METHOD OF AND APPARATUS FOR OXIDATIVE TREATMENT OF LIQUID, GASEOUS, AND/OR SOLID PHASE

Abstract

The invention relates to a method and a device (100) which are provided for the oxidative treatment of a liquid phase and/or a gas phase and/or a solid phase. According to the invention, ozone and at least one component, which is provided by the ozonization of at least one olefin, is used for the treatment. The method and the device can, for example, be used for waste water treatment.

Claims

1. A method of oxidative treatment of a liquid, gas or solid phase, the method comprising the step of: using ozone and at least one organic ozonide for the treatment.

2. The method according to claim 1, wherein the method is carried out in the presence of water.

3. (canceled)

4. The method according to claim 1, further comprising the step of: adsorbing the organic ozonide with a packing.

5. The method according to wherein the liquid phase is contaminated water, the method further comprising the step of: ionizing the water and treating the ionized water with the at least one organic ozonide.

6. The method according to claim 5, further comprising the step, for the treatment of the exhaust air from the method, of treating the exhaust air with at least one organic ozonide, and wherein the exhaust air is preferably ozonized.

7. The method according to claim 1, wherein the gas phase is an exhaust gas.

8. The method according to claim 1, wherein the solid phase is formed by inner surfaces of wooden barrels or tanks.

9. The method according to claim 1, the solid phase is formed by waste, the method further comprising the step of: comminuting the waste before the oxidative treatment.

10. An apparatus for oxidative treatment of a liquid, a gas or a solid phase, the apparatus comprising: means for introducing ozone; and means for introducing an organic ozonide.

11. The apparatus according to claim 10, further comprising: a packing for adsorption of the component resulting from ozonizing the at least one olefin and comprised of pebbles or materials consisting of metal oxides or ceramic or glass, and having oxidic surfaces.

12. The apparatus according to claim 10, at least one wherein the means for introducing a organic ozonide is provided in an exhaust-air line of the apparatus.

13. The apparatus according to claim 10, further comprising: means for introducing ozone or means for moistening the stream of air in an exhaust-air line of the apparatus.

14. The apparatus according to claim 10, wherein the apparatus is configured for oxidative treatment of contaminated water, and the means for introducing ozone is an arrangement for ozonizing the water.

15. The apparatus according to claim 10, wherein the apparatus is configured for oxidative treatment of exhaust gases or exhaust air, and the means for introducing ozone is an arrangement for ozonizing the exhaust gases or the exhaust air.

16. The apparatus according to claim 10, wherein the apparatus is configured for oxidative treatment of solid materials, and further comprises: means for moistening the solid materials.

17. The apparatus according to claim 16, wherein the apparatus is configured for oxidative treatment of inner surfaces of wooden barrels, or tanks.

18. The apparatus according to claim 16, wherein the apparatus is configured for oxidative treatment of waste, and further comprises: means for comminuting the waste before or during the oxidative treatment.

19. An evaporative cooler further comprising: means for introducing ozone, and means for introducing a organic ozonide, into the evaporative cooler.

Description

[0067] In the drawings:

[0068] FIG. 1 shows a first embodiment of an apparatus according to the invention for the oxidative treatment of contaminated water;

[0069] FIG. 2 shows a second embodiment of an apparatus according to the invention for the oxidative treatment of contaminated water;

[0070] FIG. 3 shows a third embodiment of an apparatus according to the invention for the oxidative treatment of contaminated water;

[0071] FIG. 4 shows a fourth embodiment of an apparatus according to the invention for the oxidative treatment of contaminated water with additional exhaust air treatment;

[0072] FIG. 5 shows an embodiment of an apparatus according to the invention for the oxidative treatment of comminuted solid materials;

[0073] FIG. 6 shows an embodiment of an apparatus according to the invention for the oxidative treatment of barrels or tanks; and

[0074] FIG. 7 shows an embodiment of an evaporative cooler according to the invention.

