Abstract: A method of burning a combustible solid residue from a chemical plant, which comprises feeding a slurry of combustible solid residues in an oil, the amount of the oil being at least 0.5 part by weight per part by weight of the combustible solid residues, into a burner in a combustion furnace comprised of a main combustion chamber having the burner in its arch, a secondary combustion chamber formed in the lower portion of the main combustion chamber, and a flue gas duct provided beneath and following the secondary combustion chamber, burning the residue in the main combustion chamber, conducting the combustion gas into the secondary combustion chamber, and allowing it to reside at a temperature 800.degree. to 1000.degree. C. for at least 0.5 second.

Abstract: A cracking furnace for thermal cracking of hydrocarbon feedstocks has a central burner provided vertically at the center of the ceiling of a combustion chamber, side burners provided vertically at both sides of the central burner, and reaction tubes vertically arranged between the central burner and resepctive side burners. The reaction tubes are arranged in rows along the longitudinal direction of the chamber and form arch bands at the lower part of the combustion chamber. A combustion gas-inducting duct is provided at the bottom of the chamber, a quenching heat exchanger is provided at the upper part of the chamber, and a reaction tube exit header is provided for connecting a plurality of exits of the reaction tubes to the quenching heat exchanger.

Abstract: Arrangement of heat transfer tubes in a heating furnace in which the heat transfer tube is divided into several paths in the radiant heat transfer zone and these branched tubes are arranged in juxtaposition and alternative relation in each row and divided into a plurality of groups in a cycle of the alternation, and burners are provided in front of each tube group.

Abstract: Vertical tube type cracking furnace in which a convection-heating section for preheating the process fluid is provided above the combustion chamber, and gas passages connecting the convection-heating section and the combustion chamber are symmetrically provided.