Method of neutralization and utilization of the aggressive chemical compounds
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
The invention relates to the field of disposal and recycling of aggressive chemical compounds, in particular saturated anhydrides acid compounds and waste,
More specifically the invention is a method of disposal and recycling of stored reserves smoke a mixture of C-4, which is extremely saturated solution of sulfuric anhydride in chlorosulfonic acid with a mixture of sulfuric acid and which is highly aggressive liquid, corrosive metals and calling in contact with human skin heavy, slow-healing wounds.
The method can also be used for the disposal and recycling of oxidizer rocket fuel (melange), which is an extremely saturated solution of the dimer of nitrogen dioxide in nitric acid, as well as for the disposal of other aggressive chemical compounds.
The destruction of aggressive chemicals and waste is an extremely important and complex task, requiring the development of unique technologies. While the developed technology must meet stringent requirements:
- complete and guaranteed security:
- the absence of the original components or decomposition products with the environment
- high degree of reliability at all stages of process the of process,
- low level of economic costs.
There are many ways to kill aggressive chemical compounds, such as flooding or disposal at great depth, destruction by explosion, combustion, and chemical neutralization. Many of them have exhausted their potential and do not comply with environmental legislation.
Widely known used by leading industrial countries, the destruction of aggressive chemicals and waste, based on direct combustion of substances in the furnace with subsequent purification of exhaust gases, is protected by US patents 5711917 And from 18.09.06, US 5574203 And from 27.10.94, DE 3028193 C2 from 25.07.08, DE 4428418 C2 from 11.08.94 and others.
Famous Russian developments destruction of chemical wastes by methods of high-temperature processing, in particular, are protected by patents RU 2005519 from 19.05.92, EN 2022590 from 20.05.91, EN 2064308 from 27.04.92, 2093229 from 19.03.96, 2156631 from 25.10.95.
The disadvantages of these technologies can be attributed to the emergence of a significant ecological impact on the environment. In addition, these methods involve the use of high temperatures, it is necessary to use specially equipped furnaces with refractory and chemically resistant lining, equipped with special devices for flue gas cleaning. The use of known methods is possible only in case is ach ensure the destruction of chemical compounds in the pyrolysis process.
Known also more environmentally friendly methods of disposal of chemicals and waste - burning without oxygen. For example, the method consisting in providing a contact chemical compounds with highly reactive carbon mixture, which is used expanded graphite, and the destruction of chemical bonds by pyrolysis under the action of currents of ultra-high frequency (UHF) (Patent RU 2154803 C1, F 24 D 5/04, 06 D 7/00, 09.02.99).
However, the use as a highly reactive carbon mixture of expanded graphite considerably increases the cost of this process, in conjunction with the necessity of using a special oven with microwave generator makes extensive use of the known method. In addition, the use of this method for the destruction of aggressive acidic chemical waste, such as smoke a mixture of S-4 or the oxidizer propellant, is unacceptable due to the fact that there is no separation and recycling of the components of these compounds.
There are also other chemical methods of disposal and recycling of aggressive chemicals and waste.
For example, in the method according to Z. DE 19629423, AND 62 D 3/00, 1999, proposed for the disposal of acids and acid waste using fly ash of different furnace installations with the free lime content bol is e 10%. The amount of ash should ensure that the concentration of residual free lime than 3%, which is due pozzolanicity reaction is able to be cured products of neutralization. These materials can be granulated and used as agricultural fertilizer.
There is also known a method of disposal and/or regeneration of waste acids (HCl, H3SO4, HNO3N3RHO4), which consists in the reaction of an acid solution with a molar concentration of [H+] 4-8 with a metal oxide is ZnO or MgO, resulting in the formation of oxisol, water and heat. Received oxisol smachiwausa with filler (crushed stones, granite, quartz, corundum, talc, sand, asbestos, metal powder, etc.). The mixture was molded, dried at T=20°received inert blocks used in construction (U.S. Pat. EPO 1028088, 01 17/90, Z. 99102522.2 from 10.02.99).
