DEVICE FOR SEPARATING LEGIONELLA

Abstract

A device for concentrating and separating Legionella and/or amoebas by acoustophoresis in tap water.

Claims

1. A device (1) for concentrating and separating Legionella and/or amoebas by acoustophoresis in tap water (4), comprising a flow chamber (2) having an inlet opening (5) through which the tap water flows in and an outlet opening (6) through which the tap water flows out, wherein the openings (5, 6) are opposite to one another, and an opening (7) for discharging concentrated Legionella and/or amoebas, wherein the flow chamber (2) has dimensions, preferably a length (L), a height (H), and a width (B), and at least two transducers (3) arranged outside the flow chamber (2), on two sides of the flow chamber (2) in each case, for applying acoustic energy to the flow chamber (2) to generate standing waves, wherein at least one of the dimensions of the flow chamber is designed in consideration of the acoustic contrast factor of the Legionella and/or amoebas so as to generate one or more frequencies and pressure amplitudes of the standing waves such that the Legionella and/or amoebas concentrate or accumulate in the pressure nodes of the standing waves.

2. A device (1) according to claim 1, wherein at least one of the dimensions of the flow chamber is designed in consideration of the acoustic contrast factor of the Legionella and/or amoebas so as to generate one or more frequencies and pressure amplitudes of the standing waves such that the pressure nodes, the standing waves generated by the transducers, are in a line with the opening for discharging Legionella and/or amoebas.

3. A device according to claim 1, wherein the flow chamber has a rectangular cross-sectional area.

4. A device according to claim 1, wherein the height H and the width B of the flow chamber are of different lengths.

5. A device according to claim 1, wherein the height (H) and the width (B) of the flow chamber (2) are designed in such a way that by means of the generated standing waves, an acoustic pressure or pressure difference of at least MPa, preferably 10 MPa and higher is generated in the flow chamber (2), preferably at a generated frequency of 15 kHz to 150 kHz.

6. A device (1) according to claim 1, wherein at least one of the dimensions of the flow chamber is designed in consideration of the acoustic contrast factor of the Legionella and/or amoebas so as to generate one or more frequencies and pressure amplitudes of the standing waves which have a minimum acoustic pressure or pressure difference in the center of the cross section (A) of the flow chamber (2) of 0 MPa.

7. A device (1) according to claim 1, wherein the standing waves in the flow chamber (2) are in the range of 15 kHz to 150 kHz, preferably in the environment of a resonance frequency of the flow chamber, which is preferably constructed from a low-damping material, and thus requires the least possible energy consumption.

8. A device (1) according to claim 1, wherein the maximum acoustic pressure or pressure difference of the flow chamber (2) is inversely proportional to the square root of the acoustic contrast factor of the Legionella and/or amoebas.

9. A device (1) according to claim 1, wherein the length (L) of the flow chamber is 15 mm to 150 cm.

10. A device (1) according to claim 1, wherein the height (H) of the flow chamber is at least 16 mm and the width (B) is at least 16 mm.

11. A device (1) according to claim 1, wherein the flow chamber (2) has a variable wall thickness (w) having depressions and material thickenings of at least 1 mm and at most 10 mm.

12. A device (1) according to claim 1, wherein the flow chamber (2) is produced from a material compatible with tap water, which moreover reflects acoustic waves and absorbs little, such as preferably copper alloys, especially preferably gunmetal, brass, or rustproof steels.

13. A device (1) according to claim 1, wherein the transducers are aligned perpendicular to the longitudinal axis of the flow chamber and are arranged on the same plane and also on different planes along the longitudinal axis of the flow chamber (2).

14. A device (1) according to claim 1, wherein the transducers (3) are formed from a piezoelectric element or a layered piezoelectric element.

15. A device (1) according to claim 1, wherein the transducers are connected to a mass or an oscillating piston (10), wherein the oscillating piston (10) is connected via a spring element (11) to the flow chamber (2).

Description

DRAWINGS

[0032] An exemplary embodiment of the invention will be described on the basis of the figures, wherein the invention is not only restricted to the exemplary embodiment. In the figures:

[0033] FIG. 1 shows a schematic illustration of a device according to the invention,

[0034] FIG. 2 shows the cross-section of a flow chamber, and

[0035] FIG. 3 shows a spring-mass system for connecting the transducer to the flow chamber.

[0036] The drawing shown in FIG. 1 shows a schematic representation of a device 1 according to the invention. The device for concentrating and separating Legionella and/or amoebas by acoustophoresis is arranged in a water line 4. The device 1 includes a flow chamber 2, which is connected at each of the two end faces via inlet and outlet openings 5, 6 to the pipeline 4. The tap water flows through the flow chamber 2 accordingly. The transducers 3 for generating the acoustic energy are arranged on at least two sides of the flow chamber 2. Wherein one transducer 3 is arranged on a side of the width B and one transducer 3 is arranged on a side of the height H, respectively. Pressure field superpositions are achieved by the sound waves generated via the transducers 3 due to the rectangular cross section, as is apparent in FIG. 2, and because the height H and the width B have different lengths, the Legionella and/or amoebas are also carried or guided from the corners into the middle to the pressure nodes. The Legionella and/or amoebas collected in the pressure nodes are then guided via an opening 7 for discharging the Legionella and/or amoebas, which is also preferably on a line with the pressure nodes. A pipeline 8 for discharging the Legionella and/or amoebas preferably adjoins the opening 7. It has proven to be advantageous if the height H and the width B are designed in such a way that the acoustic pressure or pressure difference in the flow chamber 2 is at least 5 Mpa, preferably 10 Mpa and higher. Wherein the transducers 3.1 and 3.2 are preferably operated in the environment of a resonance frequency of the flow chamber, which is preferably constructed from a low-damping material, and thus the least possible energy consumption is applied. The sound waves preferably propagate at a frequency of 15 kHz to 150 kHz in the tap water. The pressure nodes, which extend at least over a part of the length L of the flow chamber 2, thus preferably form in the center of the cross section A. It is advantageous if at least an acoustic pressure or pressure difference of 0 MPa is present in the center, due to which the Legionella and/or amoebas accumulate there and are guided into the opening 7.

[0037] FIG. 3 depicts the spring-mass system 9, which represents the connection between the flow chamber 2 and the transducer 3. The oscillating piston preferably has a width of at least 40% of the width of the flow chamber, wherein the illustrated embodiment covers the complete width. The piston 10 therefore contacts the tap water located in the flow chamber. The oscillating piston 10 is mounted in a spring element 11, which is connected to the flow chamber 2.