DE3421484A1 - Silencer, in particular for flue gas desulphurisation plants - Google Patents

Abstract

A silencer is proposed which is applicable in particular even to flue gas desulphurisation plants, through which therefore a comparatively acidic medium flows, the pH of which is below 2.5. In this silencer, in a channel through which flows the effluent medium, there are accommodated packings acting by the absorption or resonance principle which are composed of synthetic fibres resistant to acidic media, the fibre diameter of which is between about 2 mu m and about 20 mu m, the fibres being compressed so that the length-specific resistance to flow is at least three kNs/m<4>. The packings are preferably composed of polypropylene fibres and are present in the form of bound felts or plates, the crude density of which is between 30 and 200 kg/m<3>.

Description

Silencers, in particular for flue gas desulphurisation systems.

The invention relates to silencers, in particular for flue gas desulfurization systems, in which in one vc ~ outflowing medium flowed through channel after the Absorption or resonance principle, effective fillings are accommodated.

The job of silencers is to keep in from the outflow Mefium channels flowed through the gaseous medium as unhindered as possible, d. H. without great loss of pressure to let it happen, but a spread of the at To largely prevent the sound from flowing through. With this prevention of sound propagation, there is sound energy converted into thermal energy by filling or cladding the duct walls or the scenes arranged in the duct with an absorption material. In particular In the case of flue gas desulfurization systems, silencers are necessary, those in the wet area because of the low / - ^ pE-T-Jertes of the flowing medium no mineral or May have glass wool fillings. Such fillings made of mineral or glass wool are inherently used in silencers started and have proven themselves there excellently. However, since such mineral or glass wool fillings due to the acidic media of the outflowing gases, their pH values under 2.5 are attacked, they cannot be used in such silencers.

Mar. has therefore for silencers that of acidic Media are flowed through, open-pored polyurethane foam is used as fillings, with the corresponding bulk density also has the required flow resistance. Show fillings made of such polyurethane foam however, the lack of poor age stability because the

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Foams are mixed with plasticizers that diffuse out *, so that the foam very soon crumbly and so that the filling becomes unusable. In addition, fillings made of such foams must be cut from blocks which leads to the fact that the corresponding fillings have an uneven bulk density. This in turn has Undefined flow velocities result.

By the invention, the object is to be solved to provide a Γ · ~~ silencer which is suitable in particular for flue gas desulphurization, which is therefore traversed by a relatively acidic medium whose pH-value is below 2.5.

In addition, the corresponding filling must of course be temperature ^-resistant up to about 120 ^{° C.}

This object can be achieved by the invention in that the fillings are resistant to acidic media There are synthetic fibers, the fiber diameter of which is between about 2 μια and about 20 μπι, the fibers so

C are that the length-specific flow resistance 4th

is at least three kNs / m.

With the proposal according to the invention, there is no need to forego the tried and tested fiber material and switch to foam materials, because it has been shown that, surprisingly, plastics resistant to acidic media, in particular polypropylene, can be drawn into fibers that are comparable in their fineness to mineral and glass wool fibers and can also be compressed to such an extent that a usable felt is created. The fillings made of the plastic fiber material can be in the form of bound felts or plates, the bulk density of which is between 30 and 200 kg / m ³ .

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The felts or panels can be made from binders

or fibers bound by sintering.

The drawing shows an exemplary embodiment of a silencer according to the invention of for example square cross-section.

With 1 the muffler housing is referred to, the to an inflow channel 2 via a conical part 3

v ~ - 'is connected and via cen conical part 4 in the

Outflow channel 5 merges. Ia housing part 1 are in Arranged longitudinally extending aisorption plates 6, which leave fanals 7 free between them, through which the outflowing medicine flows. In doing so, loses it transfers its sound energy to the absorption plates.

Another option, such a muffler to build, consists in providing built-in components that are covered with appropriate fillings. The construction of the silencer is known per se, so that further discussion is unnecessary.

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Claims (4)

Claims 1. Silencers, especially for flue gas desulphurisation systems, in the case of a channel through which the outflowing medium flows according to the absorption or resonance principle effective fillings are accommodated, characterized in that the fillings (6) consist of synthetic fibers resistant to acidic media, the fiber diameter of which is between approx 2 μπι and about 20 μπι lies, the fibers being compressed in this way are that the length-specific flow resistance is at least 3 kNs / m. 2. Silencer according to claim 1, characterized in that the fillings made of polypropylene fibers exist. 3. Silencer according to claim 1 or 2, characterized in that the filling made of the plastic fiber material is in the form of bonded felts or plates, the bulk density of which is between 30 and 200 kg / m ³ . 4. Silencer according to claim 3, characterized in that the felts or plates consist of fibers bound by binding agents or by sintering.