ES2301415B1 - SEPARATOR DEVICE OF ELECTROSTATIC PARTICLES. - Google Patents

Abstract

Particle separating device electrostatic

Electrostatic separator device particles for cleaning a gaseous medium, especially air, contaminated with particles, which includes: a flow channel (2); two collector electrodes in the form of plates (4), which are facing each other, with an intermediate space (B) between them, which form the two facing walls of the flow channel (2); a ionization device with a discharge electrode (6) arranged over a certain distance (d) to a respective collector electrode (4), to generate free electrical charges in the middle and to electrically charge the particles in the middle by these free charges, where the discharge electrode (6) in the channel flow (2) defines an ionization zone (Z_), and the distance predefined (d) for free electrical charges represents a distance dependent resistance (R1); and a resistance (R2; R2_ {T1}, R2_ {T2}) independent of distance, arranged at least within the ionization zone (Z_ {)}, between the discharge electrode (6) and a respective collector electrode (4), for free electric charges.

Description

Particle separating device electrostatic

Technical field

The present invention relates to a electrostatic particle separator device.

State of the art

Particle separating devices for cleaned of a gaseous medium, especially air, contaminated with particles, normally include a flow channel as well as two collector electrodes in the form of plates, which are located facing each other over an intermediate space, those that form two facing walls of the flow channel. Such devices Particle separators also have a device for ionization with a predetermined distance to a corresponding  collector electrode assigned to a discharge electrode, which serves to generate free electrical charges in the middle and to charge electrically the particles in the middle by these charges free. The charged particles are precipitated to the electrodes collectors

The ionization device or its electrode Discharge generates a strong electric field. It's about, in the case of the gaseous medium to be cleaned, of air or of others oxygen-containing gases, thus oxygen tends, in the / (that) medium, to bind to / in ozone (O 3) of three atoms. Ozone is a gas, which in concentrations greater than 200 µg / m3 is harmful For health or toxic. Ozone is in the process of separation or cleaning of the gaseous medium, usually it is by therefore a secondary product, which to avoid risks of health, must be again removed from the environment. For this they are required in electrostatic separating devices of conventional particles, relatively ozone filters Dispendious

Representation of the invention

The invention is therefore based on the task, or the technical problem, of conceiving a device of improved particle separation, which has a particle separation device while a reduced ozone production

The task is solved through a particle separation device in accordance with the invention with the features of claim 1.

This device according to the invention for the cleaned of a gaseous medium, especially air, contaminated with particles, includes:

a flow channel;

two plate-shaped collector electrodes facing each other with an intermediate space, which form two opposite walls of the flow channel;

an ionization device with an electrode of download arranged at a predetermined distance to a respective collector electrode, to generate free electrical charges (ions or fine air / gas molecules) in the middle and to charge electrically the particles in the middle by these charges free,

where

the discharge electrode in the flow channel define an ionization zone, and

the default distance for loads Free electric represents a resistance dependent on the distance; Y

and at least one resistance independent of the distance within the ionization zone, between the electrode of discharge and a respective collector electrode for electric charges free.

The discharge electrode is connectable properly to a high voltage source, so that she form a loading zone around it or an area of Effect-Crown with a strong electric field. In this Charge zone ions or free electrical charges are generated, the which are able to charge the particles that are in the middle or in the air. The ionized gaseous medium or the ionized air becomes electrically conductive. Between discharge electrode and a neighboring collector electrode circulates through such a reason a slight current I. From a point of view Microscopic follows this effect approximately to Ohm's Law:

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o bien R1 = U/I

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o bien I = U/R1.U = R1 * I

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or R1 = U / I

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or I = U / R1.

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OR

here is the level of the high voltage applied to the discharge electrode;

I

is the measure of the electric current, which circulates between the discharge electrode and one of the collector electrodes in the charging zone or in the ionization zone through the ionized gaseous medium; Y

R1

is the distance dependent resistance for free charges; this resistance R1 results through the predetermined distance between the discharge electrode and one of the neighboring collector electrodes.

