Hydrotreaters, gases from

The lig t distillate product pump, which supplied lean oil to the absorber, lost suction at startup. Gas from the absorber backed through the lean oil line and traveled into the hydrotreater charge pump, causing it to gas up and lose suction. This resulted in hydrotreater catalyst damage. 

The H2/Oil ratios are for units in which off-gas from the high-pressure separator is recycled. For once-through naphtha hydrotreaters associated with catalytic reformers, the H2/Oil ratio can be much higher than 350 scf bbl (60 m /w ). For units that treat olefinic cracked stocks from FCC or coking units, H2/Oil ratios are higher to control the extra heat released by olefin saturation. 

Bench scale tests of the application of the UCBSRP process to recycle gas from a crude oil residuum hydrotreater and to a coal gasification stream were reported, respectively, by Lynn et al. (1987) and by Neumann and Lynn (1986). 

The gas oils from visbreaking and coking have better cetane numbers than LCO but they are unstable and need hydrotreatment before they can be used. 

The cat products become feed to other units, such as alkylation and polymerization plants. High boiling liquid products are used to make lubes, and the gas goes into the refinery fuel systems. Cat cracking feed stocks come from atmospherie and vacuum stills, phenol extraction plants, hydrotreaters, deasphalters and cokers. 

Products from coking processes vary considerably with feed type and process conditions. These products are hydrocarbon gases, cracked naphtha, middle distillates, and coke. The gas and liquid products are characterized by a high percentage of unsaturation. Hydrotreatment is usually required to saturate olefinic compounds and to desulfurize products from coking units. 

Carbazole is a non-basic nitrogen compound, whose removal via hydrotreating is limited by its low reactivity. The removal of nitrogen by hydrotreatment involves a number of steps that take place on the catalyst surface. The weak interaction of neutral nitrogen compounds with catalysts precludes carbazole and its derivatives from being denitro-genated and makes them the most recalcitrant components in HDN of gas oils [308], In fact, it has been found that the nitrogen content of hydrotreated gas oil from Athabasca bitumen was composed primarily of alkyl carbazoles [309],... 

Diesel production involved a straightforward design. The olefinic distillate from olefin oligomerization was combined with the straight-run HTFT distillate and hydrotreated. The hydrotreated Fischer-Tropsch-derived distillate was blended with the distillate fraction from the natural gas liquids to produce diesel fuel. In 2003 another hydrotreater (noble metal catalyst) was added to the refinery to convert part of the hydrotreated HTFT distillate into low aromatic distillate to serve a niche market.56... 

The primary purpose of the energy conversion facility is the production of liquid or gaseous fuels most of the sulfur will be removed from these products. Liquid fuel streams will be hydro-desulfurized to meet combusion standards, with the sulfur transferred to the gas phase. In the case of oil shale, extensive hydrotreatment will be required to remove the refractory nitrogen compounds from the oil. With this degree of treatment, the sulfur will also be removed. 

The results from the supercritical hydrotreatment experiments are superior in almost every respect to conventional hydrotreatment experiments (without the use of solvent). Under similar conditions, supercritical hydrotreating produced better products, for example less gas yield (10 vs 25 ), more of light oil fraction, <300F, (55 vs 35 ) and less coke formed on the catalyst surface (0.3 vs 3.8 based on the feed). For... 

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