Synthetic crude, hydrogen requirements

The estimated future U. S. requirements of hydrogen for petroleum refining are based on the forecasted quantities of crude oil, natural gas liquids (NGL), synthetic crudes, and imported crudes shown in Table 4. During the 1980-2000 period, U. S. crude runs will increase from 15.3 to 18.0 million B/D while the total U. S. liquid hydrocarbon supply, including product imports, will increase slightly from 19.7 to 21.1 million B/D. The total liquid supply corresponds to 40 and 43 Quad/year for 1980 and 2000. By the year 2000, there will be a substantial increase in the quantity of residuum converted due to an overall increase in the quantities of heavy crudes in the crude slate. 

Hydrogen Requirements in Shale Oil and Synthetic Crude from Coal... 

The process conditions (which may be on the order of 345°C-370°C [650°F-700°F]) can be altered appropriately to produce different product slates (Table 19.8). For example, synthetic crude production usually requires higher temperatures and higher hydrogen (partial) pressures than the process conditions for the production of low-sulfur residual oils. This latter operational mode requires that less hydrogen be consumed. In this respect, it must be remembered that the H-Coal process can require as much as 20,000 ft hydrogen per ton of coal processed. 

The final transformation of (—)-546 into alkaloid (—)-378, performed on the crude diol, required intermediate protection as the acetonide, after which cleavage of the benzyl ether with hydrogen and palladium(II) chloride followed by hydrolysis of the acetal with aqueous acid completed the synthetic route. 

The major chemical difference between natural gas, crude oil, and coal is their hydrogen-to-carbon ratios. Coal is carbon-rich and hydrogen-poor, so to produce a synthetic liquid or gas from coal requires an increase in the hydrogen-to-carbon ratio. Coal s ratio of about 0.8 has to be raised to 1.4 to 1.8 for a... 

The projected synthetic fuels program involving conversion of coal and shale may have a profound effect on available supplies of sulfur and supply patterns. Desulfurization of intermediate process streams to hydrogen sulfide will be required to meet environmental standards. Conversion of intermediate hydrogen sulfide to elemental sulfur will be carried out as in the case of crude oil desulfurization. Elemental sulfur represents the preferred sulfur... 

Since hydrogenation processes are likely to be ruled out because they require the operation of extremely high-pres-siue reactors, atmospheric pressiue processes, such as delayed coking, are likely to prevail in the production of synthetic light crudes at a low price whenever a coke by-... 

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