FI116201B - Hose for aeration of fluids - Google Patents

Abstract

Hose for aeration of a flow medium, such as in biological sewage processing is free of perforations at the free ends of the hose (1) in the zone (T) around its periphery where it is connected to a tail end (2). Other sections have wall zones free of perforations, which lie diametrically opposite when the hose (1) is pressed together into a kinked point.

Description

116201

Fluid aeration hose Slang för luftning av flytande medier 5

The present invention relates to a hose for aeration of fluid media, which includes peripheral holes for introducing a small bubble gas into a liquid medium.

10

The supply of oxygen to the liquid is of particular importance for a number of technical uses, and particularly for maintaining biodegradation processes during biological waste water treatment. In accordance with the principle of operation of the devices required for this purpose, a hollow body is provided at the bottom of the liquid container, through which the pressurized gaseous medium introduced into the hollow body through the holes 15 is removed. Due to the large amounts of oxygen required, this causes considerable energy costs.

Thus, a prerequisite for energy saving gas treatment is the introduction of a small bubble gas * · * * 20 into the liquid phase. For this purpose, aeration elements in the form of tubes, plates, plates and hoses * ·: · 'are known. This prior art is described in DE 32 24 177 A1, DE 36 32 772 Cl, DE 93 18 675 UI and DE 86 14 739; * V UI. These publications are mentioned by way of example only, since a large • · · * · · "!. number of patented and unprotected methods and equipment.

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25: With known aeration devices, there is usually the problem that air bubbling stifles in the aerated liquid through the aerator * »#. ···. In this case, smaller ,, · bubbles occur in increasing numbers, associated with larger bubbles.

• * · 30 This phenomenon is known in professional circles as "merger". Such; merger processes significantly reduce the gas supply to the liquid.

To avoid this disadvantage, DE 36 32 772 discloses an annular, mainly circular ring element for gas supply. This element includes a central opening through which a significant loss occurs in the gasification surface in use. This causes a greater pressure drop in the carburettor itself, whereby larger bubbles are formed on the carburettor surface. To avoid this disadvantage, the gas flow to the carburettor must be reduced, increasing the number of aerators installed in the carburettor and increasing the investment cost for the user.

DE 14 739 UI discloses a 10 tubular device for aeration of media. This tubular aeration element includes openings in a circularly distributed manner that are closed in an unloaded state and open in the event of increased pressure in the hollow space to the degassing line.

The disadvantage of such a hollow aerator body piercing is that the hose becomes compressed due to the pressure reduction caused by the external fluid pressure. The perforations in the peripheral areas of the compressed hose do not close at all, or do not close completely when bending stresses occur during compression, allowing the external fluid to penetrate the · · · *. inside the hose.

! ;; V 20. Also in the area of hose connections, the perforation of the hose aerator has certain disadvantages.

• · ·; * V At the junction of the gas detector hose detector, the hose becomes a gas- • * · », ·; ·. more or less deflected upwards due to the feed.

: 25 In the area of this deviation, the holes will be stretched, resulting in: '*'; larger bubbles than in undirected perforation areas. However, these larger bubbles: 'are not suitable for the desired aeration operations. In addition, in the case of gas disconnection, back flushing, which expands the aeration tube under pressure, the hose halves may not overlap directly at the transition portion of the connection area, whereby * * '; 30 perforations in this area remain more or less open. This requires an internal support core that seals the aeration hose against external overpressure.

3, 116201

It is an object of the present invention to avoid the disadvantages of the present state of the art and to provide a hose for aeration of media which prevents fluid from entering the hose at the connecting and lateral folds. In accordance with the invention, it is proposed that the free ends of the hose be kept free of holes through the hose nozzle throughout its circumference, and that the sub-areas of the hose circumference also include longitudinally extending hole-free wall portions located diametrically forming folding points.

The fact that the hose according to the invention is kept at its free ends free from holes means that the hose attachment area remains above the hose nozzle and is furthermore without holes for a predetermined length. In this way, the expansion of the gaps in this region due to gas pressure and the resulting rise of the hose is prevented. Thus, the formation of large bubbles 15 in the connection area, which are caused by the expansion of the expanded slits, is prevented.

Depending on this, pressure loss and fluid penetration in connection with external overpressure will also be prevented.

As a result of the longitudinal, non-perforated hose wall areas of the invention, the hose does not contain any larger through holes in the flank area during the preparation of the perforation, which is usually done by knitting. .:: Through the larger bubbles could cause the above-mentioned problems to come out.

Furthermore, these perforated wall areas prevent the pores from being trapped in the flanks during closed gas release and subsequent shrinkage of the hose due to the exerting fluid pressure, allowing the liquid to penetrate the hose.

and, furthermore, when the hose is placed in the aeration device, on the one hand, they increase the resistance of the hose against twisting.

116201 4

In a particularly preferred embodiment, in the longitudinal, non-perforated wall areas, opposite grooves are formed on the outer surface of the hose.

