Treatment of contaminated gas from a high pressure reactor with a fluidized bed

 

(57) Abstract:

Usage: cleaning hot gases from a high pressure reactor with a fluidized bed. In the conditions of a pressure above atmospheric hot contaminated gases pass through the separator particles with the formation on the surface of the separator cake, and immediately before or immediately after separation in the hot contaminated gases is injected reducing agent, such as reducing NOx(e.g., ammonia). Time to save the contact entered reductant increases due to low gas velocity (for example, about 1 to 50 cm/s) during the passage of gas through the cake at a pressure above atmospheric. Separation occurs in a separate pressure boiler, supported under a pressure of 2 to 100 bar, and the introduction of the reducing agent can occur at many points (corresponding to each filter element in the pressure boiler) or in one or more points just before the clean gas of a high pressure boiler (usually served on the turbine). The invention provides efficient cleaning of the gases with the removal of NOxno significant increase in emissions of N2O, CO and NH3. 2 S. p. and 23 C.p. f-crystals, 8 ill.

The invention relates to a str the ANO in the preamble of the independent claims.

For many years studied the requirements for emissions to energy industrial installations. Currently, the methods of producing energy are well studied and utilized in the production, even with improved equipment and the efficiency of trapping impurities at a low cost. In particular, for a long time has developed cost-effective ways to reduce pollution on the basis of nitrogen, oxides of nitrogen NOxand nitrogen dioxide N2O.

The nitrogen oxides formed in the combustion process in three main reactions.

The first reaction is the direct oxidation of molecular nitrogen free oxygen radicals with the formation of thermal NOx". According to current knowledge, the reaction is as

N2+ O = NO + N (1a)

N + O2= NO + O (1b)

The formation of thermal NOx" depends on the atomic concentration of free oxygen in the combustion reaction. The free oxygen atoms are formed only at high temperatures, and it is assumed that at temperatures below C (1427oC) the number of "thermal NOx" is negligible in the total emissions of NOx.

The second source is the reaction in the enriched fuel zone between education quick NOx"

CH + N2= HCN + N (2a)

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Rate of reactions (2a) and (2b) is not strongly temperature dependent, and it is expected that a significant amount of NOxformed in these reactions only under conditions of cold enrichment fuel.

As for the third source, it is flammable, containing nitrogen bound in the fuel and material released during the combustion process, forming NO, N2O and N2. Part of this nitrogen is released in the form of HCN or NH3with volatile substances, and part of the nitrogen remains in the carbonized products.

Homogeneous reaction HCN is considered the main source of nitrous oxide (N2O) formed during combustion. The aim of the reactions is:

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As NO2formed mainly due to the oxidation of nitrogen-containing compounds and the nitrogen, the oxygen concentration in the reactor affects emissions of NOxduring combustion. On the other hand, at low concentrations of oxygen can be formed monoxide carbon and other reducing agents that reduce NOxand forming N2.

In the Swedish patent 8903891 offered blowing pressure reactor with a fluidized bed of ammonia (NH3) supplied from napornogo capital recovery with additional injection of ammonia into the gas flow after the gas turbine. This document also assumes that the additional injection of ammonia on the basis of measurements of the concentrations of NOxafter the gas turbine and to catalytic reduction. However, this and other known methods of removal of nitrogen-containing pollutants in the systems pressure fluidized bed reactor still have drawbacks.

B WO 91/01793 expected to reduce emissions of NOxwhen to use combustion in the pressure reactor with a fluidized bed of the adsorbent, i.e. limestone or dolomite. Ammonia is injected into the gas stream, still containing particles of limestone. The ammonia reacts with the components of the gas stream first in the free space before the cyclone filter in the middle of the last, and then on the cake formed on the filter surface. The free space of the first reaction zone determines the time of trapping the gas mixture reduces the amount of NOx. For good mixing nitrogen gas stream and to effectively reduce the content of NOxrequire a large number of injection nozzles.

The main task of the present invention is to provide a method and device cleaning hot contaminated gases is d time spent in the hot condition without a significant increase in emissions of N2O, CO or NH3.

For achieving the above mentioned objectives of the present invention in one or more places between cecom and gas expander entered the reducing oxides of nitrogen.

According to the invention it was found that a significant number of NOxcan be converted to N2by blowing into the hot stream of gases NH3(or a similar reducing agent) at a pressure above atmospheric (typically more than 2 bar, preferably from about 2 to 100 bar). If the injection NH3is carried out at sufficiently high temperatures and the residence time of NH3at high temperatures is large enough, the side effects such as increased emissions of N2O, CO and NH3can be avoided entirely. This is especially true if the reducing agent is effectively mixed with the gas and then moves more slowly, i.e. at a rate of approximately 1-50 cm/s (preferably 1 to 10 cm/s) when passing through the particle separator.