[0075] FIG. 1 shows a first embodiment of an apparatus 100 according to the invention for the oxidative treatment of contaminated water. Essential components of the apparatus are an ozone generator 101 and a unit 102 by which an ozonide substance, in particular organic ozonides (and/or peroxides and/or hydroperoxides), are provided. A tank 103 stores dry oxygen introduced into the ozone generator 101. The oxygen serves as carrier gas for the ozone formation in the ozone generator 101, and the ozone is produced in particular electrically by plasma discharge in a manner known per se. The ozone formed is introduced into a tube reactor 105 by an ozone metering point 104 preferably equipped with a fine filter (frit). The tube reactor 105 is located in a reaction tank 106. The water to be treated is conveyed by a pump 107 into water inlet tanks 108 and introduced into the tube reactor 105. The water to be treated runs through the tube reactor 105 and is admixed with ozone in the metering point 104. The gaseous ozone is dissolved in the aqueous phase. Turbulent flow conditions that promote efficient dissolving of gas preferably prevail in the tube reactor 105. In this case the ozone can react directly for example with aliphatic harmful substances as well as with bacterial substances, in particular with proteins and lipids, and produce a first oxidative treatment stage. Further along the tube reactor 105 is located a metering point 109 for the organic ozonide or the ozonide substance. The ozonide arrives by a pump 110, for example a geared pump, at the metering point 109 and is for example added drop by drop.

[0076] In this example the starting material for the ozonide production in the unit 102 is a mono- or polyunsaturated fatty acid, in particular oleic acid provided in the form of virgin olive oil in the storage container 111. The ozonide forms in the unit 102 aprotically according to the Criegee mechanism, and dry ozone gas from the ozone generator 101 serves as carrier gas. The ozonide (ozonized olive oil) forms a pasty or creamy substance introduced into the tube reactor 105 by the geared pump 110. In other embodiments it may be provided that the ozonide is produced at another location and as a prepared ozonide substance is transported to the installation and is used there.

[0077] For the ozonide production the ozone gas is introduced into the substance to be ozonized, that is to say for example into the virgin olive oil. In this case the concentration of the ozone gas may be for example 120 g O.sub.3/m.sup.3 O.sub.2. Depending on the layout of the installation the ozonide production may be completed after approximately 2 to 8 hours. The successful ozonization process can be monitored in particular with reference to the consistency and the coloring of the resulting compound that in the course of the ozonization becomes increasingly pasty and whitish. The resulting ozonide has a very high content of peroxide compounds. The peroxide value can be for example between approximately 300 and 1000 or higher, in particular up to 6000.

[0078] Downstream of the metering point 109, in the tube reactor 105 there is a region 112 that contains a packing on which the ozonide substance, which is only just water-soluble, is adsorbed. This packing preferably consists of pebbles or other structures, for example consisting of metal oxide or ceramic materials or of glass that are suitable for adsorption of the ozonide substance. Due to the adsorption of the ozonide substance there are always traces of ozonide or other peroxide compounds available for the oxidative reactions. Particularly advantageously, the adsorption materials have oxidic surfaces on which a further conversion of the ozone dissolved in the water takes place. Metal oxides or ceramics are suitable in particular for process management at pH values above 7, and for example aluminum oxide or manganese oxide can be used. Further suitable materials are for example silicon oxide (silica gel) or porous glass.

[0079] The high outflow speed from the tube reactor 105 leads to a circulating movement in the reaction tank 106, indicated here by broken-line arrows. Due to the delivery capacity of the pump 107 an overflow is produced in the region 114, and the water is directed into an overflow tank 115. An arrangement 116 for UV irradiation of the water is provided in the overflow tank 115. In this region excess hydrogen peroxide is destroyed by the UV irradiation. The overflowing ultrapure water enters the ultrapure water conduit 117 as the outlet of the apparatus 100. The water in the ultrapure water conduit 117 is continuously measured with regard to ozone and hydrogen-peroxide concentration. For this purpose a sensor 118 for hydrogen peroxide and a sensor 119 for ozone are provided. A further hydrogen peroxide measurement can also take place in particular in the overflow 114 between the reaction tank 106 and the overflow tank 115. On the basis of the process parameters recorded by these measurements, control and/or regulation of the metering of ozone and/or ozone production take place in the ozone generator 101. For this purpose a control and/or regulating unit not illustrated in greater detail is provided, so that the ozone production and/or the metering of ozone can be regulated or controlled according to consumption. Excess ozone gas emanating from the water can be thermally eliminated by an ozone destroyer 121 provided above the ultrapure water conduit 117.

