Method and device for reduction of carbon monoxide and halogenated organic compounds in garbage incineration plants

FIELD: technological processes.

SUBSTANCE: invention may be used in garbage incineration plants in various industries. Gaseous wastes produced in combustion chamber 1, 3 and cooled in jacket 5 are supplied into dust arrester 7, and then in the first scrubber 8. In scrubber 8 via pipeline 19 water is supplied, and hydrochloric acid is discharged via pipeline 16. Partially cleaned gases are sent into the second scrubber 9, where selective cleaning of sulfur dioxide SO2 is carried out with the help of supplied ammonia solution 12. Produced aqueous solution of ammonium sulfate/sulfite is fully or partially returned to combustion chamber.

EFFECT: simultaneous reduction of carbon monoxide, halogenated organic compounds and nitrogen oxides NOx.

4 cl, 5 dwg, 1 ex

 

The invention relates to a method and apparatus for reducing carbon monoxide and halogenated organic compounds in waste incineration plants with at least one combustion chamber according to the first and fifth claims. Method and device suitable next equally to reduce corrosion of the casing by reducing the chloride content in fly ash arising from the work and forming deposits on the surfaces of boilers.

The combustion processes in which burned combustible substances containing sulphur, nitrogen and chlorine, are accompanied by emissions of sulfur oxides, carbon monoxide, hydrochloric acid, and halogenated organic compounds. Their emissions because of their toxicity is often limited to national limit rules, which, for example, in Germany it is established law in Regulation 17 for protection against emissions (17. BimSchV) compounds from waste incinerators.

Carbon monoxide gases (NOX) are formed during combustion of nitrogen-containing combustible materials, such as household waste or biomass, including straw or grass, waste incineration plants mainly from the associated fuel material nitrogen (N).

In technical furnaces burning solid fuels is carried out in two stages. Burn solid fuels at first the m stage, with the addition of primary air. The primary air supply is in most cases below stoichiometry. Incomplete burnout initially formed flue gases, the resulting local lack of oxygen, returnable in the burning layer, requires flow and mixing of secondary air, which starts the system still contains calories gaseous wastes. Thus there is a local very high temperatures, and ammonia (NH3) and hydrogen cyanide (HCN), initially formed from nitrogen in the fuel material during the burning of waste gases in complex reactions eventually formed NO or N2. Thermal formation of carbon dioxide (NOX- education) from nitrogen in the air, on the contrary, due to the relatively low temperature level in these waste incineration plants is relatively small.

When the so-called method SNCR (Selective Non Catalytic Reduction) ammonia (NH3or other containing N reductants, as aqueous solutions of ammonia or urea, are fed through nozzles in the oxygen-containing waste gases after burnout of waste gases in the temperature range from 850 to 1050°C for selective non-catalytic recovery of carbon monoxide in the gaseous waste. Too high temperatures lead to the formation of NO (MES shall xed nitrogen), too low temperatures increase the overshoot of NH3. In most cases, the applied aqueous solution of ammonia (NH4OH). Evaporation of this solution ammonia (NH3) is released and NO when above the level of the temperature is restored to N2

NH3can also be used as neutralizing remedies in working with neutral or slightly acidic environment scrubbers [1] SO2. If there scrubber SO2connected to the first working with the acidic environment scrubber (usually at pH values <1), in which almost quantitatively allocated HCl, SO2selectively separates connected in series in the second washing stage (scrubber SO2) with NH3at pH≤7 [2]

Educated sulfite ammonia (NH4)2SO3oxidized by oxygen contained in the gaseous waste or using the optional summed up air for oxidation of the ammonium sulfate (NH4)2SO4

Halogenated organic compounds are polychloride dibenzo-p-dioxins and dibenzofuran (PCDD/F), which are formed in the combustion process, in particular with rubbish, and cleaned gaseous waste. Education PCD/F is caused by deposits of fly ash, containing carbon and chlorine, on the surfaces of the cover or dust in the temperature range of >200°Snakeman of PCDD/F falls in the temperature range from 300 to 350°C.

