AU2001269038B2

AU2001269038B2 - Water treatment device

Info

Publication number: AU2001269038B2
Application number: AU2001269038A
Authority: AU
Inventors: Dietmar Ende; Hans Sautter; Michael Sautter
Original assignee: PERMA TRADE WASSERTECHNIK GmbH
Current assignee: PERMA-TRADE WASSERTECHNIK GmbH
Priority date: 2000-06-28
Filing date: 2001-05-25
Publication date: 2006-10-05
Anticipated expiration: 2021-05-25
Also published as: EP1301437B1; ES2230332T3; DK1301437T3; DE50104412D1; DE10030340C2; JP2004501749A; AU6903801A; US20040026238A1; ATE281413T1; WO2002000555A1; DE10030340A1; EP1301437A1; PT1301437E; CA2417096A1

Abstract

A water treatment device, having a housing with duct areas which are used to conduct the water to be treated. At least a first and a second electrode are accommodated in the housing. The first and second electrodes are alternately positive-poled and negative-poled. Electro-conductive material is introduced into the housing. In order to provide a water treatment device which can be operated on a permanent basis with a high degree of efficiency, the first and second electrodes are arranged in separate first and second electrode chambers which are insulated from each other by one or several insulating bodies, the electrode chambers are respectively filled with a bulk material of a uniform granulated material, and the insulating bodies are pervious to water to be treated but are impervious to the granulates forming the bulk material.

Description

WATER TREATMENT DEVICE The invention relates to a device for treating water, having a housing with conduit areas for conducting the water to be treated, wherein at least one first and one second electrode is arranged in the housing, wherein the first and second electrodes are alternatively positively and negatively polarized, and wherein an electrically conductive bulk material has been placed into the housing.

Such a device is known from WO 98/16477. This device is used for reducing, or preventing, the formation of scale in aqueous solutions. A housing is used there, into which a cartridge is inserted. The cartridge has two electrodes, each of which is arranged in an electrode chamber. A bipolar electrode is arranged in the area between the electrodes, which is embodied as a fixed bed. The fixed bed is constituited by a bulk material which on the one hand has electrically conducting carbon particles and on the other hand nonconducting insulating particles (for example pebbles, glass or plastic bodies). The nonconducting insulating particles insulate the carbon particles from each other, so that the formation of short circuits is prevented. A voltage is applied to the bipolar electrode via the electrodes. In the course of this the individual carbon particles are given a positive and a negative charge. The liquid to be treated is now conducted through the bipolar electrode.

The calcium contained in the liquid is precipitated in the form of calcite at the negative pole areas of the carbon particles. To prevent a calcite deposit in this pole area, the polarity of the electrodes is regularly reversed.

An even blending process in the bipolar electrode, and therefore the even distribution of the conducting and non- conducting particles, is of great importance for this known arrangement. However, mn actual use it has been shown that a segregation occurs in VO-628 Sthe bipolar electrode, for example in connection with its transportation or partially also in the course of its operational use. It then loses its effectiveness and the efficiency is drastically reduced.

It would be advantageous if the present invention would create a device of the type mentioned at the outset which can be operated over the long term at high efficiency.

00 The present invention provides in a first aspect such a device wherein the first and second electrodes are housed in first and second electrode chambers, which are separated C from each other and are electrically insulated from each other by means of one or more several insulating bodies, that each of the electrode chambers is filled by bulk material consisting of a uniform granulate, and that the insulating bodies are permeable to the water to be treated, but impermeable to the granulated bulk material. Polarized areas are created in the electrode chambers, in which a single fixed polarization exists for a defined length of time. Because of this division into unipolar areas, the homogeneously composed bulk material of the invention can be used, wherein a segregation as in the prior art is not a problem. It is therefore possible to assure dependable operation because of this combination of characteristics.

The present invention provides in a second aspect a device for treating water, having a housing with conduit areas for conducting the water to be treated, wherein at least one first and one second electrode is arranged in the housing, wherein the first and second electrodes are alternatively positively and negatively polarized, and wherein an electrically conductive bulk material has been placed into the house, characterised in that: the first and second electrodes are housed in first and second electrode chamber, which are separated from each other and are electrically insulated from each other by means of one or several insulating bodies; each of the electrode chambers is filled by bulk material consisting of a uniform granulate; and, the insulating bodies are permeable to the water to be treated, but impermeable to the granulated bulk material.

