A system for preheating a pressure vessel includes a throat including an area of excess heat and a dome having an area of deficient heat. The throat includes a conduit extending from a pressure vessel opening to the pressure vessel interior. A plenum is defined between the throat and a seal within the dome. The throat extends from the dome toward a dome floor. The floor is substantially perpendicular to the throat. A conduit is coupled to the plenum and channels a flow of purge fluid into the plenum wherein heat from the throat is transferred to the flow of purge fluid and carried by the flow of purge fluid into the area of deficient heat via a gap defined between the seal and the floor such that the flow of purge fluid reduces temperature differential stresses within the pressure vessel and purges the area of deficient heat.

A syngas loop boiler includes a casing that surrounds a tube bundle, wherein the tube bundle includes a plurality of tubes. One end of each of the tubes is joined to a tube-sheet provided with corresponding tube-sheet inlet holes for inletting the syngas in the boiler, wherein each tube-sheet inlet hole is internally provided with at least a protective sleeve welded at both ends to corresponding surfaces of the tube-sheet inlet hole. Each tube-sheet inlet hole is provided with a first respective weld overlay placed at the inlet mouth of the tube-sheet inlet hole, so that a first end of each protective sleeve is welded to the first weld overlay. Each tube-sheet inlet hole is internally provided with at least a bore groove that contains a respective in-bore second weld overlay, so that the second end of the protective sleeve is welded to the in-bore second weld overlay. Each protective sleeve is thus welded at both ends to respective weld overlays, with the possibility of removal and re-installation without performing any post weld heat treatment.

An anti-fouling composition has been developed that provides an advantageous reduction in the fouling of a structural part in a petroleum-refining system including reducing coking reactions and inhibiting deposition of solids in equipment and lines used for crude oil production and processing. The anti-fouling compositions contain a resin comprising an alkyl phenol-aldehyde resin, a polyolefin comprising a polyalkylene ester, polyolefin amide alkeneamine, polyethylene polyamine, polyalkyleneimine, or a combination thereof; and optionally, a polyalkylene imide, an amine-substituted polyalkylene imide, or a combination thereof; and optionally, N,N′-disalicylidene-1,2-propanediamine.

The invention relates to a pipe for thermal cracking of hydrocarbons in the presence of steam, in which the feed mixture is guided through externally heated pipes, wherein the pipe extends along a longitudinal axis and has a number N.sub.T of grooves that have been introduced into the inner surface of the pipe and extend in a helix around the longitudinal axis along the inner surface, the inner surface into which the grooves have been introduced, in a cross section at right angles to the longitudinal axis, has a diameter Di and a radius r.sub.1=Di/2, the grooves in the cross section at right angles to the longitudinal axis, in their groove base, each have the form of a circular arc and the circular arc has a radius r.sub.2, and
the grooves each have a groove depth TT which, in the cross section at right angles to the longitudinal axis, corresponds in each case to the smallest distance between the circle having the diameter Di on which the inner surface lies and the center of which lies on the longitudinal axis, and the furthest removed point of the groove base of the grooves from the longitudinal axis.

Aspects of the present invention relate to a shell-and-tube heat exchanger (101), a method of using said heat exchanger, and to a hydrocarbon cracking furnace system comprising said heat exchanger. The shell-and-tube heat exchanger comprises at least: a spiral baffle (7) arranged to provide a helical flow path through the shell body (103) and an outlet collector pipe (4) that supports the spiral baffle and that extends substantially coaxially within the shell body, wherein the outlet collector pipe is mounted to and passes through a second tubesheet (106) bordering the shell body (103) on one terminal end, and wherein the outlet collector pipe (4) is separated from a first tubesheet (105) on the opposing terminal end by a gap that allows a shell-side fluid (F2) to exit the shell body (103).

Embodiments described herein relate to a heat exchanger for abating compounds produced in semiconductor processes. When hot effluent flows into the heat exchanger, a coolant can be flowed to walls of a fluid heat exchanging surface within the heat exchanger. The heat exchanging surface can include a plurality of channel regions which creates a multi stage cross flow path for the hot effluent to flow down the heat exchanger. This flow path forces the hot effluent to hit the cold walls of the fluid heat exchanging surface, significantly cooling the effluent and preventing it from flowing directly into the vacuum pumps and causing heat damage. Embodiments described herein also relate to methods of forming a heat exchanger. The heat exchanger can be created by sequentially depositing layers of thermally conductive material on surfaces using 3-D printing, creating a much smaller footprint and reducing costs.

The present discloses a gas-gas high-temperature heat exchanger, including a shell (12), a tube sheet (5), a low-temperature gas inlet pipeline (6) and an outlet pipeline (7), and a high temperature gas outlet (8), the tube is divided into a first heat transfer zone (1) and a second heat transfer zone (2), a low temperature gas (4) flows in the tube, the tube includes a insert component (9) and an outer fin (10); a heat transfer tube in the second heat transfer zone (2) has a sleeve structure, a high-temperature gas (3) flows in the core tube (13), the low temperature gas (4) flows in an annular region between the core tube (13) and an outer tube (14), the high-temperature gas (3) flows out of the core tube (13) and flows into the shell-side area of the second heat transfer zone (2) again.

A heat exchanger for abating compounds produced in semiconductor processes. When hot effluent flows into the heat exchanger, a coolant can be flowed to walls of a fluid heat exchanging surface within the heat exchanger. The heat exchanging surface can include a plurality of channel regions which creates a multi stage cross flow path for the hot effluent to flow down the heat exchanger. This flow path forces the hot effluent to hit the cold walls of the fluid heat exchanging surface, significantly cooling the effluent and preventing it from flowing directly into the vacuum pumps and causing heat damage. Embodiments described herein also relate to methods of forming a heat exchanger. The heat exchanger can be created by sequentially depositing layers of thermally conductive material on surfaces using 3-D printing, creating a much smaller footprint and reducing costs.

Certain implementations of natural gas liquid fractionation plant waste heat conversion to simultaneous cooling capacity and potable water using Kalina Cycle and modified multi-effect distillation system can be implemented as a system. The system includes first waste heat recovery heat exchanger configured to heat a first buffer fluid stream by exchange with a first heat source in a natural gas liquid fractionation plant. The system includes a water desalination system comprising a first train of one or more desalination heat exchangers configured to heat saline by exchange with the heated first buffer fluid stream to generate fresh water and brine.

Certain aspects of natural gas liquid fractionation plant waste heat conversion to simultaneous power and cooling capacities using modified Goswami system can be implemented as a system. The system includes a waste heat recovery heat exchanger configured to heat a buffer fluid stream by exchange with a heat source in a natural gas liquid fractionation plant. The system includes a modified Goswami cycle energy conversion system including one or more first energy conversion system heat exchangers configured to heat a working fluid by exchange with the heated buffer fluid stream, a separator configured to receive the heated working fluid and to output a vapor stream of the working fluid and the liquid stream of the working fluid, a turbine and a generator, wherein the turbine and generator are configured to generate power by expansion of a first portion of the vapor stream of the working fluid, and a cooling subsystem including a cooling element configured to cool a process fluid stream from the natural gas liquid fractionation plant by exchange with a condensed second portion of the vapor stream of the working fluid.