Automated air filtration and drying system for waterborne paint and industrial coatings

• US 5,970,625 A
• Filed: 06/24/1997
• Issued: 10/26/1999
• Est. Priority Date: 09/24/1993
• Status: Expired due to Fees

• Current Assignee: Optimum Air Corp
• Original Assignee: Optimum Air Corp
• Inventors: Scheufler, Fred G., Bayard, William H., Scheufler, Richard D.
• Primary Examiner(s): Bennett, Henry
• Assistant Examiner(s): NORMAN, MARC E
• Application Number:
  US08/881,818
• Time in Patent Office: 854 Days
• Field of Search: 34/468, 34/472, 34/474, 34/477, 34/480, 34/666, 118/58, 118/64, 118/66, 118/DIG. 7, 118/326, 427/421, 427/541, 427/372.2
• US Class Current: 34/477
• CPC Class Codes: B01D 46/00 Filters or filtering processes specially modified for separating dispersed particles from gases or vapours filtering elements B01D24/00-B01D35/00; filtering material B01D39/00; their regeneration outside the filters B01D41/00
• CPC Class Codes: B01D 50/00 Combinations of methods or devices for separating particles from gases or vapours
• CPC Class Codes: B01D 53/261 by adsorption
• CPC Class Codes: B01D 53/265 by refrigeration (condensation)
• CPC Class Codes: B05B 14/43 by filtering the air charged with excess material
• CPC Class Codes: B05B 16/60 Ventilation arrangements specially adapted therefor
• CPC Class Codes: B05D 3/002 Pretreatement
• CPC Class Codes: B05D 3/0413 Heating with air
• CPC Class Codes: F26B 21/003 Supply-air or gas filters
• CPC Class Codes: F26B 21/083 by using sorbent or hygroscopic materials, e.g. chemical substances, molecular sieves
• CPC Class Codes: F26B 21/086 by condensing the moisture in the drying medium, which may be recycled, e.g. using a heat pump cycle
• CPC Class Codes: Y02P 70/10 Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working

Abstract

An automated air filtration and drying system including an energy and environmental management system for controlling, monitoring and supervising the operation and performance of the air filtration and drying system, a capture apparatus for capturing and controlling overspray, and a drying/curing control module for rapidly drying a painted article using a continuously filtered and dehumidified flow of recycled air.

Claims

1. A method of using recycled air to dry a product coated with a waterborne coating, said method comprising the steps of:

enclosing said product in a drying booth;

exhausting a contaminated, moist air from said drying booth;

filtering said contaminated, moist air to create a filtered, moist air;

dehumidifying said filtered, moist air to create a filtered, dry air, wherein said dehumidifying step includes the steps of;

cooling said filtered, moist air with an evaporator thereby removing moisture therefrom to create a filtered, cool, dry air;

reheating said filtered, cool, dry air with a reheat coil to create a MN filtered, MN dry air;

returning said filtered, dry air to said drying booth wherein said filtered, dry air can absorb moisture and contaminants from said product coated with a waterborne coating; and

repeating the above steps until said product coated with said waterborne coating is substantially dry.

2. The method of claim 1, wherein said filtering step includes the step of:

passing said contaminated, moist air through at least one dry type filter.

3. The method according to claim 1, further including the step of:

maintaining the air in said drying booth at a temperature in the range of about 45 degrees F. to about 125 degrees F.

4. The method according to claim 1, further including the step of:

maintaining the air in said drying booth at a relative humidity in the range of about 25 to 95 percent.

5. The method according to claim 1, wherein said waterborne coating is a paint.

6. The method according to claim 1, further including the step of:

performing said enclosing, exhausting, filtering, dehumidifying, returning, and repeating steps to dry said product prior to an application of said waterborne coating; and

performing said enclosing, exhausting, filtering, dehumidifying, returning, and repeating steps after coating said product with said waterborne coating until said product is substantially dry.

7. The method according to claim 1, wherein said cooling step includes the step of:

cooling said filtered moist air below its dew point.

8. The method according to claim 1, wherein said cooling step includes the step of:

cooling said filtered moist air, and removing moisture therefrom, using an evaporator.

9. The method according to claim 1, further including the step of:

passing said cooled air over said coated product in said drying booth to remove moisture from the waterborne coating on said coated product.

10. The method according to claim 1, further including the step of:

selectively using a humidifying system to maintain the air in said drying booth at a relative humidity in the range of about 25 to 95 percent.

11. The method according to claim 1, further including the step of:

selectively using a temperature control system to maintain the air in said drying booth at a temperature in the range of about 45 degrees F. to about 125 degrees F.

12. A method of using recycled air to dry a product coated with a waterborne coating, the method comprising the steps of:

enclosing the product in a drying booth;

exhausting a contaminated, moist air from the drying booth;

dehumidifying and filtering the contaminated, moist air to create a filtered, dry air, wherein the dehumidifying and filtering step includes the step of cooling the contaminated, moist air to remove moisture therefrom and create a cooled air;

returning the filtered, dry air to the drying booth wherein the filtered, dry air can absorb moisture from the product coated with a waterborne coating; and

repeating the above steps until the product coated with the waterborne coating is substantially dry.