The bulk material can consist, for example, of granulated carbon, in particular activated charcoal, which is introduced into the electrode chamber in the form of a fixed bed.

Kirsite/keep/retype/P48129 retype claims 21/09/2005 SIn accordance with a preferred embodiment of the invention it is provided that the insulating bodies are embodied as bulkhead walls and have a screen-like passage area for the water to be treated, wherein the opening sizes of the openings constituting the passage areas are less than the granule diameters of the particles of the bulk material.

In order to be able to achieve the greatest possible flow introduction into the bulk 00 material it can be provided for the first and second electrodes to be embodied rod-like and to be surrounded over their entire length by the bulk material.

NO A possible embodiment of the invention can be distinguished in that a conduit area which is surrounded by an area which receives the electrode chambers is arranged in the housing, that the conduit area is in spatial connection with the electrode chambers via the openings, that the side of the electrode chambers which faces away from the conduit area in the radial direction is covered by means of a liquid-permeable shell, and that a conduit section adjoins the shell in the housing. In this case the conduit area can be selected to be such that initially the water to be treated is introduced through the central conduit section and thereafter flows through the electrode chambers and the peripheral conduit area.

However, a reverse conduct of the flow is also conceivable. A re-mixing of the electrolysis products resulting from the treatment is avoided with these types of flow conduction.

A device in accordance with an embodiment of the invention can be distinguished in that the electrode chambers are separated from each other by insulating bodies which substantially extend in the flow direction of the water to be treated. In this case the liquid to be treated flows parallel through the individual electrode chambers.

It is also possible to connect the electrode chambers in series in such a way that they are separated from each other by insulating bodies extending transversely in respect to the flow direction of the water to be treated, and that the electrode chambers are arranged on behind the other in the flow direction.

A combination of parallel and series connection is also conceivable.

For preventing an impermissible nitrite formation in the water, a further development of the invention provides that, viewed in the flow direction, an oxidation zone, through which the water treated in the associated electrode chamber, or in several electrode chambers is conducted, is arranged behind at least one of the electrode chambers. A fixed Kirsite/keep/retype/P48129 retype claims 21/09/2005 bed electrode which, for example, consists of carbon particles and has a positive polarity, ("4 Scan be connected downstream as the oxidation zone.

A calcite precipitation takes place only in the area of the negatively polarized Cc electrode chambers during the operation. For achieving the greatest possible efficiency, a O device in accordance with the invention can be designed in such a way that different volume flows of the water to be treated flow through the electrode chambers of different 00 polarisation. Alternatively, or additionally, it can be provided that the length of polarisation Sof the cathodic and the anodic phases of at least one of the electrodes is selected to be O different. In this case the water to be treated remains longer in the electrode chamber with negative polarisation.

SFor achieving the greatest possible even flow density in the electrode chambers, a C1 device can be designed in such a way that the electrodes are arranged at least partially concentrically in respect to the conduit area arranged in the housing, and that the electrodes, which are arranged on a graduated circle around the conduit area are distributed equidistantly in respect to each other in the ambient direction. For achieving an improved calcite crystal formation it can be additionally provided that the water to be treated flows through a magnetic treatment device prior to entering the housing.

The present invention provides in a third aspect a device for reducing or preventing scale formation in aqueous solutions, comprising a housing which has conduit regions for carrying the water to be treated, at least a first and at least a second electrode being accommodated in the housing, the first and second electrodes being alternately polarized positively and negatively, switching electronics being used which control the pole reversal operation, and a filling of electrically conductive material being introduced into the housing, characterised in that: the first and second electrodes are accommodated in first and second electrode chambers which are separated from each other and insulated electrically with respect to each other by means of one or more insulating elements in that the electrode chambers are in each case filled up by means of a filling of electrically conductive material which consists of uniform granules, and the insulating element is permeable to the water to be treated but impermeable to the granules of the filling.

