High temperature hydropyrolysis of carbonaceous materials

Abstract

Heat from a concentrated solar power source is applied to the conversion of carbonaceous materials such as heavy petroleum crude oils, coals and biomass to liquid hydrocarbons. The solar heat is applied to provide at least a portion of the process heat used in the high temperature, short contact time hydropyrolysis of the carbonaceous material which is supplied with hydrogen generated by a high temperature process such as high temperature steam electrolysis, the sulfur-iodine cycle, the hybrid sulfur cycle, the zinc-zinc oxide cycle or by methane steam cracking. The heat from the solar source may be used to generate electricity to operate high temperature steam electrolysis used in generation of the hydrogen. By the use of solar thermal energy sources, hydrocarbon resource utilization for process heat is eliminated along with carbon dioxide evolution associated with burning of the hydrocarbon resource to generate process heat. The substitution of zero carbon emission sources therefore offers the potential for significant carbon emission reductions in refinery operations where external process heat can be applied and effectively utilized.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority under 35 USC 120 from Application Ser. No. 61 / 268,779, filed 16 Jun. 2009. It is also related to Application Ser. No. 60 / 268,776, of even date, which relates to the pyrolysis of carbonaceous materials at high temperatures using external process heat from a nuclear heat source.FIELD OF THE INVENTION[0002]This invention relates to the pyrolysis of carbonaceous materials and more particularly to the hydropyrolysis of carbonaceous materials at high temperatures using external process heat from solar heat sources.BACKGROUND OF THE INVENTION[0003]The petroleum refinery is one of the most thoroughly integrated operations in existence: apart from contaminants, all that goes into the refinery is either consumed in processing or emerges as useful product. Increasing shortages of crude oil and their accompanying price increases together with the unpredictable instabilities of many crude-producing regions have resulte...

AI Technical Summary

Benefits of technology

[0008]The heat for the endothermic cracking reactions is efficiently supplied by solar thermal energy sources, with the heat transferred from a concentrated solar power source either directly by taking the feedstream through the focus of the solar unit or indirectly by the use of a suitable heat transfer medium fed through the solar focus point and then passed to the reactor.

[0009]The solar heat is applied to the pyrolyis either directly by routing the pyrolyis feedstream through the focus point of the solar furnace or, alternatively, by the use of a heat transfer medium and heat exchange device transferring the heat from the solar power source to the process unit in which the process is being operated or to the power cells used for producing electricity. Concentrated solar power (CSP) sources have the capability to generate very high temperatures potentially in excess of 1500° C. and heat of this quality can be used very effectively to provide process heat to the hydropyrolysis and to the other specified uses. High temperature heat transfer from a concentrated solar power source can be effected using transfer media such as liquids, gases, molten salts or molten metals although molten salts and molten metals will often be preferred for their ability to operate at very high temperatures for high energy densities without phase changes; in addition, corrosion problems can be minimized by appropriate choice of medium relative to the metallurgy of the relevant units.

[0012]Solar thermal energy sources are zero carbon emission sources and by using them, hydrocarbon resource utilization for process heat is eliminated along with carbon dioxide evolution associated with burning of the hydrocarbon resource to generate process heat. For perspective, each liter of petroleum resid requires approximately 140 liters of natural gas (methane at 15.5° C.) to heat it to 540° C. and hold it at that temperature for six seconds and, as noted above, about 20 to 25 percent of the crude oil input to a refinery is used in processing. The substitution of zero carbon emission sources therefore offers the potential for significant carbon emission reductions in refinery operations where external process hear can be applied and effectively utilized.

Problems solved by technology

Second, the heat is used to generate hydrogen by a high temperature process such as high temperature steam electrolysis, the sulfur-iodine cycle, the zinc-zinc oxide cycle or even, more conventionally, by steam cracking.

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