Fluid barriers
A fluid barrier along the inside surface of ductwork between a reactor and subsequent product separation and recovery apparatus to reduce the buildup of solids on the ductwork from a gaseous product mixture conveyed through the ductwork. Barrier fluid is sprayed along the internal surface of the ductwork to form a fluid barrier and cool the gaseous mixture. The barrier fluid can be comprised of a component of the gaseous mixture. The barrier fluid can be a liquid at the second temperature and converted to a gaseous state in the ductwork, using the heat of vaporization of the barrier fluid to help cool the gaseous mixture.
1. A method for reducing solids buildup on an internal surface of ductwork between a reactor and subsequent product separation and recovery apparatus for conveying, at a first temperature, a gaseous product mixture containing materials which are otherwise deposited on the ductwork as tacky solids at said first temperature, comprising the step of introducing a barrier fluid at a second temperature, lower than the first temperature, along the internal surface of the ductwork to form a fluid barrier.
2. A method according to claim 1 , wherein the materials otherwise deposited as tacky solids include volatile metal chlorides.
3. A method according to claim 2 , wherein the volatile metal chlorides contain one or more chlorides selected from the group consisting of chlorides of Fe, Mn, Ni, Si, Al, Nb, Zr, V, Mg, and Ca.
4. A method according to claim 1 , wherein the chlorides include solid chlorides.
5. A method according to claim 1 , wherein the barrier fluid is a liquid at the second temperature.
6. A method according to claim 1 , wherein the barrier fluid is comprised of a material already present in the gaseous mixture.
7. A method for reducing chloride buildup on the internal surface of ductwork conveying, at a first temperature, a gaseous mixture containing such chlorides, comprising the step of introducing a barrier fluid at a second temperature, lower than the first temperature, along the internal surfaces of the ductwork to form a fluid barrier, wherein the barrier fluid is a liquid at the second temperature.
8. A method according to claim 7 , wherein the barrier fluid and second temperature are chosen so that the barrier fluid is vaporized in the ductwork.
9. A method according to claim 7 , wherein the barrier fluid is comprised of a material already present in the gaseous mixture.
10. A method for reducing chloride buildup on the internal surface of ductwork conveying, at a first temperature, a gaseous mixture containing volatile metal chlorides and titanium tetrachloride, comprising the step of introducing a barrier fluid at a second temperature, lower than the first temperature, along the internal surfaces of the ductwork to form a fluid barrier.
11. A method according to claim 10 , wherein the barrier fluid comprises nitrogen, carbon dioxide, or titanium tetrachloride.
12. A method according to claim 10 , wherein the barrier fluid is titanium tetrachloride.
13. A method according to claim 10 , wherein the barrier fluid is a liquid.
14. A method according to claim 10 , wherein the first temperature is from about 800° C. to about 1400° C.
15. A method according to claim 10 , wherein the second temperature is from about 60° F. (15.6° C.) to about 100° F. (37.8° C.).
16. A method for reducing chloride buildup on the internal surface of ductwork conveying, at a first temperature, a gaseous mixture containing volatile metal chlorides and titanium tetrachloride, comprising the step of spraying liquid titanium tetrachloride at a second temperature, lower than the first temperature, along the internal surface of the ductwork to form a fluid barrier.
17. A method according to claim 16 , wherein the first temperature is from about 800° C. to about 1400° C.
18. A method according to claim 16 , wherein the second temperature is from about 60° F. (15.6° C.) to about 100° F. (37.8° C.).