The present invention relates to an apparatus for the gasification of liquids, especially for the aeration of water.
Such apparatus are used, for example, in clarification plants. A plurality of aeration elements are disposed on a distribution conduit, whereby the distribution conduit on the one hand serves for the supply of air or gas to the aeration elements, and on the other hand also serves for the securement of the aeration elements. A plurality of distribution conduits can in turn be combined to form a system.
An elongated aeration element is disclosed in DE 33 19 161A1. In addition, DE 36 00 234 discloses an apparatus for the aeration of water, according to which individual aeration elements are connected with the distribution conduit via fittings that during assembly are pressed into a bore in the distribution conduit accompanied by elastic deformation, thereby forming a positive connection. However, the aeration elements are plate-shaped elements. Such a connection is not suitable for elongated aeration elements, which can have an aeration length of up to and greater than one meter. When the apparatus moves or if there are flows in the liquid that is to be aerated, the long aeration elements act like lever arms, so that the forces that occur at the connection locations are much greater than is the case with plate-shaped aeration elements.
It is therefore an object of the present invention, for an apparatus of the aforementioned general type, to provide a connection between aeration element and distribution conduit that is suitable for long aeration elements, and in addition is elastic in order to be able to compensate for movements of the apparatus or flows in the liquid, and that nonetheless is easy to assemble and that requires only a few straightforward components.
This object, and other objects and advantages of the present invention, will appear more clearly from the following specification in conjunction with the accompanying schematic drawings, in which:
The object of the present invention is realized with an apparatus for the gasification or aeration of liquids, especially for the aeration of water, and includes elongated aeration elements that are connected with a distribution conduit that serves for the supply of gas or air, whereby each aeration element has an essentially rigid support tube, optionally, with a rounded groove in its surface, lengthwise, with a membrane of rubber or a rubber-like polymeric material that is disposed on the support tube, and whereby compressed air or gas can be introduced between the support tube with a membrane of rubber or a rubber-like polymeric material that is disposed on the support tube, and whereby compressed air or gas can be introduced between the support tube and the membrane and can escape into the liquid that is to be gasified via slits in the membrane; disposed between the distribution conduit and aeration element is an fitting having optionally a rubber or rubber-like flange on a cylindrical element, and a semi-rigid plastic saddle, whereby the fitting is disposed in a bore that passes through the wall of the distribution conduit, with a fitting having a flat saddle section, one side of which rests against the outer wall of the conduit and the other side of which rests against the end of the aeration element, and whereby a hollow bolt is securely connected fitting and into the interior of the distribution conduit, with the fitting being supported against the distribution conduit and being provided with apertures in its wall on that section thereof that is disposed in the interior of the distribution conduit.
As a consequence of the inventive fitting, an elastic mounting is achieved. The bolt serves not only for the mechanical connection, but also, due to is hollow configuration, for the transport of the air or gas from the distribution conduit to the aeration element. The bolt can be connected with the aeration element by being screwed thereto, whereby pursuant to one advantageous embodiment of the invention, due to an interlocking between aeration undesired loosening or detachment of the screwed connection.
Pursuant to a particularly advantageous embodiment of the invention, aeration elements are respectively disposed in pairs on opposite locations on the distribution conduit, whereby in a given cross-sectional plane, the distribution conduit is provided at two oppositely disposed locations with bores through which a single bolt passes that connects the two aeration elements with one another. In this way, the support of the bolt relative to the wall of the distribution conduit is effected by the respectively other aeration element. The aeration elements thus reciprocally support one another, and the apparatus can make do with a minimum number of parts.
Further specific features of the invention will be described in detail subsequently.
Referring now to the drawings in detail, the improved apparatus is provided with a distribution conduit 1 on which are disposed two aeration elements 2 and 3. The right aeration element 3 is shown in section, and the left aeration element 2 is illustrated as being dismounted from the distribution conduit 1. The aeration elements 2,3 extend perpendicular to the distribution conduit 1. The distribution conduit 1 can be equipped with a plurality of such pairs of aeration elements 2,3. The construction and manner of operation of the aeration elements 2,3 will be briefly explained subsequently.
Each of the aeration elements is provided with a support tube 5 of an essentially rigid material, for example a tough polymeric material, on which is disposed a hose-like membrane 4 that elastically surrounds the support tube 5 and in the following is also designated as a sleeve. The sleeve 4 is held by a clamp 6. In the drawing, only a short section of the elongated aeration elements 2 and 3 are shown. A clamp 6 can also be provided at the non-illustrated end of the aeration element for securing the sleeve 4 on the support tube 5.
The end of the aeration element 3 is closed off by a wall 7. The wall 7 can be connected with, or merged into, the support tube 5 in any desired manner. Formed between the wall 7 and a partition or intermediate wall 8 is a chamber 9 that serves for the supply of air to the aeration element 2, 3. In the vicinity of the chamber 9, the wall of the support tube is provided with apertures 10.
The other non-illustrated end of the support tube 5 is open, so that the water or other liquid that surround the apparatus has access to the interior of the support tube 5 up to the partition 8. As a consequence of this manner of construction, during operation only a small portion of the support tube 5 is filled with air, and the buoyancy of the apparatus is therefore low, which is of particular advantage for very long aeration elements 2,3.