Due to the toxicity of German law in regulation 17 for protection against emissions (17. BimSchV) adopted limit value of the emissions of these compounds from incineration of garbage, is equal to 0.1 ng TEQ/nm3(TEQ = equivalent toxicity). This limit value for PCDD/F at the present level of knowledge cannot be achieved exclusively by optimizing combustion conditions. In this regard, the prior art must reduce the concentration of PCDD/F in the gaseous waste products of combustion below the prescribed limit values using the included consistently flue gas. Installations for the incineration of waste are mainly from the combustion chamber, if necessary, with a casing, with at least one sequentially enabled by dust collectors and scrubbers, as well as more effective in terms of adsorption and/or catalysis operations flue gas to reduce NOXand/or PCDD/F. To reduce NOXalso often used SNGR-process.

From [3] and [4] in General it is known that the proportion of PCDD and PCDF in gaseous waste can be at burning significantly reduced only by using an excess of sulfur in relation to the totality of chlorine. This is, in particular, depends on the ratio of sulfur dioxide to the hydrochloric acid in the flue gas generated during combustion, and the rising ratio of sulfur dioxide to the hydrochloric acid begins a significant decrease in the chloride content in fly ash due to the reaction of sulfation

The chlorides of the metals show a similar behavior as the alkali. Chlorides of fly ash in sulfation transformed into sulfates. Educated poor chlorine fly ash contributes significantly noticeable reduction potential of PCDD and PCDF and thus leads to a significant decrease in the concentration of PCDD/F in gaseous waste. Poor chlorine deposits of fly ash additionally reduce the rate of corrosion of the casing.

In [5] shows the way in which SO2of the flue gas is allocated selectively in at least one scrubber and is returned into the combustion chamber in the form of SO2or sulfuric acid. Through selective allocation of SO2in the scrubber recirculation available highly concentrated SO2. Recycling leads to the enrichment of SO2and thus to decrease the relations Cl/S in the gaseous waste in the possible zones of the formation of PCDD/F. However, this method is not achieved any reduction of NOX . When the process as a residue is formed an aqueous solution of a mixture of salts of chlorides and sulphates.

On this basis, the object of the invention is to offer a device and method for the simultaneous reduction of carbon monoxide and halogenated organic compounds in installations for the incineration of garbage with at least one combustion chamber, in which the above disadvantages or limitations do not occur at all or occur in a much smaller extent.

The problem is solved using the method with the features according to claim 1 and a device with the features according to claim 5 claims. In dependent clauses reproduced preferred options for implementation.

The problem is solved using the method of reducing carbon monoxide and halogenated organic compounds in installations for the incineration of garbage with at least one combustion chamber, in which the sulfur dioxide (SO2of the flue gas is selectively deposited in at least one scrubber using ammonia or ammonium compounds, thereby forming an aqueous solution of the sulfate/ammonium sulfite, which is fully or partially returned to the combustion chamber, preferably after the afterburning zone.

The basic idea of the invention is based on the fact that, on the basis of the above SNCR method, ammonia is not introduced directly into the chamber for afterburning to mind is isenia carbon monoxide (see equation (1)), and primarily in the form of the additive is introduced into the circulation of the wash water working with a neutral or slightly acidic environment of the scrubber, which is followed by HCl-scrubber and is drawn to highlight the SO2in the formation of an aqueous solution of sulfate/sulfite ammonium (cf. equations (2) and (3)).

NH3required for SNCR method, fully or partially used for deposition of SO2in the scrubber. Formed in the scrubber when the flushing process is the solution of the sulfate/sulfite ammonium can then fully or partially be used instead of ammonia, or in addition to aqueous ammonia solution to the above SNCR-process in the afterburning zone. This leads to thermal decomposition of the sulfate/sulfite ammonia in the formation of NH3N2and SO2. The formation of SO2is almost in quantitative terms, while only a portion of the nitrogen is returned from the ammonium sulfate in the form of NH3. Educated NH3again is available to actually SNGR process. In existing plants with SNCR technique thus purified from salts of wash water (NH4)2SO4) can be replaced completely or partially before the applicable NH3. Preferably the aqueous solution of the sulfate/ammonium sulfite is added to contain islord flue gas in the temperature range between 850° C and 1050°C, mainly 900-1000°C, i.e. in the preferred SNCR-way temperature window after the afterburning zone gaseous wastes.

Not used the above solution of the sulfate/sulfite ammonium may also be in the form of ammonium sulfate (NH4)2SO4be removed from the process and separately disposed of or used.

