Kellogg ammonia converter

Fig- 28.8, Horizontal ammonia converter, Kellogg design, (Hydrocarbon Processing, pp. iib-izz, uec 1978, copyright 1978 by the Gulf Publishing Company.)... 

As discussed above, several different types of ammonia converters are available. These types include axial quench converters (e.g., standard Kellogg reactors), tube cooled converters (e.g., TVA and Synetix designs), axial-radii designs (e.g., Ammonia Casale retrofit) and Kellogg s horizontal design. Typical operating data for different types of ammonia converters are shown in Table 6.4204. 

After C02 removal, final purification includes methanation (8) gas diying (9) and ciyogenic purification (10). The resulting pure synthesis gas is compressed in a single-case compressor and mixed with a recycle stream (11). The gas mixture is passed to the ammonia converter (12), which is based on the Kellogg Brown Root Advanced Ammonia Process (KAAP). It uses a precious metal-based, high-activity ammonia synthesis catalyst to allow for high conversion at the relatively low pressure of 90 bar. 

The M. W. Kellogg ammonia converter retrofit, Kellogg company brochure HG/2.5M/3-88 (1988)... 

Ammonia Converter Design - Today all low-energy designs use indirectly cooled converters. The design and layout offered by various ammonia plant designers differ considerably. Kellogg s Horizontal Converter and Topsoe s Series 200 Converter use two catalyst layers with an intermediate heat exchanger for... 

Figure 7.7. Kellogg ammonia converter. Courtesy of British Sulphur Corporation.

Fig. 17. (a) Kellogg vertical quench converter (b) Ammonia Casale converter basket modification. 

For revamps of ammonia synthesis converters, Ammonia Casale offers 1) an in-situ modification of bottle-shaped converters of the Kellogg type, and 2) a three-bed intercooled configuration. The intercooled design is similar in some ways to the Uhde design discussed below213. 

Description The key features of the Kellogg Brown Root (KBR) Purifier process are mild primary reforming, secondary reforming with excess air, cryogenic purification of syngas, and synthesis of ammonia over magnetite catalyst in a horizontal converter. Desulfurized feed is reacted with steam in the primary reformer... 

Kellogg Brown Root Ammonia Natural gas, LPG, naphtha Synthesis in B RB adiabatic converters/mild reforming with gas turbine, cryogenic purifier 26 1997... 

Kellogg has developed for its ruthenium catalyst based KAAP ammonia process [404], [478] a special converter design. Four radial flow beds are accommodated in a single pressure shell with intermediate heat exchangers after the first, second and third bed. The first bed is loaded with conventional iron catalyst, the following ones with the new ruthenium catalyst. Figure 95 is a simplified sketch of the converter and the synthesis loop of the KAAP for a new plant. For revamps Kellogg has also proposed a two-bed version completely loaded with ruthenium catalyst to be placed downstream of a conventional converter [398]. 

Figure 17.21. Some recent designs of ammonia synthesis converters, (a) Principle of the autothermal ammonia synthesis reactor. Flow is downwards along the wall to keep it cool, up through tubes imbedded in the catalyst, down through the catalyst, through the effluent-influent exchanger and out. (b) Radial flow converter with capacities to l tons/day Haldor Topsoe Co., Hellerup, Denmark), (c) Horizontal three-bed converter and detail of the catalyst cartridge. Without the exchanger the dimensions are 8 x 85 ft, pressure 170 atm, capacity to 2000 tons/day (Pullman Kellogg), (d) Vessel sketch, typical temperature profile and typical data of the ICI quench-type converter. The process gas follows a path like that of part (a) of this figure. Quench is supplied at two points (Imperial Chemical Industries).

Alternatively, KBR offer the KAAP (Kellogg Advanced Ammonia Process) synthesis concept, where the synthesis gas is converted to ammonia in a low pressure synthesis loop (8-9 MPa) featuring a four bed synthesis converter loaded with conventional iron based catalyst in the first bed and Ru-based catalyst in the lower beds. This technology has so far only had limited use due to the high cost of Ru. 

It is well known that the conversion of hydrogen and nitrogen per pass is only 20%-30% for the present catalytic ammonia synthesis technology (Table 1.4). Most synthesis gases need to be returned to the reaction system, which increases power consumption. In order to increase conversion per pass, it must increase the outlet ammonia concentration of reactor. Accordingly, it can be seen from Table 1.4 that it is necessary to increase reaction pressure for small and medimn scale aimnonia plants and Topspe process, or to reduce the content of inert gas in sjmthesis gas for Topspe and Braun processes, or to reduce ammonia concentration in the inlet of converter for small and medium scale ammonia plants and Kellogg process. But all of these operations will add the power consumption or unit gas consumption. 

Converter for an ammonia synthesis process comprising two-part vertical cylindrical pressure shell with three annular catalyst beds and two axial heat exchangers. S. A. Noe (M. W. Kellogg Co.). EP 2533350 (1988). 

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