Semi-regenerative reforming

Le Goff, P. Pike, M. Increasing semi-regenerative reformer performance through catalytic solutions. Presented at the 3rd European Catalyst Technology Conference, Euro Petroleum Consultants (EPC) Amsterdam, Feb 2002. 

Semi-Regenerative reforming is carried out in cycles, with the following components ... 

Ancheyta, J., Vhlafuerte, E., Schacht, R, Aguhar, R., Gonzilez, E. 2002. Simulation of a semi-regenerative reforming plant nsing feedstocks with and withont benzene precnrsors. Chem. Eng. Tecnol. 25 541—546. 

Aside from the above reforming reactions, a small amount of feed components are converted to polymeric hydrogen deficient products which deposit on the catalyst as "coke." A coke buildup results in activity and selectivity loss which ultimately requires catalyst regeneration. In semi-regenerative operation, the coking rate is maintained at a low level to provide cycles of at least three to six months. In cyclic units, coking conditions are inherently much more severe so that frequent regenerations are required. 

Powerforming is a version of the platinum reforming process. Basically there are two types of unit semi-regenerative and cyclic. The choice of unit and the exact process conditions used will depend to a large extent on the particular application. However, certain generalizations regarding each of the two types can be made. 

Mudt, D. R. Hoffman, T. W. Hendon S. R. "The Closed-Loop Optimization of a Semi-Regenerative Catalytic Reforming Process" Paper Presented at the National AIChE Meeting, Houston, Texas (March 1995). 

In the reformer, multiple reactions occur simultaneously. This process is endothermic and is subject to carbon laydown thus, refiners must regenerate reforming catalysts. Several catalyst-regenerating approaches are possible. Semi-regenerative processes use... 

Hydroprocessing extensive use of extrudates and occasionally of spheres Reforming use of extrudates (semi-regenerative units) and spheres (CCR types of units)... 

Depending on the type of regeneration (coke bum-off), reforming processes are classified into three types (i) semi-regenerative, (ii) cychc regenerative, and (iii) continuously regenerative. 

In 1992, 74% of the commercial reforming plants operating in the USA, Japan, and Europe were semi-regenerative, 11% cyclic, and 15% continuous (Farrauto and Bartholomew, 1997). 

After choosing a representative kinetic model, we must decide how to represent the remaining units for a truly integrated model. Researchers have applied many of the kinetic networks described in the previous section in integrated process models. Figure 5.8 is an overview the key features of an integrated process model for a three-section reformer. This overview applies to both semi-regenerative fixed bed and CCR reformers. 

Semi-regenerative naphtha reformer feed effluent exchangers, where reduced pressure drop brings additional benefits, increasing hydrogen recycle ratio without changes to recycle gas compressor... 

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