However, the use of the above methods for the disposal and recycling of flue mixture of C-4 or oxidizer propellant is unacceptable, as the above chemical compounds are not homogeneous acidic mixture, and the mixture of gaseous products (acid anhydrides or dimer of nitrogen dioxide and acids located in the limiting concentration of the state in which the dissociation of acids and their interaction with the oxide is mi metals impossible. The use of water to reduce the concentration of acid is also impossible due to the explosive uncontrollable exothermic reaction interaction of these substances with water, accompanied by the release of a large amount of thermal energy.
The closest present invention is a method of disposal of aggressive chemical compounds, including neutralization of chemical compounds by carrying out hydrolysis for the destruction of the past and create a flow of wastewater, biological treatment of the wastewater stream and the catalytic oxidation of exhaust gases, converting the components into valuable chemicals by catalytic purification (U.S. Pat. EN 2203116 C2, 2203116, A 62 D 3/00, 18.09.1998).
However, this method is unacceptable for disposal and recycling of flue mixture of C-4 and oxidizer propellant in connection with the impossibility of separation of acid and dissolved therein gaseous products and the direct hydrolysis of these chemical compounds free water due to its explosive nature.
Smoke a mixture of C-4 contains a solution of sulfuric anhydride in chlorosulfonic acid with a mixture of sulfuric acid (SO3- (37-40)%, HClSO2- (54-60)%, H2SO4-(3-7)%) and represents strongly fuming liquid. When contact C-4 with the air going on the t selection sulfuric anhydride, which by interaction with air moisture to form droplets of sulfuric acid that is accompanied by release of heat energy. This thermal energy contributes to the formation of sulfuric vapors and resulting collapse of chlorosulfonic acid hydrochloric and sulphurous acids, forming a white fog (smoke). The interaction of C-4 with water is accompanied unmanaged release of exothermic energy, i.e. the translation contained in the radicals of the acids to a certain concentration with the use of free water is impossible. It follows that environmentally friendly division of the initial complex of sulfuric, hydrochloric and chlorosulfonic acid without gas formation and excretion into the environment of toxic substances is only possible with the combination of the specified complex environment that does not contain free water.
The oxidizer rocket fuel (melange) is a solution of the dimer of nitrogen dioxide in nitric acid with a mixture of iodine (N2O4- 27%, HNO3- 72%, J - 0.5 percent). Its interaction with water vapor contained in the atmosphere, causing rapid selection of brown gas (NO2)by reaction with water produces a large quantity of heat, the reaction is uncontrollable explosive nature. That is, the separation and disposal of this chemical compound with ispolzovaniem water is also impossible.
The purpose of creation of the present invention is to develop a method of disposal and recycling of aggressive chemical compounds, in particular smoke a mixture of C-4 and oxidizer propellant.
The technical result from use of the present invention is in the separation and destruction of these aggressive chemical compounds during hydrolysis in the presence of bound water, as well as in simplifying the process of neutralization and reduction of its cost and complexity.
This technical result is achieved in that in the method of disposal and recycling of aggressive chemicals and wastes, including disposal of components of chemical compounds by conducting hydrolysis degradation, according to the proposal hydrolytic degradation combined with the separation of the components of corrosive chemical compounds and is conducted in the presence of bound water is present in the colloid-dispersed and/or Sol-gel mass, which use hydrolyzed dispersed silicates on the basis of natural clays and/or mixtures thereof, taken from a number hydrosluide Cambrian, montmorillonite, kaolinite clay occurs. This technical result is also achieved by the fact that hydrolyzed silicates prepared in the following ratio,wt. parts: dry matter 1,0-2,5, water - 1,0, and hydrolyzed silicates and aggressive chemical compound take, at least, in equal shares. This technical result is also achieved by the fact that hydrolyzed silicates can be prepared from a mixture of hydrologists Cambrian and montmorillonite clay at a ratio of 1:1, or a mixture hydrologists Cambrian, montmorillonite and kaolinites clay in the ratio of 1:1:1 and can optionally contain 2-3 wt.% lime and 3-5 wt.% magnesium oxide, and the resulting end product of hydrolytic degradation of aggressive chemical compounds can be used as a sorbent.
The applicant has not identified the sources of information that contain information about technical solutions, identical to the present invention, which allows to make a conclusion about its compliance with the criterion of "novelty".
