Slurry phase polymerisation process
View Patent ↗A process comprising polymerising in a loop reactor of continuous tubular construction an olefin monomer optionally together with an olefin comonomer in the presence of a polymerisation catalyst in a diluent to produce a slurry comprising solid particulate olefin polymer and the diluent wherein the internal diameter of at least 50% of the total length of the reactor is at least 700 millimeters and the solids concentration in the reactor is at least 20 volume % is disclosed.
1. A process comprising polymerising in a loop reactor of continuous tubular construction an olefin monomer optionally together with an olefin comonomer in the presence of a polymerisation catalyst in a diluent to produce a slurry comprising solid particulate olefin polymer and the diluent wherein the internal diameter of at least 50% of the total length of the reactor is at least 700 millimeters, wherein the solids concentration in the reactor is at least 20 volume % and wherein the Froude number is maintained below 30.
2. A process as claimed in claim 1 wherein the solids concentration in the reactor is in the range 25-35 volume %.
3. A process as claimed in either claim 1 wherein the internal diameter of at least 50% of the total length of the reactor is over 750 millimeters.
4. A process as claimed in claim 1 wherein the internal diameter of at least 70% of the total length of the reactor is over 700 millimeters.
5. A process as claimed in claim 4 wherein the internal diameter of at least 85% of the total length of the reactor is over 700 millimeters.
6. A process as claimed in claim 1 wherein the space time yield is in the range of 0.2 to 0.35 ton/hour/m 3 .
7. A loop reactor of a continuous tubular construction having at least 2 horizontal sections and at least 2 vertical sections wherein the internal diameter of at least 50% of the total length of the reactor is at least 700 millimeters, wherein the ratio of reactor length to internal diameter is less than 250.
8. A loop reactor as claimed in claim 7 wherein the internal diameter of at least 50% of the total length of the reactor is over 750 millimeters.
9. A loop reactor as claimed in claim 7 wherein the internal diameter of at least 70% of the total length of the reactor is at least 700 millimeters.
10. A loop reactor as claimed in claim 7 wherein the internal diameter of at least 85% of the total length of the reactor is at least 700 millimeters.
11. A loop reactor as claimed in claim 7 wherein the reactor size is over 20m 3 .
12. A loop reactor as claimed in claim 11 wherein the reactor size is in the range 100-175m 3 .
13. A process as claimed in claim 1 wherein the polymer produced has a molecular weight of less than 50 k Daltons.
14. A process as claimed in claim 1 wherein the polymer produced has a molecular weight of greater than 150 k Daltons.