System and process for production of polyvinyl chloride

Abstract

A system configured to produce polyvinyl chloride that includes a high shear mixing device comprising at least one rotor/stator set and configured to produce a polymerization mixture by high shear mixing a vinyl chloride solution with an initiator solution, wherein the polymerization mixture comprises an emulsion of droplets; a pump in fluid communication with an inlet of said high shear mixing device; and a vessel in fluid communication with an outlet of said high shear mixing device and configured for to maintain a predetermined pressure and temperature on the polymerization mixture, wherein the vessel comprises an outlet for a product comprising polyvinyl chloride and unconverted vinyl chloride and a vent gas outlet for at least one gas selected from the group consisting of gaseous vinyl chloride, volatile reaction products, and combinations thereof.

1 . A system configured to produce polyvinyl chloride, the system comprising:
 a high shear mixing device comprising at least one rotor/stator set and configured to produce a polymerization mixture by high shear mixing a vinyl chloride solution with an initiator solution, wherein the polymerization mixture comprises an emulsion of droplets;   a pump in fluid communication with an inlet of said high shear mixing device via a high shear device inlet line; and   a vessel in fluid communication with an outlet of said high shear mixing device and configured for to maintain a predetermined pressure and temperature on the polymerization mixture, wherein the vessel comprises an outlet for a product comprising polyvinyl chloride and unconverted vinyl chloride and a vent gas outlet for at least one gas selected from the group consisting of gaseous vinyl chloride, volatile reaction products, and combinations thereof, and wherein at least a portion of the polymerization mixture within the high shear mixing device reacts to form polyvinyl chloride.   
     
     
         2 . The system of  claim 1 , wherein the high shear device is configured to produce droplets in the emulsion with a mean diameter of less than 5 μm. 
     
     
         3 . The system of  claim 1 , wherein the high shear mixing device is configured to produce a tip speed of the at least one rotor of at least 20.3 m/s (4000 ft/min). 
     
     
         4 . The system of  claim 1  comprising a second high shear mixing device operably connected with the high shear device. 
     
     
         5 . The system of  claim 1 , wherein the rotor/stator set comprises a shear gap disposed therebetween, wherein the shear gap comprises a width in the range of about 0.025 mm to about 10 mm, and wherein the rotor/stator each comprise at least one grooved surface. 
     
     
         6 . The system of  claim 1 , wherein the high shear mixing device comprises at least two rotor/stator sets. 
     
     
         7 . The system of  claim 6 , wherein the shear rate provided by a first rotor/stator set of the at least two rotor/stator sets is different from that of a second rotor/stator set. 
     
     
         8 . The system of  claim 1 , wherein said polymerization mixture is subjected to a temperature in the range of about 20° C. to about 230° C. in the vessel. 
     
     
         9 . The system of  claim 1  further comprising a processing device in fluid communication with the vessel, wherein the processing device is configured to reduce the content of unconverted vinyl chloride in the product. 
     
     
         10 . The system of  claim 9 , wherein the processing device comprises a stripper configured to strip unconverted vinyl chloride from the product. 
     
     
         11 . A system configured to produce polyvinyl chloride, the system comprising:
 a high shear mixing device comprising at least one rotor/stator set and configured to produce a polymerization mixture by high shear mixing a vinyl chloride solution with an initiator solution, wherein the polymerization mixture comprises an emulsion of droplets, and wherein said high shear mixing device is configured to produce a shear rate in the range of at least 20,000 s −1 ;   a pump in fluid communication with an inlet of said high shear mixing device via a high shear device inlet line, wherein the pump is fed via a pump inlet line;   a vessel in fluid communication with an outlet of said high shear mixing device, wherein the vessel comprises a vessel outlet for a product comprising polyvinyl chloride and unconverted vinyl chloride and a vent gas outlet for at least one gas selected from the group consisting of gaseous vinyl chloride, volatile reaction products, and combinations thereof;   a processing device positioned downstream of the vessel and configured to reduce the content of unconverted vinyl chloride in the product; and   a recycle line fluidly connecting the processing device with the high shear device, whereby unconverted vinyl chloride may be recycled to the high shear device.   
     
     
         12 . The system of  claim 11 , wherein the high shear mixing device is configured to produce droplets in the emulsion with a mean diameter of less than 5 nm. 
     
     
         13 . The system of  claim 12 , wherein the high shear mixing device is configured to produce a tip speed of the at least one rotor of at least 20.3 m/s (4000 ft/min). 
     
     
         14 . The system of  claim 11  comprising a second high shear mixing device operably connected with the high shear device. 
     
     
         15 . The system of  claim 11 , wherein the rotor/stator set comprises a shear gap disposed therebetween, wherein the shear gap comprises a width in the range of about 0.025 mm to about 10 mm, and wherein the rotor/stator each comprise at least one grooved surface. 
     
     
         16 . The system of  claim 15 , wherein the high shear mixing device comprises at least two rotor/stator sets. 
     
     
         17 . The system of  claim 16 , wherein the shear rate provided by a first rotor/stator set of the at least two rotor/stator sets is different from that of a second rotor/stator set. 
     
     
         18 . The system of  claim 17 , wherein said polymerization mixture is subjected to a temperature in the range of about 20° C. to about 230° C. in the vessel.