GB1573585A - Method of and a device for collecting impurities in room air - Google Patents

Description

(54) A METHOD OF AND A DEVICE FOR COLLECTING IMPURITIES IN ROOM AIR (71) We, ILMASTI OY of Pälkäneentie 20, 00510 Helsinki 51, Finland, a Finnish company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a method of collecting impurities contained in a restricted air space, especially in room air, wherein the impurities are caused to adhere to particles in the air and an electric field oppositely charged in relation to the particles in the air is generated in the room, said electric field catching the impurities adhered to the particles in the air.

The invention is related to the problem caused in apartments, public premises, hospitals etc. by impurities, such as dust, smoke, bacteria, viruses and other contaminants contained in air when efforts are made to improve the comfort of staying in such rooms and to prevent the spreading of contagious diseases and harmful particles.

The removal and collection of impurities contained in air has hitherto been carried out, for example, in hospitals by means of air filters connected to the air conditioning systems for the rooms. but the cleaning capacity of such devices is unable of meeting an exacting use because smaller impurity particles pass the filters. In industrial use, various electric separators and filters are known for cleaning smoke gases and similar, but these apparatuses have, like all cleaning devices, the disadvantage of containing mechanically moving parts subject to wear and requiring service, in addition to which they are noisy in use due to their motors, impellers etc.

Moreover, these devices consume a considerable quantity of electric current and, in use, produce undesirable air currents in the rooms.

It is an object of the present invention to provide a method of collecting impurities contained in room air, which method does not require mechanic ventilation, i.e. positive blowing of air through a device collecting the impurities, but which makes it possible to collect the impurities by means of utilizing the normal currents of air in a room space.

According to the invention there is provided a method of collecting impurities contained in air in a room, wherein the impurities are caused to adhere to charged particles and an electric field, oppositely charged in relation to the particles, is generated in an electrically conductive liquid in a vessel in the room, said electrically charged liquid capturing the impurities adhering to the particles in the air.

When applying the method to hospitals, a bactericidal and virucidal liquid is preferably used as liquid in the vessel, whereby the impurities are not only made harmless but are also collected in the liquid. Also very small particles can be efficiently caught by the liquid.

Preferably, special ionizators are used in the room space to generate negatively charged electric particles to which the impurities easily adhere, whereby the liquid in the vessel is positively charged. The separation capacity of the method can in this way be considerably improved for special purposes. Ordinary room air generally contains electric particles without artificial ionization in such a quantity that a capacity of 10 to 20 percent can be obtained by this method as compared to the biggest collecting capacity obtained when using ionization.

The method makes it possible to reduce the amount of ventilation and, accordingly, in many cases to save energy.

According to a second aspect of the invention there is provided a device for collecting impurities contained in air in a room, comprising an ionizer for generating charged particles in the room air, a vessel, an electrically conductive liquid contained in said vessel and exposed to the room air, and means for applying to the vessel an electrostatic potential of a polarity to attract the charged particles generated by the ionizer to the liquid in the vessel.

The invention will now be described in more detail with reference to the accompanying drawings, in which: Figure 1 is a schematic vertical section of a hospital ward provided with a preferred embodiment of a collecting device according to the present invention; Figure la is a particle enlargement of Fig- ure 1; Figure 2 is an enlarged view of the collecting device; Figure 3 is a perspective view of a second embodiment of the collecting device; Figure 4 is a perspective view of a third embodiment of the collecting device; and Figure 5 is a side view of a fourth embodiment of the collecting device.

In the drawing, Figure 1, shows a hospital ward 1 provided with a window 2 and a heating radiator 3. An ionizator 4 known per se is fastened to the ceiling of the room and a collecting device 5 is arranged below the heating radiator.

Room air normally contains electric particles formed by ions, which particles adhere to dust, bacteria and other impurity particles in the air, whereby the impurity particles are charged. The amount of ions contained in room air can be increased in a way known per se by means of the ionizator 4 which substantially promotes the charging of the impurity particles. The negative ions generated by the ionizator are marked with the reference numeral 6 and the bacterium particles in the air by the reference numeral 7. The negatively charged bacterium particles are marked with the reference numeral 8. During heating, air circulates automatically in the room along flow paths indicated by the arrows A.