The energy of electric charges in the area The load depends on the level of the high voltage U and the part ratios / proportions geometric-constructive device particle separation The higher the voltage U, the more  great is the effect of ionization and with it, after all Particle separation power of the device. An increment of the voltage U well will improve in conventional devices the particle separation power, however at the same time it will also raise the production of ozone (O 3).

The geometric relationships in a device electrostatic particle separation are normally preset This means that the distance between the electrodes of discharge and a neighboring collector electrode is fixed. Also high voltage U is normally kept constant. The inventors have at purpose discovered that under these circumstances, the production of ozone and with it the concentration of ozone generated in the channel of flow is proportional to the electric current I, which circulates at through the ionized gaseous medium between the discharge electrode and the adjacent collector electrode. Ozone production can by it be expressed approximately with the formula

O_ {3} -Production = k \ text {*} I

Here is k a constant, and for I it is worth I = U / R1.

Through electrical resistance independent of distance, ordered according to the invention at least in the ionization zone, between the discharge electrode and one of the neighboring collector electrodes, is thus offered to free electrical charges an additional resistance, so that high total electrical resistance is formed in this way R_ {GES}.

The above dependent electrical resistance of the distance R1 and the electrical resistance independent of the distance R2 is formed in the configuration according to the invention a kind of series resistor circuit, where for the total electrical resistance R_ {GES} the following can be applied formula:

R_ {GES} = R1 + R2

For the electric current I is worth it

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o bien I = U/R_{GES}I = U / (R1 + R2)

 \ hskip1cm 

or I = U / R_ {GES}

It is evident therefore that with a high constant voltage U, the electric current I circulating through of the gaseous medium from the discharge electrode to an electrode Neighbor collector, is considerably smaller. By consequently ozone production is also reduced approximately proportionally in the same dimension.

Important is naturally that resistance Electric independent of distance R2 is not chosen so large, such that the electrical resistance dependent on the distance R1, which is in relation to the electrical resistance total R_ {GES}, inhibits the electrical circulation through the medium gas between the discharge electrode and a collecting electrode neighbour.

The inventors have also discovered that despite the elevation of the total electrical resistance R_ {GES}, what (in relation to a high voltage U equal and the same geometric parameters) leads advantageously to a reduction considerable ozone compared to devices conventional, does not influence the ionization power of the electrode of discharge and with it the electric charge of the particles contained in the gaseous medium. The precipitation power of Device particles remain therefore existing. In other words: the electrostatic filtering power of device according to the invention is not negatively influenced by reducing the intensity / amperage of the current I. In this way it is possible to achieve an electrostatic device of particle separation, which with the increased power of particle separation simultaneously has a considerable reduction of ozone production. Depending on the type of construction are not necessary therefore no filters of special ozone or with a low filtering power of ozone.

Other preferred embodiment features and advantageous of the device according to the invention, they are subject to the dependent claims, which find their support in the description below.

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Examples of preferred embodiments of the invention with additional details relating to the configuration and other advantages are described and explained in more detail to then, and referring to the illustrations attached.

Brief description of the illustrations

It shows:

Fig. 1 a schematic view in section longitudinally through an electrostatic device of particle separation according to the invention in accordance with a first embodiment;

Fig. 2 a schematic view in section longitudinally through an electrostatic device of particle separation according to the invention in accordance with a second embodiment;

Fig. 3 a schematic view in section longitudinally through an electrostatic device of particle separation according to the invention in accordance with a third embodiment;

Fig. 4 a schematic view in section longitudinally through an electrostatic device of particle separation according to the invention in accordance with a fourth embodiment;

Representation of the examples of embodiments preferred

In the description that follows and in the figures appear the same parts and components indicated with the same reference symbols, as long as they are not necessary Other differentiations