Decomposition of sulfate and ammonium sulfite in the area of post-combustion in quantitative terms is released SO2and arrives in order to increase SO2concentration in the gaseous waste (occurs SO2circuit). Increasing the concentration of SO2may be regulated by the speed of return. In this way, the preferred way is achieved a reduction of PCDD/F in gaseous waste, while increasing the ratio of sulfur dioxide to hydrochloric acid, as once was mentioned, the increased reduction of the chloride content in fly ash is regulated by the sulfation reaction.

The decomposition of ammonium sulfate in the area of post-combustion takes place in two stages:

At more than 900°C in the afterburning chamber is increased SO2which again increases above the sulfation reaction of fly ash. While the chlorides contained in fly ash, sulphates decompose, and obrazets is hydrochloric acid, which then working in the acidic environment of the washing stage stands out from the gaseous waste.

The level of concentration of SO2can be adjusted using a rate of return of ammonium sulfate (NH4)2SO4from the second scrubber.

Thus, in the framework of the invention only substances (residues) returned from working with a neutral or slightly acidic washing stage. Using the divided sections of the scrubber becomes possible use of residual material (for example, obtaining HCl from working with acidic washing stage).

The addition of a solution of sulphate/ammonium sulfite is carried out mainly in the area of the combustion chamber preferably after the filing of the secondary gas and preferably by using multiple nozzles for one or more substances. Nozzles for one or more substances are used for spraying an aqueous solution of sulfate/sulfite ammonium and supply a homogeneous mixture with gaseous waste, and injectors for many substances, preferably using compressed air or steam.

Below the invention is illustrated on the examples of implementation using the following drawings.

Figure 1 - process flow in the process is shown schematically in the device for reduction of halogenated organic compounds is s.

Figa and b are block diagrams of known SNCR device (a) and modified on the basis of the device for simultaneous reduction of NOXand reduction of halogenated organic compounds (b).

Figure 3 - substances that are defined in the untreated gaseous waste the experience on the incineration of waste TAMARA.

The invention in combination with the installation for the incineration of garbage is, as shown in figure 1, the combustion chamber 1 from the inlet 2 of the primary gas containing oxygen, the camera 3 of the combustion chamber with the inlet 4 of the secondary gas containing oxygen, the casing 5 or other component for cooling the crude gaseous wastes 6, and includes following treatment steps for untreated gaseous waste. These treatment steps include dust collector 7 to capture the fly ash 15, such as a fabric filter or electrostatic precipitator, first working with acidic scrubber 8 (pH≤1) for selection of hydrochloric acid, and the second scrubber 9 working with neutral or slightly acidic (pH≤7) to select SO2(the removal of sulfate and ammonium sulfite 17). First working with acidic scrubber 8 is a circuit 18 with the water supply 19. After the passage of the purification steps of the purified gaseous waste 10 are discharged into the environment, for example, through the chimney.

In the second working with a neutral medium SC is ubber 9 cleaning are SO 2in the circuit scrubber 11, and it is provided by the addition of aqueous ammonia solution 12 and the separation of miscible in the scrubber solution of sulfate/sulfite ammonium.

In the second working with a neutral environment scrubber 9 cleaning are SO2in the circuit scrubber 11, and it is provided by the addition of aqueous ammonia solution 12, and the Department synthesized in the scrubber solution of sulfate/sulfite ammonium. The separated solution of the sulfate/sulfite ammonium through a connecting pipe 14 is sent to the branch pipe for gaseous waste (untreated gaseous waste) in the region of the afterburner 3 (after the burnout zone gaseous wastes). The excess part which is not the required solution of the sulfate/sulfite ammonium is removed from the process (cf. the removal of the sulfate/ammonium sulfite 17). The level of allocation is determined by the maximum desired concentration of SO2in gaseous waste and the amount of sulfate extracted from fly ash 15.

Significant is the fact that the supply of the solution of the sulfate/sulfite ammonium in the field is carried out with an excess of oxygen, which contributes to the supply of secondary gas, so that on the one hand promote the reaction shown above in the above formulas (5) and (6), i.e. to ensure effective reduction of Parn the gas, and on the other hand to stimulate the formation of sulfur oxide for reduction of halogenated organic compounds in gaseous waste.