A charge of an opposite polarity, in this case an electric field B having a positive polarity, is generated in the collecting device 5. When air currents pass the electric field in the collecting device, the positively charged field attracts the negatively charged bacterium particles so that the bacteria remain in the collecting device. Air free from bacteria flows upward and the ion content thereof again increases sharply when the air flows through the negative field C created by the ionizator. Because the process is continuous, the room will be supplied with cleaned air containing negative ions while the actual need for ventilation decreases. Negative ionization has, moreover, been found to be helpful in various diseases etc.

Without the collecting device, the impurity particles would accumulate on fixed surfaces, such as walls, in the room said surfaces being by nature somewhat positively charged.

Fig. 2 is an enlarged view of the collecting device 5. It consists of an elongated vessel 9 filled with an electrically conductive liquid 10, in this case a bactericidal liquid. The device includes a converter 11 known per se which is coupled by a wire 12 to an electric supply, for example, to a conventional 220V AC net 13. The converter is provided with a high voltage transformer, by means of which the voltage is raised to a desired level, for example, to 5000 V, and a diode, by means of which a negative voltage of the same size is generated in the wire 14, the free end of which is immersed in the liquid 10.Converters of this type are used, for example, in the ionizators "Ilma 4" manufactured by Ilmasti Oy. A positively charged electric field B is rhus generated in the liquid so that the liquid attracts the negatively charged bacterium particles, as described above. When getting in contact with the disinfectang liquid the bacteria are killed. Dust and other con tåminating particles are naturally also collected in the liquid.

The amount of current required by the device according to the invention is very small, 0.5 kW, wherefore no special protective measures are needed. The consumption of electricity is, accordingly, very small.

In the embodiment shown in Fig. 3, the vessel 9, the liquid 10 and the means 11-14 generating the electric field are the same as above. A roller 15 is arranged above the vessel, the longitudinal axis of said roller being parallel to the liquid surface. The lower portion of the roller is submerged in the liquid. The roller is rotated by an electric motor 16 via suitable reducing gears. In this embodiment, the collecting surface can be enlarged and bacteria and impurities adhering to the roller are washed off into the liquid. The roller is made of an electrically conductive material and obtains its positive charge from the liquid.

In the embodiment shown in Fig. 4, the collecting surface is further enlarged by means of an endless metal strip or net 17 surrounding three parallel rollers 18.

In the embodiment shown in Fig. 5, a plurality of discs 19 are rotatably mounted above the vessel and rotated by an electric motor (not shown).

The drawing and the accompanying specification are only intended to illustrate the idea of the invention. In its details, the method according to the invention and the collecting device for carrying out said method may vary considerably within the scope of the claims. Experiments made have proved that, when using the arrangement described and an ionizator and a collecting device having a voltage of 5000 V and an electric current of abt. 7 ,uA, the amount of impurity particles in a single patient room in a hospital can be continuously kept close to the zero value, whereby the main part of the impurities is collected by the collecting vessel. If no disinfecting action is required, for example, water can be used in the vessel.

When necessary, the electric field generated by the ionizator can be positively charged and the electric field generated by the collecting vessel negatively charged. Although the above description relates to the application of the method to an air space defined by a closed room, it is obvious that the invention can also be applied to partly closed spaces, such as balconies and similar semi-open spaces in hospitals.

In some cases, when the liquid vessel has to be placed too close to e.g., wall surfaces, it may be advisable to provide the vessel with special side plates to limit the area of action of the electric field, as shown in Fig. la. Various electrically conductive elements, such as balls, can also be placed in the vessel, said elements affecting the profile of the electric field.

WHAT WE CLAIM IS: 1. A method of collecting impurities contained in air in a room, wherein the impurities are caused to adhere to charged particles, and an electric field, oppositely charged in relation to the particles, is generated in an electrically conductive liquid in a vessel in the room, said electrically charged liquid capturing the impurities adhering to the particles in the air.

2. A method as claimed in Claim 1, in which the liquid is a bactericidal liquid.

3. A method as claimed in Claim 1 or 2, wherein the impurities are caused to adhere to electrically charged particles generated in the room air by means of ionization.

