JPS6291215A - Filtration process of solution - Google Patents

Abstract

PURPOSE:To absorb impurities out of raw water to the filter medium and arrest, and also carry out biological purification by making the flow speed of raw water comparatively high and varying the speed by filter medium into contracted flow (vena contracta) and enlarged flow in turn. CONSTITUTION:The flux density is varied into numbers of contracted flows (vena contracta) and enlarged flow in turn by the sheet-shaped filter medium 1 carrying square pores uniformly and forming concave 2 and convex 3, up and down and alternatively, and impurities in the solution are caught in the filter medium 1, while filtration is carried out maintaining the fluid pressure. Consequently, impurities in the solution are absorbed to the filter medium 1 and arrested effectively by varying kinetic energy in the fluid. Since no large difference is created between front and rear of the filter medium 1, the filtration resistance is not lowered and a constant filtration for a long time is offered and also bilogical purification is carried out by forming a biological membrane.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a filtration method for clarifying solutions such as water, dilute suspensions, aqueous solutions, and solvents.

[Conventional technology]

Generally, batch or continuous filtration is used to clarify water, dilute suspensions, aqueous solutions, solvents, and the like. The equipment used for filtration also uses various filter media depending on the purpose, whether under normal pressure or pressurized conditions.

On the other hand, filter media can range from those consisting of granular fillings to flat media such as filter cloth, but the principle behind all of them is that the impurities in the solution are captured by filtration. The aim is to trap impurities by passing only the solution through the homogeneous or non-uniform micropores. However, in such a filtration method, the filtration resistance due to the filter medium becomes large, and since the filtration resistance is proportional to the porosity function (1-1)''/ε3, not the porosity ε of the filter medium, clogging easily occurs. When a solution containing such impurities is filtered, it becomes impossible to filter it after a short period of time, and the filter medium must be washed.

In particular, when the relationship between water and biological systems changes, and when a large amount of water is filtered and clarified in a state in which solar insects, sucking worms, and fish appear, the various organic substances mentioned above adhere to the filter medium. It becomes impossible to filter.

[Problem that the invention seeks to solve]

Conventional filtration methods in which the solution passes through the fine pores of a screw material are easily clogged by impurities in the solution, increasing filtration resistance. The problem was that it could not be converted.

[Means for solving problems]

The solution filtration method according to the present invention sequentially changes the flux into a plurality of contracting flows and expanding flows using a filter medium, traps impurities in the fluid in the filter medium, and performs filtration while maintaining the fluid pressure. be.

[For production]

In this invention, since the flux changes into a contracting flow and an expanding flow before and after the filter medium in the direction of movement, impurities in the solution, especially organic substances, are efficiently attached to the filter medium due to changes in kinetic energy in the fluid. captured. In addition, the fluid flow pattern is completely different from normal filter media, which allows fluid to pass through micropores due to pressure differences, and since there is no large pressure difference before and after the filter media, there is no decrease in filtration resistance and it lasts for a long time. Continuous filtration is possible, and the purification effect of living organisms can be exerted through the formation of biofilm.

[Example] FIGS. 1 and 2 are perspective views of filter media used in the practice of this invention. The filter medium (1) in Fig. 1 is a sheet-like material having uniformly square holes, with recesses (
2) and a convex portion (3) are formed. Note that the material may be formed by forming a sheet of water-resistant synthetic resin or synthetic rubber and then thermoforming it, or it may be formed by integral molding. Furthermore, a metal linear member coated with synthetic resin or synthetic rubber may also be used. The shape of the hole may be circular rather than square, and the diameter may be about 0.2 to 20 fins.

In addition, the filter medium (5) in Fig. 2 is a sheet (6) with homogeneous square holes and a corrugated sheet (7) with uniform square holes.
) is formed in such a shape that the contacts are joined together, and the shape and size of the pores are similar to those of the filter medium (1) shown in FIG. 1.

By stacking several filter media (1) or (2) configured as described above, a large amount of living organisms, bacteria, algae, etc., as described above, are collected from the direction of arrow A or arrow B shown in Figures 1 and 2. When you run water that exists in
), the state of passing through the square hole in (5) and exiting into space, then passing through the hole is repeated. In other words,
If the entire flow path is made into a large flow path, the flow pattern will repeat such that when the flux flows through a certain gap, it will become a contracting flow, then an expanding flow, and then a contracting flow. As a result, various organic substances such as algae contained in water easily adhere to the filter media (1) and (5), and the angular pores are significantly larger than the voids of ordinary filter media. So it won't get clogged.

Furthermore, due to the pressure distribution within the stacked filter media (1) and (5), the fluid also flows in the vertical direction, but a similar flow pattern of repeated expansion and contraction is given. Furthermore, due to the size of the square holes, the filtration resistance of the filter media (11, (5)) is negligibly small, and the pressure loss of water can also be ignored. Therefore, the flow velocity increases and the amount of air entrained. Since the number of filter media (11,
(By forming a biofilm on the organic matter attached to the water, water can be efficiently purified by the action of aerobic bacteria.

If water quality deteriorates significantly and dissolved oxygen is low, anaerobic bacteria will work, but since there is no drop in filtration resistance and long-term operation is possible, environmental conditions such as biofilms allow anaerobic bacteria to work. is generated. Furthermore, even if some of the square holes become completely clogged, the fluid pressure is distributed in the vertical direction, so the overall filtration rate does not decrease.

By the way, the filter media (1) and (51) were stored in a small tank-like filtration device, and water from a pond with moderately deteriorated water quality was filtered to 300
In an experiment in which filtration was performed for ~600+ hours, filtered water with a clarity comparable to that of tap water was obtained, and continuous operation for about 4 months or more was possible.

〔Effect of the invention〕

As explained above, in this invention, raw water is made into a relatively large flux, and the flow velocity is changed sequentially into contracting flow and expanding flow, so that impurities in raw water can be easily attached to the filter medium and captured, and biological It has the effect of enabling a purifying effect.

[Brief explanation of drawings]

1 and 2 are perspective views of filter media used in the practice of this invention. In the figure, (1) and (5) are filter media. Patent Applicant: Takara Industries Co., Ltd. + Kuma Hoke, Patent Attorney Yasumoto Minoru Method) 6゜February 25, 1986 Mr. Michibu Uga, Commissioner of the Patent Office 7゜1.
Display of the case 1985 Patent Application No. 229919 2 Name of the invention Solution filtration method 3, person making the amendment Relationship to the case Patent applicant address 3-28-5 Omori Nishi, Ota-ku, Tokyo Name Takara Industries Co., Ltd. Representative: Juhiro, Finance Department Address: Hirasawa Building, 1-13-4 Toranomon, Minato-ku, Tokyo January 28, 1986 (Shipping date) Subject of amendment Details of drawing amendments As shown in the attached sheet

Claims (1)

[Claims] In clarifying filtration of water, dilute suspensions, and aqueous solutions, impurities in the fluid are captured by the filter medium by sequentially changing the flux into a plurality of convergence flows and expansion flows using a filter medium, and the fluid pressure is increased. A method of filtrating a solution while maintaining it.