Recirculating the solution of the sulfate/sulfite ammonium preferably at entry into the branch for gaseous waste is sprayed through one or more inlets, so that it allows to provide comparable evenly distributed over the cross section of gaseous waste reaction conditions. Preferably this is done using a flow through at least one, but better in a few acting over the entire cross section of the gaseous waste nozzles, spray one or two substances.

In the framework of the process streams are initially in the combustion chamber 1 is the burning of combustible material supplying primary gas 2, and the oxidation is not yet fully burnt part in the afterburning chamber 3 while supplying a secondary gas. The resulting crude gaseous wastes which have a temperature in the region of >900°C (i.e. sufficient for reaction (6)), are directed to the wall of the casing and give there a known amount of heat through the heat transfer to the casing 5 or inside the shell environment, and waste gases 6 are cooled to a temperature of from 200 to 300°C. the waste gases are then passed the first step of purification, p is eological 7, which gaseous waste in the framework of the example implementation of the leave at the same level of temperature in the direction of the first scrubber 8.

Dioxins and furans are formed in the branch pipe for gaseous waste preferably at temperatures above 200°C, i.e. just above the temperature level at the wall of the casing and the dust collector, but can be, as previously described, effectively reduced through formed in the area of post-combustion of sulfur oxide (reaction (6)).

In the first working with the acidic environment of the scrubber at pH-values of less than 1 hydrochloric acid using adsorption selectively allocated in the water, not accompanied by deposition of sulfur oxide. So along with the pipe 19, the water inlet, this scrubber has a pipeline for removal of hydrochloric acid 16. According to the present invention, hydrochloric acid is not required for the method of reducing nitrogen oxides and halogenated organic compounds in installations for the incineration of garbage with at least one combustion chamber and can be used for other purposes.

Named a circular process SO2leads to a gradual increase in concentrations of sulfur dioxide in the gaseous waste exactly in the above mentioned fields of education dioxin. Under ideal conditions, the molar ratio of Cl/S (hydrochloric acid to sulfur oxide) gazoobraznykh the incineration of household waste can be reduced. From 8-10 to values of <<1 (depending on the speed of recirculation).

Depicted in figure 1, the device may low-cost equipment adapted from the existing SNCR device (cf. figa), namely without the main new accession to the desired ammonia. So, install only with the help of the valves can be switched with SNCR-mode method according to paragraph 1 of the claims and Vice versa. In SNCR installation according figa supply of ammonia 12 directly into the secondary combustion chamber 2, while the circuit 11 of the second scrubber 9 is supplied with water and sodium hydroxide or calcium (intake of sodium hydroxide or calcium 23) and has a drainage sodium sulfate and sodium sulfite or calcium sulfate and sulfite potassium 24.

For retrofitting above SNCR installation in the device for additional reduction of halogenated organic compounds necessary, as shown in fig.2b, only two additional piping connections, and switching from SNCR-mode on the way to an additional reduction of halogenated organic compounds is carried out with a few shut-off/control valves. As neutralizing means instead of sodium hydroxide or calcium is now applied ammonia. The addition of ammonia is carried out via the first is Obedinenie not in the afterburning zone 3 (valve 25 closed, or fully closed), and preferably through a pipeline for ammonia 26 in the circuit 11 of the second scrubber. Supply of NH3in the step of washing SO2is regulation of pH-values. Similarly, separating the solution of the sulfate/sulfite ammonium 13 through a connecting pipe 14 to the inlet pipe 27 into the zone of combustion chamber 3.

Example experiment

Below, as an example, describes a method, device and the results of the experiments at the facility for incineration TAMARA at the research center Karlsruhe. The design matches the variant of implementation, depicted in figure 1 or 2b.

At a temperature of 1020°C. an aqueous solution of (NH4)2SO4(1 l/h, 600 g/l, in the case of gaseous waste about 1000 nm3/hour) in finely dispersed form was submitted using the nozzles for the two substances in the first gas channel (after the afterburning zone, after the supply of secondary gas). The proportion of oxygen in the area of post-combustion accounted for approximately 11% of dry volume.