4. A device for collecting impurities contained in air in a room, comprising an ionizer for generating charged particles in the room air, a vessel, an electrically conductive liquid contained in said vessel and exposed to the room air, and means for applying to the vessel an electrostatic potential of a polarity to attract the charged particles generated by the ionizer to the liquid in the vessel.

5. A device as claimed in Claim 4, in which the liquid contained in the vessel is bactericidal.

6. A device as claimed in claim 4 or 5, comprising a movable collecting member which along a portion of its path of motion is submerged in the liquid in the vessel and which is made of an electrically conductive material so that the collecting member has the same charge as the liquid in the vessel.

7. A device as claimed in claim 6, in which the collecting member comprises a rotary roller, the axis of rotation of which is parallel to the liquid surface in the vessel, the lower part of said roller being partly immersed in the liquid.

8. A device as claimed in claim 7, in which the collecting member comprises an endless net, strip or the like rotatably supported on rollers, the axes of rotation of which are parallel to the liquid surface in the vessel, the lower part of the lowermost roller being at least partly immersed in the liquid.

9. A device as claimed in claim 6, in which the collecting member comprises one or several discs.

10. A device as claimed in any one of the claims 4 to 9, wherein the ionizer serves to generate negatively charged electric particles in the room air, the liquid in the vessel being connectable to receive a positive charge.

11. A device for carrying out the method of claim 1, substantially as herein described with reference to and as illustrated in Fig. 2, 3, 4, or 5 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (11)

**WARNING** start of CLMS field may overlap end of DESC **. a hospital can be continuously kept close to the zero value, whereby the main part of the impurities is collected by the collecting vessel. If no disinfecting action is required, for example, water can be used in the vessel. When necessary, the electric field generated by the ionizator can be positively charged and the electric field generated by the collecting vessel negatively charged. Although the above description relates to the application of the method to an air space defined by a closed room, it is obvious that the invention can also be applied to partly closed spaces, such as balconies and similar semi-open spaces in hospitals. In some cases, when the liquid vessel has to be placed too close to e.g., wall surfaces, it may be advisable to provide the vessel with special side plates to limit the area of action of the electric field, as shown in Fig. la. Various electrically conductive elements, such as balls, can also be placed in the vessel, said elements affecting the profile of the electric field. WHAT WE CLAIM IS:

1. A method of collecting impurities contained in air in a room, wherein the impurities are caused to adhere to charged particles, and an electric field, oppositely charged in relation to the particles, is generated in an electrically conductive liquid in a vessel in the room, said electrically charged liquid capturing the impurities adhering to the particles in the air.

2. A method as claimed in Claim 1, in which the liquid is a bactericidal liquid.

3. A method as claimed in Claim 1 or 2, wherein the impurities are caused to adhere to electrically charged particles generated in the room air by means of ionization.

4. A device for collecting impurities contained in air in a room, comprising an ionizer for generating charged particles in the room air, a vessel, an electrically conductive liquid contained in said vessel and exposed to the room air, and means for applying to the vessel an electrostatic potential of a polarity to attract the charged particles generated by the ionizer to the liquid in the vessel.

5. A device as claimed in Claim 4, in which the liquid contained in the vessel is bactericidal.

6. A device as claimed in claim 4 or 5, comprising a movable collecting member which along a portion of its path of motion is submerged in the liquid in the vessel and which is made of an electrically conductive material so that the collecting member has the same charge as the liquid in the vessel.

7. A device as claimed in claim 6, in which the collecting member comprises a rotary roller, the axis of rotation of which is parallel to the liquid surface in the vessel, the lower part of said roller being partly immersed in the liquid.

8. A device as claimed in claim 7, in which the collecting member comprises an endless net, strip or the like rotatably supported on rollers, the axes of rotation of which are parallel to the liquid surface in the vessel, the lower part of the lowermost roller being at least partly immersed in the liquid.

9. A device as claimed in claim 6, in which the collecting member comprises one or several discs.

10. A device as claimed in any one of the claims 4 to 9, wherein the ionizer serves to generate negatively charged electric particles in the room air, the liquid in the vessel being connectable to receive a positive charge.

11. A device for carrying out the method of claim 1, substantially as herein described with reference to and as illustrated in Fig. 2, 3, 4, or 5 of the accompanying drawings.