Melt cooler and valving system for an underwater pelletizing process

1. A melt cooler and valving system for an underwater pelletizer, comprising:

a melt cooler that cools a polymeric melt, including a melt cooler inlet line that conveys the melt to the cooler, and a melt cooler outlet line that conveys the cooled melt from the cooler; and

a diverter valve configured to convey the melt to and from the cooler during a cooling mode of operation, to convey the melt around the cooler during a bypass mode of operation, and to drain the melt from the cooler and from the diverter valve during a drain mode of operation,

the diverter valve including a first and a second positionable valve component each (i) having a plurality of sets of flow channels therein and (ii) being independently positionable so as to effect separately and independently the cooling mode of operation, the bypass mode of operation, and the drain mode of operation.

2. The melt cooler and valving system according to claim 1 , wherein the diverter valve includes a hot melt inlet line, a hot melt outlet line to the melt cooler, a hot melt bypass line, a cooled melt inlet line from the melt cooler, a cooled melt outlet line, and a melt drain line.

3. The melt cooler and valving system according to claim 2 , wherein to configure the diverter valve for the cooling mode the first positionable valve component is positioned so as to open the hot melt outlet line to the melt cooler, close the hot melt bypass line, and close the melt drain line, and the second positionable valve component is positioned so as to open the cooled melt inlet line from the melt cooler, thereby providing a melt flow path through the melt cooler and out of the diverter valve through the cooled melt outlet line.

4. The melt cooler and valving system according to claim 2 , wherein to configure the diverter valve for the bypass mode the first positionable valve component is positioned so as to close the hot melt outlet line to the melt cooler and close the melt drain line, and the second positionable valve component is positioned so as to close the cooled melt inlet line from the melt cooler, thereby providing a melt flow path around the melt cooler and out of the diverter valve through the cooled melt outlet line.

5. The melt cooler and valving system according to claim 2 , wherein to configure the diverter valve for the drain mode the first positionable valve component is positioned so as to open the hot melt outlet line to the melt cooler, close the hot melt bypass line, and open the melt drain line, and the second positionable valve component is positioned so as to open the cooled melt inlet line from the melt cooler, thereby providing a melt flow path from the hot melt inlet line and from a first process side of the melt cooler out of the diverter valve through the melt drain line, and providing a melt flow path from a second process side of the melt cooler out of the diverter valve through the cooled melt outlet line.

6. The melt cooler and valving system according to claim 1 , wherein the melt cooler is located in a vertical orientation above the diverter valve.

7. The melt cooler and valving system according to claim 1 , wherein the melt cooler is a double pass, shell and tube heat exchanger.

8. The melt cooler and valving system according to claim 7 , wherein a process side of the heat exchanger includes static fluid mixing elements therein.

9. The melt cooler and valving system according to claim 7 , wherein the heat exchanger has a jacketed top head that is heated by a thermal heat transfer fluid or by an electric heater cartridge.

10. The melt cooler and valving system according to claim 2 , wherein a top portion of the melt cooler has a heated vent configured to release a compressible fluid therefrom and/or to facilitate drainage of the melt from a bottom portion of the cooler.

11. The melt cooler and valving system according to claim 1 , wherein the melt cooler is located beneath the diverter valve in a vertical orientation and includes a melt drain line and a vent configured to release a compressible fluid in a bottom portion thereof, and the diverter valve includes a hot melt inlet line, a hot melt outlet line to the melt cooler, a hot melt bypass line, a cooled melt inlet line from the melt cooler, and a cooled melt outlet line.

12. The melt cooler and valving system according to claim 11 , wherein to configure the diverter valve for the cooling mode the first positionable valve component is positioned so as to open the hot melt outlet line to the melt cooler and close the hot melt bypass line, and the second positionable valve component is positioned so as to open the cooled melt inlet line from the melt cooler, thereby providing a melt flow path through the melt cooler and out of the diverter valve through the cooled melt outlet line.

13. The melt cooler and valving system according to claim 11 , wherein to configure the diverter valve for the bypass mode the first positionable valve component is positioned so as to close the hot melt outlet line to the melt cooler and open the hot melt bypass line, and the second positionable valve component is positioned so as to close the cooled melt inlet line from the melt cooler, thereby providing a melt flow path around the melt cooler and out of the diverter valve through the cooled melt outlet line.

