FI109098B - Acoustic cleaning device and method - Google Patents

Description

109098

Acoustic Cleaning Apparatus and Method Anordning och forfarande för akustisk rengöring 5

The invention relates to an apparatus and method for acoustic cleaning.

Acoustic cleaning, also called acoustic cleaning, is a method used for e.g. for cleaning boilers, silos, cyclones, fans, filtration equipment, etc. The acoustic cleaning method is useful in applications where, for example, powdered materials are processed or where by-products such as soot or dust are generated. Such particles readily form aggregates which impede the flow of the process and impair its functionality.

The advantage of acoustic cleaning over the various mechanical cleaning methods is the ability to operate without interrupting the process. Another significant. .y may mention the advantage of the method's ability to clean also shadows and other i * *; ·. 20 hard-to-access items. The method does not consume cleaning objects, is easy to use. * Workable and have low maintenance costs.

. "*. In acoustic cleaning, a sound wave is applied to the object to be cleaned, which transmits a pressure stroke to the removable particles. To achieve a cleaning result, the force transmitted by each 25 sound pressure pulses to each particle must be greater:": than the

* ··. Acoustic cleaning devices are known e.g. WO-82/01328 and WO-82/03803.

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In an acoustic cleaner, the typical duration of a sound pressure pulse is a few seconds and these pulses are given every 2 to 15 minutes. A typical basic sound frequency is 20-360 Hz and the sound pressure level is typically 130-200 dB.

A method for generating a sound pressure pulse is known in which a fuel mixture is introduced into the combustion chamber which is exploded. Such an arrangement is known from SU-871186. Such arrangements involve safety risks from the use of highly flammable fuels 10 in a hot power plant environment. In addition, an explosion impulse can break the acoustic cleaner fuel lines, causing a risk of fire or explosion. A further problem is the relatively slow combustion in the long cylindrical combustion chamber.

It is an object of the present invention to solve the problems encountered in prior art arrangements and to provide a safer and more efficient device and method for generating acoustic pressure pulses for acoustic cleaning.

·. The device according to the present invention is essentially characterized by the fact that ·; ·. The apparatus 20 is provided with an electrolysis unit for producing fuel electrolyte. and for use in a combustion chamber for explosive combustion.

The process according to the invention, in turn, is characterized in that the method comprises providing the acoustic cleaning device with an electrolysis unit, electrolytically producing the fuel 25 in the electrolysis unit, supplying the fuel to the combustion chamber and activating the fuel chamber lighters.

In the arrangement of the present invention, generating a sound pressure pulse . "'; the fuel gases used in connection with the acoustic cleaner are electrolytically produced using water as the raw material and, for example, as a raw material electrolyte, such as potassium hydroxide or other inorganic salt. Such an arrangement does not require 3 109098 separate fuel stores. there is no problem with storage, and clean water is also produced as a product of combustion to produce a sound pressure pulse, which is environmentally beneficial.

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In the following, the invention will be explained in more detail with reference to the accompanying drawing, which shows an operating diagram of an acoustic cleaning device according to the invention.

The acoustic purification apparatus 10 comprises a combustion chamber 11, an acoustic horn 12, a power supply 13, a timer 14, an electrolysis unit 15 and a voltage source 16. The water is supplied along line L1 to an electrolysis unit 15 using a suitable electrolyte, e.g. The separation of water from oxygen is accomplished by the electrolysis unit 15 when a voltage difference from a voltage source 15 is coupled between the positive and negative poles.

The combustion chamber 11 is provided with igniters SP whose activation by the timer 14 causes an explosive combustion event to be initiated. There may be one or more lighters SP. By using more, preferably three or more, lighter SPs, a smoother combustion event is achieved. According to the invention; ; · In 20 arrangements, combustion is fast and complete, producing * * pure water as a combustion product.

• *. In a preferred embodiment of the invention, the combustion chamber 11 is provided with a pressure nipple 17 capable of monitoring the state of the combustion chamber 11 and detecting a combustion event following successful ignition.

: After each successful ignition, the circuit of the electrolysis unit 15 is reactivated. If the ignition of the spark does not trigger a new combustion, ···. event, the automatic security system of the device 10 shuts off the device 10 ', 30 and issues an alarm message.

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The acoustic cleaning device of the present invention may further be provided with safety automation that prevents operation of the device e.g. This avoids possible dust explosions in the cold.

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The following are claims which are not intended to be limited solely by the invention.

Claims (7)

5, 109098 Apparatus for acoustic cleaning comprising a combustion chamber (11), a horn (12), a fuel supply line (L2) and one or more lighters 5 (SP) for igniting fuel, characterized in that the device (10) is provided with an electrolysis unit (15) for electrolytically producing fuel and for use in the combustion chamber (11) for explosive combustion. Device according to Claim 1, characterized in that the electrolysis unit 10 (15) is arranged to produce fuel from water in the presence of an electrolyte. Device according to Claim 1 or 2, characterized in that the electrolyte is potassium hydroxide or other inorganic salt. Method for acoustic cleaning, characterized in that: the acoustic cleaning device (10) is provided with an electrolysis unit (15), the fuel is produced electrolytically in the electrolysis unit (15), the fuel is led along the fuel line (L2) to the combustion chamber (11); (SP) is activated. '. : * ·. 20 Method according to Claim 4, characterized in that the electro. '·. the lysis unit (15) is activated after successful combustion. A method according to claim 4 or 5, characterized in that the device 25 (10) is provided with a security automation which prevents the device (10) from being used when the object to be cleaned is out of normal use. ,:. Method according to one of Claims 4 to 6, characterized in that is-. '. a detonated combustion event is detected by a pressure sensor (17). 30 6 109098