A system for producing chemicals, such as, ethylene or gasoline, at high temperature (above 1100 degrees C.) having a feedstock source. The system includes a chemical conversion portion connected with the feedstock source to receive feedstock and convert the feedstock to ethylene or gasoline. The conversion portion includes a coil array and a furnace that heats the feedstock to temperatures in excess of 1100 C. or 1200 C. or even 1250 C. or even 1300 C. or even 1400 C. A method for producing chemicals, such as ethylene or gasoline, at high temperature.

A system for producing chemicals, such as, ethylene or gasoline, at high temperature (above 1100 degrees C.) having a feedstock source. The system includes a chemical conversion portion connected with the feedstock source to receive feedstock and convert the feedstock to ethylene or gasoline. The conversion portion includes a coil array and a furnace that heats the feedstock to temperatures in excess of 1100 C. or 1200 C. or even 1250 C. or even 1300 C. or even 1400 C. A method for producing chemicals, such as ethylene or gasoline, at high temperature.

An assembly including a ceramic body. The assembly comprises a tungsten coupling attached to the ceramic body with a first joint that forms a first helium tight seal between the ceramic body and the tungsten coupling and where the first helium tight seal maintains its integrity at a temperature over 400 C. The assembly includes a metal body attached to the tungsten coupling with a second joint that forms a second helium tight seal between the metal body and the tungsten coupling and where the second helium tight seal maintains its integrity at a temperature over 400 C. A method. A mixture. A coupling.

In chemical processes for cracking hydrocarbons, reactors are subject to coking. This results in carburization of the metal substrate for the reactor leading to a reduced reactor life. If the reactor is subject to a decoke process, followed by a steam scour and nitriding there is a reduced tendency to carburization of the metal substrate improving the reactor life.

An anti-coking surface having a thickness up to 15 microns comprising from 15 to 50 wt. % of MnCr.sub.2O.sub.4; from 15 to 25 wt. % of Cr.sub.0.23Mn.sub.0.08Ni.sub.0.69, from 10 to 30 wt. % of Cr.sub.1.3Fe.sub.0.7O.sub.3, from 12 to 20 wt. % of Cr.sub.2O.sub.3, from 4 to 20 wt. % of CuFe.sub.5O.sub.8, and less than 5 wt. % of one or more compounds chosen from FeO(OH), Cr+3O(OH), CrMn, Si and SO.sub.2 (either as silicon oxide or quartz) and less than 0.5 wt. % of aluminum in any form provided that the sum of the components is 100 wt. % is provided on steel.

The present invention relates to the field of fluid heat transfer, and discloses a heat transfer enhancement pipe as well as a cracking furnace and an atmospheric and vacuum heating furnace including the same. The heat transfer enhancement pipe (1) includes a pipe body (10) of tubular shape having an inlet (100) for entering of a fluid and an outlet (101) for said fluid to flow out; internal wall of the pipe body (10) is provided with a fin (11) protruding towards interior of the pipe body (10), wherein the fin (11) has one or more fin sections extending spirally in the axial direction of the pipe body (10), and each fin section has a first end surface facing the inlet (100) and a second end surface facing the outlet (101), at least one of the first end surface and the second end surface of at least one of the rib sections is formed as a transition surface along spirally extending direction. The heat transfer enhancement pipe can reduce thermal stress of itself, thereby increasing service life of the heat transfer enhancement pipe.

The present invention provides low profile, thick (stubby) longitudinal fins having a cross section which is a parallelogram, trapezoid or a triangle extending from 10% to 100% of a coil pass and comprising from 3 to 45 weight % of a coil in a radiant section of a furnace for thermally cracking one or more of paraffins and naphtha. The fins provide an additional surface through which heat may be transferred to the coil making the coil more efficient reducing greenhouse emissions.

The present invention provides low profile, thick (stuby) longitudinal fins having a cross section which is a parallelogram, trapezoid or a triangle extending from 10% to 100% of a coil pass and comprising from 3 to 45 weight % of a coil in a radiant section of a furnace for thermally cracking one or more of paraffins and naphtha. The fins provide an additional surface through which heat may be transferred to the coil making the coil more efficient reducing greenhouse emissions.

In an embodiment of the invention, furnace tubes for cracking hydrocarbons having a longitudinal array of pins having i) a maximum height from 0.5-1.3 cm; ii) a contact surface with the tube, having an area from 0.1%-10% of the tube external surface area iii) a uniform cross section along the length of the pin. (i.e. they are not tapered); and iv) a length to diameter ratio from 1.5:1 to 0.5:1 have an improved heat transfer over bare fins and reduced stress relative to a fined tube.

Some embodiments of the present invention provide components for a serpentine fluid reactor which is optimized for one or more objective functions of interest such as pressure drop, erosion rate, fouling, coke deposition and operating costs. The components are designed by computer modeling the components individually and collectively in which the cross section of flow path is substantially circular under industrial conditions to validate the model design and its operation. Then iteratively the component designs are deformed and the operation of the deformed part(s) is modeled and compared to values obtained with other deformed models until the value of the objective function is optimized (e.g. at an extreme) or the change in the objective function is approaching zero.