Hydrolyzed silicates on the basis of natural clays are colloidal disperse the Sol-gel system, characterized by extreme hydration. Water in this system is loosely coupled condition with the Sol-gel and colloidal phases and can be used for slow hydrolysis aggressive chemical compounds, saturated anhydrides or their derivatives, such as smoke a mixture of C-4 or oxidant RA is to maintain fuel.
Contained in the smoke of a mixture of C-4 sulphur dioxide (SO3when interacting with colloidal disperse the Sol-gel phases aluminosilicates, being more hydrophilic compound than the last, absorbs weakly bound water and forms a concentrated sulfuric acid (H2SO4. The latter, being very hydrophilic compound, the absorption of weakly bound water reduces its concentration up to 60-70%. The resulting acid, reacting with silicates, carries out their acid hydrolysis, resulting from the crystal lattices of clay minerals extracted alkali and alkaline earth metals, as well as amphoteric Al2About3and Fe2About3. The oxides of these metals when interacting with sulfuric acid to form the corresponding sulfate, and the system gets released water molecules, which contributes to the further hydrolysis of interacting components. Thus, it achieves the separation of gaseous sulfur trioxide and acid and its complete conversion into sulfuric acid, which is consumed by acid hydrolysis of silicates and formation of the corresponding salt of the compounds (oxyconti). Since the reaction concentration reduction and formation of acid is exothermic in nature, the eye-catching at the same time those who lo improves the intensity of the acidic hydrolysis of silicates, which is endothermic. That is the rational combination of two opposite processes - exothermic and endothermic, which prevents the possibility of intensive evaporation of the acid. Similarly flows and the process of acid hydrolysis of silicates chlorosulfonic acid (HClSO2), which decomposes to hydrochloric (HCl) and sulfur (HSO2) acid. The formation of chlorides and sulfides of the elements extracted from the crystal lattice silicates (chlorides and sulfides of sodium, potassium, magnesium, calcium, aluminum and iron).
When interacting hydrolyzed silicates with oxidizer propellant dissolved in nitric acid dimer dioxide nitrogen (N2O4), interacting with weakly bound water, is converted to nitric (HNO3) and nitrogen (HNO2) acid, which simultaneously with the source of nitric acid and the resulting iodomethane (HJ) acid involved in the acid hydrolysis of silicates. Formed during acid hydrolysis, as in the above case, interact with oxides of elements extracted from the crystal lattice silicates. This also is a combination of exothermic and endothermic processes. Heating of the reaction mass does not exceed 60-80°S, th is prevents the secretion of acid vapors and other gaseous products.
Obtained as a result of these processes is the end product of acid hydrolysis of dispersed silicates contains colloidal disperse the Sol-gel phase silica, alumina, iron hydroxides, and solid particles of clay minerals with an imbalanced crystalline lattice. This system is an extremely non-equilibrium mineral mix, which according to the principle of Le Chatelier's principle capable of regenerated with decreasing concentration gidroliznaya agents. The system tends to an equilibrium state that ensures its high sorption capacity. The obtained acidic sorbent can be used for cleaning contaminated alkaline and neutral wastewater, and when introducing additives lime or fly ash can be converted in an alkaline sorbent.
Used to obtain hydrolyzed silicates amount of water determines, in its turn, the amount of water bound to the Sol-gel and colloidal disperse phases hydrolyzed silicates, which is involved in the separation and transformation of the components of corrosive chemical compounds. These values are derived and verified experimentally. The increase in the number of dry matter of silicates, i.e. reducing the number of bound water in the aluminosilicates below the stated limits is a, increases the viscosity of the mixture, making it difficult not only for its preparation (mixing), but further use, since it does not provide sufficient contact of the reactants and conversion of sulfuric anhydride or dimer of nitrogen dioxide into the corresponding acid is not complete. At the same time increasing the amount of water used for hydrolysis of silicates, i.e. the increase in the number of bound water in the latter, due to their interaction with aggressive chemical compound leads to a sharp intensification of the process of separation and conversion components of chemical compounds in acid, the release of a large amount of heat and unmanaged during the reaction, as in this case, hydrolyzed silicates contain many weakly bound water, close to free. Reducing the number of hydrolyzed silicates to aggressive chemical compound with the implementation of the method also leads to a reduction in the number of bound water contained in a total reaction mass and, in particular, to aggressive chemical compound that leads to incomplete separation and conversion components specified connection. The implementation of the method, with an equal proportion of hydrolyzed silicates and aggressive chemical compounds in charge of the AET necessary and sufficient content of bound water in the reaction mass and prevents off-gassing when mixing by providing sufficient contact of the reactants.