Figure 3 the result is shown HCl concentration [mg/nm3] 21 and NO, and SO2accordingly, in [mg/nm3]defined in the afterburning zone and built in the form of curves in time. Blacked out badges values shown during flow through a nozzle of the above-mentioned solution of the sulfate/sulfite ammonium, while bright and the icons reference values without this filing.

Increasing the concentration of SO2and the increase in the concentration of sulphate in fly ash corresponded to the amount of sulfur in the feed solution of the sulfate/ammonium sulfite. When dosing the concentration of HCl increased immediately to 130 mg/nm3. Increasing the concentration of HCl can be explained by sulfation containing chlorides of fly ash. During the short phase of flight ash particles in the high-temperature zone of the chlorides formed a significant amount of sulfates in fly ash.

There was also a decrease in the NO concentration from 160 to 120 mg/m3. Assuming a recovery of about 50% of NH3sulphate/ammonium sulfite, when the experiment stoichiometry NH3in NO was n≈0,75. In technical installations n is set in the range from 2 to 3. The temperature in the place of filing in the presented experiment was also slightly higher than the optimum with SNCR about 980°C. Taking into account these other modes of action, with appropriate optimization, can be also achieved a significantly higher reduction of NOX. The results show that the described process in General makes possible the combined reduction of NOXand PCDD/F, as well as correspondingly increased concentration of SO2.

Using the method implemented circuit SO2 . The advantage of this variant implementation is the additional reduction of NOX. Another advantage of this process is that the concentration of SO2can be set completely independently of the concentration of HCl. The cost of the equipment, i.e. the modification of the existing SNCR installations, minor (cf. figa and b), as well as the cost of production of NH3(less than NaOH to precipitate SO2). Increasing the concentration of SO2depends on the rate of return and the concentration of the alkaline constituents of fly ash and can fundamentally be installed almost anywhere. In proportion to the increase of SO2increased consumption of NH3. For practical use in most cases for the effective reduction of PCDD/F quite a molar ratio of Cl/S (HCl/SO2about level 1. Also both circuit scrubber (scrubber 8 and 9) are formed separately, so that it becomes possible to separate the use/handling of these two flows residue.

Additive solution (NH4)2SO4in the combustion chamber before the burnout zone opposite causes only a slight reduction of NOX. This effect can only be explained by mixing caused by the flow of water through a nozzle, and the temperature decrease. Increasing the concentration of SO2it was in this case the e in accordance with the added amount of sulfate.

Figure 4 concentration of PCDD/F 28 in [ng/nm3] in the untreated gaseous waste is provided as a function of the molar ratio of Cl/S 29 (from HCl/SO2in untreated gaseous waste. Individual values were determined respectively by long-term stationary work at effective conditions of burning gaseous waste TAMARA.

Literature

1. Pstoraster, (P.Strasser), Vfuture (V.Futterer): Production experiments at the facility for removing sulfur from the flue gases of pyroelectrically in Ratchathani and the main power station in Mannheim; report on the purification of waste gases, a special notebook to maintain sanitary standards of the dust in the air (1987), notebook 10, p.63-68.

2. DE 19731062 C2.

3. R.D.Griffin, "A new theory of dioxin formation in municipal solid waste combustion", Chemosphere, Vol.15, Nos.9-12, pp.1987-1990, 1986.

4. K.Raghunathan, B.K.Gullet: Role of Sulfur in Reducing PCDD and PCDF Formation; Environ. Sci. Technol. 30 (1996) S.1827-1834.

5. DE 10338752 B4.

The list of items

1 - combustion chamber

2 - supply of primary gas containing oxygen

3 - afterburner

4 - supply of secondary gas containing oxygen

5 - casing

6 - untreated gaseous waste

7 - collector

8 - scrubber operating with the acidic environment

9 - scrubber operating with a neutral environment

10 - purified gaseous waste

11 is a circuit scrubber (second washing step)

12 - additive is of Miaka

13 - Department of sulphate/sulphite ammonium

14 - connecting pipe

15 - fly ash

16 - hydrochloric acid

17 - the removal of sulfate and ammonium sulfite

18 is a circuit scrubber (first stage leaching)

19 - water

20 - time

21 - share HCl [mg/nm3]

22 - share NO share SO2[mg/nm3]

23 supply of sodium hydroxide or calcium

24 - removal of sodium sulfate and sodium sulfite or calcium sulfate and calcium sulfite

