THERMAL DECOMPOSITION TUBE

• Main Author: HASHIMOTO, KUNIHIDE
• Format: Patent
• Language: English; French; German
• Published: 10.12.2014
• Subjects: BLASTING; CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; CRACKING HYDROCARBON OILS; DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OFGENERAL APPLICATION; FUELS; HEAT EXCHANGE IN GENERAL; HEATING; LIGHTING; LUBRICANTS; MECHANICAL ENGINEERING; METALLURGY; MINERAL WAXES; PEAT; PERFORMING OPERATIONS; PETROLEUM, GAS OR COKE INDUSTRIES; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVEHYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, ORGASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; TECHNICAL GASES CONTAINING CARBON MONOXIDE; THEIR RELEVANT APPARATUS; TRANSPORTING; WEAPONS

A thermal cracking tube is provided which is adapted to suppress pressure losses to the greatest possible extent while maintaining a heat transfer promoting effect on the fluid inside the tube. The tube passes a fluid therethrough from one end thereof toward the other end and has a plurality of rows of projections extending circumferentially along an inner surface of the tube orthogonal to or as inclined with respect to the axis of tube, each of the projection rows including a plurality of projections provided on the tube inner surface. The tube is defined by S/10ÀD=0.2-0.7, h/D=0.02-0.05 and L/nD=0.04-0.5 wherein D is the inside diameter of the tube, h is the height of an optional projection A included in a projection row ±, L is the length of circular arc of the projection A in a direction orthogonal to the tube axis, and S is the area of a region R surrounded by the projection A, phantom lines L1 and L2 extending respectively from circumferentially opposite ends of the projection A in parallel to the tube axis and a projection row ² downstream from the projection row ±.