In accordance with one aspect of the present invention, a method of cleaning hot gases from the system pressure reactor with a fluidized bed, comprising a reactor with a fluidized bed in the pressure boiler, SEPA gas after separation of particles. The method includes the following steps:

(a) compressing the gas to a pressure above atmospheric;

(b) a compressed gas in a reactor with a fluidized bed boiler and pressure so that the pressure inside pressure of the boiler is also above atmospheric;

(c) carrying out chemical reactions going on in the reactor with a fluidized bed at a pressure above atmospheric for the formation of hot contaminated gases containing gaseous impurities and particulates;

(d) while maintaining a pressure above atmospheric transport of polluted gases in the separator, causing the separation of particles from contaminated gases in the separator with clean gas and gas transportation in gas expander;

(e) carrying out steps (d) the introduction of contaminated gases reducing agent effective for at least a significant reduction in the ratio of gaseous contaminants in the contaminated gases.

Gaseous impurities in the contaminated gases include nitrogen oxides, and step (e) is normally used for introducing a reductant of NOx, preferably NH3or nitrogen-containing compounds, CO; CH4or forming nitrogen compounds. The particle separator typically includes filtering cecom, and between cecom and gas expander or only between cecom and a gas expander. Step (e) may be carried out at several points between cecom and gas expander, for example, if the separator consists of a certain number of sets of filter elements, the reducing agent can be introduced at the point of location of each set.

Usually pressure the boiler is composed of the first pressure of the boiler, and the separator is mounted within the second pressure boiler outside and separately from the first pressure boiler (second pressure boiler is under pressure above atmospheric, preferably more than 2 bar). Step (d) is also used to reduce the speed of contaminated gases between the first pressure boiler and separator, so that the rate of contaminated gas flowing through the filter device is approximately 1/10 - 1/1000 speed contaminated gases from fluidized bed. Usually the rate of contaminated gas is reduced so that the passage through the filter device, it is 1 to 50 cm/s (preferably 1 to 10 cm/s).

In several circumstances, the reducing agent is preferably administered at the time or shortly before the clean gas leaves the second pressure boiler, scolastic to 10-1000 large, than the speed during the passage of the separator) to ensure effective mixing of clean gas and reductant immediately after the introduction of the reductant.

Step (e) is preferably performed so that the amount of injected reductant was significantly minimum number necessary to ensure recovery of gaseous impurities, and leaving no excess reductant. This result of the present invention can be achieved due to pressure, low gas velocity and the selection of the points of introduction of the reducing agent.

In accordance with another aspect of the present invention proposes a method of cleaning contaminated hot gases containing NOxand particle exhaust from the burner NCPS (pressurized circulating fluidized bed). The method uses a separator for separation of particles from contaminated gases contained in the pressure boiler, the separator has a set of surfaces, each of which has a clean side and a dirty side. The method consists of the steps:

(a) flow gas igniter NCPS on the dirty side of the filter surface pressure of the boiler;

(b) separation of the solid particles from the gas thus is vitela NOxin the gas on the clean side of the filter surfaces;

(d) the optimal time to save the contact reductant NOxin Gaza to ensure optimal recovery of NOx;

(e) release of gas after performing steps (c) and (d) of the pressure of the boiler.

As noted above, the pressure in the pressure boiler normally exceeds 2 bar, preferably from about 5 to 25 bar. Step (d) is carried out while maintaining the pressure of the boiler at pressures of at least 2 bar. Step (d) further carried out by reducing the gas velocity is essentially immediately after receipt of gas pressure in the boiler, so that it is approximately 1/10 to 1/1000 of the speed of the gas before entering the pressure of the boiler; the step (d) carry out further to make the gas flow rate of about 1-50 cm/s (preferably 1-10 cm/s) when it passes through the filter surface before step (e).

According to another aspect of the present invention features a device for removing gaseous contaminants and particles from hot gases, consisting of the following elements: pressure boiler at a pressure above atmospheric, having a gas entrance and a gas exit NCPS connected to a gas inlet, and a COP has a dirty side, on which is formed a cake, and a clean side, the dirty side is connected with a gas inlet and a clean side is connected with a gas outlet. Between the gas outlet and clean sides of the filter surfaces has at least one injector for the injection of reducing agent in the pressure pot.

