Catalytic reforming unit

For example, in the case of light Arabian crude (Table 8.16), the sulfur content of the heavy gasoline, a potential feedstock for a catalytic reforming unit, is of 0.036 weight per cent while the maximum permissible sulfur content for maintaining catalyst service life is 1 ppm. It is therefore necessary to plan for a desulfurization pretreatment unit. Likewise, the sulfur content of the gas oil cut is 1.39% while the finished diesel motor fuel specification has been set for a maximum limit of 0.2% and 0.05% in 1996 (French specifications). 

The primary sources of toluene and xylenes are reformates from catalytic reforming units, gasoline from catcracking, and pyrolysis gasoline from steam reforming of naphtha and gas oils. As mentioned earlier, solvent extraction is used to separate these aromatics from the reformate mixture. 

Selecting the naphtha type can be an important processing procedure. For example, a paraffinic-base naphtha is a better feedstock for steam cracking units because paraffins are cracked at relatively lower temperatures than cycloparaffins. Alternately, a naphtha rich in cycloparaffins would be a better feedstock to catalytic reforming units because cyclo-paraffins are easily dehydrogenated to aromatic compounds. Table 2-5 is a typical analysis of naphtha from two crude oil types. 

The main use of naphtha in the petroleum industry is in gasoline production. Light naphtha is normally blended with reformed gasoline (from catalytic reforming units) to increase its volatility and to reduce the aromatic content of the product gasoline. 

The feed to a catalytic reformer is normally a heavy naphtha fraction produced from atmospheric distillation units. Naphtha from other sources such as those produced from cracking and delayed coking may also be used. Before using naphtha as feed for a catalytic reforming unit, it must be hydrotreated to saturate the olefins and to hydrodesulfurize... 

Naphtha to become a suitable component tor blending into finished gasoline pools must be further processed. The octane number will range from 40 to 50. Prior to introduction into a catalytic-reforming unit, most naphtha feedstocks are hydrotreated in the interest of prolonging the life of the reforming catalyst. 

Fauconnier JC, Gorenflo F, Thomas R. A shell-and-plate heat exchanger for the catalytic reforming unit at O.M. refinery Karlsruhe. Eurotherm 33, Recent Developments in Heat Exchanger Technology, Paris E.E.T.I., 1994 313-320. 

National Emission Standards for Hazardous Air Pollutants for Primary Copper Smelting National Emission Standards for Hazardous Air Pollutants for Secondary Aluminum Production National Emission Standards for Hazardous Air Pollutants for Primary Lead Smelting National Emission Standards for Hazardous Air Pollutants for Petroleum Refineries Catalytic Cracking Units, Catalytic Reforming Units, and Sulfur Recovery Units... 

Regeneration of Catalytic reforming units which includes some catalyst with high levels of residual graphitic carbon levels and high density "collapsed" particles. 

The feedstock consists of a mixture of C8 aromatics typically derived from catalytically reformed naphtha, hydrotreated pyrolysis gasoline oran LPG aromatization unit. The feed may contain up to 40% ethylbenzene, which is converted either to xylenes or benzene by the Isomar reactor at a high-conversion rate per pass. Feedstocks may be pure solvent extracts or fractional heartcuts containing up to 25% nonaromatics. Hydrogen may be supplied from a catalytic reforming unit or any suitable source. Chemical hydrogen consumption is minimal. 

The process specifications on raw material speed through furnaces coils imposed the use of two or four parallel passes, e.g. the fumaees from the atmospherie distillation unit, vacuum distillation unit, catalytic reforming unit, coker unit, catalytic cracking unit. The conventional control structure of radiant section for a typical tubular furnace from the atmospheric distillation unit (output capacity 3.5 Mt/year) is presented in figure 1 [1]. Because the conventional temperature control system only controls one outlet temperature or in the best case the temperature of the mixing point, in current operations there are several situations [1, 2, 3] ... 

For desulfurizers, coking, and catalytic reforming units, many of the pressure vessels operating with metal temperatures of 700 to 900°F are constructed, from carbon-V2 Mo or IV4 Cr-V2 Mo alloy steels. These steels have marked creep-rupture strength properties over carbon steel. For example, compare the design stress value of 15,000 psi for IV4 Cr-V2 Mo steel at 900°F with the 6,500 psi value for carbon steel at the corresponding temperature. 

Pollutants for Petroleum Refineries Catalytic Cracking Units, Catalytic Reforming Units, and Sulfur Recovery Units... 

Typical conditions for semiregenerative catalytic reforming units are given below in table 1. In this table feed PONA analysis, H2/HC molar ratio and operation conditions are given. 

Currently, there are more than 700 commercial installations of catalytic reforming units worldwide with a total capacity of about 11.4 million barrels per day (b/d). Table 1 presents a worldwide distribution of catalytic reforming capacity. " About 40% of this capacity is located in North America followed by 20% each in Western Europe and Asia-Pacific region. 

Wherever the situation warranted either one or all of the processes were used to maximize benzene and xylenes production in lieu of toluene which used to be produced in surplus quantities in a catalytic reforming unit of a petroleum refinery. 

A typical catalytic reforming unit consists of a number of fixed-bed reactors, frequently four, in series. The naphtha feedstock is vaporized and heated to the desired reaction temperature, then admitted to the first reactor. As the components in the naphtha undergo reaction during passage through the catalyst bed, the temperature of the vapor stream decreases by 70-100 C due to the endothermicity of the reaction. The major reaction occurring in the first catalyst bed is the dehydrogenation of cycloalkanes to aromatics. 

Needless to say, anytime something like this comes along you get a fair number of competitors, so that the total volume of gasoline produced in platinum containing catalytic reforming units is very large. In fact, at the present time one would be hard pressed to buy gasoline which did not contain a portion processed over a platinum catalyst. 

The advantages of CCR Platforming over SR Platforming are so overwhelming that essentially all new catalytic reformers units are designed with continuous regeneration. 

Integrity and life assessment of catalytic reformer units 19... 

---