RU2136348C1 - Module-type filter element - Google Patents

Abstract

FIELD: cleaning hydrocarbon liquids; chemical, oil refining industry, automotive industry and other industries. SUBSTANCE: capacity and service life of filter element are increased because disks of filter element are stacked. Filter element has rigid cylindrical perforated skeleton with elastic disk of various diameters fitted on it; filter element is also provided with cover for pressing the disks' each stack includes center disk whose diameter is equal to outer diameter of filter element; other disks are mounted on either side from center disk in decreasing order of diameter forming two symmetrical pyramids with central disk used as their common base. After pressing, each pair of disks of similar diameter which are mounted symmetrically relative to central disk form their stage of filtration together with disks having diameter more than diameter of this pair. Degree of compression of filter material in stages increases in way of outer radius to inner one and sizes of pores reduce respectively. EFFECT: smooth reduction of sizes of pores due to multistage compression; smooth distribution of contamination over entire filtering volume; in creased capacity and service life. 2 dwg, 1 tbl

Description

 The invention relates to the field of purification of hydrocarbon liquids and can be used in the chemical, oil refining, automotive and other industries.

 Known filter element of the volume type, consisting of a perforated tubular frame, covers and filter packing, which is a set of disks made of a deformable porous filter material and conical gaskets (a. S. N 1153947). Gaskets are arranged in pairs with the tops of the cones towards each other. The filter disks are crimped by gaskets, as a result of which the deformation of the disks provides the porosity changing in the direction of the filtered fluid flow. Disks compressed by gaskets on the side of the base of the cones have minimal porosity at the entrance, which creates higher hydraulic resistance at the entrance than disks compressed from the side of the tops of the cones. For this reason, the main fluid flow passes through the disks, compressed from the tops of the cones, and the porosity in these disks decreases in the direction of the filtered fluid flow, which provides selective retention of contaminants inside the volume of these disks. The minimum porosity at the entrance to the disks, compressed from the base of the cones, is also the reason for the localization of contaminants on their outer surface, which further prevents the passage of fluid through these disks. Thus, the part of the volume of filter material that falls on the disks compressed from the base of the cones does not participate in the process of delaying pollution, as a result, the dirt capacity and resource of the filter element are reduced.

 Another volumetric filter element (a.s. N 1804887) is known, which consists of a perforated tubular frame, covers and filter packing of disks of larger and smaller diameters, made of a deformable porous filter material, dialed alternately and compressed in the axial direction until large disks contact each other . In general, this design can be considered as two independent coaxially located filtration steps. The first stage has a higher porosity and ensures the retention of large particles of contaminants, the second stage due to the deformation of small disks during compression has a lower porosity and provides a delay of small particles. The disadvantage of such a filter element is that particles of contaminants having a size that allows them to freely pass through the first stage, but larger than the pores at the entrance to the second stage, are localized at the boundary of the steps and block the pores at the entrance to the second stage. As a result, the volume of the filter material is not completely used to delay pollution, which leads to a decrease in dirt capacity and resource.

 The objective of the invention is the creation of such a porous structure of the filter packing, which will avoid the localization of contaminants and ensure uniform loading of pores of the filter material throughout the volume of the filter element, and therefore, increase the dirt capacity and resource while maintaining the required cleaning quality.

где d_н - наружный диаметр фильтроэлемента, Δ₀ - толщина диска в необжатом состоянии, i - порядковый номер диска, начиная со второго, d_i = d_н, при условии d_i > d_в, d_в - внутренний диаметр фильтроэлемента, а количество пакетов в фильтроэлементе N_n по формуле:

где H - высота фильтроэлемента, k - количество дисков в одной пирамиде, включая центральный диск, n - степень обжатия фильтроматериала на выходе фильтроэлемента, которая определяет номинальную тонкость фильтрации d_0,95.This object is achieved in that a volumetric filter element containing a rigid cylindrical perforated frame, elastic disks of various diameters and end caps for compressing disks located thereon, filter element disks are packaged, each of which includes a central disk with an outer diameter equal to the diameter of the filter element , and other disks installed on both sides of it in decreasing order of diameters, forming two symmetrical pyramids with a common base from the central disk, d Disk sizes are determined by the formula:

where d _n is the outer diameter of the filter element, Δ ₀ is the thickness of the disk in an uncompressed state, i is the serial number of the disk starting from the second, d _i = d _n , provided d _i > d _in , d _in is the inner diameter of the filter element, and the number packets in the filter element N _n according to the formula:

where H is the height of the filter element, k is the number of disks in one pyramid, including the central disk, n is the degree of compression of the filter material at the output of the filter element, which determines the nominal filter fineness d _0.95 .

