movements in the furnace, filters are in place to prevent exhaust of material in the environment.
With pyrolysis this will change, the corpse is placed in an reusable steel chamber. In an two stage process, where in the first stage in a moderate temperature most of the water content of the corpse is evaporated. In the second stage the pyrolysis chamber is placed in high temperature zone where the pyrolysis take place. The process is not energy specific, meaning that it can utilize any heat source that is available as long as it has the right temperature. (400-600 degrees celsius)
It is foreseeable that, thanks to the fact that the corpses are in their own chambers, multiple pyrolysis processes share the same heat source improving the efficiency of the overall process.
Or that the first stage uses the heat resulting from the second stage.