Loop reactor for emulsion polymerisation

1. A polymerisation reactor comprising one or more circulation loops with one or more inlets for raw material, one or more outlets, and a circulation pump for circulating a reactor charge within the circulation loop, wherein a by-pass line by-passing the circulation pump connects a point of the loop upstream with a point of the loop downstream, both points being provided with a three-way valve, to form a short loop comprising the pump and a cleaning solvent inlet and a cleaning solvent discharge.

2. The reactor according to claim 1 , wherein at least a part of the short loop and/or the by-pass line is provided with jackets connected to a heating medium source.

3. The reactor according to claim 2 , wherein the heating medium source is heated water.

4. The reactor according to claim 1 , wherein the circulation pump is a positive displacement pump or a centrifugal pump.

5. The reactor according to claim 2 , wherein the circulation pump is a positive displacement pump or a centrifugal pump.

6. A method of cleaning a section of a loop reactor comprising a circulating pump for circulating a reactor charge within said loop, wherein the section is isolated from the circulation loop by three-way valves connecting the section to a by-pass line to form a short circuit via the pump, the method comprising: letting solvent into the short-circuited section via a solvent inlet in the short-circuited section; and circulating the solvent through the short-circuited section one or more times and subsequently draining off the solvent via a solvent discharge outlet.

7. The method according to claim 6 , further comprising subsequently actuating the two three-way valves to close off the by-pass line and to connect the short-circuited section to the other part of the circulation loop.

8. The method according to claim 6 , wherein at least a part of the by-pass line and/or the short-circuited section is heated by a heating medium flowing through jackets.

9. The method according to claim 6 , wherein during circulation of the solvent, a small bleed of solvent is continuously pumped into the short-circuited section, while at the same rate used solvent continuously overflows via an outlet to a container.

10. The method according to claim 7 , wherein at least a part of the by-pass line and/or the short-circuited section is heated by a heating medium flowing through jackets.

11. The method according to claim 7 , wherein during circulation of the solvent, a small bleed of solvent is continuously pumped into the short-circuited section, while at the same rate used solvent continuously overflows via an outlet to a container.

12. The method according to claim 8 , wherein during circulation of the solvent, a small bleed of solvent is continuously pumped into the short-circuited section, while at the same rate used solvent continuously overflows via an outlet to a container.

13. The method according to claim 10 , wherein during circulation of the solvent, a small bleed of solvent is continuously pumped into the short-circuited section, while at the same rate used solvent continuously overflows via an outlet to a container.

14. The method according to claim 8 , wherein the heating medium is heated water.

15. The method according to claim 10 , wherein the heating medium is heated water.

16. The method according to claim 6 , wherein the solvent is circulated for about 15 to 45 minutes.

17. The method according to claim 7 , wherein the solvent is circulated for about 15 to 45 minutes.

18. The method according to claim 8 , wherein the solvent is circulated for about 15 to 45 minutes.

19. The method according to claim 9 , wherein the solvent is circulated for about 15 to 45 minutes.

20. The method according to claim 13 , wherein the solvent is circulated for about 15 to 45 minutes.