Hydrotreated feed

Problems sulfur and nitrogen transferred to the products (and coke) Solutions feed hydrotreating, reduction of S, N, Conradson carbon, metals Results higher quality products reduction in pollution better yields of valuable products reduced post-treatment... 

FCC feed hydrotreating Gasoline end point reduction FCC gasoline hydrotreating Catalyst additives Bio-catalytic desulfurization... 

Feed hydrotreating or hydrocracking reduces SOj, emissions and the sulfur content of FCC products. As discussed earlier in this chapter, many benefits are associated with FCC feed hydrotreating. It is important to note that most of the sulfur in a hydrotreated feed is in heavy organic compounds and will be concentrated in the decanted oil and coke. Consequently, for a given sulfur in the feed, more SO, will be produced with hydrotreated feed. 

Figure 16.5 Impact of pretreating severity on the activity of a hydrocracking catalyst temperature required for conversion of a feed hydrotreated to (a) 40 ppm nitrogen, (b) 10ppm nitrogen.

Finally, PILC, REY-PILC, and a commercial equilibrium catalyst were evaluated at near constant conversion using a heavier feed, hydrotreated resid. The product yields are shown in Table III. Steam deactivated (D), REY-PILC, produced the same gasoline selectivity, LCO/HCO ratio, and coke yield as calcined PILC. The equilibrium catalyst which represents a more severely deactivated (E) sample had higher gasoline selectivity, lower coke yield, and lower HCO/LCO ratio. The higher coke yield of REY-PILC could be due to occlusion of high molecular weight hydrocarbons in the microstructure of the pillared clay. 

Marathon s strategy was to leverage future clean fuels projects to minimize capital investment and maximize emission reductions. Units with feed hydrotreating capacity typically used catalyst additives. Units with no hydroprocessing typically relied upon other technology options in conjunction with catalyst additives. Since each application was unique, implementation was required over a period of time. Figure 14.5 shows the timeline when significant events occur for the Marathon CD. 

For many refineries, switching to a low sulfur feed is both expensive and unrealistic. Feed hydrotreating is the most capital intensive of the available solutions. 

The FCC process is the most common conversion unit in use today. As such, it is important to determine the performance of an FCC when feeding hydrotreated shale oil. The two 650° F+ feeds shown in Table VI were evaluated in an FCC pilot plant operating in a fixed fluidized-bed mode. The catalyst was withdrawn from an operating commercial FCC unit. It is a zeolite catalyst, CBZ-1, produced by Davison Chemical Division of W. R. Grace and Company and is moderately active as well as contaminated with metals. 

D.C. McCulloch, Advantages of Cat Feed Hydrotreating. Paper presented at the 1975 NPRA Annual Meeting, San Antonio, Texas, March 23-25, 1975. 

Table 7. Impact of Feed Hydrotreating on FCC Unit Perfortnance...

Hydrotreating refers to a relatively mild operation whose primary purpose is to saturate olefins and/or reduce sulfur and nitrogen content without changing too much the boiling range of the feed. Hydrotreating is applied to a wide range of feedstocks from naphtha to reduced crude oil. If the process is used specifically for sulfur removal, it is usually called hydrodesulfurization or HDS. 

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