A view is shown in Fig. 1 schematic in longitudinal section through a device electrostatic separation / precipitation of particles according to the invention in accordance with a first embodiment; This device for cleaning a gaseous medium (here: air) contaminated with particles, includes a flow channel 2 as well as two collector electrodes 4 in the form of plates, which are located facing each other separated by an intermediate space B. These collector electrodes 4 form two facing walls of the channel flow 2. The device is further provided with a device ionization that has a discharge electrode 6 in the form of thin wire As can be recognized in Fig. 1, the electrode of discharge 6 is within the flow channel 2 and ordered in a distance to the entrance of the flow channel 2, between collector electrodes 4. The distance d of the discharge electrode 6 towards a corresponding collector electrode 4 is here constructively predefined. The discharge electrode 6 serves to generate free electrical charges in the air, that means for generate ions or ionized air molecules and to charge electrically the particles in the air by these shit free.

For this purpose, the electrode is connected discharge 6 to a high voltage source 8, which applies a high voltage U to the discharge electrode 6. The discharge electrode 6 forms around itself a strong electric field E and an area Effect-Crown K, and thus define in the channel of flow 2 an ionization zone Z_ which in relation to the flow direction S has in flow channel 2 a long determined. The high voltage level U defines the zone size Effect-Crown K around the electrode of download 6 and with it especially the width of the area ionization Z_ {i} across (see reference symbol B corresponding) of the flow channel 2. The high voltage U is adjusted so that the Crown-Effect Zone K or the ionization zone Z_ extends over the whole of the cross-sectional area of the flow channel 2. All particles that penetrate the flow channel 2 with the air flow S must for this reason necessarily pass through the area of Effect-Crown K or the ionization zone Z_ {i} and are thus electrically charged.

The distance d determined between the electrode of discharge 6 and a neighbor collector electrode 4 represents for the free electrical charges generated in the ionization zone Z_ {i} a resistance dependent on distance R1.

The collector electrodes 4 are connected also to the high voltage source 8 and are loaded into it example with a polarity opposite the discharge electrode 6.

The device according to the invention also has a resistance R2 independent of distance, which resistance R2 is disposed within the ionization zone Z_, between the discharge electrode 6 and a respective collector electrode 4. This one resistance R2 independent of distance is formed in it exemplary embodiment, as an electrical insulation element in shape of a thin plate 10. This insulation element electric 10 can be designated in current language also as "dielectric". The electrical insulation element 10 has a permittivity (i.e. a transmissibility for the field electric E formed around the discharge electrode 6), which is smaller or much smaller than that of the air in the channel flow 2. In the present case, the electrical insulation element 10 is built with a plastic plate. In principle they can also be used however other materials or products with a permittivity or resistance to disruptive discharges appropriate. Important is, that the average resistance to discharges disruptive electrical insulating element 10 be higher or noticeably higher than average discharge resistance air disruptive (approx. 3.3 KV / mm).

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Appropriate materials for the element of Electrical insulation 10 are especially plastic (eg PVC with approx. 50 KV / mm, polystyrene with approx. 100 KV / mm, ABS with approx. 120 KV / mm, etc.), fiber composite materials, rubber, paper (10 KV / mm), glass, ceramic, porcelain (20 KV / mm), and similar.

The insulation element 10 in the present example is a piece and a sheet. In principle it can be built however of several pieces and / or several sheets. In in case that insulation element 10 is constructed of several sheets, the sheets can then be on top of each other or, instead, arranged with a distance between them. This distance It can be maintained by means of separators. The element of insulation 10 may also be produced from one or several materials. In the present example it is produced from a only plastic material, ie ABS. The element of insulation 10 of the embodiment according to Fig. 1 has a surface closed. However, embodiments in the which are provided cavities, convexities or as well as perforations or pores in the insulation element 10. These perforations can influence the resistance respectively total or local resistance in a surface element of the insulation element 10.

As can also be seen in Fig. 1, the insulation element 10 is placed in a laminar form in the inner side of the flow channel 2 in the collecting electrode 4. This one placement took place in the present case through a component of appropriate adhesion. The insulation element 10 may in principle be fixed however also mechanically.