25 - valve

26 removal of ammonia

27 - supply pipe

28 - the concentration of PCDD/F [ng/nm3TEQ]

29 - molar ratio Cl/S (dimensionless)

1. A method of reducing carbon monoxide and halogenated organic compounds in installations for the incineration of garbage with at least one combustion chamber (1, 3), and sulfur dioxide (SO2selectively precipitated from the flue gas using ammonia or ammonium compounds in at least one scrubber (9), thereby forming an aqueous solution of the sulfate/ammonium sulfite, which is fully or partially returned to the combustion chamber, comprising the following steps of the method:
a) deposition of fly ash with ash (7),
b) the release of hydrochloric acid in the first working with the acidic environment of the scrubber (8), with the addition of water,
c) the allocation of SO2in the second working with neutral or slegg the acidic environment of the scrubber (9), with the addition of water and ammonia, and this leads to the formation of ammonium sulfite and the subsequent reaction with oxygen to ammonium sulfate, dissolved in water,
d) further transfer and flow through nozzles of an aqueous solution of sulfate/sulfite ammonium in the oxygen-containing flue gas after the addition of the secondary gas, and this leads to the decomposition of the sulfate/sulfite ammonia to form ammonia and SO2and carbon monoxide in the flue gas is recovered ammonia and oxygen using selective non-catalytic recovery in nitrogen and water, and also containing chlorides fly ash in the flue gas with SO2, water and oxygen react with sulfates to form hydrochloric acid.

2. The method according to claim 1, characterized in that the aqueous solution of the sulfate/sulfite ammonium served in the oxygen-containing flue gas in the temperature range between 850 and 1050°C after the burnout zone gaseous wastes.

3. The method according to claim 1 or 2, characterized in that the additive solution of the sulfate/sulfite ammonium carried out using nozzles for one substance or nozzles for multiple substances.

4. Device for reduction of halogenated organic compounds in installations for the incineration of garbage with at least one combustion chamber, comprising:
a) dust collector (7) to capture the fly ash (15),
first working with the acidic environment scrubber (8) for allocation of hydrochloric acid with the first pipeline for removal of hydrochloric acid (16), and
c) the second working with a neutral or slightly acidic environment is connected after the first scrubber scrubber (9) with a supply of water and ammonia (12) and a second pipeline for removal of sulphate/sulphite ammonium (17), and
d) from the second pipeline branch connecting pipe (14) to the zone of combustion chamber (3) after intake of the secondary gas (4).



 

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6 dwg

FIELD: catalyst for improved hydrolysis of carbon oxysulfide (COS) and hydrocyanic acid (HCN) in gaseous mixtures.

SUBSTANCE: invention relates to application of TiO2-based composition as catalyst for COS and/or HCN in gaseous mixture releasing from apparatus for joint energy production, wherein said composition contains H2, CO, H2S and H2O in amounts of 10-40 %; 15-70 %; 200 ppm-3 % and 0.5-25 %, respectively. Moreover abovementioned composition contains at leas 1 mass.%, preferably at least 5 % at least one alkali-earth metal sulfate selected form calcium, barium. Strontium, and magnesium.

EFFECT: high conversion ratio of COS and HCN, irresponsiveness to presence of NH3, decreased production of CO2 and CH4.

8 cl, 5 ex

FIELD: complex cleaning of various industrial gaseous emissions.

SUBSTANCE: proposed method may used for complete entrapping of toxic gases, such as NOx, SO2 and CO from flue gases of fuel burning units and gaseous emissions from production units. Proposed method includes pumping of gas flow to be cleaned through reservoir filled with reaction fluid followed by settling, separation of reaction products in form of sediment and their utilization. Used as reaction fluid is trifluoroacetic acid saturated with oxygen. In the course of cleaning, composition of cleaned gases is monitored continuously. In case of penetration of contaminants, flow of gases being cleaned is directed to second reservoir filled with new portion of trifluoroacetic acid saturated with oxygen. Used trifluoroacetic acid is regenerated by saturating it with oxygen and is directed to re-cycle.

EFFECT: efficiency close to 100%.

1 ex

FIELD: chemical industry; methods of neutralization and a utilization of the aggressive chemical compounds.

