Exchanger reformer

Petrochemical Heat Exchangers Reformer tubing Water and Gas supply piping Pipelines... 

Ammonia Plant 1. Where possible, use natural gas as the feedstock for the ammonia plant, to minimize air emissions. 2. Use hot process gas from the secondary reformer to heat the primary reformer tubes (the exchanger-reformer concept), thus reducing the need for natural gas. 

Heat exchange autothermal reforming, with a process gas heated steam reformer (heat exchange reformer) and a separate secondary reformer, or in a combined autothermal reformer, using excess or enriched air (under-stoichiometric or stoichiometric H/N ratio)... 

Description Syngas preparation section. The feedstock is first preheated and sulfur compounds are removed in a desulfurizer (1). Steam is added, and the feedstock-steam mixture is preheated again. A part of the feed is reformed adiabatically in pre-reformer (2). The half of feedstock-steam mixture is distributed into catalyst tubes of the steam reformer (3) and the rest is sent to TEC s proprietary heat exchanger reformer, "TAF-X" (4), installed in parallel with (3) as the primary reforming. The heat required for TAF-X is supplied by the effluent stream of secondary reformer (5). Depending on plant capacity, the TAF-X (4) and/or the secondary reformer (5) can be eliminated. 

CXR [Compact exchange Reforming] A process for converting natural gas into syngas. Developed from 1996 jointly by Methanex, Synetix and ABB Lummus Global, but subsequently abandoned. 

Synetix Methanol (LCM) Natural gas, refinery offgas Heat-exchange reforming and low-pressure loop technology give high efficiencies 1 1996... 

Today contractors and licensors use sophisticated computerized mathematical models which take into account the many variables involved in the physical, chemical, geometrical and mechanical properties of the system. ICI, for example, was one of the first to develop a very versatile and effective model of the primary reformer. The program REFORM [361], [430], [439] can simulate all major types of reformers (see below) top-fired, side-fired, terraced-wall, concentric round configurations, the exchanger reformers (GHR, for example), and so on. The program is based on reaction kinetics, correlations with experimental heat transfer data, pressure drop functions, advanced furnace calculation methods, and a kinetic model of carbon formation [419],... 

A more recent development that breaks away from the usual plant configuration is to replace the traditional fired primary reformer with an exchanger reformer which uses the heat of the effluent of the secondary reformer [471]-[478], [1036], [1037]. Also other applications have been reported in which flue gas [1038] heat from the fired reformer is used to perform a part of the reforming. 

Processes without a fired primary reformer (exchanger reformer)... 

Montedison Low-Pressure Process. The Montedison low-pressure process [940], [1036], [1128], [1129] involves a split flow to two primary reformers. About 65% of the feed-steam mixture flows conventionally through the radiant tubes of a fired primary reformer followed by a secondary reformer. The balance of the feed-steam mixture passes through the tubes of a vertical exchanger reformer. This exchanger reformer has a tube sheet for the catalyst tubes at the mixed feed inlet. There is no tube sheet at the bottom of the tubes, where the reformed gas mixes directly with the secondary reformer effluent. The combined streams flow on the shell side to heat the reformer tubes in a manner similar to that described for the M. W. Kellogg KRES reformer, see Sections 4.1.1.8 and 5.1.4.3). The process air flow is stoichiometric. Synthesis is performed at 60 bar in a proprietary three-bed indirectly cooled converter with am-... 

Processes without a Fired Reformer (Exchanger Reformer)... 

Chiyoda Process [1137], In this process the traditional fired primary reformer is also replaced by an exchanger reformer and the heat balance requires excess air in the secondary reformer with the consequence of a cryogenic unit as final step in the makeup gas preparation to remove the surplus of nitrogen. Additionally, gas turbines are proposed as drivers for the process air compressor and synthesis gas compressor with the hot exhaust being used for steam generation and feed gas preheating. 

Another type of steam-reforming reactor that is attracting increasing attention is known as gas heated reformers or heat exchange reformers. In such reformers, heat is transferred by convection and the heat source is a hot process gas from another reformer or a partial oxidation reactor. A number of different installations of heat exchange reformers can be envisaged. In Fig. 5, the installation of a heat exchange reformer either in series or in parallel to an auto-thermal reformer (ATR) is illustrated. 

Fig. 5 Series and parallel arrangement of heat exchange reformers with ATR as the main reformer. (From Ref.. ) this...

In heat exchange reformers, special precautions must be taken to avoid corrosion. In such reformers the metal temperature is often high enough for metal dusting to occur and low enough for thermodynamic potential to exist. Special alloys or other techniques are needed to prevent metal dusting in these cases. This area is the subject of considerable research to widen the limits of operation to more severe operating conditions. 

Finally, progress in the heat-exchanger reforming (LCA) process and new developments in electrically driven compressors may make small-scale (300 tpd-400 tpd) installations economically feasible. 

Miyasugi, T., et al. 1984. Energy-Sa mg Ammonia Process with Heat Exchanger Reformer, Am-... 

---