JPH0330806A - Active carbon filtering by cartridge type filter - Google Patents

Abstract

PURPOSE:To prevent the clogging of element by a method wherein a depth type filter element of 15-30mm depth is used in a cartridge type filter and active carbon suspension is subjected to a definite flow amount filtration under pressure at a specific velocity. CONSTITUTION:There is prepared the active carbon suspension contg. the active carbon powder consisting of 50-60% particles having a size of about 40mum in diameter and having a concn. of 0.1-1.0% and viscosity of 1-5cps. This active carbon suspension is subjected to a definite amount filtration under pressure at a cartridge velocity of 1-400ml/min/1 inch through a depth type filter element of 15-30mm depth. More specifically, the liq. to be filtered is introduced through an inlet opening 4 of a cartridge type active carbon filter device 3 into a housing 5 so as to be filtered from its outside to the inside through the filter element 9 of cartridge depth type and the filtered liq. is discharged from a discharge opening 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method of filtering activated carbon using a cartridge type filter with a flux depending on the amount of activated carbon in a liquid, the type of activated carbon, and the viscosity of the liquid.

[Conventional technology]

In the field of manufacturing fine chemical products such as pharmaceuticals and foods, powdered activated carbon has been widely used for purposes such as decolorization and purification.

Although the use of powdered activated carbon has many advantages such as low process cost and high flexibility, it is necessary to remove the activated carbon after the process is completed.

Therefore, in order to remove activated carbon, a method of removing activated carbon using a filter press or a spackle filter is generally known.

[Problem to be solved by the invention]

However, in the conventional method using a filter press or a subacura filter, the apparatus used therein is large and the operation thereof is usually complicated. Furthermore, in the conventional method, it is necessary to replace the filter paper or wash the filter cloth every time, and in addition, during filtration, it is necessary to perform circulation filtration in advance and form a filter cake on the filter cloth or filter paper, which is very labor-intensive. It was a method.

Furthermore, if coarse filter cloth or paper is used to extend the filter life of the filter cloth or paper, fine particles of activated carbon remain in the filtrate, which places a significant load on the downstream final sterilization filter. It turns out. Therefore, in order to protect the final sterilization filter from such loads, it is usually necessary to install one or two stages of pre-filters between the activated carbon filtration and the final sterilization filter, and add a filtration process using the pre-filters. was there.

Therefore, an object of the present invention is to form an activated carbon cake layer on the surface of the depth layer by using a depth type filter element instead of a filter cloth or filter paper, and to collect activated carbon by this cake layer. It is an object of the present invention to provide an activated carbon filtration method that can prevent clogging and extend the filtration life compared to conventional methods.Furthermore, it is an object of the present invention to dramatically improve filtration efficiency to reduce the amount of residual carbon in the filtrate. Another object of the present invention is to provide an activated carbon filtration method that can significantly reduce the amount of activated carbon, and therefore omit the filtration step using a pre-filter and can be directly connected to the final sterilization filtration step. It is an object of the present invention to provide an activated carbon filtration method that can simplify the activated carbon filtration process and reduce labor, and is therefore highly economical.Furthermore, another object of the present invention is to provide an activated carbon filtration method based on the present invention. An object of the present invention is to provide an activated carbon filtration method that allows the activated carbon filtration device itself to be simplified and downsized.

[Means to solve the problem]

In order to solve the above problems, according to the present invention, a depth type filter element with a filter thickness of 15 to 30 mm is used, and the activated carbon concentration is 0.1%, which contains powdered activated carbon containing 50 to 60% of particles with a particle size of about 40 μm. Activated carbon ws liquid with a viscosity of 1 to 1.0% and a viscosity of 1 to 5 cps,
A method of activated carbon filtration using a cartridge type filter is provided, which is characterized by constant flow filtration under pressure at a flux of 400 s+l/sin/1 inch cartridge.

