Reactor apparatus and methods for reacting compounds
View Patent ↗Shell and tube heat exchangers that include a baffle arrangement that improves the temperature profile and flow pattern throughout the exchanger and/or that are integral with a reaction vessel are disclosed. Methods for using the exchangers including methods that involve use of the exchanger and a reaction vessel to produce a reaction product gas containing trichlorosilane are also disclosed.
1. A reactor apparatus for reacting one or more compounds in a reactor feed gas and exchanging heat between the reactor feed gas and a reactor product gas, the apparatus comprising:
a reaction vessel having a wall and comprising a reaction chamber in which the reaction occurs;
a shell and tube heat exchanger for transferring heat between the reactor feed gas and product gas, the shell and tube heat exchanger comprising:
a shell that is in fluid communication with the reaction chamber;
a tube bundle within the shell, the tube bundle extending through the wall into the reaction chamber, the bundle comprising a plurality of central tubes and a plurality of peripheral tubes between the central tubes and the shell, the tubes being in fluid communication with the reaction chamber; and
a (1) terminal flange or (2) baffle within the reaction chamber for securing the portion of tubes that extends into the reaction chamber; and
a reactor feed gas comprising silicon tetrachloride and a reactor product gas comprising trichlorosilane, the reactor feed gas being within the tubes of the tube bundle and the reactor product gas being within a chamber formed between the tube bundle and the shell.
2. The reactor apparatus as set forth in claim 1 wherein the shell and tube heat exchanger comprises:
an annular baffle having a outer edge, an inner edge and a plurality of peripheral openings formed within the outer edge and the inner edge, wherein the peripheral tubes pass through the peripheral openings; and
a central baffle having a plurality of central openings, wherein the central tubes pass through the central openings.
3. The reactor apparatus as set forth in claim 2 wherein the central baffle has an outer edge and wherein the peripheral tubes pass between the outer edge of the central baffle and the shell.
4. The reactor apparatus as set forth in claim 2 further comprising at least two annular baffles.
5. The reactor apparatus as set forth in claim 2 further comprising at least three annular baffles and wherein no more than two annular baffles are adjacent to one another.
6. The reactor apparatus as set forth in claim 2 further comprising at least two central baffles.
7. The reactor apparatus as set forth in claim 2 further comprising at least three central baffles and wherein no more than two central baffles are adjacent to one another.
8. The reactor apparatus as set forth in claim 2 wherein the sum of annular baffles and central baffles is at least five.
9. The reactor apparatus as set forth in claim 2 further comprising a distribution plate with a plenum formed therein, the plenum being in fluid communication with the peripheral tubes and the central tubes to introduce the reactor feed gas into the peripheral tubes and central tubes.
10. The reactor apparatus as set forth in claim 2 wherein the ratio of the average axial distance between the baffles (D 1 ) and the diameter (D 2 ) of the shell is from about 3:1 to about 1:3.
11. The reactor apparatus as set forth in claim 2 wherein the central tubes pass through the annular baffle inward to the inner edge of the annular baffle.
12. The reactor apparatus as set forth in claim 2 wherein the central baffle has an outer edge and a plurality of flare-out portions that extend to the shell.
13. The reactor apparatus as set forth in claim 2 wherein the ratio of the cross-sectional area defined by the annular baffle to the cross-sectional area defined by the shell is at least about 1:10.
14. The reactor apparatus as set forth in claim 2 wherein the annular baffle has a central opening inward to the inner edge of the annular baffle and wherein the ratio of cross-sectional area of the central baffle to the cross-sectional area of the central opening of the annular baffle is at least about 1:5.
15. The reactor apparatus as set forth in claim 2 wherein the reactor product gas passes through the chamber formed between the tube bundle and the shell, and wherein the central baffle has an outer edge and the reactor product gas passes between the outer edge of the central baffle and the shell and passes inward to the inner edge of the annular baffle.
16. The reactor apparatus as set forth in claim 1 further comprising a first shell and a second shell, the first shell being the shell of the heat exchanger that is in fluid communication with the reaction chamber, the second shell being concentric to the first shell and having a radius greater than the radius of the first shell, the first shell and second shell forming an annular chamber between the first shell and second shell.
17. The reactor apparatus as set forth in claim 16 wherein the reactor product gas passes through the chamber formed between the tube bundle and the shell, and the reactor feed gas passes through the central and peripheral tubes.
18. The reactor apparatus as set forth in claim 1 wherein the reaction chamber abuts the reaction vessel wall.
19. The reactor apparatus as set forth in claim 2 wherein the annular baffle contacts the shell.
20. The reactor apparatus as set forth in claim 1 wherein the heat exchanger includes the terminal flange.
21. The reactor apparatus as set forth in claim 1 wherein the reaction chamber is distinct from the chamber formed between the tube bundle and the shell.
22. The reactor apparatus as set forth in claim 1 wherein the wall of the reaction vessel is distinct from the shell of the shell and tube heat exchanger.
23. The reactor apparatus as set forth in claim 1 wherein the shell and tube heat exchanger further comprises a reactor gas discharge and a product gas inlet, the reactor gas discharge being above the product gas inlet.