The sleeve 4 is made of an elastic material, especially rubber or a rubber-like polymeric material. Furthermore, the sleeve 4 is provided with a plurality of fine slits, which as can be seen with respect to the aeration element 2 are designated by the reference numeral 11. However, these slits are provided only in that portion of the aeration element 2,3 that, as viewed from the securement location, is disposed behind or downstream of the partition 8, whereas the sleeve 4 has no slits in the region of the chamber 9.
During operation, compressed air flows from the chamber 9, via the apertures 10, between the support tube 5 and the sleeve 4, and escapes via the slits in the sleeve as fine bubbles into the surround liquid.
The important thing now is the connection of an aeration element 2 or 3 with the distribution conduit 1. A pin or bolt 13 serves for this purpose, and together with a fitting 12 extends through bores 15 in the distribution conduit 1.
As shown in
As depicted in
In the cross-sectional plane illustrated in
The bolt 13 is embodied as a hollow tube. The central portion of the bolt is provided with apertures 23 via which the bore 22 in the interior of the bolt 13 communicates with the distribution conduit 1. By means of the apertures 23, air is guided out of the distribution conduit 1 and via the bore 22 into the chambers 9 of the two aeration elements 2, 3, from where the air eventually passes via the membranes or sleeves 4 into the liquid that is to be gasified. The bolt 13 thus serves not only for the fastening of the aeration elements 2,3, but also for the supply of air or gas.
The apparatus is equipped with devices that prevent the components of the apparatus from becoming unintentionally detached. For example, each of the end walls 7 of the aeration elements 2 and 3 is provided in the region of its periphery with recessed areas 24 that, as can be seen in
The cylindrical portion 14 of the fitting 12 is provided with ribs 29 that on the side of the free end of the cylindrical portion 14 rise in a flat manner, while on the side of the flat portion 16 of the fitting 12 drop off more steeply. As a consequence of this barbed configuration of the portion 14, the fitting 12 is easy to insert into the bore 15, yet an undesired detachment is prevented.
It is furthermore important that with the apparatus of the present invention, all connection locations are sealed, and in particular not only to prevent unnecessary pressure losses, but also to prevent penetration of dirty water. In order to increase the sealing effect, the outer surfaces 17 and 18 of the flat portion 16 of the fitting 12, as well as in bore 19, are provided with circumferential sealing rings or ridges 30,31 and 32 that seal these components relative to the aeration elements 2,3 the distribution conduit 1, and the bolt 13.
The preceding elements of the improved invention are disclosed in U.S. Pat. No. 6,769,673 to Jäger which is incorporated herein by reference. The following elements are improvements on the '673 device and are commonly owned.
A new embodiment of the fitting 12 not only has the inclined surfaces 27 of the wedge-shaped projections 26 which glide over the ribs 25 and finally engage in the recessed areas 24 of aeration elements 2 or 3, but also wedge-shaped projections 26′ on the opposing relative surface of the cylindrical opening of flat portion 16 such that the perpendicular surfaces 28′ of the projections 26′ then prevent an unscrewing between flat portion 16 and essentially cylindrical portion 14, i.e., fitting 12 components, flat portion 16 and essentially cylindrical portion 14 are interlocked. As with the earlier embodiments, the saddle or flat portion 16 then rests against the outer surface of the distribution conduit 1, whereby it is provided with a concave abutment surface 17 that corresponds to the curvature of the outer surface of the distribution conduit. The opposite outer surface 18 of the fitting 12 rests against the wall 7 at the end of the aeration element 2 or 3.
This is an improvement over prior art devices in that the saddle and the cylindrical portion lock themselves into place by expansion against the distribution conduit 1 in the manner of a wall anchor. This process is further aided by utilizing a further alternate embodiment which utilizes a plastic as the flat portion 16 material. This serves to provide a slightly deformable fitting yet provides sufficient rigidity to stabilize the fitting to avoid stress failure and allows for expansion against the distribution conduit 1. Again, improvement in the device can be achieved by allowing the flange 25 of cylindrical portion 14 to be comprised of rubber or a rubber-like plastic or mixture thereof. It improves further over the prior art by allowing additional “sealing” areas to both increase aeration and prevent device failure due to material fatigue. Seals are formed between the saddle and the distribution conduit, including the outside of the pipe and in the opening of the pipe through which the fitting (including the saddle) passes; between the saddle and the aeration element; between the saddle and the cylindrical portion of the fitting.
Another improvement on the earlier device can occur with the use an aeration element with a central rib, as shown in
A further improvement in the present invention is use of a “groove tube” embodiment of a tube diffuser aeration element. In present devices, the diffuser area of the sleeve forms an external crease when depressurized. This potentially weakens the sleeve material and can shorten the life expectancy of the sleeve. Surprisingly, the invention utilizing the groove tube can lower the pressure drop of air/gas traveling between the membrane and support tube by approximately 25% which reduces the energy consumption of the system, and can prevent the sleeve forming a crease in the de-pressurized state thereby extending the life expectancy of the unit. As shown in
The invention modified with the groove tube, is shown in
This is further assisted by orientation of the embodiment with two grooves 42, 42′ on the aeration element 2, disposed opposite one another lengthwise along tube 5. Utilizing the opposing grooves and specific slit 11 formations in sleeve 4 allows for the maximum utilization of the sleeve without deterioration. Such slit formation, as shown in
The specification incorporates by reference the disclosure of German priority document DE 101 50 180.3 filed Oct. 12, 2001, and U.S. Pat. No. 6,769,673.
The present invention is, of course, in no way restricted to the specific disclosure of the specification and drawings, but also encompasses any modifications within the scope of the appended claims.