Abstract: A catalyst combustor is here disclosed which comprises a catalyst section for permitting the catalyst combustion of a fuel, a burner for preheating the catalyst section, a cross flow type heat exchanger for preheating air for combustion which is disposed in a combustion gas generated by the catalyst combustion, and a fan for feeding the air for combustion to the burner via the cross flow type heat exchanger.

Abstract: Molten pitch is mixed and atomized in an inert gas stream having a temperature less than that of the molten pitch, cooled to the ordinary temperature and separated from the gas stream.Fine powder such as carbon, silica alumina and the like is added to at least one step of the process to improve the fluidity of the thusly obtained fine solid pitch spheres. The pitch spheres are easy to storage, handle and transport as they behave like a fluid.

Abstract: A heavy hydrocarbon feed stock is, after being heat-treated in a first cracking zone, is introduced into a second thermal cracking zone for obtaining a thermally cracked product and a pitch product. The second cracking zone has a plurality of cracking reactors which are connected in series, through which is successively passed the treated feed stock and to each of which is supplied a gaseous heat transfer medium to maintain the liquid phase therein at a temperature sufficient for effecting the thermal cracking and to strip the resulting distillable, cracked components from the liquid phase. The thermal cracking temperature in one reactor is so controlled as to become higher than that in its adjacent upstream-side reactor. The distillable, cracked components in respective reactors are removed overhead therefrom and separated into a heavy fraction and a light fraction, while the liquid phase in the downstream-end reactor is discharged therefrom for recovery as the pitch product.

Abstract: A heavy hydrocarbon feed stock is, after being heat-treated in a first cracking zone, introduced into a second thermal cracking zone for obtaining a thermally cracked product and a pitch product. The second cracking zone has a plurality of cracking reactors which are connected in series, through which is successively passed the treated feed stock and to each of which is supplied a gaseous heat transfer medium to maintain the liquid phase therein at a temperature sufficient for effecting the thermal cracking and to strip the resulting distillable, cracked components from the liquid phase. The thermal cracking temperature in one reactor is so controlled as to become higher than that in its adjacent upstream-side reactor. The distillable, cracked components in respective reactors are removed overhead therefrom and separated into a heavy fraction and a light fraction, while the liquid phase in the downstream-end reactor is discharged therefrom for recovery as the pitch product.