In the present embodiment, it has the insulating element 10 a constant plate thickness, in the width direction and elevation direction of the flow channel 2. This thickness may vary considerably depending on the case of application. Thus the thickness of the plate can be located in the micrometric range (folio-shaped insulation element) or also in the millimeter range. In the present case the thickness of the plate is approx. 0.5 mm The previous songs and rear of the insulation element 10 are oblique, so that the  insulation element 10 is integrated in the flow channel in advantageous way to flow.

The insulation element 10 extends over the entire height of the respective collector electrodes 4 in the flow channel 2. The invention of course is not restricted without However, this type of realization. The height of the element of insulation 10 may be in certain cases also less and with in the direction of elevation expose the corresponding collector electrode 4.

As further schematized in Fig. 1, the insulation element 10, in relation to the flow direction S, extends in the flow channel 2 over the entire area of ionization Z_. According to the embodiment, the length L of the Insulation element 10 may however be smaller or larger. The length L of the insulation element 10 in Fig. 1 is composed in principle of two partial lengths, that is, the one referring to the flow direction S and discharge electrode 6 in favor of the current, partial length L_ {B}, and partial length L_ {C} against the current, that is L = L_ {B} + L_ {C}. The parts of length L_ {B} and L_ {C} can be the same here or also different.

Each respective insulation element 10 covers completely the corresponding collector electrode 4, this is by over the entire ionization zone Z_ {i} or in principle completely.

It is also possible according to the invention, that the plate-shaped electrical insulation element 10 seen in the direction of the flow S exceed the ionization zone Z_ {i}. This is indicated in Fig. 1 by dashed lines and by the additional partial part of length L_ {D}. The element of insulation 10 in the opposite direction to the flow direction S, it can also exceed the ionization zone Z_ {i}. This is indicated in Fig. 1 by means of dashed lines and the part additional partial length L_ {A}. The insulation element 10 may accordingly, referred to the direction of flow S exceed Forward or backward the ionization zone Z_ {i}. The parts of length L_ {A} and L_ {D} can be the same here or also different. The total length L of the insulation element 10 is in this case then L = L_ {A} + L_ {B} + L_ {C} + L_ {D}.

The respective insulation elements 10 They are grounded. This prevents over time, the corresponding insulation element 10 is loaded, which would restrict the electrostatic filtering effect of particles from device according to the invention.

It should be noted that a partial part of the respective collector electrode 4 must remain uncovered, the which referred to the direction of the flow S is found before the ionization zone Z_ {i}. (that is to the side of the entrance of the flow channel 2), preferably in front of the element of Insulation 10. This has been proven advantageous for the functionality of the device according to the invention, especially for particle separation / precipitation power, reducing simultaneously ozone.

The collector electrodes 4 in the present case they are removable or removable. This It is possible to remove the collector electrodes 4 for cleaning or for maintenance reasons. Simultaneously with cleaning or maintenance of the collector electrodes 4 can take place then also a cleaning of the insulation elements 10.

Fig. 2 shows a schematic view in section longitudinally through an electrostatic device of particle separation according to the invention in accordance with a second embodiment This variant resembles in principle that according to Fig. 1. Different / different from how it is in the case of Fig. 1, the electrical insulation element in the form of plate 10 however is deposited in a laminar form in a concavity or convexity 4a of the collecting electrode 4. This is a provision that especially favors the flow. The element of insulation 10 is otherwise made from a material plastic, which was injected into a molding procedure by injection directly in convexity 4a. This is in terms manufacturing technicians especially easy to make and low cost.

