Calcinated meat-bone meal was mineralized in lab. fluidized bed reactor by combustion of liq. petroleum gas at 300-1000 degrees C to produce hydroxyapatite. After mineralization, the hydroxyapatite content in the product was 74%. The sp. surface of the raw material was decreased from 14 m(2)/g down to 3 m(2)/g. The C, H and N contents were decreased by 95%, 42% and 83%, resp. The product exhibited an inhibitory action on the gas combustion.