As for the source of the material used to obtain hydrolyzed silicates, the first choice from a number hydrosluide Cambrian, montmorillonite or kaolinite clay occurs, dictated by local conditions - the presence of deposits of certain types of clays, their composition. The most easily hydrolyzed montmorillonite clay, and hydrologist Cambrian occupy an intermediate position between them and kaolinite clays.
Introduction hydrolyzed silicates additives, lime and magnesium oxide increases the output of the colloid-dispersed and Sol-gel phases and increases the mobility of the hydrolyzed mixture, which improves the subsequent interaction of the reagents and helps to speed up the separation and transformation of the components of corrosive chemical compounds.
These circumstances, according to the applicant, indicate compliance of the claimed technical solution the criterion of "inventive step".
The possibility of implementing the invention is confirmed by experiments and illustrated by the following examples.
This example describes the process of disposal and recycling of flue-mixture C-4 using hydrolyzed silicates (silica-alumina paste - up)made from hydroslide is the Cambrian clay at a ratio T/W of 1.5:1,0, where T is the dry matter, W - water. The choice of the source material due to the presence of significant local fields hydrologists Cambrian clay, which significantly reduces costs for implementing method.
For the preparation of silica-alumina paste in laboratory stirrer made of powder hydrologist Cambrian clay content of clay particles (d=0,002 mm) 23% and with constant stirring introduced the mixing water in a predetermined ratio. That is, to 600 g of aluminosilicate powder was added to 400 g of water. Mixing is conducted to achieve a homogeneous mixture. Introduced in clay water as a result of interaction with the clay particles formed in the above-mentioned mixture of colloidal-disperse the Sol-gel phase, which ensured its complete absorption, i.e. the water has turned into a bound state.
For disposal and recycling of flue mixture of C-4 was used pressurized mixer, equipped with a screw feeder for feeding alumina paste, pipe, coupled with the pump for supplying recyclable chemical compounds, and vent pipe with water bolt. The last in case of a minor short-gassing during the interaction of the smoke mixture of C-4 with air moisture in its supply prevents uncontrolled escape of gas from the volume mixer.
After the filing in the mixer aluminosilicate pasta with continuous stirring pump filed smoke a mixture of C-4 in number, equal to the weight of aluminosilicate paste - 1000, the number of bound water in relation to the mass of C-4 was 0.4, which is sufficient to convert part of the smoke mixture-4 sulfuric anhydride. This is due to the fact that the content of sulfur dioxide in the flue of a mixture of C-4 is not more than 40%, and for the conversion of one molecule of sulfuric anhydride need one water molecule, the molecular weight of which is more than four times less (SO3+H2O=N2SO4). The excess of bound water was used to reduce the concentration of the formed sulfuric acid and acid included in the smoke mixture of C-4, which contributed to the intensification of their dissociation and subsequent acid hydrolysis of the silicates. Stirring of the mixture was performed for 5 minutes, after which it reached a homogeneous state. In the process of combining smoke a mixture of C-4 and aluminosilicate paste selection gaseous products did not occur. When interacting smoke a mixture of C-4 with gidrolizovannykh aluminosilicates (AP) in the working volume of the mixer was increased temperature up to 64°C. the results of laboratory samples of the reaction medium after interaction with a smoke mixture of C-4 has changed in the sour side for a few units. Initial pH value of 6.9, after interaction With-4 with alumina paste and degradation of whom is onenew smoke mixture pH 0.4. Discharging the reaction mixture into the drive was made after it cools. After holding the mixture in the drive for 24 hours the pH of the hydrolyzed mass increased by 1.0 to 1.5 units, which was a consequence of buffering mineral system aluminosilicates.
The final product is an acidic paste, which is highly effective aluminosilicate sorbent, which can be used, for example, for the purification of alkaline and near-neutral industrial effluents. If necessary, by adding lime, soda or alkali in the amount of 10-30% of the total weight of the paste, this sorbent can be converted into alkaline and used as such for the purification of acidic waste.
