US20060116066A1

US20060116066A1 - Method for removing environmental contaminants and a related device

Info

Publication number: US20060116066A1
Application number: US11/113,041
Authority: US
Inventors: Tung-Sheng Shih; Rong-Fung Huang; Cheng-Ping Chang; Da-Toung Tang; Jui-Shu Chou; Tse-Pei Fang; Yih-Shiaw Huang
Original assignee: Institute of Occupational Safety and Health Council of Labor Aff
Current assignee: INSTITUTE OF OCCUPATIONAL SAFETY AND HEALTH COUNCIL OF LABOR AFFAIRS; Institute of Occupational Safety and Health Council of Labor Aff
Priority date: 2004-11-29
Filing date: 2005-04-25
Publication date: 2006-06-01
Also published as: TWI281533B; TW200617331A

Abstract

A method for removing environmental contaminants includes: blowing the environmental contaminants along a predetermined direction with a blower; and extracting the blown environmental contaminants along the predetermined direction with a ventilation device; further characterized in: the placement of a guiding side plates between the blower and the ventilation device for guiding a flow path of air flow; and operating with a low blowing force and a strong vacuum force. The present invention also provides a device for removing environmental contaminants.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to a method for removing environmental contaminants and a related device, and more particularly, to a method and related device for removing environmental contaminants that operates using a low blowing force and a strong vacuum force.
2. Description of the Related Art
For industry, the removing of contaminants is a very important issue. Taking the manufacturing of adhesive tape as an example, in production the adhesive is coated onto PVC film, and then the coated film must be baked at a proper temperature to form the adhesive tape. During the baking process, toluene vapor is generated, which can be toxic for the operator. Even though the factory provides a ventilation system, the concentration of toluene may still be too high.
Therefore, it is desirable to provide a method and related device for removing environmental contaminants to mitigate and/or obviate the aforementioned problems.

SUMMARY OF THE INVENTION

An objective of the present invention is to provide a method for removing environmental contaminants.
Another objective of the present invention is to provide a method for removing environmental contaminants that utilizes a low blowing force and a strong vacuum force.
Another objective of the present invention is to provide a device for removing environmental contaminants.
Another objective of the present invention is to provide a B4 device for removing environmental contaminants.
The method for removing environmental contaminants comprises:
blowing air to entrain environmental contaminants in a predetermined direction with a blower; and
extracting the blown air entrained with environmental contaminants in the predetermined direction with a ventilation device;
the method further characterized by:
placement of two guiding side plates between the blower and the ventilation device, the guiding side plates guiding a flow path of the blown air from the blower to the ventilation device; and
said blowing utilizing a weak blowing force and said extracting utilizing a strong vacuum force.
The above-mentioned contaminants include gaseous contaminants (including gases and vapors), gaseous-like contaminants (such as aerosols, dust, mist, fumes, smoke, fog, etc.), and partially gaseous and gaseous-like contaminants, such as toluene, which is partially vaporized at room temperatures and vaporous at high temperatures.
The blower can be any well known blowing device. The predetermined direction is a predetermined blowing direction of the blower, and thus the blower only blows in predominantly a single direction; generally, the predetermined blowing direction is towards the ventilation device.
The ventilation device can be any well known ventilation device. The ventilation device is placed along the predetermined blowing direction.
However, guiding members may be utilized to change the predetermined blowing direction, and the ventilation device should then be placed along the changed ventilation blowing direction.
The guiding side plates can be any typical guiding side plates, such as rectangular guiding side plates. The two guiding side plates may be parallel, or trapezoidal, i.e. like/\. The guiding side platess may extend in a straight manner, or may be slightly curved, but are preferably straight.
The guiding side plates have a height higher than the blown air, which is better more than 1.2 times higher and is best more than 1.5 times higher.
The low blowing force and the strong vacuum force mean a blowing flow has a velocity lower than a vacuum flow. Generally, an air flow velocity of the blower is 0.1 m/s to 1 m/s, and an air flow velocity of the ventilation device is 5 m/s to 15 m/s. Furthermore, a straight line distance between a vent of the blower and an intake of the ventilation device does not exceed 3 m.
The vacuumed contaminants can be recycled or reprocessed.
The present invention also provides a device for removing environmental contaminants comprises:
a blower for blowing air to entrain the environmental contaminants along a predetermined direction;
a ventilation device for extracting the blown air entrained with the environmental contaminants along the predetermined direction; and
two guiding side plates placed between the blower and the ventilation device for guiding a flow path of the blown air;
wherein the blower is operated utilizing a low blowing force and the ventilation device is operated utilizing a strong vacuum force.
All features are defined in the previous explanation. If it is necessary, a processing device can be added for processing the vacuumed contaminants.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a production line for tape production.
FIG. 2 is a schematic drawing of a prior art local ventilation apparatus placed on a tape coating machine.
FIG. 3 is a schematic drawing of a preferred embodiment of a device for removing environmental contaminants placed on a tape advance route.
FIG. 4 shows average toluene concentrations at different locations measured in Comparative Example 1, Embodiment 1 and Embodiment 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In a preferred embodiment, the prior art method (as a comparative example) and the method of the present invention are both utilized to remove toluene vapor from an adhesive tape manufacture process.