[0080] A pH value measuring unit 120 is provided at the water inlet 108. This unit records the pH value of the introduced water. Since the method according to the invention is preferably carried out in a basic environment, in particular at a pH value of 7 or higher, in particular at pH 8 or higher, the pH value is optionally set to a suitable pH value.

[0081] FIG. 2 illustrates a further embodiment of an apparatus 200 for oxidative water treatment. An ozone generator 201 and a unit 202 for providing the ozonide substance are provided in a manner comparable to the embodiment according to FIG. 1. Dry oxygen stored in the container 203 is used as carrier gas for the ozone production in the ozone generator 201. Also in this example ionizing of unsaturated fatty acids takes place in the unit 202 using oleic acid held ready in the storage container 211 in the form of virgin olive oil.

[0082] In this embodiment, particular emphasis is placed on the water treatment in the direct ozone reaction that in particular also effects disinfection or sterilization of the water to be treated. This embodiment therefore differs from the example illustrated in FIG. 1 by the measures for introducing the ozone gas into the water. The water to be treated with the harmful substances it contains is conveyed from a well 222 by a feed pump 223 and reaches a metering point 204 for the ozone by a pipeline 224. In this embodiment the metering point 204 is configured as an injector located above the water level of the reaction tank 206. The injector 204 is designed in the form of a Venturi nozzle, so that at the injector outlet a counter-pressure is generated that produces an increase in the water solubility of the ozone gas. This is followed by a turbulent pipe section 225 that opens into the inlet tank 208. In this case the turbulent pipe section 225 is for example at least 10 m long. This pipe section 225 is configured so that substantial turbulence is produced (Reynolds number>5000). Due to this measure optimal dissolution of the ozone gas in the water is achieved. Measurements have shown for example that the gas bubbles that rise up in the inlet tank 208 are ozone-free.

[0083] A unit 220 for measuring and if applicable regulating the pH value is located in the inlet tank 208. The pH value is preferably set in a basic range. A unit 212 for measuring and, if applicable, regulating the pH value is located in the inlet tank 208. The packing 212 consists for example of a pebble bed or of metal oxide or ceramic materials. The packing preferably has oxidic surfaces, so that here too conversion of the ozone can take place. The metering point 209 for the ozonide substance is located in the inlet tank 208. The ozonide substance is for example introduced as an oily or creamy substance into the tank 208 by a geared pump 210. The ozonide substance is virtually water-insoluble and is adsorbed on the packing 212. A circulation pump 207 that draws the water through the packing 212 and feeds it into a tube reactor 205 is located in the inlet tank 208. In this case the pumped volume of the circulation pump 207 is greater than the pump volume of the feed pump 223. A further region with a packing 232 for the adsorption of the ozonide substance is provided in the downstream region of the tube reactor 205. Due to the high outflow speed from the tube reactor 205, a circulating movement takes place in the reaction tank 206 so that the substances (contaminants) contained in the water can be completely oxidized and decomposed.

[0084] An overflow 214 for the treated water is provided and opens into an overflow tank 215, in a comparable manner to the embodiment of the apparatus according to FIG. 1. A further overflow 226 for the water from the reaction tank 206 is located between the reaction tank 206 and the inlet tank 208, so that the overflowing water passes through the packing 212 a number of times.

[0085] An excess of hydrogen peroxide can occur in the reaction tank 206 due to the oxidative processes being performed. The hydrogen peroxide promotes the decomposition processes and is therefore advantageous. The hydrogen peroxide can be recirculated through the overflow 226, so that it is uniformly available. In this case it is particularly advantageous that no external hydrogen peroxide has to be metered in, so that the potentially dangerous storage and metering of hydrogen peroxide is omitted in an installation according to the invention. If the hydrogen peroxide concentration is too high, the metering of ozone can be throttled.