The device further includes a means of reducing the velocity of gas through the gas inlet so that gas has a speed of about 1-50 cm/s (preferably 1-10 cm/s) when passing through the filter surface. Means of speed reduction gas can include an inlet channel inside pressure of the boiler between the gas inlet and filter elements, for example, providing a larger volume than the path through which the gas before entering the gas inlet, so that the velocity of the gas is greatly reduced. The gas output is also attached to the turbine or other similar gas expander.

At least one injector may include an injector associated with each filter element, and/or the injector for the injection of reducing agent in the gas at or just before the release of gas from the pressure of the boiler through a gas outlet, and the gas outlet are designed in such a way that the speed of the output of the La with gas. Filter elements can include any suitable filter elements that can withstand high temperature gas (which is usually always exceeds 300oC and can reach 1200oC); currently available suitable filter elements that can be used include available ceramic finger filter elements and ceramic honeycomb filter elements.

The combination of education cake on the filter surface, high pressure and relatively low gas velocity passing through the cake, as well as effective mixing of the reductant with gaseous pollutants, increase the time spent in the contact of the reducing agent and gaseous contaminants, providing more time for the chemical reaction treatment.

The main task of the present invention is the provision of an efficient method of cleaning contaminated hot gases from a high pressure reactor with a fluidized bed, in particular, the effective removal of NOxno significant increase in emissions of N2O, CO and NH3. This and other objectives of the invention will become apparent from the detailed description of the invention and from the accompanying formula invented the item high temperature filtration system high pressure (WTVD) according to a preferred variant of the present invention.

In Fig. 2 schematically shows a variant of the pressure of the boiler to provide consistency in the treatment of hot gases according to the present invention.

In Fig. 3 through 7 show views similar to Fig. 2, for other possible pressure boilers for the implementation of the present invention.

In Fig. 8 schematically shows the pressure of the circulating reactor combustion fluidized bed, connected to a pressure boiler, for the implementation of the processing sequence of hot gases according to the present invention.

Detailed description of the drawings.

On the surface of the filter element WTVD-filtration system 1 NCPS according to a preferred variant of the present invention the filtering surface 2 (see Fig. 1) is mounted in such a way that WTVD the gas flow, the exhaust from NCPS, is forced to pass through the filter surface 2. Filtering surface 2 must withstand high temperatures of at least about 300oWith and possibly up to 1200oC. At the present time for this purpose, the preferred ceramic filter surface. Filtering in hot conditions is the study of the contaminated exhaust, and thus, it is clear that new solutions for the future.

The separation of the solid material (particulate) from the gas flow occurs when the flow of gas through the filter surface 2, so that the corresponding upstream side 4 of the filter surface 2, the gas stream contains more solids than the corresponding downward flow side 5 of the filter surface 2. Thus formed dirty (upward flow) side of the filter surface, while the downstream side is clean. Due to effect separation of solid particles on the surfaces of the filter element have a tendency to merge and form the layer 3 of the solid material, usually referred to as "cake".

In accordance with the present invention, the gas stream is brought into contact with a reducing agent of NOx essentially due to separation of solids under high pressure with the use of system 1. Due to the introduction (injection) reducing nitrogen in the gas stream prior to its passage through the filter surface 2 and KEK 3 is called the reduction of oxides of nitrogen, and the cake is an additional means to promote the reaction of nitrogen oxides with the reducing agent. Thus, there is an effective recovery of oxides of the gas flow reducing oxides of nitrogen, such as NH3, reaction accelerators - CO, CH4- or nitrogen-containing compound from the clean side 5 of the filter surface 2 in addition to or instead of injection of reducing agent prior to the filtration surface 2. It was found that under conditions of high pressure filter surface should be designed so that the velocity of the gas passing through them was small, that is, had a value of 1-50 cm/s, preferably 1-10 cm/sec. It unexpectedly leads to a successful increase in time to save the contact of the gas with the reducing agent of NOx in the immediate vicinity of the pure side 5 of the filter surface 2, and, thus, can be significantly minimized emission of compounds of nitrogen oxides in the gas stream under high pressure (i.e. at least 2 bar, preferably about 5 to 25 bar).

