CZ20013387A3 - Electric filter system - Google Patents

Abstract

The electrofilter system (1) comprises a filter unit (2), a prefilter unit (3) and at least one ventilator (5) for purifying an air stream. The filter unit has a filter cell (4) with a fine filter and the prefilter unit has a prefilter element (6) with a filter insert and a condensation chamber (7). The air stream is deviated once between the outlet from the condensation chamber and the inlet to the filter unit. Preferred Features: The air stream flows through the filter unit in the counter direction to the condensation chamber of the prefilter unit.

Description

Electrofilter system

Technical field

The invention relates to an electrofilter assembly with a filter unit, a prefilter unit and at least one blower for cleaning the air stream.

BACKGROUND OF THE INVENTION

Air purification systems, especially air filters, are well known in the art and are used in practice primarily to maintain air purity in process rooms and production halls. In the known electrostatic principle of working air filters, contaminated air is sucked in and first passes through, for example, a mechanical pre-filter in which coarse particles of dirt are removed. Thereafter, the particles present in the intake air are ionized in the electrostatic main filter by means of an ionization unit, so that the solid particles are deflected and adhered to the oppositely charged collecting plates. Liquid particles (eg oil or emulsion) travel from the collecting plates to the bottom of the cabinet and flow through the return line to the tank where they can be removed. Such systems pollute very quickly in a disadvantageous manner and then do not operate optimally. The known electrostatic air filters are therefore very maintenance-intensive and consequently cost-intensive.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide an electrofilter assembly which achieves optimum efficiency after

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9 9 9 9 9 9 ······ Longest possible lifetime, ensuring long life without the need for high maintenance costs.

This object is solved by an electrofilter assembly with the features of claim 1. Pursuant special embodiments are defined in the dependent claims.

According to the invention, the electrofilter assembly has a filter unit, a pre-filter unit and at least one blower for cleaning the air stream. The filter unit is provided with a fine filter chamber and the pre-filter unit has a mechanical pre-filter element having at least one filter module and a condensation space. According to the invention, the air flow between the outlet from the condensation space of the pre-filter unit and the inlet to the filter unit is reversed at least once. By reversing the direction of the air flow, it is achieved that the particles condensing in the filter unit are automatically guided into the condensation space of the pre-filter unit, flowing therein while simultaneously cleaning it. In addition, the pre-filter unit is cooled by means of particles already substantially cooled in the filter unit.

Preferably, the air flow direction in the filter unit is substantially opposite to the flow direction in the condensation space of the prefilter unit. By reversing the airflow by 180 °, maximum self-cleaning and cooling effect is achieved.

According to a further preferred embodiment, the pre-filter unit is vertically flowing through an air stream. According to yet another embodiment, the prefiltration unit is at least partially vertically flowing through the precipitated condensate. Vertical flow promotes the self-cleaning effect of the elements of the pre-filter unit, since condensed particles, for example, are eliminated

• Coolants and lubricants, when dripping, wash away a large part of the solid particles from the mechanical filters. In addition, the condensation space arranged in the prefilter unit is kept moist and cooled by the condensate discharged in the filter unit. This optimizes the efficiency of the pre-filter unit.

According to a further preferred embodiment, the filter unit and the pre-filter unit are located in respective housings. Preferably, the housings are arranged at least partially one above the other so that the condensate deposited in the filter unit is used to cool and clean at least a portion of the pre-filter unit without an additional return device. Furthermore, it is advantageous if the pre-filter unit and the filter unit are arranged exactly one above the other in the area of the condensation space of the pre-filter unit, so that the electrofilter assembly has a smaller construction height, with a minimum installation space requirement.

In a preferred embodiment of the electrofilter assembly according to the invention, the mechanical pre-filter element is variably equipped with filter modules which can be inserted into the condensation space, the individual filter modules being freely interchangeable. All modules can be replaced manually without the need for an additional tool, so that no special equipment is required. Expanded metal filters, vortex separators or agglomerators may be used as filter modules. By using vortex separators, the maintenance cycle of the pre-filter element and the fine filter can be extended. By means of a specially designed condensation chamber, particles in the gaseous and vapor phases can already condense in the pre-filter unit and be separated there. The condensation chamber is provided with specially formed impact plates, so that the air flow is repeatedly reversed here, which increases the condensation area or the airflow.

extends the excretion path, so that a considerable preliminary elimination is achieved.

In a special embodiment, the entire filter assembly can be kept compact by means of this condensation space in the prefilter unit.

Preferably, the overall electrofilter assembly is modularly constructed. Thus, the filter unit may be variably equipped, wherein the fine filter may consist of at least one electrostatic filter chamber or aerosol cassette filter. In addition, the electrofilter assembly can be connected to up to three suction points, the suction power at the individual suction points being independently adjustable. It is also possible to supplement the electrofilter assembly with a downstream filter chamber, wherein the downstream filter chamber may be provided with an activated carbon filter for odor absorption. Thanks to the modular design of the filter system, it is possible to adapt the filter system to a variety of requirements by combining special filter elements.

According to a further embodiment of the invention, when the pressure difference increases due to the increased settling of foreign particles, an electronic signal for the blower equipped with an integrated speed control is transmitted via the interface for controlling the blower speed. This ensures a constant suction power of the filter system.