[0086] An arrangement 216 for UV irradiation of the water is provided in the overflow tank 215, so that excess hydrogen peroxide can be decomposed before it leaves the installation. Downstream of the overflow tank 215 the water then reaches the ultrapure water conduit 217 by a further overflow. Here and, if applicable, in the overflow 214 a hydrogen peroxide measurement 218 and an ozone measurement 219 can take place. The measured values are used for controlling and/or regulating the addition of ozone and/or the ozone production. The measured values of the hydrogen peroxide concentration at the overflow 214 can also be used for controlling the UV treatment in the tank 215. Excess ozone gas emanating from the water can be eliminated by an ozone destroyer 221.

[0087] FIG. 3 shows a further example for a preferred embodiment of the apparatus 300 according to the invention for the oxidative treatment of contaminated water. The apparatus 300 is substantially comparable to the embodiment 200 that has been explained with reference to FIG. 2. In contrast, the embodiment 300 has a further UV radiation source 326 in the downstream region of the tube reactor 305. The UV lamp 326 is located downstream of the packing 332 provided for adsorption of the ozonide substance. Due to the UV irradiation in the tube reactor the formation of hydroxyl radicals from hydrogen peroxide is further intensified, so that due to the UV irradiation at this position the oxidative decomposition of harmful substances is further improved.

[0088] With the method according to the invention, which can be carried out in particular by the described apparatuses, above all organic contaminated water can be processed very effectively. Compared to an ozone treatment, as is known per se, the method according to the invention, in which the additional oxidizing component on the basis of ozonized fatty acid is used, enables a substantially more extensive decomposition and a mineralization of the organic substances contained in the water, and in particular also a decomposition of halogenated organic hydrocarbons and other trace pollutants. The oxidative decomposition or purification process according to the invention is based on a radical chain reaction, and hydroxyl radicals are the crucial molecules. Due to the combination of ionizing the water with a treatment with the component on the basis of ozonized fatty acids different sources are available for the hydroxyl radical formation, which influence each other, so that precisely this combination causes the very effective oxidative treatment. In this case, in particular, organic ozonides are the initiators of the radical chain reaction. On contact with the water, the substantially water-insoluble ozonide decomposes into the aldehyde and carboxylic acid fractions, and hydrogen peroxide is formed (equation G8). In the presence of ozone, ultimately the hydroxyl radical forms according to the following equations, and the equation G7 describes the reaction constant for the reaction of the anion with ozone in order to form the hydroxyl radical dependent upon the pH value and the pKa value.

##STR00003##

[0089] Thus, for the formation of the hydroperoxide anion as precursor of the hydroxyl radical, to start with there are two sources, namely from the decomposition of ozone (equation G1, see above) and from the decomposition of the ozonide (equation G8), in particular at basic pH values. Also the carboxylic acid produced from the organic ozonide can also, as intermediary in the entire system, is part of the radical chain reaction (ROO.) and can constitute a further source for the hydroxyl radical-formation. The oxidic surfaces of the packing materials at which ozone can be converted can act in the apparatus according to the invention as a further source for the hydroxyl radical formation. A further source for the hydroxyl radical formation can be achieved by the UV irradiation in the reaction tank, and hydrogen peroxide is converted to the hydroxyl radical by UV action.

[0090] Measurements show that after treatment with the ozonide substance according to the invention no more ozone can be detected in the treated water. Hydrogen peroxide can only be measured when there is no longer any possibility of reaction of the hydrogen peroxide, in other words when the organic substances contained in the water are completely decomposed. This is the case above all at a pH value of 8.4 or more. At pH values below 8, for example at pH 7.9, it may still be possible to measure ozone and hydrogen peroxide. The effect of the pK.sub.a value (equation G7a) on the stability of the ozone vanishes due to the presence of ozonide. Over-metering of ozone in the presence of the aprotically produced ozonide then leads to a rise in the hydrogen peroxide content. This excess hydrogen peroxide can be eliminated, if required, by UV irradiation.

