DE10014565A1 - Water-soluble malodorous substances removed from process air by atomized water droplets in presence of ultrasonic emissions - Google Patents

Abstract

In a process to remove pollutants and unpleasant odors from effluent gases, the gas is especially surrendered to and widely dispersed within an enclosed chamber or passage subjected to ultrasonic emissions. Atomized water droplets or active chemical substances (acids, alkalis, polymers) are also released into the chamber or passage and present a large droplet surface area to the effluent gases. Under the ultrasonic agitation, water soluble substances are taken up by the aqueous phase and are separated from the gases. The ultrasonic emitter is located within the enclosed chamber or passage and in any other passages or chambers through which untreated effluent gases flow. The atomized water or fluids move repeatedly through a closed circuit until saturated.

Description

The invention relates to a method for reducing the pollutant or odor content of exhaust air / exhaust gases.

The aim of the invention is to develop a method for cleaning of exhaust air / exhaust gases by adding to the exhaust gas stream, preferably with an odor is loaded with intensive substances, ultrasound atomized water or chemically active liquids (acids, alkalis, polymers) are introduced, that bind the odor or pollutants and thereby the exhaust gas odor or Make it pollutant-free.

For the industrial cleaning of exhaust air streams laden with organic pollutants and general odor emissions, the following processes are currently used:

• - thermal afterburning
• - catalytic afterburning
• - absorption
• - adsorption
• - biological exhaust air purification (bio filter and bio washer),

During thermal post-combustion (TNV), the air pollutants are removed Temperatures of 600-1000 ° C burned.

Due to the solid body used in catalytic afterburning (KNV) per-catalyst, the combustion temperature of the air pollutants can reach 250- 500 ° C can be reduced.

The principle of the process of adsorptive exhaust air purification is the addition the pollutants to porous adsorbents with a large inner surface (e.g. Activated carbon, zeolites, silica gel).  

The biological pollutants are oxidized in biological exhaust air purification systems through microorganisms.

The adsorption processes come from the proposed process of exhaust air / Exhaust gas cleaning with ultrasonic atomizing cleaning liquids at the next most. The prior art is therefore considered in more detail.

Absorption processes are based on the solution of the air pollutant in one liquid absorbent.

Spray, packing or tray columns are usually used for air purification Use in which the air to be cleaned is in intensive contact with the washing liquid liquid is brought.

Since the process works at normal temperature, it is characterized by a relatively low energy consumption.

Is there a separation of contaminants and after absorption Washing liquid with suitable mechanical or thermal processes, so solvent recovery is possible.

Since the absorbent requirement depends on the gas volume flow, but, except for very poorly soluble contaminants, regardless of the pollutant concentration tration is in the air, absorption processes are just with little damage substance concentrations can only be used very little effectively.

Absorption systems are also unsuitable for mixtures of pollutants (Much mixtures of substances) and time-varying contaminants, on the one hand because of the mostly selective effect of the absorbent and on the other hand due to the unacceptably high equipment and energy expenditure for the separation of Pollutants and washing liquid.  

If recovery is not planned (e.g. multicomponent mixtures, odor emissions ) there are wastewater and disposal problems because the washing liquid are contaminated with the pollutants. The temperature is too high air above 60 ° C, the absorption stage is a separate exhaust gas cooling upstream, which results in an increase in investment and operating co most impact.

To remove contamination down to the slightest residual content is often very high number of plates required.

This is associated with a high space requirement of the plants as well as high investments on costs. In some applications, the number of isolators is reduced add neutralizing substances to the washing liquid (Lau genes or acids).

However, the resulting reaction products are often wastewater pollutants and must be neutralized using additional reactants. It is no longer possible to recover the contaminants.

In most cases, however, organic solvents cannot be replaced by a acidic or alkaline air washes are removed from the exhaust air.

Absorption processes for exhaust air purification can advantageously be used anywhere there wherever solvent recovery is economical and ecological is useful or absorbents and contaminants or reaction products are harmless as wastewater ingredients.

Another disadvantage of the known technical solutions is that the Exhaust gases are not at normal temperature and higher pollutant concentrations have ions.

The object of the invention is to provide a method for reducing the pollutant or To create odor content of exhaust air / exhaust gases, which has the disadvantages the known technical solutions.  

According to the invention, the object is and is to be solved by claims 1-4 are explained in more detail below.

According to the exhaust gas in a closed chamber or Channel in which water is ultrasonically fined by a device is distributed.

The finely distributed water represents a large surface over which che water-soluble pollutants and odors in the aqueous phase and are thus withdrawn from the gas flow. The ones with smell or Water droplets laden with pollutants are preferred from the gas stream removed by gravity or mechanical devices.

The fine distribution of the water is done by feeding the water to egg NEN ultrasonic beam, preferably on its quick button ten.

The polluted water must be disposed of as wastewater. Depending on the Bela The exhaust gas and water can be recycled.

The technical and economic advantages to be achieved are as follows:

By treatment with this method in suitable facilities the odor intensive and pollutants removed from the exhaust gas flow. Thereby cleaning is achieved and the release into the ambient air can be done without Pro bleme done.

The solution according to the invention is thus a contribution to compliance with the techni rules and norms of environmental protection.

The economic advantage is that the treatment of the exhaust gases is an Ab guidance into the ambient air is possible without conflicting with the requirements of the Environmental agencies to come.

The exhaust gas purification according to the method described is preferably small systems economically favorable.  

The ancestor according to the invention will now be presented with reference to Fig. 1 Darge.

Air is pressed into the device for pollutant loading ( 2 ) by means of a blower ( 1 ). The air loaded with pollutants / odorous substances is led through the horizontally arranged path ( 3 ), in which the oscillating beam excited by an ultrasound processor is located. This bar is continuously subjected to the appropriate amount of liquid to be atomized from the outside.

The air loaded with water or reactive mists is fed to the liquid separator ( 5 ) after passing through a reaction line ( 4 ). The loaded liquid should be collected in a container ( 6 ).

The cleaned exhaust air should be released into the atmosphere via line ( 7 ).

Claims (4)

1. A method for reducing odor and pollutant emissions, characterized in that the exhaust gas in a closed chamber or a channel and is distributed in this way that the finely divided water represents a large surface, over which water-soluble pollutants and odorous substances be taken up in the aqueous phase and thus withdrawn from the gas stream and the water droplets laden with odors or pollutants are removed from the gas stream and the water is guided to ultrafine distribution on a beam vibrating with ultrasound 2. The method according to claim 1, characterized in that the ultrasonic device device is arranged directly in the exhaust duct. 3. The method according to claim 1, characterized in that the ultrasonic on Direction is arranged in the chambers through which the exhaust gas / exhaust air flows. 4. The method according to claim 1, characterized in that the atomized water / the atomized liquid is circulated until saturation.