JPH0746334Y2 - Mist filter element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a mist used for separating and removing acid mist, oil mist, plasticizer mist, water mist and the like contained in various gases from the gas. Regarding the filter element.

(Prior Art) Conventionally, as this type of mist filter element,
An element in which a filter medium composed of long glass fibers of the same fiber diameter is rolled into a cylindrical shape to form a multi-layer structure and the density is increased as it becomes the inner layer, and a fine glass between the inner and outer perforated cores. There are known elements in which a fiber layer made of fibers or synthetic fibers is sandwiched, but in any case, when mist in gas is captured by the filter medium, the flow of gas causes the large droplets to move inside the filter medium. However, since the filter medium has a single structure with the same fiber diameter, the grown droplets are contained throughout the filter medium, which increases the pressure loss. In addition, there is a problem that the fan power needs to be increased. The particle size of the mist to be captured is 0.1
Since there is a wide range from μ to a large 100 μ, there is the inconvenience that mist having a wide range of particle sizes cannot be efficiently removed with a filter medium having the same fiber diameter.

As a means for solving such inconvenience, for example, the actual development sho 53-
As proposed in Japanese Patent No. 122778, a fine fiber having fine meshes is obtained by compressing a cotton-like fiber assembly, which is made of fine glass fibers and is flexible and highly elastic, to the extent that it does not shrink when immersed in oil. A filter material made of fine fibers is formed, and on both sides of the filter material made of fine fibers, coarse filter material made of coarse fibers made of fibers having a diameter larger than that of the fine glass fibers is laminated in three layers to remove mist. A mist filter element for supplying gas from the outer layer to cause mist in the gas to coagulate and grow in the intermediate layer to form droplets, and to separate and remove the mist droplets in the inner layer, and Japanese Patent Publication Sho 56-35885. As proposed in the publication, the central layer is composed of a fine fiber fleece with pores that does not contain a binder, a support having no binder on both sides of the central layer and having a coarser porosity than the fine fiber fleece. Fiber pretending Gas is supplied from the outer layer, and the mist in the gas is aggregated and grown in the intermediate layer to form droplets, and the mist is formed into droplets in the inner layer. There is known a mist filter element that separates and removes the mist.

(Problems to be solved by the invention) However, in any case, the mist filter element has a coarse outer layer for removing mist having a large particle size, and an intermediate layer having a fine mesh for removing mist having a medium to fine particle size. Are condensed and made into droplets, and the mist that has been made into droplets is separated by the inner layer and is flowed down and removed, but since the middle layer has fine meshes, the mist that has been made into droplets is not flowed down and is clogged. Occurs, which causes a problem such as an increase in pressure loss.

An object of the present invention is to provide a mist filter element that solves the above problems.

(Means for Solving the Problem) The present inventor has conducted extensive studies to achieve the above object, and as a result, the mist filter elements have different fiber layer densities.
It has been found that by adopting a layered structure and using the filter medium with the largest average pore size in the intermediate layer, the drop-down removal of droplets is improved and an increase in pressure loss during filtration of gas containing mist is prevented. .

The mist filter element of the present invention is made based on the above-mentioned findings, and in a mist filter element that separates mist in gas by passing gas through the filter element, the mist filter element and the inner layer are separated from each other. Consists of 3 layers, outer layer and outer layer,
The inner layer has the finest fiber diameter of 3 μm or less and a thickness of 7 to 25 mm.
The outer layer is thicker than the fiber of the inner layer and has a fiber diameter of 3 to 10 μm and a thickness of 20 to 50 mm, and the intermediate layer is 10 to 10 mm thicker than the fiber of the outer layer. It is characterized in that it is formed into a fiber layer having a thickness of 50 μm and a thickness of 10 to 50 mm.

Further, the intermediate layer may be provided with a reinforcing portion on at least one side thereof.

(Operation) The mist having a medium or large particle size in the gas is captured by the outer layer arranged on the supply side of the gas containing the mist to be separated and removed. Next, in the intermediate layer, the mist trapped in the outer layer grows into large droplets while flowing into the mist filter element while moving to the inside of the mist filter element due to the coalescing effect, that is, the gas flow. Further, the inner layer captures fine mist having a particle size.

(Example) The present invention will be described with reference to the drawings.

1 to 3 show an embodiment of the present invention.

In the figure, 1 indicates a mist filter element, and the mist filter element 1 has a fiber diameter of about 3 μm or less,
Glass fiber with a fiber length of 10 to 30 mm and an average pore diameter of 2 to 20
μm, bulk density of 10 to 300 kg / m ³ and inner layer 2 having a thickness of 7 to 25 mm, and glass fibers or synthetic fibers of long fibers having a fiber diameter of 10 to 50 μm, an average pore diameter of 100 to 500 μm, Intermediate layer 3 having a bulk density of 10 to 300 kg / m ³ and a thickness of 10 to 50 mm, a fiber diameter of 3 to 10 μm, and a fiber length of 3 to 20
The glass layer is about ³ mm and has an average pore size of about 20 to 100 μm, a bulk density of about 10 to 300 kg / m ³ , and a thickness of about 20 to 50 mm. The intermediate layer 3 was laminated on the outer side of the layer 2, and the outer layer 4 was laminated on the outer side of the intermediate layer 2 to form an overall tubular shape.