[0091] FIG. 4 illustrates a further configuration of the apparatus 400 according to the invention, in which in addition to the oxidative water treatment a more far-reaching treatment of the exhaust air from the system is provided. FIG. 4 shows in the lower part the apparatus for the actual water treatment that corresponds substantially to the embodiment shown in FIG. 1. The exhaust-air line of the installation is shown in the upper part of the illustration. During the waste-water treatment odor emissions are often produced that are attributable in particular to sulfur compounds (for example hydrogen sulfide, mercaptans). According to the invention these highly odorous compounds are eliminated by gas scrubbing and/or by an oxidative treatment in the exhaust-air line. The exhaust air from the water treatment, illustrated here by the arrow 429, is fed into the following exhaust gas system by a fan 422. First of all the exhaust gas runs through a gas scrubber 423. The gas scrubber 423 is supplied by a pump 431 with water from the reaction tank 406 that serves as the washing fluid in the gas scrubber 423 This water contains hydrogen peroxide as a result of the oxidative processes during the water treatment. The hydrogen peroxide that enters the exhaust-air line in this way promotes the oxidative processes during the exhaust-gas treatment. After the gas scrubbing the exhaust gas enters a region with a packing 424 provided for the absorption of ozonide and/or other peroxide compositions that are supplied by ozonizing unsaturated fatty acids. This oxidizing component is introduced in liquid or in gaseous form into the exhaust-air line via the metering point 427. This oxidizing component is conveyed, for example in the form of an ozonide-containing gas, by a gas pump 432 out of the unit 402 provided for supplying the ozonide substance for the water treatment. Liquids and condensates from the gas scrubber 423 and from the region with the packing 424 run via a drainage line 430 back into the tank(s) of the waste-water treatment system. In this example the liquids run back into the water inlet tank 408. Due to the products formed during the oxidative treatment, in particular SO.sub.2, the condensate is generally acidic, depending upon the contamination of the exhaust air. Therefore, it can also be used for adjusting the pH value in the installation. For example, the pH value of the water running out can be adjusted or neutralized by the condensate, by introduction of the condensate into the ultrapure water conduit 417. If necessary, the SO.sub.2 formed during the oxidative treatment can be washed out by a further gas scrubber. The purified exhaust air can be released by the outlet 426.

[0092] Ozone can be metered into the exhaust-air line by the ozone metering point 428 in the fan 422. This ozone originates from the ozone generator 401 of the water treatment plant. Alternatively or additionally, for example, the ozone-containing exhaust air from the ozone destroyer 421 can be fed into the exhaust gas system. In such an embodiment the ozone destroyer 421 may possibly be omitted. In principle the basis for the exhaust air treatment according to the invention is that the exhaust gas in the form of moist ozone gas passes through a surface with ozonide and/or other peroxide compounds. In this case the moistening of the exhaust gas enriched with ozone is preferably resulting from gas scrubbing, and the gas scrubber is operated with peroxide-containing water from the water treatment.

[0093] FIG. 5 shows an embodiment of an apparatus 500 for treatment according to the invention of solid materials that are comminuted in this example. These materials may be in particular shredded waste, for example hospital waste. Comminuted waste 524 is introduced into a treatment container 533 by a conveyor belt 532. The inlet and the outlet of the treatment container 533 can be closed by respective valves 536 and 537. A moistened stream of air enriched with ozone and with ozonide flows through the treatment container 533. For this purpose an ozone metering point 528 is provided in the air supply 529 to the apparatus 500, and the inflowing air is enriched with ozone. The air 529 supplied to the apparatus is propelled by a fan 522. The stream of air runs through a moistening unit 523. Water nozzles 538 that atomize water are provided in the moistening unit 523. The water nozzles 538 are fed by a water system 539 supplied by a pump 534. The stream of air enriched with ozone and moistened then passes a metering point 527 for ozonide. In this case the air stream is additionally treated with ozone or generally with at least one component resulting from ionizing at least one olefin. This oxidizing component can be introduced in liquid or in gaseous form. Then the stream of air enters the treatment container 533 with the waste to be treated. The accompanying ozonide component is adsorbed on the solid materials and the described oxidative processes can proceed in the prevailing moist medium. The waste 524′ treated in this way is ejected by the valves 537 at the outlet of the container 533 and can be transported away by a conveyor belt 540. Excess liquid in the treatment container 533 collects at a water outlet 541 of the treatment container 533 and is returned to the water system 539. After running through the container 533 the air leaves the apparatus through an exhaust-air opening 526.