14. The melt cooler and valving system according to claim 1 , wherein the melt cooler is located in a horizontal orientation above the diverter valve.

15. The melt cooler and valving system according to claim 14 , wherein the melt cooler inlet line is located in a top portion of the melt cooler, and the melt cooler outlet line is located in a bottom portion of the melt cooler.

16. The melt cooler and valving system according to claim 14 , wherein the melt cooler inlet line and the melt cooler outlet line are located in opposing portions of the melt cooler in a side-by-side configuration.

17. The melt cooler and valving system according to claim 14 , wherein the melt cooler inlet line is located in a bottom portion of the melt cooler, and the melt cooler outlet line is located in a top portion of the melt cooler.

18. The melt cooler and valving system according to claim 1 , wherein the diverter valve includes a hot melt inlet line, a hot melt outlet line to the melt cooler, a hot melt bypass line, a cooled melt inlet line from the melt cooler, a cooled melt outlet line, and first and second melt drain lines.

19. The melt cooler and valving system according to claim 18 , wherein to configure the diverter valve for the drain mode the first positionable valve component is positioned so as to open the hot melt outlet line to the melt cooler, close the hot melt bypass line, and open the first melt drain line, and the second positionable valve component is positioned so as to open the cooled melt inlet line from the melt cooler and open the second melt drain line, thereby providing a melt flow path from the hot melt inlet line and from a first process side of the melt cooler out of the diverter valve through the first melt drain line, and providing a melt flow path from a second process side of the melt cooler and from the cooled melt outlet line out of the diverter valve through the second melt drain line.

20. The melt cooler and valving system according to claim 2 , wherein the melt cooler is oriented perpendicular to a melt flow path through the diverter valve, and the first positionable valve component is an actuatable bolt having three sets of flow channels therein.

21. A melt cooler valving system for an underwater pelletizer, comprising a diverter valve configured to convey polymeric melt to and from a melt cooler during a cooling mode of operation, to convey the melt around the cooler during a bypass mode of operation, and to drain the melt from the cooler and from the diverter valve during a drain mode of operation,

the diverter valve having a housing with a hot melt inlet line, a first positionable valve component, a hot melt outlet line to the melt cooler, a hot melt bypass line, a cooled melt inlet line from the melt cooler, a second positionable valve component, a cooled melt outlet line, and a melt drain line,

the first and second positionable valve components each (i) having a plurality of sets of flow channels therein and (ii) being independently positionable so as to effect separately and independently the cooling mode of operation, the bypass mode of operation, and the drain mode of operation.

22. The valving system according to claim 21 , wherein the first positionable valve component is an actuatable bolt having three sets of flow channels therein, and the second positionable valve component is an actuatable bolt having two sets of flow channels therein.

23. A method of cooling a polymeric melt for an underwater pelletizer, comprising:

conveying the melt to a diverter valve that conveys the melt to and from a melt cooler during a cooling mode of operation, conveys the melt around the cooler during a bypass mode of operation, and drains the melt from the cooler and from the diverter valve during a drain mode of operation, the diverter valve having a hot melt inlet line, a first positionable valve component, a hot melt outlet line to the melt cooler, a hot melt bypass line, a cooled melt inlet line from the melt cooler, a second positionable valve component, a cooled melt outlet line, and first and second melt drain lines, the first and second positionable valve components each (i) having a plurality of sets of flow channels therein and (ii) being independently positionable so as to effect separately and independently the cooling mode of operation, the bypass mode of operation, and the drain mode of operation;

configuring the diverter valve for the cooling mode by positioning the first positionable valve component so as to close the hot melt bypass line and close the first melt drain line, and positioning the second positionable valve component so as to open the cooled melt inlet line from the melt cooler and close the second melt drain line, thereby conveying the melt through the melt cooler and out of the diverter valve through the cooled melt outlet line;

configuring the diverter valve for the bypass mode by positioning the first positionable valve component so as to close the hot melt outlet line to the melt cooler and close the first melt drain line, and positioning the second positionable valve component so as to close the cooled melt inlet line from the melt cooler and close the second melt drain line, thereby conveying the melt around the melt cooler and out of the diverter valve through the cooled melt outlet line; and

configuring the diverter valve for the drain mode by positioning the first positionable valve component so as to open the hot melt outlet line to the melt cooler, close the hot melt bypass line, and open the first melt drain line, and positioning the second positionable valve component so as to open the cooled melt inlet line from the melt cooler and open the second melt drain line, thereby conveying the melt from the hot melt inlet line and from a first process side of the melt cooler out of the diverter valve through the first melt drain line, and conveying the melt from a second process side of the melt cooler and from the cooled melt outlet line out of the diverter valve through the second melt drain line.