For the destruction of a rocket fuel oxidizer (ORT) was used aluminosilicate paste hydrologists Cambrian clay, obtained as described above.
After submitting aluminosilicate paste in the working volume of the mixer was supplied to the oxidizer propellant in the amount of 1:1 relative to the alumina paste. The amount of bound water in the specified aluminosilicate pasta enough for conversion is included in the oxidizer propellant dimer of nitrogen dioxide to nitric and nitrous acid. The mass of the dimer of nitrogen dioxide makes up about a quarter of samassi oxidant, to convert one molecule of nitrogen dioxide in acid needed one water molecule, the molecular weight of which is approximately five times less than its molecular weight (N2O4↔2NO3+H2O=HNO3+HNO2).
With the introduction of oxidizer propellant in the working volume of the mixer has been little selection of brown gas (NO2), which ceased with the beginning of the interaction with alumina paste in the mixing process. The duration of mixing was 7 minutes, after which the mixture has become homogeneous consistency. The temperature in the working volume of the mixer was raised to 65°, separation of the gaseous products were observed, the pH of the final product of 0.5.
To implement the method used available materials and standard equipment, which allows to make a conclusion on the compliance of the claimed invention, the criterion of "industrial applicability".
The results of the experiments hydrolytic degradation of smoke mixed With 4 for different weight ratios of silicates and water in the hydrolyzed silica-alumina paste determining the amount of bound water in the reaction mixture, and different weight ratios of silica-alumina paste and smoke a mixture of C-4 are presented in tables 1-3. In tables 4-6 present the results of similar experiments on g is droleskey destruction of rocket fuel oxidizer.
The ratio AP:p-4=1,0:1,0
|N p/p||The ratio T/W in the AP||The amount of bound water in the AP per unit weight S-4||The temperature of the mixture interaction, °||The PH of the mixture||Interaction with AP|
|1||2,3:1,0||0,303||42-51||<0,1||Vapor acid under stirring|
|2||1.7:1,0||0,370||51-50||0,1-0,2||A small selection of acid vapors in the initial mixing|
|3||1.5:1,0||0,400||60-66||0,2-0,5||Selection of acid vapors is not observed|
The ratio AP:4=1.5:1,0
|N p/p||The ratio T/W in the AP||The amount of bound water in the AP per unit weight S-4||The temperature of the mixture interaction, °||The PH of the resulting mixture||Interaction of C-4 with AP|
|1||2,3:1,0||0,456||64-72||0,7-1,7||Pair acids are not highlighted|
|5||1,0:1,0||0,750||90-100||2,7-2,9||Violent reaction and boiling water|
The ratio AP:p-4=1,0:1,5
|N p/p||The ratio T/W in the AP||The amount of bound water in the AP per unit weight S-4||The temperature of the mixture interaction, °||the pH of the mixture||2,3:1,0||0,202||25-30||<0,1||Intense vapor acid under stirring|
|1,0:1,0||of 0.333||49-55||0,1-0,2||Visible vapor under stirring|
|* excessive amounts of C-4 in combination with a low content of bound water (weight thick) lead to increased contact With-4 with air and intense vapor|
The ratio AP:OPT=1.0:1.0
|N p/p||The ratio T/W in aluminosilicate pasta||The amount of bound water in the AP on a single the TSU weight ORT||The temperature of the interacting mixture, °||The PH of the mixture||Interaction OPT with AP|
|1||2,3:1,0||0,303||35-40||<0,1||Selection of brown fumes NO2when mixing|
|2||1,7:1,0||0,370||40-48||0,1-0,2||A small selection of brown vapours in the initial mixing|
|3||1,5:1,0||0,400||47-56||0,2-0,5||Vapor is not observed|
|4||1.2:1,0||0,450||55 to 63||0,5-1,0||″-″|
The ratio AP:ORT=1,5:1,0
|N p/p||The ratio T/W in aluminosilicate pasta||The amount of bound water in the AP per unit weight ORT||The temperature of the interacting mixture, °||the pH of the mixture||Interaction of ORT with AP|
|1||2,3:1,0||0,456||61-72||0,7-1,1||Vapor is not observed|
|5||1,0:1,0||0,750||89-95||2,7-2,9||Intensive during reaction|
Sootnoshenie AP: ORT=1,0:1,5
|N p/p||The ratio T/W in aluminosilicate pasta||The amount of bound water in the AP per unit weight ORT||The temperature of the interacting mixture, °||the pH of the mixture||Interaction OPT with AP|
|1||2,3:1,0||0,202||20-23||<0,1||Intensive promotional is of vapors NO 2|
|4||1,2:1,0||0,300||35-40||0,4-0,5||Visible vapor NO2|
1. The method of disposal and recycling of aggressive chemicals and wastes by mixing with a binder, characterized in that the neutralization is subjected to the smoke mixture, representing a solution of sulfuric anhydride in chlorosulfonic acid mixed with sulfuric acid or the oxidizer propellant, representing a solution of the dimer of nitrogen dioxide in nitric acid, mixed with iodine, and use the silicates in the form of a paste, prepared on the basis of natural clays from a number hydrosluide Cambrian, montmorillonite, Kalinicheva in the following ratio of components, ensuring the transfer of water in the bound state, the weight. including:
moreover, silica-alumina paste is used in a quantity at least equal to the number of delaborated connection.