In the figure, 5 is a shape-retaining member of the mist filter element 1 provided with a plurality of perforations 6 disposed inside the inner layer 2.

In this case, the outer layer 4 can capture mist having a medium or large particle size in the gas, and the fiber filter material has a coarser mesh than the inner layer 2, so the amount of mist retained is large and clogging of the filter material is reduced. To do.

Further, the intermediate layer 3 allows the mist captured in the outer layer 4 to grow into large droplets due to the coalescing effect while flowing along the flow of gas to the inner layer of the filter medium and to flow down.

Further, the inner layer can capture mist having a small particle size in the gas, which is not captured by the outer layer 4 and the intermediate layer 3.

Next, specific examples of the present invention will be described together with comparative examples.

Example Inner diameter 25 made of plastic material and provided with a plurality of perforations 6
Glass fiber having a fiber diameter of 1 μm and a fiber length of 10 to 20 mm outside the cylindrical shape retaining member 5 having a diameter of 0 mm, an outer diameter of 267 mm and a length of 1000 mm, an average pore diameter of 8 μm, a bulk density of 35 kg / m ³ , and a thickness of 7 mm. Inner layer 2 consisting
Is laminated on the outer side of the inner layer 2 with a synthetic fiber having a fiber diameter of 45 μm, an average pore diameter of 164 μm, a bulk density of 67 kg / m ³ , and a thickness of 20 mm. Fiber diameter 6μ
m, glass fiber with a fiber length of 5 to 30 mm, average pore diameter 43μ
A mist filter element 1 was produced by laminating an outer layer 4 having a thickness of m, a bulk density of 48 kg / m ³ and a thickness of 20 mm.

The filter pressure loss and the mist trapping efficiency of the produced mist filter element 1 were examined, and the results are shown in the table.

Measurement conditions Pressure loss Water is sprayed to generate water mist, and the flow rate is 6 m ³ / min from the outer layer of the mist filter element 1 to the intermediate layer 3,
The inner layer 2 is filtered, and the water mist treatment amount is 0 g, 5 g, 10 g, 15 g,
The pressure loss per minute at 20 g and 25 g / m ³ was obtained by a differential pressure gauge.

Mist capture efficiency Generates DOP mist with a particle size of 0.3 μm and filters at 20 cm /
The outer layer 4 to the middle layer 3 and the inner layer 2 of the mist filter element 1 were filtered in seconds, the difference in the concentration of DOP mist in the air before and after filtration was measured, and the trapping efficiency was determined by the following formula.

A is the concentration of DOP mist before filtration B is the concentration of DOP mist after filtration Comparative Example 1 Long glass fibers having a fiber diameter of 10 μm were used, and the long glass fibers were thickly applied to the outside of the same cylindrical shape-retaining member as in the above-mentioned Examples. A mist filter element having a single-layer structure was produced by winding it around 70 mm in a spool shape.

Then, the filter pressure loss and the mist capturing efficiency of the mist filter element manufactured by the same method as in the example were measured, and the measurement results are shown in the table.

Comparative Example 2 A filter medium composed of glass fibers having a fiber diameter of 6 μm and a fiber length of 10 to 30 mm, an average pore diameter of 43 μm, a bulk density of 48 kg / m ³ , and a thickness of 50 mm was applied to the outside of the same cylindrical shape-retaining member as in the above examples. Was laminated to prepare a single-layered mist filter element.

Then, the filter pressure loss and the mist capturing efficiency of the mist filter element manufactured by the same method as in the example were measured, and the measurement results are shown in the table.

Comparative Example 3 A filter medium composed of glass fibers having a fiber diameter of 1 μm and a fiber length of 10 to 20 mm, an average pore diameter of 8 μm, a bulk density of 35 kg / m ³ , and a thickness of 50 mm was applied to the outside of the same cylindrical shape-retaining member as in the above examples. Was laminated to prepare a single-layered mist filter element.

Then, the filter pressure loss and the mist capturing efficiency of the mist filter element manufactured by the same method as in the example were measured, and the measurement results are shown in the table.

Comparative Example 4 The inner layer 2 and the outer layer 4 were made of long fibers each having a fiber diameter of 19 μm, an average pore diameter of 73 μm, a bulk density of 160 kg / m ³ , and a thickness of 25 mm, and the intermediate layer 3 was a fiber diameter of 1 μm and a fiber length. 10 to 20 mm
A multi-layer filter medium made of glass fiber having a mean pore size of 8 μm, a bulk density of 35 kg / m ³ and a thickness of 4 mm is used as an inner layer, an intermediate layer, and an outer layer of the same cylindrical shape-retaining member as in the above embodiment. A mist filter element having a three-layer structure was produced by stacking layers in this order.

Then, the filter pressure loss and the mist capturing efficiency of the mist filter element manufactured by the same method as in the example were measured, and the measurement results are shown in the table.