The invention will be explained in greater detail in what follows by means of exemplary embodiments represented in the drawings. Shown are in: Fig. 1, a device for the treatment of water in a lateral view and in vertical section, Fig. 2, the device in Fig. 1 in horizontal section, and H:\Iisa~keep\Speci\retypc\P48129.doe 31/03/06 Fig. 3, a horizontal section through an embodiment variation of a device for the treatment of water which differs from Figs. I and 2.

00 H:\Jisafkep'Speci\ie\P48129.doc 31/03/06 .A device for the treatment of water which has a tube-thaped housing 25 is represented in Fig. 1. In its bottom area, the tube-shaped housing 2 5 is closed off by me ans of a support 10. The support 10 has a flange plate 11 which is in contact with the lower front face of the housing 25. The flange plate 11 constitutes a collar 12, on which the front face of the housing 25 is seated. A seal 13 is arranged in the area of the collar 12. This seal 13 seals the interior of the housing 25 against the surroundings. In the area adjoining the collar 12, the support 10 has a shoulder 14. This shoulder 14 is used for receiving a tube- shaped shell 23. The tube-shaped shell 23 is centered and aligned on a cylindrical protrusion 15 of the support 10. The protrusion 15 projects into the interior surrounded by the shell 23. A conduit section 20 is arranged in the center of the shell 23 and is embodied in the form of a tube, In its casing, this conduit section 20 has a plurality of openings. The conduit section is maintained on a blind bore 18 of the support 10. As shown in Fig. 2, four electrodes 22.1, 22.2 are arranged in the area between the conduit section 20 and the shell 23. In this case the electrodes 22.1, 22.2 are arranged concentrically in respect to the conduit section and each is offset by 90" from the other, The support 10 has electrode seats 17 in the form of bores for fixing the electrodes 22.1, 22.2 in place. Contacting of the electrodes 22.1, 22.2 takes place via contact springs 19.2, which have been inserted in a threaded receiver 16 which terminates in the electrode seat 17. A contacting element 19.1 has been screwed into the threaded receivet 16 and, on the one hand, presses the contact springs 19.2 against the electrodes 22.1, 22.2 and, on the other hand, can be connected to a power supply on the exterior of the housing 25. The remaining annular space between the conduit section 20 and the shell 23 is filled with a bulk material of electrically conductive material, for example activated charcoal. As had already been mentioned above, the conduit section 20 is provided with openings and is therefore embodied in a screen-like manner. The shell 23 is also VO-628 5

I

embodied in a screen-like manner. The openings of the screens are here of such a size that the particles of the bulk material cannot leave the space between the shell 23 and the conduit section 20, but that an electrical insulation between the adjoining areas is assured.

As Fig. 1 fuarther shows, a cap 30 has been pushed on the head of the shell 23.

The cap 30 has a shoulder 33 for this purpose, which receives the front face of the shell 23.

Furthermore, the cap 30 has electrode seats 34, which are embodied in the manner of a blind bore and in which the ends of the electrodes 22.1, 22.2 are received. A conduit section 36 passes through the center of the cap 30 and terminates in a widened seat 35. The end of the conduit section 20 is received in this seat 35. On its side facing away from the conduit section 20, the cap 30 has a shoulder 3 1, on which a cover 40 is sealingly held by means of a seal 32, The cover 40 encloses an outer chamber 41, which is spatially connected with a conduit area 24 formed between the housing 25 and the shell 23. The cover 40 moreover has an inner chamber 42, which is spatially connected with the conduit section 36 of the cap For assembling the device, first the support 101is inserted into the housing and is fastened in a suitable pressure-proof manner. Thereafter, the shell 23, the electrodes 22.1, 22.2 and the conduit section 20 are fastened on the support 10 from the direction of the top of the housing 25. Thereafter the bulk material can be inserted. Finally, the cap 30 is then inserted into the housing 25 on the cover side. Now the open top of the housing 25 can be closed with the cover As can be seen in Fig. 1, the cover 40 has a circumferential flange 43. This flange 43 rests on a radially outward oriented rim 3 7 of the housing 25, with a seal 44 placed between them, A screw ring 45 is used for connecting the cover 40 with the housing 25. An interior thread 47 of this screw ring 45 can be screwed on an exterior thread of the cover VO-628 In this case the screwing-on movement is limited by a detent 46 of the screw ring 45, which comes into contact with the underside of the rim 37.