These grooves form nominal folds that ensure a certain amount of collapse in the event of external overpressure.

10 The perforated peripheral area at the free ends of the hose is dimensioned according to the general formula E = T + D + fE. In this formula, E denotes the length of the perforated peripheral area, T denotes the length of the aeration hose in the hose fitting, and D the diameter of the hose, where fE> 1. The benefits of this procedure have already been described in detail.

The longitudinal, perforated wall areas are obtained in accordance with the invention by the general formula K = 2 x s x f2, where K denotes the width of the longitudinal, perforated wall area, s the wall thickness of the hose and fk> 1. Advantages obtained in this manner have also been previously described.

• * V ..: 20 The gasification hoses according to the invention are freely tightened between the gas supply • • '* · hose fittings. Thus, the sealing elements required in connection with conventional gasification systems between the bearing structure and the gasification portion are omitted. With this ··· ': the presence of inactive areas during use is virtually * ·' prevented.

25 t; · ;;; The gasification hoses according to the invention achieve a flow pattern of the gases in the liquid, characterized by small bubbles. These small air bubbles are already truncated by flow from the gasification hose surface and are led to pass into the liquid medium before reaching the critical bubble size. In this way, the tubing diameter avoids the fusion of approximately small air bubbles. Because bubbles as large on the underside of the hose as on its upper side, flow is also achieved at the bottom of the tank, which reliably prevents the sludge from settling

Exemplary embodiments of the gasification hose according to the invention are schematically illustrated in the accompanying drawings, in which:

Figure 1 shows a hose in the clamping area of the hose fitting;

Fig. 2 shows the hose according to Fig. 1 without internal pressure; 10

Fig. 3 is a sectional view taken along line E-E of Fig. 2;

Fig. 4 is a sectional view taken along line D-D of Fig. 1.

The figure shows a hose 1 in the clamping area of the hose bushing 2 The hose bushing 2 belongs to a pre-connected gasification device not shown in the drawings. The hose 1 itself is shown in longitudinal section and this figure does not show the hose clamping at the opposite free ends. However, this clamping constitutes a mirror image of the clamping area shown and can thus be omitted from the drawings.

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The length E denotes the length of the unpunched peripheral region of the hose 1, by means of which: the partial length T in the hose fitting 2 is formed. The letter D indicates the diameter of the hose 5. '·. The gas comes in the direction of the arrow of the stub tube 2 and the non-perforated perimeter region! · 'Through E C. The length of the area which is not under tension in the neck 2, the tube 25 of perforated areas of the inner wall provided with a cross-section. From it gas flows out of the holes'; ;; through the central lumen of the hose in the direction of the arrow around the liquid into the atmosphere.

Figure 2 shows the hose of Figure 1 viewed from the inside without pressure.

1 ··· 'Hose 1 is collapsed in the perforation area due to external fluid overpressure.

/ 30 The transition area between the collapsed hose and the end T of the hose attached to the sleeve 2 is conical to the edge of the sleeve. Because there are no holes in the surface of the hose in this area, no harmful whirlpools are formed.

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Figure 3 is a sectional view taken along line E-E of the hose 1 of Figure 2 showing that the hose is compressed in its perforated areas 11.12 due to external fluid pressure. The peripheral regions 13,14, in their perforated form, are not compressed, but form longitudinal through openings to the edges of the tube.

Axially extending strips 15 or grooves 16 are formed at the highest points of these wall areas.

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Figure 4 finally shows an internal pressure pressurized hose 1 in cross-sectional view along line D-D of Figure 1. Again, both variants of the wall areas are shown, strips 15 on the one hand and grooves 16 on the other hand. The central separation line of the hose diameter shown in the figure indicates that there are moldings 15 or grooves 16 on both sides.

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Claims (5)

116201 A hose for aeration of liquid media provided with a peripheral hole for introducing a small bubble gas into the liquid medium, characterized in that the hose (1) is held at its free ends in the connection region (T) with the hose nozzle (2) The regions include longitudinal, non-perforated wall regions (13,14) which form diametrically opposed regions in the event of collapse of the hose (1). Hose according to Claim 1, characterized in that the length of the unpunched peripheral area (13,14) at the free ends of the tubing is dimensioned according to the general formula E = T + DxtE, where E is the length of the unperforated peripheral area, 2), D the diameter of the hose (1), and fE> 1. Hose according to Claim 1, characterized in that the longitudinal unpunched wall areas (13,14) are obtained from the formula K = 2xsxfK, where K represents the longitudinal unreflected wall area, s the wall thickness of the hose, and fK> 1.: i .: 20 Hose according to Claims 1 and 3, characterized in that longitudinal strips (15) are formed in the area of the longitudinal unpunched wall areas (13, 14) on the surface of the hose. A hose according to claims 1 and 3, characterized in that a longitudinal unpunched wall area (13,14) is formed on the surface of the hose ;;; diametrically opposed grooves (16). i: 116201