According to the present invention, the higher the viscosity of the activated carbon suspension, the more preferable it is to perform constant flow filtration with a lower flux, e.g.
Constant flow filtration is preferred with a flux of ml/min/1 inch cartridge.

Furthermore, it is also possible to perform a final constant flow filtration of the filtrate after the activated carbon filtration using a sterilizing microfiltration membrane.

Cartridge type depth type filter elements used in the present invention include polypropylene, nylon 66,
It is preferable to use a structure in which layers of welded polymeric fibers such as polyester are laminated from the outside to the inside so that the filtration accuracy is gradually finer, and the inner layer has a uniform filtration accuracy.

Furthermore, the filter thickness of the filter element is preferably 15 to 30 mm; if it is less than 15 mm, clogging may occur before a cake layer is formed on the surface of the filter element, and 30 III 1
If it is 1 or more, it is unfavorable in terms of economic efficiency.

As described above, according to the present invention, the filter thickness is 15 to 3
Activated carbon concentration 0.1% to 1°0%, viscosity 1 cp, with a depth type filter element of 0 m5, containing powdered activated carbon containing 50 to 60% of particles with a particle size of about 40 μl.
1 to 400 ml of activated carbon suspension of s to 5 cps
Constant flow filtration is performed under pressure at a low flow rate of /min/1 inch cartridge, but if filtration is performed at a higher flow rate, a layer of cake is formed on the surface of the filter element. Fine activated carbon particles reach the depth layer of the filter element and are trapped, causing clogging, which is undesirable and limits the amount of filtrate.

[Effect]

According to the activated carbon filtration method configured as described above based on the present invention, the activated carbon suspension is filtered at a sufficiently low flux, so that the activated carbon cake layer is filtered through the filter element without going through an extra circulation filtration step. Since the activated carbon formed on the surface and contained therein is collected in this cake layer, it rarely reaches the depth layer and therefore does not cause clogging of the depth layer.

Further, the activated carbon contained therein can be sufficiently removed only by the filtration step according to the present invention, and there is no need to use a pre-filter.

〔Example〕

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of an activated carbon filtration device using the activated carbon filtration method according to the present invention. A liquid to be filtered containing activated carbon is sent from a tank 1 to a cartridge type activated carbon filtration device 3 by a liquid sending pump 2. The liquid to be filtered is introduced into the housing 5 through an inlet 4 provided at the top of the cartridge-type activated carbon filtration device 3, and is liquid-tightly fixed to the housing head 8 with a bolt 7 via a gasket 6 at the center of the device. The cartridge-type depth type filter element 9 allows the filter element 9 to be
The filtrate is discharged from the discharge port 10. Furthermore, the filtrate is filtered and sterilized using a precision filtration membrane device 11 as necessary.
sent to.

FIG. 2 shows another embodiment of an activated carbon filtration device using the activated carbon filtration method according to the present invention. In this embodiment, both the inlet 10' and the outlet 11' are arranged in the upper part of the housing, so that the housing 5'
Although the position of the filter element 9' and the mounting direction of the filter element 9' are different from those of the embodiment shown in FIG. 1, the operation and effect are essentially the same as those of the embodiment shown in FIG. Therefore, in the following, the present invention will be explained based on the embodiment shown in FIG.

Activated carbon contained in the liquid to be filtered introduced into the housing 5 is generally captured on the surface of the filter element 9 and forms a cake layer on the surface, and some of the fine activated carbon particles are formed as activated carbon. The activated carbon is filtered by being collected in the cake layer.

At the end of filtration, the filtered activated carbon can be easily removed by removing the housing 5 from the housing head 8. At that time, by blowing compressed air from the drain outlet provided at the upper or lower part of the housing 5,
The residual fluid in the housing 5 is removed from the filter element 9 by
It is also possible to increase the recovery rate of the fluid by discharging it to the next side (inside). In addition, compared to the conventional method, there are fewer equipment parts (and the cleaning work is also easier because most of the complicated attachment/detachment work can be avoided).

