Resumen
[0001] Direct thermal decomposition of hydrocarbons into solid carbon and hydrogen is performed by a process and a device. The process comprises preheating a hydrocarbon gas stream to a temperature between 500° C. and 700° C. and injecting the pre-heated hydrocarbon gas stream into the reactor pool of a liquid metal reactor containing a liquid media; forming a multi-phase flow with a hydrocarbon gas comprising hydrogen and solid carbon at a temperature between 900° C. and 1200° C.; forming a carbon layer on the free surface of the liquid media made up of solid carbon particles which are then displaced into at least one carbon extraction system and at least one recipient for collecting them; and, at the same time, the gas comprising hydrogen leaves the reactor pool through a porous rigid section, being collected at a gas outlet collector from where the gas comprising hydrogen finally leaves the liquid metal reactor.
Reivindicaciones
1. A process for the direct thermal decomposition of hydrocarbons into solid carbon and hydrogen comprising: a. preheating a hydrocarbon gas stream conducting the hydrocarbon gas stream from at least one hydrocarbon gas stream inlet (1), located at the top part of a liquid metal reactor, to the bottom part of the liquid metal reactor, through a pre-heating conduct (7) located surrounding the external perimeter of the liquid metal reactor, said pre-heating conduct (7) being located inside a thermal insulation means (18), obtaining a pre-heated hydrocarbon gas stream at a temperature between 500 and 700°C; b. injecting the pre-heated hydrocarbon gas stream obtained in step (a) into the liquid metal reactor, in particular, into a reactor pool (13) of the liquid metal reactor containing a liquid metal media (5), wherein said injection takes place at the bottom part of the liquid metal reactor through a porous section or a set of gas injection orifices (3); c. the hydrocarbon gas injected into the liquid metal reactor in step (b) moves upwards by buoyancy forming a multi-phase flow, a hydrocarbon gas comprising hydrogen and solid carbon, at the same time that the liquid metal media (5) inside the reactor pool is maintained at a temperature comprised between 900 and 1200°C; d. the solid carbon obtained in step (c) is accumulated at the top of the reactor pool, on the free surface of the liquid metal media (5) located inside the liquid metal reactor, forming a carbon layer (8) made up of solid carbon particles (19); e. once the carbon layer (8) reaches a determined thickness, the carbon particles (19) constituting the carbon layer (8) are displaced into at least one carbon extraction system consisting of a porous rigid section (9) located at the top of the liquid metal reactor, above the free surface of the liquid metal media (5), from which the carbon particles (19) are conducted into at least one recipient for collecting the carbon particles (10); f. at the same time, the gas comprising hydrogen obtained in step (c) leaves the reactor pool through the porous rigid section (9), being collected at a gas outlet collector (16) from where the gas comprising hydrogen finally leaves the liquid metal reactor. 2. A process according to claim 1, wherein the temperature inside the reactor pool is reached by means of at least one thermal heater (4) located inside the reactor pool (13). 3. A process according to claim 1 or 2, wherein the thickness of the carbon layer (8) reached in step (c) is between 1 and 15 cm. 4. A process according to any one of claims 1 to 3, wherein the conduction of the carbon particles (19) towards the recipient for collecting said carbon particles (19) is facilitated by a vibrational movement generated by a mechanical shaft (12). 5. A device for carrying out the process as claimed in any one of claims 1 to 4, comprising: a. a pre-heating conduct (7) comprising at least one hydrocarbon gas inlet (1) located at the top of the liquid metal reactor and at least one hydrocarbon gas outlet located at the bottom part of the liquid metal reactor corresponding to the hydrocarbon gas inlet into the liquid metal reactor, and in particular into a reactor pool (13) designed for containing a liquid metal media (5), wherein said pre-heating conduct (7) is located inside a thermal insulation means (18); b. the liquid metal reactor further comprises at least one thermal heater (4) located inside the reactor pool (13) for inducing an homogeneous temperature inside the liquid metal reactor; c. in addition, at the top of the liquid metal reactor, at least one carbon extraction system consisting of a porous rigid section (9) is located, said porous rigid section (9) being connected to at least one recipient suitable for collecting carbon particles (10); d. finally, the porous rigid section (9) also incorporates, at the top of it, a carbon barrier (15) designed for the carbon particle (19) retention, wherein said carbon barrier (15) separates the porous rigid section (9) from a gas outlet collector (16). 6. The device, according to claim 5, wherein the connection between the porous rigid section (9) and the recipient suitable for collecting carbon particles (10) further incorporates mechanical means (12) for facilitating the movement of the solid carbon particles (19).