Preferably, the blower is downstream of the filter unit and is also replaceable or replaceable. replaceable for different purposes. In addition, the integrated blower speed control allows the blower to be ideally set up for specific applications and thus further optimizes the efficiency of the filter system.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in one embodiment with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a prior art electrofilter assembly;

FIG. 2 is a cross-sectional view of an electrofilter assembly according to the invention;

FIG. 3 is a plan view of a filter module;

FIG. 4 is a sectional view of a condensation chamber.

DETAILED DESCRIPTION OF THE INVENTION

Fig. 1 is a perspective view of a prior art electrofilter assembly 2. The air stream L is passed unchanged first through the pre-filter unit 3, then through the ionization device 13 and between the downstream collector plates 14 of the filter unit 2, and finally reaches the downstream filter 15. Solid contaminants remain in the filter unit 2 adhered to the collector plates 14 and liquid particles, such as oil and emulsion, travel from the collecting plates 14 to the bottom of the housing (not shown) and flow back through a return line (not shown) to a collecting tank (not shown). The filtered air is returned to the environment after the subsequent filter unit 15.

FIG. 2 is a cross-sectional view of an electrofilter assembly 1 according to the invention. Of unfiltered air through the suction connection piece of the suction space 12 is introduced into the electrostatic system 1 and receives the first to the condensation chamber 7. Here, the air flow L repeatedly deflected by impact plates disposed in the condensing chamber 2 ^'C ° F in cooling air flow L. In the prefilter unit 3, which may contain up to five filter elements 6, three filter elements 6 are provided, equipped with mechanical filters. Between the outlet of the pre-filter unit 3 and the inlet of the filter unit 2, the air flow L is reversed. At the inlet of the filter unit 2, an inverted air flow L flows through the filter unit 2 in the opposite direction to the condensation space 7. The filter chamber 4 of the filter unit 2 is here designed as a single stage filter and is provided with one electrostatic filter chamber;

however, filter chambers may be provided. In the filter-cooled condensate flow perpendicularly to the space Ί_ of the pre-filter unit the space 7 cleans and cools. After in the case of the two-stage also two electrostatic chambers ejected and down to condensation

3, whereby the condensation flow through the condensation space 7 of the pre-filter unit 8 collects the condensate in the collecting tank and is discharged. The filter unit 2 and the pre-filter unit 3 are arranged one above the other in the respective condensation space 7 of the pre-filter unit 3 in the respective housings 10 and 11, thereby inter alia. also given the compact design of the electrofilter unit 6.

Giant. 3 shows a plan view of a filter module 8 in the form of a vortex separator which can be inserted into the pre-filter elements 6 of the pre-filter unit 3. FIG. 4 is a schematic illustration of the air flow through the condensation space 2. On the two opposing walls 17, 18 of the condensation chamber 2, there are arranged striking plates 9 which extend in a mirror-symmetrically offset manner at an angle to the walls 17 in the direction of the condensation chamber so that the air flow path L is not straight but on each striking plate changes the direction so that the condensation path is extended.

Claims (10)

An electrofilter assembly (1) with a filter unit (2), a prefilter unit (3) and at least one blower (5) for cleaning the air stream, characterized in that the filter unit (2) has a filter chamber (4) with a fine filter , the pre-filter unit (3) has a mechanical pre-filter element having at least one filter module (8) and a condensation chamber (7), and the air flow is between the outlet of the condensation chamber (7) of the pre-filter unit (3) and the inlet to the filter unit (2) turned at least once. An electrofilter assembly (1) according to claim 1, characterized in that the filter unit (2) flows through a stream of air in substantially the opposite direction to the condensation space (7) of the pre-filter unit (3). An electrofilter assembly (1) according to claim 1, characterized in that the pre-filter unit (3) flows substantially vertically through the air flow. An electrofilter assembly (1) according to any one of claims 1 to 3, characterized in that the prefilter unit (3) is at least partially vertically flowed through the precipitated condensate (16). An electrofilter assembly (1) according to any one of claims 1 to 4, characterized in that the air flow is reversed within the condensation space (7) by specially formed impact plates (9). An electrofilter assembly (1) according to any one of claims 1 to 5, characterized in that the filter unit (2) is located in the housing (10) and the pre-filter unit (3) is located in the housing (11). The electrofilter assembly (1) according to claim 6, characterized in that the housing (10) of the filter unit (2) and the housing (11) of the pre-filter unit (3) are arranged in such a way, in particular at least partially one above the other, the filter unit (2) is used to cool and clean at least a portion of the prefilter unit (3). Electrostatic filter assembly (1) according to one of Claims 1 to 7, characterized in that the pre-filter element (6) can be variably equipped with plug-in individual pre-filter modules (8) with filter modules (8) of the unit (3). interchangeable. An electrofilter assembly (1) according to any one of claims 1 to 8, characterized in that the variable filter modules (8) are expanded metal filters, vortex separators or agglomerators. An electrostatic filter assembly (1) according to any one of claims 1 to 9, characterized in that an electronic signal for the blower (5) provided with integrated control is transmitted to control the blower speed (5) when the pressure difference increases due to increased foreign particle deposition. speed.