When performing activated carbon filtration using the cartridge type depth type filter element 9 in this way, if the flux for filtration is too high, a cake layer of activated carbon will not be formed and the activated carbon will reach the depth layer. The filter element 9 will become clogged, reducing the efficiency of the filter. However, when performing filtration at a predetermined sufficiently low flux according to the present invention, it is possible to perform filtration until the primary side (outside) of the housing 5 is filled with activated carbon captured by the filter element 9. become.

The graphs shown in FIGS. 3 to 6 are obtained by suspending Shirasagi P, Shirasagi RA, special Shirasagi, and purified Shirasagi (manufactured by Takeda Pharmaceutical Company Limited) in water, and then filtering this activated carbon-containing filtrate until the primary volume is A 1-inch cartridge with a Ball Profile@YOO5J filter installed in a 90 ml housing provides constant flow filtration at various fluxes with a pressure drop of 1.5-2.0 cgf/am at the end. ”The total amount of activated carbon filtered is compared.

From the above results, according to the present invention, the activated carbon concentration is 0.1%.
For activated carbon suspensions with a viscosity of 1 cps to 1.0%, powdered activated carbon containing 50 to 60% of particles with a particle size of about 40 μm, such as Shiro 3IA manufactured by Shikinichi Yakuhin Kogyo Co., Ltd., and special Shirasagi, was used. In the case of refined Shirasagi, the flux is 1 to 200 1/min/1 inch cartrifuge, and in the case of refined Shirasagi, the flux is 1 to 400 m1/lll1n/1 Ishichi Totorifuji, and in the case of Shirasagi P, 1 ~300m+1/+
It has been found that by performing filtration with a flux of in/1 inch cartridge, an activated carbon cake layer is sufficiently formed on the surface of the depth layer, and the object of the present invention can be achieved.

In addition, the graphs shown in Figures 7 and 8 show the results of experiments similar to those shown in Figures 3 to 6 using Shirasagi P at a viscosity of 2 cP.
The results are shown using solutions of s to 5 cPs, respectively.

This result shows that although the filtration efficiency is slightly reduced when the viscosity of the solution is high, the objective can be achieved by performing constant flow filtration at a sufficiently low flux based on the present invention. That is, the viscosity of the activated carbon suspension is 2 cp
In the case of s to 5 cps, for example, in the case of Shirasagi P, an activated carbon cake layer is formed on the surface of the depth layer by filtration with a flux of 1 to 100 m1/+in/1 season, and the activated carbon contained is Well filtered.

Further, as described above, according to the present invention, one of the housings 5
It is possible to filter activated carbon until the next side (outside) is filled with activated carbon, so when designing the device, the inner volume of the primary side (outside) of the housing 5 should be used for the amount of activated carbon used for one filtration. The volume must be greater than the dry mass multiplied by its bulk density.

Table 1 shows the relationship between the primary side volume of the housing 5 and the amount of filterable activated carbon. In this example, activated carbon suspension 35g/if
According to the present invention, the liquid to be filtrated can be filtered at a sufficiently low flux, that is, 60 (ml/sin/1 inch·
Constant flow filtration was performed using a cartridge cartridge.

Table 1: Changes in the total amount of activated carbon filtered depending on the volume of the primary side of the housing. Here, the amount of activated carbon filtered per unit volume of the primary side of the housing = total filtration amount x 35 g/If ÷ the volume of the primary side of the housing.

As is clear from Table 1, as the primary volume of the housing increases, the amount of activated carbon that can be filtered also increases.
The total filtration amount is the same value for the primary volume of the housing. It was also observed that all the housings were filled with activated carbon.