A schematic view in longitudinal section through a device according to the invention in accordance with a third embodiment is shown in Fig. 3. In this variant, the plate-shaped electrical insulation element 10 has a plate thickness, which is different depending on the site. In this sense it has a partial element T1 of the insulation element 10, which in relation to the discharge electrode 6 has a smaller distance d1, a greater plate thickness. A partial element T2 instead, which in relation to the discharge electrode 6 has a greater distance d2, has in contrast only a smaller plate thickness. In this way it is possible in principle to make available in essence a constant total resistance R_ {GES-T} of the partial elements in the insulation element 10. This results as a result of the partial element T1 due to its short distance d1 towards the discharge electrode 6 it also has only a small partial resistance R1_ {T1} depending on the distance. For a desired constant total resistance R_ {GES-T} of the partial elements, the partial resistance R2_ {T1} independent of the distance must then be large. As for the partial element T2 instead, the distance d2 is large, and with it also the partial resistance R1_ {T2} dependent on the distance. Therefore, the partial resistance R2_ {T2} independent of distance, in comparison with the partial element T2, may be smaller. For R_ {GES-T} voucher
so:

R_ {GES-T} = constant = R1_ {T1} + R2_ {T1} = + R1_ {T2} + R2_ {T2}

The principle described above in relation to the longitudinal direction the insulation element 10, also It is applicable to the lifting direction, where it should be provided attention to the arrangement of the discharge electrodes 6, the geometry of the electric field and the local intensity of the field.

According to the thickness layout / distribution of the insulation element 10, depending on the need, can naturally in another embodiment also be achieved provisions different from partial resistances.

A view is shown in Fig. 4 schematic in longitudinal section through a device electrostatic particle separation according to the invention according to the invention in accordance with a fourth embodiment. In this variant plate-shaped electrical insulation element thin 10 in the flow channel 2 is freely placed between the discharge electrode 6 and an assigned collector electrode 4, and in essence parallel to it. In this case it is also possible to conform the insulation element 10 as a flow grid or as a part of it.

The invention is not restricted to the foregoing. Examples of realization Within the scope of protection of the claims included, the device according to the invention and the process according to the invention can also adopt other design forms or embodiments other than those They have been described above specifically. The device can here present especially characteristics that represent a combination of the characteristics of the embodiments described.

The discharge electrode should not be necessarily a wire. The discharge electrode may be shaped in the form of several wires or also be provided with elements in the form of an elongated element, with needles, spines, teeth, or other sharp or pointed edges or elements similar. It is also possible that the discharge electrode, referred to the direction of flow, be arranged downstream of the collector electrodes and in front of them. In case that edge free of the collector electrodes form an input edge of the flow channel, so can also a part of the element of insulation seen from the inside of the flow channel being formed outward around this free edge or cover it At least in part. Such an embodiment is less effective than in the embodiment examples explained above, she is without However, it can also be carried out in the context of the invention.

In addition the insulation element can also possess a three-dimensional structure. Here you can at least one variant of subareas realization of this three-dimensional structure also directly or indirectly adjacent to the collector electrode or be subject to it, and on the contrary other zones no.

A collector plate with the element of electrical insulation in the form of a plate, can be prefabricated as a separate building unit. In the same way it is possible precast as a module the flow channel or those parts of the flow channel which have independent resistance or Well the electrical insulation element. Several such type of flow channels may be arranged in a device according to the parallel and / or serial invention.

The reference symbols that appear in the claims, description and illustrations serve only for a better understanding of the invention, and should not Limit the scope of protection.

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Reference List

2

Flow channel

4

Collector electrodes

4th

Convexity in 4

6

Discharge electrode

8

High voltage source

10

Insulation element in the form of plates

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B

Distance between collector electrodes 4

d

Distance

d1

Minor distance

d2

Greater distance

AND

electric field

K

Crown effect

L

Total length of 10

THE}

L partial length

L_ {B}

L partial length

L_ {C}

L partial length

L_ {D}

L partial length

       \ vskip1.000000 \ baselineskip
    

R1

Distance dependent resistance

R1_ {T1}

Partial resistance dependent on the distance of T1

R1_ {T2}

Partial resistance dependent on the distance of T2

R2

Resistance independent of distance

R2_ {T1}

Partial resistance independent of distance from T1

R2_ {T2}

Partial resistance independent of distance from T2

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S

Air flow

T1

Partial Element of 10

T2

Partial Element of 10

OR

High voltage

Z_ {i}

Ionization zone

Claims (17)