2. The method of disposal and recycling according to claim 1, characterized in that the alumina paste further comprises the following components, wt.% (on dry matter):
3. The method of disposal and recycling according to claim 1, characterized in that the resulting neutralization of the final product is used as a sorbent.
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.
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
FIELD: methods of purification of flue gases.
SUBSTANCE: the invention is pertaining to the method of purification of flue gases and may be used to decrease the outbursts of nitrogen oxide with the help of the method of the high-temperature selective non-catalytic reduction. The method provides for feeding of the previously prepared steam-gaseous reduction mixture into the gas flue of the flue gas burning aggregate with the temperature of the flow of the purification gases of 700-1200°C. At that the steam-gaseous reduction admixture is prepared in the connected to the gas flue high-speed reactor during 0.5-5 seconds by introduction of a water solution of carbamide with a superheated steam at the pressure of 3-10 atm. Concentration of the water solution of carbamide makes 20-40 mass %. The time of the contact of the water solution of carbamide with the superheated steam predominantly makes 0,5-2 seconds. The pressure in the reactor predominantly makes 3-6 atm. The temperature of the superheated steam makes 200-400°C. The invention ensures simplification of the production process of purification of the effluent gases from nitrogen oxides, to increase the level of purification of such a gas in the broad range of the temperatures of the purified combustion products, and also to decrease significantly the share of the secondary contaminant - ammonia, in the purified gases.
EFFECT: the invention ensures simplification of the production process of the effluent gases purification from nitrogen oxides, to increase the level of purification of the gases in the broad range of the temperatures of the purified combustion products, to decrease significantly the share of the secondary contaminant - ammonia in the purified gases.
5 cl, 2 ex, 1 dwg, 2 tbl
FIELD: physical or chemical processes and apparatus.
SUBSTANCE: method comprises flowing air through the chemical absorber of nitrogen acids that is composed of chemically absorbing base that absorbs nitrogen dioxide and sorbent-oxidizer that oxidizes nitrogen mono-acid up to nitrogen dioxide. The chemical absorber is made of n pairs of layers of chemically absorbing base and sorbent-oxidizer. Upon flowing throughout n pairs of the layers, the initial concentration of the nitrogen dioxide drops by a factor of 3n, where n is the total number of pairs of the layers.
EFFECT: reduced cost and enhanced efficiency.
2 cl, 1 tbl
FIELD: method of desulfurization of waste gases; power engineering, chemical industry, ferrous and non-ferrous metallurgy.
SUBSTANCE: proposed method includes heterogeneous-catalytic oxidation of sulfur dioxide contained in flue gases and absorption of sulfuric anhydride formed during this procedure by water. Used as catalyst are ferrospinels prepared on base of manganese-zinc powder in form of thin plates which are constantly crushed directly in zone of oxidation of SO2 and SO3 in aqueous medium continuously generating freshly formed catalytically active surfaces. Process is performed under normal conditions: room temperature and atmospheric pressure.
EFFECT: enhanced efficiency.