13. The method according to claim 12, wherein the dehumidifying and filtering step includes the step of:

passing the contaminated, moist air through at least one dry type filter.

14. The method according to claim 12, further including the step of:

maintaining the air in the drying booth at a temperature in the range of about 45 degrees F. to about 125 degrees F.

15. The method according to claim 12, further including the step of:

maintaining the air in the drying booth at a relative humidity in the range of about 25 to 95 percent.

16. The method according to claim 12, wherein the waterborne coating is a paint.

17. The method according to claim 12, further including the step of:

performing the enclosing, exhausting, dehumidifying and filtering, returning, and repeating steps to dry the product prior to an application of the waterborne coating; and

performing the enclosing, exhausting, dehumidifying and filtering, returning, and repeating steps after coating the product with the waterborne coating until the product is substantially dry.

18. The method according to claim 12, wherein the cooling step includes the step of:

cooling the contaminated, moist air below its dew point.

19. The method according to claim 12, wherein the cooling step includes the step of:

cooling the contaminated, moist air, and removing moisture therefrom, using an evaporator.

20. The method according to claim 12, further including the step of:

passing the cooled air over the coated product in the drying booth to remove moisture from the waterborne coating on the coated product.

21. The method according to claim 12, further including the step of:

selectively using a humidifying system to maintain the air in the drying booth at a relative humidity in the range of about 25 to 95 percent.

22. The method according to claim 12, further including the step of:

selectively using a temperature control system to maintain the air in the drying booth at a temperature in the range of about 45 degrees F. to about 125 degrees F.

23. A method of drying a product coated with a waterborne paint, the method comprising the steps of:

enclosing the product in a drying booth;

exhausting a contaminated, moist air from the drying booth;

dehumidifying the contaminated, moist air to create a dry air, wherein the dehumidifying step includes the step of cooling the contaminated, moist air to remove moisture therefrom and create a cooled air;

returning the dry air to the drying booth wherein the dry air can absorb moisture from the product coated with a waterborne paint; and

repeating the above steps until the product coated with a waterborne paint is substantially dry.

24. The method according to claim 23, further comprising the step of:

passing the contaminated, moist air through at least one dry type filter.

25. The method according to claim 23, further including the step of:

maintaining the air in the drying booth at a temperature in the range of about 45 degrees F. to about 125 degrees F.

26. The method according to claim 23, further including the step of:

maintaining the air in the drying booth at a relative humidity in the range of about 25 to 95 percent.

27. The method according to claim 23, further including the step of:

performing the enclosing, exhausting, dehumidifying, returning, and repeating steps to dry the product prior to an application of the waterborne paint; and

performing the enclosing, exhausting, dehumidifying, returning, and repeating steps after painting the product with the waterborne paint until the product is substantially dry.

28. The method according to claim 23, wherein the cooling step includes the step of:

cooling the contaminated, moist air below its dew point.

29. The method according to claim 23, wherein the cooling step includes the step of:

cooling the contaminated, moist air, and removing moisture therefrom, using an evaporator.

30. The method according to claim 23, further including the step of:

passing the dry air over the coated product in the drying booth to remove moisture from the waterborne paint on the coated product.

31. The method according to claim 23, further including the step of:

selectively using a humidifying system to maintain the air in the drying booth at a relative humidity in the range of about 25 to 95 percent.

32. The method according to claim 23, further including the step of:

selectively using a temperature control system to maintain the air in the drying booth at a temperature in the range of about 45 degrees F. to about 125 degrees F.

33. A method of using recycled air to dry a product coated with a waterborne coating, said method comprising the steps of:

enclosing said product in a drying booth;

exhausting a contaminated, moist air from said drying booth;

filtering said contaminated, moist air to create a filtered, moist air;

dehumidifying said filtered, moist air to create a filtered, dry air, wherein said dehumidifying step includes the step of controlling the humidity of said filtered, dry air with a humidifier;

returning said filtered, dry air to said drying booth wherein said filtered, dry air can absorb moisture and contaminants from said product coated with a waterborne coating; and

repeating the above steps until said product coated with said waterborne coating is substantially dry.

34. A method of using recycled air to dry a product coated with a waterborne coating, said method comprising the steps of:

enclosing said product in a drying booth;

exhausting a contaminated, moist air from said drying booth;

filtering said contaminated, moist air to create a filtered, moist air;

dehumidifying said filtered, moist air to create a filtered, dry air, wherein said dehumidifying step includes the step of cooling said filtered moist air to remove moisture;

returning said filtered, dry air to said drying booth wherein said filtered, dry air can absorb moisture and contaminants from said product coated with a waterborne coating; and

repeating the above steps until said product coated with said waterborne coating is substantially dry.