 After crimping, each pair of disks of the same diameter, installed symmetrically with respect to the central disk, together with disks having a diameter larger than the diameter of this pair, form their filtration stage. At the same time, the degree of compression of the filter material in the steps increases in the direction from the outer radius to the inner one, and the pore size, accordingly, decreases. Due to multi-stage compression, the reduction in pore size occurs uniformly, which will avoid the localization of contaminants and evenly distribute them throughout the filter element, and therefore increase the dirt capacity and resource.

 Calculation example.

Required to produce a filter element providing a nominal filtration fineness d _0,95 = 20 ... 25 mm, and having the following dimensions: an outer diameter d _n = 100 mm, internal diameter d _in = 50 mm, a height H = 185 mm, thickness disks in a free state Δ ₀ = 10 mm As a deformable porous filter material, polyurethane foam of the PPU - EO - 130 brand is used.

Find the diameters of the disks. The diameter of the larger disk is equal to the outer diameter of the filter element:
d _n = d _i = 100 mm

d₃ = 86,6 мм,
d₄ = 71,4 мм,
d₅ = 43,2 мм < d_в = 50 мм - это означает, что число ступеней фильтрации k = 4.Using the formula (1), we determine the diameters of paired disks:

d ₃ = 86.6 mm
d ₄ = 71.4 mm
d ₅ = 43.2 mm <d _in = 50 mm - this means that the number of stages of filtration k = 4.

Find the number of filter packages. It is known that the relationship of the nominal filtration fineness d _0.95 with the compression ratio n for polyurethane foam grade PPU - EO - 130 is expressed by an empirical relationship [3]:
d _0.95 = 79.43 _n ^-1.466 • 10 ^-6 . (3)
In the table. 1 at the end of the description shows the values of the degree of compression and the fineness of filtration calculated from this dependence.

 According to the table 1 select the value of the degree of compression corresponding to a given filter fineness. We accept n = 2.3.

Полученное значение округляем до целого числа. Окончательно: N = 4.We determine by the formula (2) the number of filter packages:

The resulting value is rounded to an integer. Finally: N = 4.

 Ha FIG. 1 shows a general view of a volumetric filter element.

 In FIG. 2 shows a general view of a disc pack prior to compression.

 The filter element contains a cylindrical perforated frame 1, covers 2, elastic disks of various diameters, mounted on a perforated frame. The disks are pre-assembled into packages, each of which includes a central disk 3 with a diameter equal to the outer diameter of the filter element, and disks 4 of smaller diameters mounted on both sides in decreasing diameters and forming two symmetrical pyramids with a common base from the central disk. Discs are crimped onto a rigid cylindrical perforated frame with covers. After crimping, each pair of disks of the same diameter, installed symmetrically with respect to the central disk, together with disks having a diameter larger than the diameter of this pair, form their filtration stage. The degree of compression of the filter material in the steps increases in the direction from the outer diameter to the inner, and the pore size, respectively, decreases. The filter material at the outlet of the filter element has a compression ratio that ensures the required quality of liquid purification.

 The volumetric filter element operates as follows.

 Filtered liquid in the filtering process enters first in the outer stage, which has the largest pore size, where there is a delay of large particles of contaminants. Further, the filtered liquid passes sequentially through the remaining stages of filtration, each of which has a pore size smaller than the previous one, and ensures the retention of smaller fractions of contaminants. Thus, there is a selective delay of pollution inside the volume of the filter material. The last stage has a minimum pore size and retains the smallest particles of contaminants. Due to the selective retention of contaminants, they are evenly distributed within the volume of the filter element, thereby increasing the dirt capacity and resource.

Claims (1)

A volumetric filter element containing a rigid cylindrical perforated frame, elastic disks of various diameters and end caps for compressing disks located on it, characterized in that the disks of the filter element are assembled in bags, each of which includes a central disk with a diameter equal to the outer diameter of the filter element, and other disks installed on both sides of it in decreasing order of diameters, forming two symmetrical pyramids with a common base from the central disk, the disk diameters are determined yayutsya formula

where d _n is the outer diameter of the filter element;
Δ ₀ is the thickness of the disk in an uncompressed state;
i - serial number of the disk, starting from the second;
d _i = d _n , provided d _i > d _in ;
d _in - the inner diameter of the filter element,
and the number of packets in the filter element N _n according to the formula

where H is the height of the filter element;
K is the number of disks in one pyramid, including the central disk;
n is the degree of compression of the filter material at the output of the filter element, which determines the nominal filter fineness d _0.95 .

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