One of the variants of the invention shown in Fig. 2, where the gas treatment system at high pressure includes pressure boiler 21 to provide consistency of hot contaminated gases from the igniter NCPS (not shown in Fig. 2). Gas, i.e. a gas stream containing gaseous impurities and particulates after burning under davlenie 215 filtration system separates the boiler 21 into two parts: the dirty side (compressor) 24 and a clean side, that is, the camera 25, which communicates with a gas outlet 23. Filter system contains a set of 29 sets of filter elements 210, separated vertically on the dirty side 24 of the boiler 21. Depending on the design, you can make several filtering systems, preferably horizontally separated in the boiler (not shown in Fig. 2). Filter elements 210 are preferably hollow tubular elements, closed at one end and open at the other. The open end of each filter element 210 is attached to the fastener 28 which communicates with the chamber 25 of the clean side of the boiler 21, forming a supercharger for the accumulation of gas flowing through the filter surface 2 of each filter element 210. Each set 29 has a blower 27 which is connected through the fastener 28 with the chamber 25 of the clean side of the boiler 21 for the discharge of the clean gas from the boiler 21 through a gas outlet 23.

The contaminated gas is introduced into the boiler 21 through the gas inlet 22 to the dirty side 24 of the boiler 21. The boiler 21 is designed so that the velocity of the gas is greatly reduced in the boiler 21 from its value at the inlet to the inlet 22 of the circuit. The average velocity at the inlet 22 may be 10-1000 times greater than in the cat is EP, 1-10 cm/s).

After separation of the particles on the elements 210 favourable conditions for efficient recovery of NOxby injection of reductant NOx(preferably NH3) 211 points 214, 213 and 212. Each of the points 214, 213 and 212 is preferably in the immediate vicinity of the compressor 27, discharging clean gas from the 29 sets of filter elements. In point 212-214 conditions most favorable due to the expected large time saving contact and substantially cleaned from particles in the gas (clean gas). Moreover, the amount injected into each point of the reducing agent can be adjusted to minimize the "loss reducing agent" (i.e., the amount of injected reductant corresponds strictly necessary to restore the amount; excess amount of reducing agent is undesirable and, thus, prevented).

In Fig. 3 shows another variant of the pressure of the boiler according to the invention, for example, the boiler 31 for the implementation of the processing sequence of hot gases at high pressures and temperatures. Sequence numbers in Fig. 3 are similar to those in Fig. 2 by replacing the first digit to 3.

On via the inlet 32 into the first compressor 34 of the boiler. The mounting sheet 315 filtration system separates the boiler 31 into two parts: the dirty side (blower 34) and a clean side; 35mm camera (which communicates with the gas outlets 33). Filter system contains a set of 39 sets of filter elements 310, divided vertically on the dirty side 34 of the boiler. Filter elements 310 preferably the same as those described in connection with Fig. 1 and 2, for example a ceramic finger filters. The open end of each filter element 310 is directly connected to a circuit 38 for transportation of clean gas from the compressor 37 to the chamber 35 of the clean side of the boiler 31. Each set 39 has a blower 37 which is connected by circuit 38 with a 35mm camera clean side of the boiler 31.

The contaminated gas stream is introduced into the boiler 31 through the gas inlet 32 on the dirty side 34 of the boiler 31. The boiler is designed so that the velocity of the gas in the boiler 31 strongly decreases as compared with that in the circuit, the inlet gas to the gas inlet 32. The restorer of NOxpreferably NH3enter the channel 311 and the injection nozzle 312 in the chamber 35 clean side of the boiler 31. The process parameters in the variant shown in Fig. 3, such as used in the pressure reactor burning with pseudoground is stanovites into the chamber 35 clean side just before the release of gases from the boiler 31 through 33 outputs. In this case, the mounting channel 311 injection of reducing agent is relatively simple. When the purified gas flow out of the boiler, its speed is growing rapidly (at least doubled), which leads to an efficient mixing essentially immediately after the introduction of the reductant.

In Fig. 4 shows another solution according to the invention, is the same as in Fig. 3, but with a different location of injection of the reducing agent. Sequence numbers in Fig. 4 is similar to Fig. 3 by replacing the first digit by 4.

The contaminated gas stream is introduced into the boiler 41 through the gas inlet 42 on the dirty side of the boiler 41. The boiler is designed so that the velocity of the gas in the boiler 41 strongly decreases as compared with that in the circuit, the inlet gas to the gas inlet 42. The restorer of NOxpreferably NH3enter the channel 411 and the injection nozzle 412 to the gas outlet 43 in the chamber 45 clean boiler 41. The variant of Fig. 4 may have advantages if the process conditions allow injection only at the exit point of the pure gas, but can still be made for adequate recovery. If the exit gas stream from the boiler 41 its speed increases rapidly, resulting in efficient mixing of the gas and the reducing agent on the service channel 411 and the nozzle 412.

