Kellogg ammonia processes

COMMERCIAL AMMONIA PROCESSES 7.3.1. The Kellogg Ammonia Process... 

Figure 7. Kellogg s new ruthenium-catalyst based advanced ammonia process combined with the reforming exchange system. (Used with permission of Chemical Engineering.)...

The design sketched above is an elaborate version of the so-called Kellogg Advanced Ammonia Process (KAAP) in which iron-based catalysts are used in the first bed, and ruthenium-based catalysts, which bind nitrogen more weakly, are used in the second, third and fourth beds [T.A. Czuppon, S.A. Knez, R.W. Schneider and G. Woroberts, Ammonia Plant Safety Relat. Pacil. 34 (1994) 236]. 

Alkali-promoted Ru-based catalysts are expected to become the second generation NHs synthesis catalysts [1]. In 1992 the 600 ton/day Ocelot Ammonia Plant started to produce NH3 with promoted Ru catalysts supported on carbon based on the Kellogg Advanced Ammonia Process (KAAP) [2]. The Ru-based catalysts permit milder operating conditions compared with the magnetite-based systems, such as low synthesis pressure (70 -105 bars compared with 150 - 300 bars) and lower synthesis temperatures, while maintaining higher conversion than a conventional system [3]. 

KAAP [Kellogg advanced ammonia process] The first high-pressure process developed for synthesizing ammonia from its elements which does not use an iron-containing catalyst. The reformer gas for this process is provided by the KRES process. The catalyst was developed by BP it contains ruthenium supported on carbon. Developed by MW Kellogg Company in 1990 and first installed by the Ocelot Ammonia Company (now Pacific Ammonia) at Kitimat, British Columbia, from 1991 to 1992. Another plant was installed at Ampro Fertilizers in Donaldsonville, LA, in 1996. 

Kellogg Advanced Ammonia Process (KAAP), 19 621 Kelly leaf filter, 11 365 Kelp, 14 360... 

M. W. Kellogg has developed a new technology in the synthesis of ammonia. They employ a ruthenium on graphite as the catalyst on Kellogg Advanced Ammonia Process (KAAP). The process is the first to employ a non-iron based catalyst and was co-developed with British Petroleum Ventures. The KAAP has been commercialized since 1994, and has been used in an increasing number of projects. 

Kellogg Brown Root Advanced Ammonia Process - Plus (KAAP)... 

The KAAP (Kellogg Advanced Ammonia process) process is the first high-pressure ammonia synthesis process that makes ammonia from nitrogen and hydrogen without the aid of an iron-containing catalyst.1 It is described in References 22-25. 

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. 

Figure 95. Kellogg advanced ammonia process (KAAP) a) Compressor b) PGRU c) Refrigeralion...

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]. 

S. K. Jain, G. A. Moser, and L. K. Rath, "Coal-to-Ammonia Via the Kellogg/KRW Process," AIChE Spring National Meeting New Odeans, La., Apr. 6—10, 1986, American Institute of Chemical Engineers, New York. 

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. 

Figure 6.14. The Kellogg Advanced Ammonia Process (KAAI Synthesis Loop.

Czuppon, T. A., et. al. 1993. The Kellogg Advanced Ammonia Process First Commerlcal Application at Ocelot Ammonia Company, Ammonia Safety Symposium. 

Reaction engineers are expected to transform laboratory discoveries of new synthesis routes or design concepts into economic, safe, and environmentally compatible processes. The highly competitive industrial environment has added the need to shorten the time interval in which this task has to be completed and to decrease the production price. This motivated several innovations. The first was development of novel catalysts, which increased the yield in existing processes, such as the novel Kellogg ammonia-synthesis process, which uses the much more active BP catalyst. Other catalysts were designed to provide either new synthesis routes, such as the production of synthesis gas by direct oxidation, or new products, such as production of novel polymers by metallocene catalysts. 

Since ruthenium catalyst is expensive, highly active and readily inhibited by H2, the process for the ammonia synthesis must be modified to fit these features. In 1980, BP and Kellogg Corporation cooperated to develop a novel ammonia synthesis system, in which BP was to develop a new ammonia synthesis catalyst with high activity at low temperatures and low pressures, while Kellogg was responsible for the development of the matching technology for the process of ammonia synthesis. After a joint effort for 10 years, a process called Kellogg Advanced Ammonia Process (KAAP) was developed successfully (Fig. 1.26). 

KAAP plus An improved version of KAAP, announced by Kellogg Brown Root in 1999. It combines the features of the KBR Advanced Ammonia Process, the KBR Reforming Exchanger System, and the KBR Purifier technology. The catalyst is the same as that used in KAAP. In 2003, more than 200 large-scale plants were operating or had been contracted. 

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