[0094] The water in the water system 539 cools due to the evaporation of the water in the moistening unit 523. This cooling by evaporation can be used with a heat exchanger 535 in order to cool other media (indirect evaporative cooler). Furthermore, the heating of the water that occurs in this case in the water system 539 is advantageous for the effective moistening of the stream of air in the moistening unit 523.

[0095] As an alternative to the treatment container 533 shown in FIG. 5 and the conveyor belts 532 and 540, continuous operation with a cyclone is for example also possible in a comparable manner.

[0096] FIG. 6 illustrates an apparatus 600 according to the invention for oxidative (sterilizing) treatment of the inner surfaces of wine barrels 603 or of tanks on the basis of the method according to the invention. The barrels 603 or tanks to be cleaned are supported on a storage rack 601 with positioning rollers 602. A spray head 604 projects into the interior of the barrels 603 through a corresponding opening in the barrels 603 or tanks. In the course of the treatment an ozonide substance is sprayed by the spray head 604 into the barrel 603 or tank. Then, simultaneously or beforehand, ozone water, that is to say water admixed with ozone, or ozone gas is introduced via the spray head 604 into the interior of the barrel 603 or of the tank. For this purpose the spray head 604 is connected by a hose connection 605 as supply conduit with a supply unit 606. By means of the supply unit 606 the provision and the delivery of ozonized water (or ozone gas) and the ozonide substance take place via the hose connection 605. Fresh water is supplied to the supply unit 606 by a fresh water supply 607. A collecting tank 608 for liquids from the barrels 603 or tanks is provided in the lower region of the storage rack 601. As soon as the oxidative processes within the barrels 603 or tanks are concluded, the liquid contained in the barrels 603 or tanks can be drawn off by a suction extraction element 609 and collected in the collecting tank 608. The liquid from the collecting tank 608 is directed by a hose connection 610 as discharge conduit into the supply unit 606 and from there is discharged via an outlet 611 into a discharge conduit 612. The resulting exhaust gases can also be discharged by a ventilation conduit 613.

[0097] FIG. 7 shows an evaporative cooler 700 according to the invention provided for cooling a stream of air. This evaporative cooler may for example be a component of an air-conditioning system. The stream of air is indicated by arrows 729 and 726, and the air enters the evaporative cooler 700 from an air supply 729 and leaves the evaporative cooler 700 by the air outlet 726. In this case the air runs through a packing 733, for example a plastic packing. The packing 733 is sprayed with water by a plurality of nozzles 738, so that the packing 733 is wetted with moisture. Due to the evaporation of the water in particular in the packing 733, a cooling effect is achieved for the air flowing through the packing 733. The evaporation of the water can be supported by a fan 722. In the lower region of the evaporative cooler is a water container 741 for collecting excess liquid. The water container 741 is part of a water system 739 supplied by a pump 734 and feeds the nozzles 738. Due to the evaporation of water in the packing 733, that is to say within the water system 739, the circulating water cools and can be used for cooling purposes for a heat exchanger 735. For the oxidative treatment of the evaporative cooler 700 according to the invention, on the one hand an ozone metering point 728 is provided for feeding ozone gas or ozonized water into the stream of air. On the other hand an ozonide metering point 727 is provided for the substance formed by ionizing at least one olefin, that is to say for the ozonide substance, and in the embodiment illustrated here the ozonide substance is fed into the water system and is distributed on the packing 733 by the nozzles 738. The combined treatment with ozone and ozonide leads to the described oxidative processes and chain reactions and thus to sanitization of the evaporative cooler 700, so that bacterial contamination and algae growth in particular in the packing 733 is reliably avoided and a clean and simultaneously cooled stream of air is achieved.