As Fig. 2 shows, the space between the conduit section 20 and the shell 23 is divided into four electrode chambers 21.1,21.2. An electrode 22.1, 22.2 is arranged in each of these electrode chambers 2 1.1, 21.2. The division of the electrode chambers 21.1, 21.2 takes place by means of insulating bodies 50, which are embodied in the manner of a bulkhead wall. These insulating bodies 50 are permeable to liquid media, in particular aqueous solutions. But the insulating bodies 50 are impermeable to the granules of the bulk material. On their radial ends, the insulating bodies 50 are fixed in place in seats 51 of the shell 23, Or of the conduit section 20. On the one hand, these seats 51 prevent a displacement of the insulating bodies 50 and, on the other hand, they dependably prevent an electrically conducting connection between the individual electrode chambers 21.1, 21.2.

During operation, water to be treated is fed to the device represented in Figs.

1 and 2 via the inner chamber 42 of the cover 40. The water then flows through the conduit section 36 to the conduit section 20. Ini this case the water flows in the radial direction through the shell 23 of the conduit section 20. Thereafter, the water reaches the electrode chamber 21.1, 21.2. Each of the adjacently located electrode chambers 21,1, 21.2 is differently polarized. Accordingly, the electrodes 22.1 can be positively charged, the electrodes 22.2 negatively, A calcite precipitation out of the water to be treated ten takes place in the area of the negatively charged electrode chambers 21.2. In the process, the calcite is deposited on the individual carbon particles of the bulk material. A change in polarization takes place after a defined period of timae. The electrodes 22.1 are negatively polarized, the electrodes 22.2 positively. Because of the polarization reversal, the calcite deposits at the carbon particles are removed and are floated out like germns. The treated water VO-628 leaves the electrode chambers 21.1, 21.2 through the shell 23 in the radial direction. There, it flows to the conduit area 24 and can then be fed into a water main network via the outer chamber 41 of the cover 40. The above described flow direction can of course also be reversed, so that the water to be treated is first supplied to the outer chamber 4 1. In that case the water leaves the device through the inner chamber 42.

In the embodiment variation of the invention described in Figs. 1 and 2, the flow passes parallel through the electrode chambers 21.1, 21.2. It is also possible to provide a series connection of the electrode chambers 21.1, 21.2. Such an arrangement can be seen in Fig. 3. Here, a ring-shaped insulating body 50, which is arranged concentrically in relation to the conduit section 20 and the shell 23, is used in place of the radially arranged insulating bodies 50. Two electrode chambers 21.1, 21.2, which are embodied in a ring shape, are formed in this way. Respectively four electrodes 22.1, 22.2 are arranged in the individual electrode chambers 21.1, 21.2. The same as in the embodiment in Fig. 1, the individual electrodes are again arranged offset by 900 from each other. Based on this arrangement of the electrodes 22.1, 22.2, an optimal and even flow density is achieved within the individual electrode chamibers 2 1.1 and 2 1.2, In the embodiment variation in accordance with Fig. 3, the water to be treated flows -in through the conduit section 20 and here arrives radially through the shell 23 of the conduit section 20 into the first electrode chamber 21.2. Thereafter the water flows through the liquid-permeable insulating body 50 and reaches the second electrode chamber 2 1.1.

From here the water reaches the conduit area 24 through the shell 23 the same way as in the embodiment in accordance with Figs. 1 and 2.

Merely for the sake of completeness it should be mentioned here that basically the device in accordance with Fig. 3 is identical to the device in accordance wit Figs. 1 and VO-628 2. There is only a different arrangement of the electrodes 22.1, 22.2 and of the electrode chambers 21.1, 21.2.

Initially, the electrodes 22.2 can be negatively polarized in the electrode chamber 21.14 Accordingly a calcite precipitation takes place in the bulk material kept in the electrode chamber 2 1. 1. The water then flows through the second electrode chamnber 2 1.1 and flows off via the shell 23. A polarization change takes place after a defined perio d of time. The electrodes 22.2 then are positively polarized, the electrodes 22. 1 negatively. Now the calcite precipitation takes place in the bulk material of the electrode chamber 21.1.