As is clear from the table, the mist filter element of the embodiment of the present invention having a three-layer structure in which the inner layer, the intermediate layer and the outer layer are different from each other, the mist capturing efficiency was extremely high and the pressure loss was low. On the other hand, the mist trapping element of Comparative Example 1 and Comparative Example 4 consisting of a single fiber layer, and the mist filter element of Comparative Example 4 in which the fiber layers of the inner layer and the outer layer are the same even though the three-layer structure is the same as that of the embodiment, Although the pressure did not decrease as much as the left, the pressure loss was high. The mist filter element of Comparative Example 2 had a low pressure loss, but the mist trapping efficiency was extremely low.

Therefore, it was confirmed that the mist filter element of the embodiment of the present invention has less pressure loss and higher mist capturing efficiency than the mist filter elements of Comparative Examples 1, 2, 3, and 4.

4 and 5 show another embodiment of the present invention, in which a plurality of convex reinforcing portions 7 are provided at appropriate positions on the inner surface side of the intermediate layer 3.
Is integrally formed with the intermediate layer 3, and when the intermediate layer 3 is laminated on the outer side of the inner layer 2, the reinforcing portion 7 is brought into contact with the outer surface of the inner layer 2 to form an outer surface of the inner layer 2. The void portion 8 was formed between the intermediate layer 3 and the inner surface thereof.

In this case, the reinforcing portion 7 formed between the outer surface of the inner layer 2 and the inner surface of the intermediate layer 3 allows the fibers of the inner layer 2 and the outer layer 4 to be coarse and dense by the gas pressure when the gas passes. Is prevented, the gas flow is made uniform by the voids 8 formed by the reinforcing portion 7, and the intermediate layer 3 and the inner layer 2
By providing the void portion 8 between them, the mist dripping can be more completely approached by the intermediate layer 3 and the entire mist filter element can be reinforced.

Although the reinforcing portion 7 is formed on the inner surface side of the intermediate layer 3 in the examples shown in FIGS. 4 and 5, even if the reinforcing portion 7 is formed on both inner and outer surfaces of the intermediate layer 3 as shown in FIGS. 6 and 7. Good.

Although the reinforcing portion 7 is formed integrally with the intermediate layer 3 in FIGS. 4 and 5, 6 and 7, the reinforcing portion 7 is formed separately from the intermediate layer. For example, a rib or a porous plate. Alternatively, the reinforcing member may be provided on one side or both sides of the intermediate layer.

(Effect of the Invention) As described above, in the mist filter element of the present invention, the inner layer is formed in the finest fiber diameter of 3 μm or less and the thickness of 7 to 25 mm, and the outer layer is thicker than the fiber of the inner layer. It is formed into a fiber layer having a diameter of 3 to 10 μm and a thickness of 20 to 50 mm, and the intermediate layer is thicker than the fibers of the outer layer and has a fiber diameter of 10 to 50 μm and a thickness of 10
Since it has a three-layer structure with a fiber layer of ~ 50 mm, when the gas containing mist is filtered, the outer layer captures mist with a medium or large particle size in the gas, and then the captured mist is intermediate. The layer grows into droplets so that the droplets can be surely dropped. Furthermore, the inner layer can capture mist with a fine particle size that cannot be captured by the outer layer and the intermediate layer. It is possible to capture the mist in three stages, the mist dripping proceeds in the middle layer of the filter medium of the mist filter element, and the mist in the filter medium can be reduced, so clogging is reduced and pressure loss is reduced. It has an effect that gas containing mist can be efficiently filtered.

Further, by forming a reinforcing portion on at least one surface side of the intermediate layer, it is possible to prevent the fibers of the inner layer and the outer layer from becoming coarse and dense due to gas pressure when the gas passes, and to pass by the void portion formed by the reinforcing portion. This has the effect of making the flow of the generated gas uniform and reinforcing the entire mist filter element.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention. FIG. 1 is a perspective view showing the structure, and FIG.
II-II line sectional view, FIG. 3 is a III-III line sectional view of FIG.
4 and 5 show another embodiment of the present invention.
FIG. 5 is a sectional view similar to FIG. 2, FIG. 5 is a sectional view similar to FIG. 3, FIG. 6 and FIG. 7 are other embodiments, and FIG. Similar sectional view, FIG. 7 is a sectional view similar to FIG. 1 ... Mist filter element 2 ... Inner layer 3 ... Middle layer 4 ... Outer layer 7 ... Reinforcement part

Claims (2)

[Scope of utility model registration request] 1. A mist filter element for separating a mist in a gas by passing a gas through the filter element, wherein the mist filter element is composed of an inner layer, an intermediate layer and an outer layer, and the inner layer is The finest fiber diameter is 3 μm or less and the thickness is 7 to 25 mm, and the outer layer is thicker than the fiber in the inner layer.
m, a mist filter element characterized by being formed into a fiber layer having a thickness of 20 to 50 mm, and the intermediate layer being formed into a fiber layer having a fiber diameter of 10 to 50 μm and a thickness of 10 to 50 mm, which is thicker than the fibers of the outer layer. . 2. The mist filter element according to claim 1, wherein the intermediate layer has a reinforcing portion on at least one surface side.