24. A method of cooling a polymeric melt for an underwater pelletizer, comprising:

conveying the melt to a diverter valve that conveys the melt to and from a melt cooler during a cooling mode of operation, conveys the melt around the cooler during a bypass mode of operation, and drains the melt from the cooler and from the diverter valve during a drain mode of operation, the diverter valve having a hot melt inlet line, a first positionable valve component, a hot melt outlet line to the melt cooler, a hot melt bypass line, a cooled melt inlet line from the melt cooler, a second positionable valve component, a cooled melt outlet line, and a melt drain line, the first and second positionable valve components each (i) having a plurality of sets of flow channels therein and (ii) being independently positionable so as to effect separately and independently the cooling mode of operation, the bypass mode of operation, and the drain mode of operation;

configuring the diverter valve for the cooling mode by positioning the first positionable valve component so as to close the hot melt bypass line and close the melt drain line, and positioning the second positionable valve component so as to open the cooled melt inlet line from the melt cooler, thereby conveying the melt through the melt cooler and out of the diverter valve through the cooled melt outlet line;

configuring the diverter valve for the bypass mode by positioning the first positionable valve component so as to close the hot melt outlet line to the melt cooler and the melt drain line, and positioning the second positionable valve component so as to close the cooled melt inlet line from the melt cooler, thereby conveying the melt around the melt cooler and out of the diverter valve through the cooled melt outlet line; and

configuring the diverter valve for the drain mode by positioning the first positionable valve component so as to open the hot melt outlet line to the melt cooler and close the hot melt bypass line, and positioning the second positionable valve component so as to open the cooled melt inlet line from the melt cooler, thereby conveying the melt from the hot melt inlet line and from a first process side of the melt cooler out of the diverter valve through the melt drain line, and conveying the melt from a second process side of the melt cooler out of the diverter valve through the cooled melt outlet line.

25. A heat exchanger and valving system for an underwater pelletizer, comprising:

a heat exchanger that exchanges heat with a polymeric fluid, including an exchanger inlet line that conveys the fluid to the exchanger, and an exchanger outlet line that conveys the fluid from the exchanger; and

a diverter valve configured to convey the fluid to and from the exchanger during a heat exchange mode of operation, to convey the fluid around the exchanger during a bypass mode of operation, and to drain the fluid from the exchanger and from the diverter valve during a drain mode of operation,

the diverter valve including a first and a second positionable valve component each (i) having a plurality of sets of flow channels therein and (ii) being independently positionable so as to effect separately and independently the heat exchange mode of operation, the bypass mode of operation, and the drain mode of operation.

26. The heat exchanger and valving system according to claim 25 , wherein the diverter valve includes a melt inlet line, a melt outlet line to the heat exchanger, a melt bypass line, a heat exchanged melt inlet line from the heat exchanger, a heat exchanged melt outlet line, and a melt drain line.

27. The heat exchanger and valving system according to claim 25 , wherein the heat exchanger is configured to cool or heat the melt.

28. The valving system according to claim 22 , wherein the first and second positionable valve components are each a bolt that is actuated by a fluid controlled cylinder.

29. The valving system according to claim 28 , wherein the fluid controlled cylinder is a hydraulic cylinder or a pneumatic cylinder.

30. The melt cooler and valving system according to claim 1 , wherein the first positionable valve component is an actuatable bolt having three sets of the flow channels therein, and the second positionable valve component is an actuatable bolt having at least two sets of the flow channels therein.

31. The melt cooler and valving system according to claim 30 , wherein the first and second positionable valve components are each a bolt that is actuated by a fluid controlled cylinder.

32. The melt cooler and valving system according to claim 31 , wherein the fluid controlled cylinder is a hydraulic cylinder or a pneumatic cylinder.