US-12623907-B2 - Carbon separation and removal from molten media

US12623907B2US 12623907 B2US12623907 B2US 12623907B2US-12623907-B2

Abstract

A reaction system comprises a reactor vessel, a secondary vessel, a transfer line providing fluid communication between the reactor vessel and the secondary vessel, a return line providing fluid communication between the secondary vessel and the reactor vessel, a filter disposed within the secondary vessel, and at least one freeze plug valve disposed within the transfer line or the return line.

Inventors

Brett PARKINSON
Andrew Caldwell
Samuel SHANER

Assignees

Molten Industries Inc.

Dates

Publication Date: 20260512
Application Date: 20210827

Claims (12)

1 . A method of separating a product from a molten media, the method comprising: passing a hydrocarbon gas through a molten media in a reactor vessel to produce reaction products, wherein the reaction products comprise hydrogen and solid carbon, wherein the solid carbon is retained in the molten media; passing the molten media with the solid carbon through a transfer line to a secondary vessel; separating the solid carbon from the molten media in the secondary vessel to form a filter cake; forming a first frozen plug in the transfer line; passing the molten media from the secondary vessel back to the reactor vessel through a return line; and forming a second frozen plug in the return line, wherein the reactor vessel is sealed from the secondary vessel by the first frozen plug in the transfer line and the second frozen plug in the return line.
2 . The method of claim 1 , wherein separating the solid carbon from the molten media comprises filtering the solid carbon from the molten media in the secondary vessel.
3 . The method of claim 1 , further comprising: drying/cleaning the solid carbon after separating the solid carbon from the molten media.
4 . The method of claim 1 , wherein the solid carbon has a molten media content of between 50-98 wt. % after separating the solid carbon from the molten media, and wherein the solid carbon has a molten media content of between 0-80 wt. % after drying/cleaning the solid carbon.
5 . The method of claim 1 , wherein the molten media comprises one or more oxidized atoms (M) +m and corresponding reduced atoms (X) −1 , wherein M is at least one of K, Na, Mg, Ca, Mn, Zn, La, Al, or Li, and wherein X is at least one of F, Cl, Br, I, OH, SO 3 , or NO 3 .
6 . The method of claim 1 , wherein the molten media comprises nickel, bismuth, copper, platinum, indium, lead, gallium, iron, palladium, tin, cobalt, tellurium, ruthenium, antimony, gallium, sodium, oxides thereof, or any combination thereof.
7 . The method of claim 1 , wherein the reactor vessel operates at a temperature in the range of between about 700° C. and about 1,400° C.
8 . The method of claim 1 , wherein at least one of the first frozen plug or the second frozen plug is disposed in a straight section of the transfer line or the return line, respectively.
9 . The method of claim 1 , wherein at least one of the first frozen plug or the second frozen plug is disposed in a bent or curved section of the transfer line or the return line, respectively.
10 . The method of claim 1 , wherein forming the first frozen plug in the transfer line comprises: passing the molten media through the transfer line; cooling the molten media in the transfer line; and freezing the molten media in the transfer line to form the first frozen plug.
11 . The method of claim 1 , further comprising: stirring the filter cake in the secondary vessel to remove the molten media from the filter cake.
12 . The method of claim 11 , further comprising: heating the filter cake during the stirring to remove the molten media from the filter cake.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a filing under 35 U.S.C. 371 as the National Stage of International Application No. PCT/US2021/047952, filed on Aug. 27, 2021, entitled, “CARBON SEPARATION AND REMOVAL FROM MOLTEN MEDIA,” which claims the benefit of and claims priority to U.S. Provisional Application No. 63/071,857 filed on Aug. 28, 2020 and entitled, “CARBON SEPARATION AND REMOVAL FROM MOLTEN MEDIA,” both of which are incorporated herein by reference in their entirety for all purposes. STATEMENT REGARDING GOVERNMENTALLY SPONSORED RESEARCH OR DEVELOPMENT This invention was made with government support under Grant DE-AR0001194 awarded by the Department of Energy. The government has certain rights in this invention. BACKGROUND The transformation of chemical feedstocks into products relies on reactors with controlled internal conditions. Conversion of hydrocarbon feedstocks such as natural gas containing methane with strong carbon-hydrogen bonds is particularly challenging and typically utilizes reactors containing catalysts and/or making use of high temperatures. A major limitation in chemical reaction engineering is the inability to perform very high temperature reactions efficiently at high pressure due to the limitations of reactor construction materials. For reversible reactions, equilibrium limitations, can also make very high temperatures desirable but limited by reactor material considerations. This is especially true in corrosive environments. Above approximately 1000° C. few moderate cost materials can be used for construction of safe pressure vessels and the associated reactor equipment. SUMMARY These and other features will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings and claims. In some embodiments, a reaction system comprises a reactor vessel, a secondary vessel, a transfer line providing fluid communication between the reactor vessel and the secondary vessel, a return line providing fluid communication between the secondary vessel and the reactor vessel, a filter disposed within the secondary vessel, and at least one freeze plug valve disposed within the transfer line or the return line. In some embodiments, a carbon removal system comprises a vessel, a filter disposed within the vessel, an agitator disposed within the vessel, and a liquid sump in a lower portion of the vessel. The agitator is configured to agitate a filter cake formed on the filter. In some embodiments, a method of separating a product from a molten media comprises passing a hydrocarbon gas through a molten media in a reactor vessel to produce reaction products, passing the molten media with the solid carbon through a transfer line to a secondary vessel, separating the solid carbon from the molten media in the secondary vessel to form a filter cake, forming a first frozen plug in the transfer line, passing the molten media from the secondary vessel back to the reactor vessel through a return line, and forming a second frozen plug in the return line. The reaction products comprise hydrogen and solid carbon, and the solid carbon is retained in the molten media. The reactor vessel is sealed from the secondary vessel by the first frozen plug in the transfer line and the second frozen plug in the return line. BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the present disclosure, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description: FIG. 1 schematically illustrates a reactor system according to an embodiment. FIG. 2 schematically illustrates another reactor system according to an embodiment. FIG. 3 schematically illustrates still another reactor system according to an embodiment. FIG. 4 schematically illustrates yet another reactor system according to an embodiment. FIG. 5 schematically illustrates another reactor system according to an embodiment. DETAILED DESCRIPTION Disclosed herein are systems and methods for the separation and cleaning of carbon produced via hydrocarbon pyrolysis from molten media. The systems and methods described herein are based on transformation of natural gas or other molecules or mixtures of molecules containing predominately hydrogen and carbon atoms into a solid carbon product that can be readily handled and prevented from forming carbon oxides in the atmosphere, as well as a gas phase co-product. In some embodiments, the gas-phase co-product, hydrogen, can be used as a fuel or chemical. The overall process in this case can be referred to as pyrolysis, CnH2m→mH2+nC. A key challenge with hydrocarbon pyrolysis in molten media systems is the separation of the carbon from the molten media and the removal of residual media from the carbon. Due to the high temperatures involved, the systems described herein are configured to use freeze plug valves within the carbon/molten media transfer lines to isolate the v