JPH05184829A - Micro carbon filter - Google Patents

Abstract

PURPOSE:To efficiently and surely filter off the superfine particles in a liq. such as water by controlling the average pore diameter and porosity of a graphite material to be used. CONSTITUTION:A graphite material with the average pore diameter measured by the mercury penetration method controlled to 0.5 to 5mum and the porosity to >=5% is used to constitute the filter. Accordingly, the bacteria such as coli bacteria having 1-3mum size and contained in a liq. such as water and the superfine particles of the sand, clay, iron rust, etc., causing turbidity are effectively and efficiently filtered off by this micro carbon filter, and the desired filtration rate is obtained. The filter is applied to the working oil in addition to water.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a micro carbon filter used in filtration of water such as water supply, filtration of industrial water, and cleaning of working oil.

[0002]

2. Description of the Related Art When a substance contained in water is classified, depending on the size of the substance, a dissolved substance of 1 nm or less, 1 nm to 1 nm
It is roughly divided into colloidal substances of about μm and suspended substances of more than that. Generally, in order to remove suspended solids, static sedimentation or coagulation sedimentation is followed by filtration using a sand layer.

Similarly, colloidal substances are similarly filtered through a sand layer after coagulation and sedimentation. However, although the large suspended solids have good filtration efficiency, it was almost impossible to remove substances such as ultrafine particles of iron rust or the like having a size of about 1 μm or less, or bacteria by the sand layer. Further, although filtration by using a hollow system having holes of about 10 nm has been put into practical use, there is a drawback that the holes are small and the desired filtration weight of water cannot be obtained.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made by paying attention to the above-mentioned various problems, and micro carbon using a graphite material capable of efficiently and surely removing a substance of about 1 μm or less by filtration.・ The challenge is to develop a filter.

[0005]

Means for Solving the Problems In order to solve the above-mentioned problems, the inventors of the present invention studied graphite materials having various physical properties and conducted various studies, and as a result, the average gas measured by mercury porosimetry. By using a graphite material having a pore size of 0.5 μm to 5 μm and a porosity of 5% or more, 1
They have succeeded in the present invention by finding that a substance having a size of about μm or less can be efficiently filtered.

Here, when the average pore diameter is 5 μm or more, 1
The collection efficiency of substances of about μm or less deteriorates,
When the average pore diameter is 0.5 μm or less, the desired filtration flow rate cannot be obtained, and when the porosity is 5% or less, the desired filtration flow rate cannot be obtained.

As is well known, the graphite material is not a material having a single pore diameter but exhibits a substantially normal distribution, but the average pore diameter can be represented as the material quality.

That is, according to the present invention, ultrafine particles in a liquid such as water can be filtered by controlling the average pore diameter and porosity of the graphite material.

[0009]

Example 1 Graphite material having an average pore diameter of 0.3 μm and porosity of 5% Graphite material having an average pore diameter of 3 μm and a porosity of 20% A graphite material having an average pore diameter of 8 μm and a porosity of 40% was used.
A circular filter having a thickness of 6 m / m and a diameter of 50 m / m was prepared. Through this filter, 100 l of a test liquid prepared by adjusting alumina powder having an average particle size of 2.17 μm (particle size distribution is shown in FIG. 1) to 100 ppm was passed under a pressure of 1.0 kg / cm ² . Table 1 shows the remaining amount of alumina powder in the filtrate and the passage time.

[0010]

[Table 1]

[0011]

Example 2 Using the same filter using graphite material as in Example 1, 100 l of water containing about 130 ppm of iron rust was passed through at a pressure of 1.0 kg / cm ² . The results are shown in Table 2.

[0012]

[Table 2]

[0013]

As described above, the micro carbon filter of the present invention is contained in a liquid such as water in an amount of 1 to 3 μm.
Bacteria such as E. coli, sand and clay that cause nigori,
Ultrafine particles such as iron rust can be efficiently filtered, and a desired filtration flow rate can be obtained. In addition, it can be applied not only to water but also as a microfilter for liquids such as machine oil, and the field of application will expand.

[Brief description of drawings]

FIG. 1 is a table showing a particle size distribution of alumina powder having an average particle size of 2.17 μm used in Example 1.

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[Procedure amendment]

[Submission date] February 17, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

Similarly, colloidal substances are similarly filtered through the sand layer after coagulation and sedimentation. However, although large suspended matter has good filtration efficiency, it is almost impossible to remove substances such as ultrafine particles of iron rust or the like having a size of about 1 μm or less and substances such as bacteria by filtration in the sand layer. Although filtration by the use of hollow fiber with 10nm longitudinal holes have been in practical use, the hole there is a small hope drawbacks filtration flow amount can not be obtained in water.

Claims (1)

[Claims] A micro carbon filter for liquids, which is made of a graphite material having an average pore diameter of 0.5 μm to 5 μm measured by a mercury intrusion method and a porosity of 5% or more.