During this state of the polarization, the calcite deposited on the carbon particles of the bulk material in the electrode chamber 31.2 is removed and flushed out wit the water to be treated. A change in polarization again takes place after a defined length of time.

It has been shown that in accordance with the invention a polarization change of more than 30 seconds provides good efficiency. If a shorter period of time is used, the effectiveness is reduced and with it the efficiency of the device.

For this reason it has also been shown to be advantageous to employ an electronic switching device for controlling the polarization-reversing process. In this case the individual flow- through times should be added when the water removal takes place in a clockecd manner. A polarization reversal ten takes place only after the preset total interval length.

A flow meter can be used for optimizing the operation. The latter determines the amount of water which flows through and is to be treated continuously or at time intervals. The treatment current strength is then regulated as a function of this determined value. A flow meter can also be used alternatively or in addition as an indicator of the time VO-628 for m aintenance. A signal i s emitted as s oon a s a d efined a mount o f w ater h as b een registered, which indicates the need for replacing the granular bulk material.

For being able to make determinations regarding the wear state it is possible to integrate a measuring apparatus in the device, which measures the conductivity of the granular bulk material.

An embodiment ofthe device in accordance with the invention can also be such that two or more groups of electrodes (22,1, 22.2) are formed. Initially, only one of the groups is operated until it is no longer sufficiently functional because of aging and/or output.

Then a switch is made to a second group, or the latter is hooked up.

VO-628

Claims

1. A device for reducing or preventing scale formation in aqueous solutions, Cc comprising a housing which has conduit regions for carrying the water to be treated, at least O a first and at least a second electrode being accommodated in the housing, the first and second electrodes being alternately polarized positively and negatively, switching 00 electronics being used which control the pole reversal operation, and a filling of electrically Sconductive material being introduced into the housing, characterised in that: the first and second electrodes are accommodated in first and second electrode chambers which are separated from each other and insulated electrically with respect to each Sother by means of one or more insulating elements, the electrode chambers are in each case filled up by means of a filling of electrically conductive material which consists of uniform granules, and the insulating element is permeable to the water to be treated but impermeable to the granules of the filling.

2. The device according to claim 1, characterised in that the filling consists of carbon granules as a fixed bed electrode.

3. The device according to claim 1 or 2, characterised in that the insulating elements are formed as partition walls and have a sieve-like passage region for the water to be treated, the opening widths of the openings forming the passage regions being smaller than the grain cross-sectional dimension of the particles of the filling.

4. The device according to one of claims 1 to 3, characterised in that the first and second electrodes are rod-like and are surrounded by the filling over their entire longitudinal extent. The device according to one of claims 1 to 4, characterised in that: in the housing there is accommodated a conduit region which is surrounded by a region which accommodates the electrode chambers, the conduit section is connected physically to the electrode chambers via the apertures, the side of the electrode chambers that faces away from the conduit section in the radial direction is covered by means of a liquid-permeable jacket, and in the housing, a further conduit region adjoins the jacket.

H:\JisafNkecp\Speci\typc\P48129.doc 31/03/06

6. The device according to one of claims 1 to 5, characterised in that the electrode Schambers are separated from one another by insulating elements running substantially in the flow direction of the water to be treated.

7. The device according to one of claims 1 to 6, characterised in that: 00 the electrode chambers are separated from one another by insulating elements running transversely with respect to the flow direction of the water to be treated, and, O the electrode chambers are arranged one after another in the flow direction.

8. The device according to one of claims 1 to 7, characterised in that the electrode chambers of different polarity are flowed through by different volume flows of the water to be treated.

9. The device according to one of claims 1 to 8, characterised in that the polarisation durations of the cathodic and the anodic phase of at least one of the electrodes are chosen to be different.

The device according to one of claims 1 to 9, characterised in that: the electrodes are arranged at least partly concentrically with respect to the conduit section arranged in the housing, and the electrodes, arranged on a part circle around the conduit section, are distributed equidistantly from one another in the circumferential direction.

11. The device substantially as herein described with reference to the drawings. DATED this 3 d day of April 2006 PERMA-TRADE WASSERTECHNIK GMBH By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia H:\Iisafkccp\Speci\itype\P48129.doc 31/03/06