Furthermore, according to the present invention, the filtrate after activated carbon filtration can be subjected to final filtration directly through a sterilizing microfiltration membrane without going through a filtration step using a pre-filter. According to the method, the activated carbon filtration efficiency has been significantly improved compared to the conventional method, so even without the use of a pre-filter, the pressure loss applied to the sterilization microfiltration membrane hardly increases, and therefore the sterilization microfiltration membrane is under load. There are almost no such things.

Table 2 shows that the filter element 9 is a Pall Profile YOO5J filter, which is used to filter an activated carbon suspension, and the filtrate is widely used as a final filter for sterilization. , 2μs abs,) when constant flow filtration is performed,
A change in the load of the NR filter is shown.

From the above results, it can be seen that even after long-term filtration, the pressure loss of the NR filter hardly increases, and almost no load is applied to the NR filter. Therefore, it can be seen that according to the filtration method according to the present invention, there is no need to undergo a filtration step using a pre-filter before filtration using a final sterilization filter.

(Effects) As described above, according to the present invention, since the activated carbon suspension is filtered by the cartridge type depth type filter element at a sufficiently low flux, the activated carbon suspension can be filtered without going through a circulation filtration step.
An activated carbon cake layer is formed on the surface of the depth layer, and most of the activated carbon contained is collected in this cake layer and does not reach the depth layer, so compared to conventional filtration devices, the filter element is less likely to be clogged and the filtration life is reduced. It is possible to extend it dramatically.

Furthermore, according to the present invention, the amount of residual activated carbon in the filtrate is very small compared to conventional ones, so the filtration process using a pre-filter, which was an essential step in the conventional activated carbon filtration process, can be omitted. The filtrate can be directly filtered through a filtration membrane for final sterilization. Therefore, according to the present invention, the activated carbon filtration step can be simplified and the labor required can be reduced. Furthermore, since the present invention is a cartridge type, the filter element can be easily installed and replaced, which simplifies the manufacturing and maintenance of the device using the present invention, and is therefore extremely economical compared to conventional methods. It's a method.

[Brief explanation of drawings]

1 is a schematic diagram of an activated carbon filtration system using the activated carbon filtration method according to the present invention; FIG. 2 is a schematic diagram of another embodiment of the filtration device of the system shown in FIG. 1; 3 to 6 are graphs showing a comparison of the total amount of filtered activated carbon when activated carbon suspensions in which different activated carbons are suspended are filtered according to the present invention. Figure 3 shows the results using Shirasagi P; Figure 4 shows the results using Shirasagi A; Figure 5 shows the results using the characteristic Shirasagi; Figure 6 shows the results using refined Shirasagi; and Figure 7 and FIG. 8 are graphs showing the results of experiments similar to those shown in FIGS. 3 to 6 using white yItP, respectively. Figure 8 shows the case where a solution with a viscosity of 5 cPs is used. DESCRIPTION OF SYMBOLS 1...tank, 2...liquid pump, 3...cartridge type activated carbon filtration device, 4...inlet, 5...housing, 6...gasket, 7...bolt, 8・
...housing head, 9...filter element,

Claims (3)

[Claims] (1) A depth type filter element with a filter thickness of 15 to 30 mm is used to remove particles with a particle size of about 40 μm.
Activated carbon concentration 0.1 containing powdered activated carbon containing 0-60%
% to 1.0% and a viscosity of 1 cps to 5 cps by a cartridge type filter, characterized in that an activated carbon suspension with a viscosity of 1 cps to 5 cps is filtered at a constant flow rate under pressure at a flux of 1 to 400 ml/min/1 inch cartridge. Activated carbon filtration method. (2) The viscosity of the activated carbon suspension is 2 cps to 5 cps.
2. The activated carbon filtration method according to claim 1, wherein the constant flow rate filtration is performed at a flux of 1 to 100 ml/min/1 inch cartridge. (3) The activated carbon filtration method according to claim 1 or 2, further comprising the step of final constant flow filtration of the filtrate after the activated carbon filtration through a sterilizing microfiltration membrane.