1. A process for converting silicon tetrachloride (STC) to trichlorosilane (TCS), comprising contacting a feed gas comprising STC and H2 with a catalyst in a converter under non-equilibrium operating conditions to provide a supra-equilibrium level of STC conversion to TCS.
2. The process of claim 1, where the catalyst is a metal catalyst.
3. The process of claim 2 where the metal catalyst comprises metal silicides, including without limitation chrome silicide, nickel silicide, and iron silicide.
4. The process of claim 2 wherein the metal catalyst is formed within the converter.
5. The process of claim 4 wherein the converter is charged with a self-supporting metal support, and the surface of the support is at least partially converted to metal catalyst.
6. The process of claim 5 wherein the converter is charged with a metal support, and the entirety of the metal support is converted to metal catalyst, the metal catalyst having sufficient mechanical integrity to maintain its morphology during operation of the converter.
7. The process of claim 6 wherein the process is conducted at a temperature of less than 700\xb0 C.
8. The process of claim 6 wherein the process is conducted at a temperature within the range of 400-600\xb0 C.
9. The process of claim 6 wherein a hold-up time of the feed gas in the converter ranges from 0.1 second to 30 seconds.
10. The process of claim 9 wherein the hold-up time of the feed gas in the converter is 1-5 seconds.
11. The process of claim 1 wherein the pressure in the converter is in the range of from 0.5 atmospheres absolute to 20 atmospheres absolute.
12. The process of claim 11 where the pressure in the converter is in the range of 2 to 10 atmospheres absolute.
13. The process of claim 1 wherein the feed gas comprises H2 and STC at a H2:STC molar ratio in the range of 1:1 to 5:1.
14. The process of claim 1 wherein the feed gas further comprises HCl.
15. The process of claim 1 wherein the supra-equilibrium level of STC conversion to TCS is at least 5% greater than an equilibrium level of STC conversion to TCS under otherwise identical reaction conditions.
16. The process of claim 1 where incoming STC is mixed with H2 and heated to within a few degrees centigrade of the exit temperature of the catalytic converter in a heat interchanger to provide pre-heated gases; these pre-heated gases are then heated to a few degrees above the exit temperature of the catalytic converter in a supplemental heater to provide hot gases; the supplemental heater is heated by means selected from direct fired gases and electrical heaters; the hot gases are fed to the catalytic converter where a reaction to form gaseous products comprising TCS and HCl occurs; the hot gases exiting the catalytic converter are used to preheat incoming STC and H2 vapor in the heat interchanger; cooled product gases exiting the heat interchanger are then separated into constituent parts (e.g., TCS, HCl, and STC) for reuse in a polysilicon plant; and STC separated from the catalytic converter off-gas is recycled back to the catalytic converter system until completely converted to TCS.
17. A system comprising a converter having catalyst therein, a feedstock inlet, a product outlet, a monitoring means to measure a concentration of STC in the feedstock, a monitoring means to measure a concentration of TCS in the product, a heating mechanism to maintain the converter within a desired temperature range, and a flow rate mechanism to maintain a desired holdup time of the feedstock within the reactor.
18. The system of claim 17 further comprising a feedback loop, whereby the measurements of STC and TCS concentrations are used to calculate an actual conversion of STC to TCS, and this conversion is compared to an equilibrium conversion for an operating temperature of the converter, and when the actual conversion is not within a pre-determined range or is below a pre-determined value in excess of the equilibrium conversion, then the system makes automatic adjustments to an operating condition parameter of the converter to achieve a conversion of STC to TCS that meets the pre-determined value in excess of the equilibrium conversion.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A method for downloading data from an auto-storage database, allowing a server to perform one-time data retrieval for transmitting data to terminal devices that request for data downloading; the method comprising the steps of:
(1) submitting a connection request via a terminal device to the server;
(2) determining via the server if to accept the connection request from the terminal device; wherein if the request is accepted, step (3) is proceeded; or else, the step (2) is returned;
(3) storing an IP (Internet protocol) address of the terminal device that submits the connection request via the server into an IP address temporary storage area;
(4) starting timing via the server and determining if counted time reaches a preset time value of data retrieval that is pre-stored in the server; wherein if the preset time value is reached, step (5) is proceeded; or else, the step (4) is returned;
(5) executing one-time data retrieval via the server for retrieving data from a database, and transmitting the retrieved data to the terminal device whose IP address is stored in the IP address temporary storage area; and
(6) requesting via the terminal device for terminating connection to the server upon receiving the retrieved data, allowing the server to stop transmitting data to the terminal device.
2. The method of claim 1, wherein in the step (1), the terminal device submits the connection request to the server through the use of transmission control protocol (TCP).
3. The method of claim 1, wherein in the step (5), the server transmits the retrieved data to the terminal device through the use of user datagram protocol (UDP).
4. The method of claim 1, wherein in the step (6), the terminal device requests for terminating the connection to the server through the use of TCP.
5. The method of claim 1, wherein the database is established in an auto-controls device, for storing data generated during operation of the auto-control device.
6. The method of claim 1, wherein the method for downloading data from an auto-storage database is applicable to a data display system.
7. A system for downloading data from an auto-storage database, comprising:
at least a terminal device for allowing a client to input a connection request and outputting data to the client, the terminal device being provided with a unique IP (Internet protocol) address;
an auto-control device having a database for storing data generated during operation of the auto-control device; and
a server including an IP address temporary storage area, a timing module, a retrieving module and a downloading module, wherein, when the server receives the connection request from the terminal device, it stores the IP address of the terminal device into the IP address temporary storage area, and prompts the timing module to start timing, so as to determine if counted time reaches a preset time value of data retrieval that is pre-stored in the server; if the preset time value is reached, the retrieving module retrieves data from the database of the auto-control device; then, the downloading module transmits the retrieved data to the terminal device whose IP address is stored in the IP address temporary storage area; and the terminal device displays the retrieved data and requests for terminating connection to the server.
8. The system of claim 7, wherein the terminal device submits the connection request to the server through the use of transmission control protocol (TCP).
9. The system of claim 7, wherein upon retrieving data from the database, the server transmits the retrieved data to the terminal device through the use of user datagram protocol (UDP).
10. The system of claim 7, wherein upon receiving the retrieved data from the server, the terminal device requests for terminating the connection to the server through the use of TCP.
11. The system of claim 7, wherein the system for downloading data from an auto-storage database is applicable to a data display system.