COMPARATIVE EXAMPLE 1

The Prior Art Method

Please refer to FIG. 1. FIG. 1 shows an adhesive tape production line. A tradition local ventilation apparatus (as shown above the rollers in FIG. 2) is placed on a tape coating machine for drawing air upwardly, and the evacuated toluene gas can be introduced into a recycling apparatus for reprocessing. For actual measurement results, the ventilation flow speed is less than 0.5 m/s; the distance between the gas intake and the tape surface is about 80 cm; two hanging sheets are mounted to both sides of the gas intake, and there are no other members for stopping other directional flows.
Tape adhesive is pumped to the tape coating machine from a tank and evenly coated onto a PVC film according to the product standards. Before the coated film is sent into a baking area, toluene contained in the adhesive is vaporized into the atmosphere while traversing a transportation path of about 2 m (the total distance from the tape coating machine to the rollers in FIG. 2).
There is a gate and a window on one side of the production line so that outside air can blow into the factory. The operator stands near the window can feel the breeze. Furthermore, large industrial fans are placed at the beginning of the production line to generate an air flow from the primer coat zone to the surface coat zone (as shown in FIG. 1).
In order to immediately measure toluene concentrations at different locations, seven toluene sensors are placed at seven different predetermined positions, as shown in FIG. 1. The average toluene concentration obtained at each predetermined position is shown in FIG. 4.

Embodiments 1 and 2

These examples are similar to the comparative example 1, but the standard local ventilation apparatus is replaced by the device for removing environmental contaminants of the present invention, as shown in FIG. 3. In FIG. 3, the device for removing environmental contaminants comprises a blower 100, a ventilation device 200, and two guiding side plates 310 and 321. The tape is advanced below the device of the present invention as indicated by the dot line arrow. In the first embodiment, the air flow velocity of the blower is 1 m/s, and the air flow velocity of the ventilation device is 7 m/s. In the second embodiment, the air flow velocity of the blower is 0.7 m/s, and the air flow velocity of the ventilation device is 13 m/s. Similarly, the average toluene concentration obtained at each predetermined position is shown in FIG. 4.
Based upon the data shown in FIG. 4, by utilizing the method and the device of the present invention, the second embodiment obtains much lower average toluene concentrations than the prior art. The control removal efficiency of toluene evaporative emissions is 79% (148 ppm→31 ppm); and certain areas in which operators frequently appear have control removal efficiencies of 84% (82 ppm→13 ppm). The method and the device of the present invention easily reduce the average toluene concentrations down to lower than local legal exposure allowance standards: <PEL-TWA (100 ppm), and even less than international exposure allowance standards: <TLV-TWA (50 ppm).
Although the present invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.

Claims

1. A method for removing environmental contaminants comprising:

blowing air to entrain environmental contaminants in a predetermined direction with a blower; and

extracting the blown air entrained with environmental contaminants in the predetermined direction with a ventilation device;

the method further characterized by:

placement of two guiding side plates between the blower and the ventilation device, the guiding side plates guiding a flow path of the blown air from the blower to the ventilation device; and

said blowing utilizing a weak blowing force and said extracting utilizing a strong vacuum force.

2. The method as claimed in claim 1, wherein the guiding side plates have a height higher than the blown air flow.

3. The method as claimed in claim 2, wherein the guiding side plates have a height that is more than 1.2 times higher than the blown air flow.

4. The method as claimed in claim 3, wherein the guiding side plates have a height that is more than 1.5 times higher than the blown air flow.

5. The method as claimed in claim 1, wherein an air flow velocity of the blower is 0.1 m/s to 1 m/s, and an air flow velocity of the ventilation device is 5 m/s to 15 m/s.

6. The method as claimed in claim 1, wherein a straight line distance between a vent of the blower and an intake of the ventilation device does not exceed 3 m.

7. The method as claimed in claim 5, wherein a straight line distance between a vent of the blower and an intake of the ventilation device does not exceed 3 m.

8. A device for removing environmental contaminants comprising:

a blower for blowing air to entrain the environmental contaminants along a predetermined direction;

a ventilation device for extracting the blown air entrained with the environmental contaminants along the predetermined direction; and

two guiding side plates placed between the blower and the ventilation device for guiding a flow path of the blown air;

wherein the blower is operated utilizing a low blowing force and the ventilation device is operated utilizing a strong vacuum force.

9. The device as claimed in claim 8, wherein the guiding side plates have a height higher than the blown air flow.

10. The device as claimed in claim 9, wherein the guiding side plates have a height that is more than 1.2 times higher than the blown air flow.

11. The device as claimed in claim 10, wherein the guiding side plates have a height that is more than 1.5 times higher than the blown air flow.

12. The device as claimed in claim 8, wherein an air flow velocity of the blower is 0.1 μm/s to 1 m/s, and an air flow velocity of the ventilation device is 5 m/s to 15 m/s.

13. The device as claimed in claim 8, wherein a straight line distance between a vent of the blower and an intake of the ventilation device does not exceed 3 m.

14. The device as claimed in claim 12, wherein a straight line distance between a vent of the blower and an intake of the ventilation device does not exceed 3 m.