Abstract: The invention relates to a method for removing sulfur dioxide from a dry gas stream which comprises following steps: (a) adding a hydrogen-peroxide-comprising liquid to the gas stream, sulfuric acid forming from the hydrogen peroxide and the sulfur dioxide and (b) condensing, absorbing or aerosol precipitation of the sulfuric acid formed. The admixed hydrogen-peroxide-comprising liquid is mixed with the dry gas stream in the course of less than 0.3 s in such a manner that the admixed liquid is essentially homogeneously distributed in the gas stream. Furthermore, the invention relates to an apparatus for removing sulfur dioxide from a dry gas stream which comprises at least one atomizing nozzle for adding the hydrogen-peroxide-comprising liquid and a filter or aerosol separator, arranged downstream, in the direction of flow of the gas stream, of the at least one atomizing nozzle, in each case at least one atomizing nozzle being arranged on a cross sectional area of 300 to 350 cm2.

Abstract: A process, using regenerable adsorption materials, for purifying exhaust gases that have been contaminated with at least SO.sub.2, a heavy metal such as mercury and additional toxic gases such as dioxins and furans is disclosed. The process includes adsorbing the exhaust gases where the gas if freed of SO.sub.2, heavy metal and additional toxic gases, and optionally subjecting the gas from the adsorber to further treatment. The contaminated adsorber material is subjected to an oxygen-free regeneration process and the gas from the regeneration process is scrubbed and subsequently processed into pure sulfuric acid in a nitric oxide-sulphuric acid plant.

Abstract: A filling or packing body has an annular cell structure. All walls surrounding each cell are normal to the main plane along which the annular structure extends. Dividing walls between the cells transverse to an outer wall closed upon itself are parallel with each other at least for a row of adjacent cells or for all of them. The ring constituted by the row of cells having the outer wall in common can be of round, in particular of circular or elliptic configuration, or its configuration can be polygonal, especially triangular. The height of the cell walls, normal to the main plane, can be constant or it can be higher at the center than at the periphery of the ring structure.

Abstract: A process for recovering nitrobenzene, dichlorobenzene and/or trichlorobenzene from substantially undried exhaust gases or spent air containing these compounds, by passing said gases through a layer of silica-containing adsorbents and, after adsorption, regenerating the adsorbents by removing the sorbed compounds. The relative humidity of the waste vapors is preferably less than 50% in order to achieve an effective separation by adsorption.

Abstract: A gas scrubbing tower is described which has a top region, a sump region and at least two washing stages between these regions. The tower comprises gas entry means between the the sump region and the lowermost of the washing stages; gas exit means in the top region; a first washing stage, in the direction of gas flow through the tower, constituted by a layer of packing elements resting on supporting means in a cross-sectional plane; a first circulating line for wash liquid from the sump region to the layer of packing elements; a second, packing-free washing stage above the first washing stage; a second circulating line for conducting wash liquid through the second washing stage; a sludge separator, and conduit means for introducing water from outside the tower into a washing stage or into the sludge separator of the tower.A process for operating the scrubbing tower is also described.

Abstract: A process for purifying the off-gases from industrial furnaces and especially from waste incineration plants is described in which process the off-gases which contain acid, neutral and/or basic pollutants in the gaseous or solid form or in the form of a mist, are treated in an evaporative cooler and then in a dry purifier, in which they are freed from at least a substantial portion of the solid pollutants, and finally in a scrubber by means of a wash liquid. The temperature of the off-gases in the evaporative cooler is kept above the dew point, and the wash liquid in the scrubber is cycled through a slurry separator, from which suspension or solution of pollutants is withdrawn from the sludge separator and fed into the evaporative cooler and mixed in a mixing space in the latter with the hot off-gases.

Abstract: A process is described for separating SO.sub.2 from a current of gas containing the same, at least intermittently, in a concentration which is impermissibly high for discharge into the ambient atmosphere, with attendant production of sulfuric acid by the nitrogen oxide process, in which latter process the SO.sub.2 -containing gas initially flows through a dentriation zone, or first through a pretreatment zone forming a first sector of an SO.sub.2 -processinbg zone and then through the denitration zone, thereafter through the main sector of the SO.sub.2 -processing zone, and subsequently through a nitrogen oxide absorption zone, in the course of which flow it is brought into contact in at least one of the two sectors of the SO.sub.2 -processing zone with dilute acid having a H.sub.2 SO.sub.4 -concentration of less than 70% by weight (55.degree.

Abstract: A gas scrubbing plant having a gas scrubbing stage, a washing liquid separating stage and a stage for washing out suspended matter therebetween. This latter stage includes a plurality of gas baffles which accelerates the gas and then decelerates it while liquid is introduced into the gas baffles as the gas passes therethrough. Each baffle has an inner conical member surrounded by an outer member to define therebetween an annular passage with diverges at an angle of between 10.degree. and 90.degree. from the inlet adjacent the apex of the conical member to the outlet from the baffle, the cross-sectional area of the annular passage decreasing in the direction of gas flow and then increasing towards the outlet.

Abstract: Apparatus for the wet purification of gases, in which a wash liquid is sprayed into a gas to be purified and the gas is then forced or drawn through a separating wall having passage slots. The gas flow is divided up by pairs of such slots into pairs of sub-flows inside the wall, the sub-flows of each pair being rapidly accelerated to at least 30 m per second and then made to rebound on one another in a zone which is common to a pair of slots which causes them to be sharply deflected after which they separate and are decelerated. The sub-flows are accelerated by the passage slot construction which narrows inwardly from the exterior of the wall. Preferably two pairs of slots are provided, one pair converging into the wall and another pair diverging from the wall, both pairs opening into the common zone which is in the form of an X, the narrowest points of the slots being in said zone. The total area of the zones relative to the area of the wall is at maximum 15%.

Abstract: A process is described for separating SO.sub.2 from a moist current of gas containing the same, at least intermittently, in a concentration which is impermissibly high for discharge into the ambient atmosphere, with attendant production of a strong sulfuric acid by the nitrogen oxide process in a system of reaction zones, in which system the SO.sub.2 -containing gas flows successively through a denitration zone, thereafter through the SO.sub.2 -processing zone, and subsequently through a nitrogen oxide absorption zone, in the course of which flow it is brought into contact, at least in the SO.sub.2 -processing zone, with dilute acid having an H.sub.2 SO.sub.

Abstract: A packing material for liquid/gas contact reaction apparatus, in particular for gas purifying systems, which consists of a plurality of parallel rods arranged on a basket-shaped carrier and so dimensioned that it has an approximately spherical or spheroid form. The carrier consists preferably of parallel rings of staggered diameters. The packing material according to the invention has an extraordinarily high degree of efficiency and is very easy and relatively cheap to manufacture.

Abstract: A drop trap for a gas scrubbing plant, the trap having a plurality of parallel spaced apart corrugated plates forming channels through which gas flows and baffles at the downstream side of the corrugated plates to impart a downward velocity to liquid particles entrained in the gas flowing through the channels. Further baffles may be located at the upstream side of the corrugated plates to deflect the liquid particles downwardly to flow over the corrugated plates as they are separated from the gas as it passes through the channels. A method is also disclosed of rinsing the corrugated plates by intermittently spraying a predetermined quantity of liquid over the upstream side of the plates.