Heavy fossil hydrocarbon conversion and upgrading using radio-frequency or microwave energy
Conversion of heavy fossil hydrocarbons (HFH) to a variety of value-added chemicals and/or fuels can be enhanced using microwave (MW) and/or radio-frequency (RF) energy. Variations of reactants, process parameters, and reactor design can significantly influence the relative distribution of chemicals and fuels generated as the product. In one example, a system for flash microwave conversion of HFH includes a source concentrating microwave or RF energy in a reaction zone having a pressure greater than 0.9 atm, a continuous feed having HFH and a process gas passing through the reaction zone, a HFH-to-liquids catalyst contacting the HFH in at least the reaction zone, and dielectric discharges within the reaction zone. The HFH and the catalyst have a residence time in the reaction zone of less than 30 seconds. In some instances, a plasma can form in or near the reaction zone.
1. A method for continuous flash conversion of heavy fossil hydrocarbons (HFH), the method comprising:
simultaneously providing both a continuous HFH feed and hydrogen-containing process gas feed to a reaction zone, wherein a mass ratio of the HFH feed to the hydrogen-containing process gas is greater than 3:1;
dispersing the HFH feed in the process gas while maintaining a pressure of greater than 0.9 atm within the reaction zone; and
concentrating microwave or RF energy in the reaction zone using a microwave or RE energy source to generate dielectric discharges within the reaction zone to flash convert the HFH.
2. The method of claim 1 wherein the HFH feed comprises one or more of coal, coal/biomass blends, oil sands, petroleum fractions, coke, char recycle, coal-derived materials.
3. The method of claim 1 wherein the HFH feed comprises coal.
4. The method of claim 3 further comprising continuously feeding the coal.
5. The method of claim 1 wherein the HFH feed comprises coal entrained in a reactive process gas.
6. The method of claim 1 wherein the hydrogen-containing process gas comprises one or more of nitrogen, carbon dioxide, methane, natural gas, recycle gas, carbon monoxide, argon, helium, water vapor, and/or oxygen.
7. The method of claim 1 wherein the ratio of HFH feed to the process gas is greater than 6:1.
8. The method of claim 1 wherein the HFH feed is pre-mixed with a portion of the process gas.
9. The method of claim 1 wherein the process gas feed is provided through a gas injector.
10. A method for continuous flash conversion of heavy fossil hydrocarbons (HFH), the method comprising:
continuously dispersing a HFH feed within a process gas to form a mixture of the HFH feed and the process gas within a reaction zone maintained at a pressure of greater than 0.9 atm, wherein the mixture comprises hydrogen, and a mass ratio of the HFH feed to the process gas within the mixture is greater than 3:1; and
concentrating microwave or RF energy in the reaction zone using a microwave or RF energy source to generate dielectric discharges within the reaction zone to flash convert the HFH.
11. The method of claim 10 wherein the mixture comprises at least 0.5 weight percent HFH feed.
12. The method of claim 10 wherein the mixture comprises less than 95 weight percent HFH feed.
13. The method of claim 10 further comprising forming an ionized argon plasma within the reaction zone.
14. The method of claim 10 wherein the mixture resides in the reaction zone for less than 30 seconds.