I might add my atavar shows an early model of my 'waste vegetable oil' burner, running on test at night to get a good flame pic [ and deemed unsuitable due to unburned oil in the flame lacquering the boiler innards!] The 'flame retention head' is just visible, glowing dull red hot. This is about 100,000 BTU / 30kW power, based on Danfoss parts.

I'm currently able to get a blue 40kw flame from WVO by thermally cracking the oil at 700F before the burner head, unit mothballed till the spring as other projects have taken priority, like 'her indoors' insisting on a kitchen! I'll post more then.

Alan

Wood work but can't!