1. Electrostatic device for separation of particles from a gaseous medium, especially air, contaminated with particles, which includes:

-

a flow channel (2)

-

two collector electrodes in the form of plates (4), which are facing each other, with an intermediate space (B) between them, which  they form two opposite walls of the flow channel (2);

-

a ionization device with a discharge electrode (6), arranged in a certain distance (d; d1, d2) to a respective collector electrode (4), to generate free electrical charges in the medium and to electrically charge the particles in the middle through these free charges,

where

the electrode of discharge (6) in the flow channel (2) defines an ionization zone (Z_ {i}), and

distance predefined (d; d1, d2) for free electric charges represents a resistance (R1; R1_T1, R1_2) dependent on distance; Y

-

a resistance (R2; R2_ {T1}, R2_ {T2}) independent of the distance, arranged at least within the ionization zone (Z_ {)}, between the discharge electrode (6) and a respective collector electrode (4), for free electrical charges.

2. Device according to claim 1, characterized because distance independent resistance (R2) is formed by means of an electrical insulation element plate-shaped (10). 3. Device according to one or more of the claims set forth above, characterized in that the electrical insulated element shaped of plate (10) is placed in a laminar form on the electrode collector (4). 4. Device according to one or more of the claims set forth above, characterized in that the electrical insulated element shaped of plate (10) is deposited in a laminar form in a convexity (4a) of the collector electrode (4). 5. Device according to one or more of the claims set forth above, characterized in that the electrical insulated element shaped of plate (10) in the flow channel (2), is freely positioned between the discharge electrode (6) and a collector electrode (4) assigned, and in principle parallel to it. 6. Device according to one or more of the claims set forth above, characterized in that the electrical insulated element shaped of plate (10) extends over the entire height of the electrode plate-shaped manifold (4) in the flow channel (2). 7. Device according to one or more of the claims set forth above, characterized in that the electrical insulated element shaped of plate (10) has a constant plate thickness. 8. Device according to one or more of the claims set forth above, characterized in that the electrical insulated element shaped of plate (10) has a plate thickness, which is different according to the site. 9. Device according to one or more of the claims set forth above, characterized in that a partial element (T1) of the element of electrical insulation in the form of a plate (10), which, in relation to with the discharge electrode (6) it has a smaller distance (d1), has a larger plate thickness, while a partial element (T2), which in relation to the electrode of discharge (6) has a larger distance (d2), as opposed to this, a smaller thickness. 10. Device according to one or more of the claims set forth above, characterized in that the electrical insulated element shaped plate (10) in relation to the flow direction (S) in the channel flow (2), extends over the entire ionization zone (Z_ {i}) or in essence over the entire ionization zone (Z_ {i}). 11. Device according to one or more of the claims set forth above, characterized in that the electrical insulated element shaped of plate (10) seen in the direction of flow (S) exceeds (L_ {D}) the ionization zone (Z_). 12. Device according to one or more of the claims set forth above, characterized in that the electrical insulated element shaped of plate (10) in the opposite direction of flow (S) exceeds (L_ {A}) the ionization zone (Z_ {)}. 13. Device according to one or more of the claims set forth above, characterized in that the electrical insulated element shaped Plate (10) is grounded. 14. Device according to one or more of the claims set forth above, characterized in that a partial zone of the respective electrode manifold (4), which in relation to the direction of flow (S) is is before the ionization zone (Z_ {)}, is not covered by the plate-shaped electrical insulation element (10) 15. Device according to one or more of the claims set forth above, characterized in that the discharge electrode (6) within the channel of flow (2), is arranged between the collector electrodes (4). 16. Device according to one or more of the claims set forth above, characterized in that the discharge electrode in relation to the flow direction is arranged flow down the electrodes collectors and in front of them. 17. Device according to one or more of the claims set forth above, characterized in that the ionization zone (Z_) of the electrode discharge (6) extends over the entire surface of the section transverse flow channel (2).