SUBSTANCE: the invention is pertaining to the field of neutralization and a utilization of the aggressive chemical compounds, in particular, the saturated with the anhydrides acid-containing compounds and wastes. The neutralization is applied to the smoke mixture containing the sulfuric anhydride and chlorosulfonic acid, or the oxidizing agent of the rocket propellant based on of the nitric acid containing a dimer of the nitrogen dioxide. For neutralization use the hydrolyzed dispersible aluminosilicates based of the natural clays selected from: hydromicaceous Cambrian clay, montmorillonite clay, kaolinite clay or on the basis of their mixtures. At that the hydrolyzed dispersible aluminosilicates, which are taken at least in equal shares with an aggressive chemical compound, are prepared at the following ratio of components (in mass shares): a dry substance - 1.0-2.5, water - 1.0. The invention allows to neutralize the aggressive wastes and to produce the useful product with the sorption activity.

EFFECT: the invention ensures neutralization of the aggressive wastes and production of the useful product with the sorption activity.

3 cl, 2 ex, 6 tbl

FIELD: emission gas treatment.

SUBSTANCE: invention, in particular, relates to cleaning emission gases associated with manufacture of fired building materials to remove injurious impurities. Method according to invention consists in that reductive conditions are created within rotary furnace zone wherein temperature of emission gases is between 850 and 1400°C using burning-out of carbon-containing waste and maintaining air excess factor α = 1.05...1.1, whereas in furnace zone, emission gas temperature is below 800°C, air excess factor α is elevated to 1.2 by feeding hot air.

EFFECT: enabled conversion of nitrogen and sulfur into nitrogen and sulfur and additional removal of CO and simultaneous reclamation of coal production waste.

1 tbl

FIELD: heat-power engineering; cleaning flue gases from toxic admixtures.

SUBSTANCE: proposed method includes cooling of flue gases to temperature below dew point, condensation of water vapor, mixing of cooled flue gases with ozone-and-air mixture, oxidation and absorption of nitrogen oxides and sulfur oxides by condensate thus obtained and discharge of cleaned flue gases and condensate from zone of treatment. Flue gases and acid condensate are cleaned from carbon dioxide in perforated units of cassettes coated with layer of slaked lime [Ca(OH02] for forming calcium nitrite [Ca(NO3)], calcium carbonate (CaCO3) and calcium nitrate [Ca(NO3)]. Device proposed for realization of this method includes zone of treatment in form of box with heat-exchange and absorption-and-heat exchange sections located in this box in way of motion of flue gases. These sections are provided with air and flue gas inlet and outlet branch pipes where heat exchangers-air preheaters of 1st and 2nd stages, horizontal and vertical perforated cassettes units made from rough corrosion-resistant material coated with layer of slaked lime [Ca(OH2)], mixing chamber with perforated distributing tube and air duct with ozonizer are located.

EFFECT: enhanced ecological and economical efficiency and reliability.

3 cl, 1 dwg

The invention relates to a power system and can be used in the purification of flue gases of thermal power plants from oxides of nitrogen and oxides of sulfur

FIELD: heat-power engineering; cleaning flue gases from toxic admixtures.

SUBSTANCE: proposed method includes cooling of flue gases to temperature below dew point, condensation of water vapor, mixing of cooled flue gases with ozone-and-air mixture, oxidation and absorption of nitrogen oxides and sulfur oxides by condensate thus obtained and discharge of cleaned flue gases and condensate from zone of treatment. Flue gases and acid condensate are cleaned from carbon dioxide in perforated units of cassettes coated with layer of slaked lime [Ca(OH02] for forming calcium nitrite [Ca(NO3)], calcium carbonate (CaCO3) and calcium nitrate [Ca(NO3)]. Device proposed for realization of this method includes zone of treatment in form of box with heat-exchange and absorption-and-heat exchange sections located in this box in way of motion of flue gases. These sections are provided with air and flue gas inlet and outlet branch pipes where heat exchangers-air preheaters of 1st and 2nd stages, horizontal and vertical perforated cassettes units made from rough corrosion-resistant material coated with layer of slaked lime [Ca(OH2)], mixing chamber with perforated distributing tube and air duct with ozonizer are located.

EFFECT: enhanced ecological and economical efficiency and reliability.

3 cl, 1 dwg

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