Patent EA-002038-B1 (EA)
Title: Process for conversion of hydrocarbons and device for implementation same
Inventor: CZERNICHOWSKI M ALBIN
IPC: C01B3/34
Filed: 1998-08-28
Abstract: 1. Process for the conversion of hydrocarbons comprising such as methane CH4, ethane C2H6, propane C3H8 and butanes C4H10, by partial oxidation with elemental oxygen O2 or by simultaneous reforming with O2 and water vapor H2O, characterized in that that one (or several) hydrocarbon(s) mixed with water vapor and/or oxygen is (are) exposed to a guiding electric discharge plasma in a gliding electric arc in order to generate and maintain chemical reactions of partial or total conversion of such mixture into a synthesis gas, the latter being a mixture of hydrogen H2 and carbon monoxide CO; this synthesis gas may be accompanied by unsaturated hydrocarbons such as ethylene C2H4 and/or acetylene C2H2 produced by the same conversion process. 2. Process according to claim 1, characterized by the fact that one (or several) such hydrocarbon(s) to be converted, referred to as the feedstock, enter in contact with the electric discharges, provided that said feedstock is mixed with gaseous oxygen with a O2/feedstock volume ratio at least equal to 0.22, knowing that such mixture may also contain any proportion of water vapor H2O and/or nitrogen N2 and/or carbon dioxide CO2, and that the mixture that contains the feedstock and the oxygen, possibly with H2O and/or N2 and/or CO2, is of natural origin or derived from an industrial activity, or prepared intentionally prior to its introduction in the electric discharge reactor, or prepared intentionally in the reactor itself by the separate introduction of preheated gases. 3. Process according to claims 1 and 2, characterized by the fact that the elemental oxygen O2 pure or contained in the oxygen-enriched air, or even in the atmospheric air, is partially or totally converted into carbon monoxide CO by reacting with one (or several) hydrocarbon(s) in contact with electric discharges, with or without the presence of water vapor and/or carbon dioxide. 4. Process according to claims 1 to 3, characterized by the fact that the conversion is performed in the presence of a metal or ceramic body /19/ brought to a temperature not exceeding 1100 degree C and placed in contact with a flow of products resulting from the partial conversion by electric discharge plasma, knowing that said body becomes active, in relation to the process of conversion of the feedstock into synthesis gas, only in the presence of said flow of products exiting the electric discharge zone and that, without said flow, the body deactivates itself in relation to the process. 5. Process according to claims 1 to 4, characterized by the fact that the conversion is achieved at a pressure ranging from 7 kPa to 6 bars, and that the temperature of the conversion, defined as the temperature of any solid element placed in contact with electric discharges, is less than 1200 degree C. 6. Process according to claims 1 to 5, characterized by the fact that the conversion products contain H2 and CO, accompanied possibly by ethylene and/or acetylene, the relative H2/CO contents, expressed in mol/mol or volume/volume, being comprised between 0.46 and 3.05. 7. Process according to claims 1 to 6, characterized by the fact that the conversion is achieved without the hydrocarbon feedstock being decomposed into soots, cokes or tars, in relative quantities exceeding 0.5%, expressed in mass of carbon converted during the process. 8. A device (1) for the implementation of the process of claims 1 to 7, comprising: a structure to produce the gliding electric discharge plasma (4), said structure comprising a plasma compartment (15a) and a post-plasma compartment (15b); a nozzle (5) in the plasma compartment (15a) for introducing premixed fluid (6) to be converted or reactants; a diaphragm or the like separating device that is constructed and mounted between the plasma compartment and post-plasma compartment where the plasma compartment (15a) communicates with the post-plasma compartment (15b) without discharges such that the reactants in the plasma compartment (15a) are reinforced and recirculated and at the same time to allow the gas to flow between the plasma compartment (15a) and the post-plasma compartment (15b) where the chemical species contained in the products of the contact between the reactants and the discharges contribute, in the presence of a metal or ceramic body (19) to the conversion of the products exiting the plasma compartment (15a).