In Fig. 5 shows the boiler 51 for the implementation of the processing sequence of hot gases at high pressure. The gas stream containing impurities originating from the discharge of the burner fluidized bed, is fed into the boiler 51 through the inlet 52 to the first compressor 54 of the boiler 51. The mounting sheet 515 filtration system separates the boiler 51 into two parts: the dirty side and a clean side, the "clean" chamber 55 is connected with a gas outlet 53. Filter system contains a set of filtering elements 510, divided vertically in the bearing channel 551, allowing the flow of gas to pass from the pure side of each filter element 510 in the chamber 55 of the clean side of the boiler 51. Bearing channel 551 suspended on the fixing sheet 515. As shown, there may be multiple carrier channels 551, each of which has several filter elements 510. Also there may be several filter elements, separated horizontally around the carrier channel at the same level. Filter elements 510 are made preferably in the form of a conventional ceramic honeycomb having a set of through-channels or cells that are fully or partially formed of interconnected porous walls through which flows the filter ha is pure gas. Each channel 551 forms, thus, the supercharger to collect gas that passes through the filter surface of each filter element 510.

The flow of the contaminated gas is introduced into the boiler 51 through a gas inlet 52 on the dirty side of the boiler 51. The boiler is designed so that the velocity of the gas at the entrance to the boiler 51 is greatly reduced (for example, to 1/10-1/1000 of its former value). Through the channel 511 to the point 512 is reducing NOxpreferably NH3. Each point 512 is preferably in the lowest part of the carrier channel 551. At the point 512 terms of recovery preferred. In the bearing channel 551 reducing agent can start the recovery process, which then continues all the way to the chamber 55 of the clean side, which due to the volume of the chamber 55 is achieved by the additional increase in time to save the contact. Moreover, the number of injected reducing agent may be at each point is adjusted to minimize the "loss reducing agent". In Fig. 6 shows another variant similar to the one shown in Fig. 5, but with a different location of the point of introduction of the reductant. Sequence numbers in Fig. 6 is similar to Fig. 5 replacing the first digit of 6. Voss is th boiler 61. The variant of Fig. 6 may be preferred in cases where the process allows to introduce the reducing agent into the chamber 65 to how pure gases out of the boiler 61. When the clean gas leaves the boiler, its speed increases rapidly, resulting in efficient mixing, essentially immediately after the injection of the reducing agent.

In Fig. 7 shows the boiler 71 for the implementation of the processing sequence of hot gases from the burner NCPS under pressure above atmospheric. The gas stream containing impurities and obtained from the combustion in the fluidized bed, is injected into the boiler 71 through the outlet 72 to the first blower 74. The boiler 71 is divided into several compartments 75 and 75' off valves 771, 772 and 773, divided vertically inside the boiler 71. The selectors 771-773 with openings separated to allow installation of the substantially vertical hollow filter elements 710, passing through the holes. Hollow filter elements 710 connect this way with each other cameras 74 and 74'. Containing contamination of the gas supplied from the blower 74 in filter elements 710, then through the filtering surface of each filter element 710 in the compartments 75 and 75', while the solid particles are separated from the 5 and 75' to the path 73 of the gas exit.

The restorer of NOxpreferably NH3enter through the channels 711 points 712 each circuit 73', located in the immediate vicinity of each compartment 75, 75', collecting the gas from the filter elements 710. The amount of injected reductant at each point 712 may be such as to minimize the "loss reducing agent". In this case, achieving efficient mixing, because the gas first passes in the contours of 73 such a distance that the pattern of the flow does not have time to form before the gas is introduced into the circuit 73 gas output. The introduction of the gas leads to the effect of additional mixing, improving conditions of chemical reactions recovery.

In Fig. 8 shows the pressure of the circulation reactor with a fluidized bed 80. The system pressure of the circulation reactor with a fluidized bed, for example NCPS reactor 80, includes means 81 compression gas such as a gas compressor 81, pressure boiler 82, including the circulation reactor with a fluidized bed 83, a cyclone separator 84 and extenders gas (e.g., turbine) 85. Gas, compressed to a pressure above atmospheric (e.g., 2-100 bar), fed into the reactor 83 fluidized bed inside the pressure kennym layer. Circulating fluidized bed of solids is maintained in the reactor 80 fluidized bed by known methods. Hot gas formed as a result of chemical reactions in a circulating fluidized bed and carrying Deputy solid material enters the cyclone separator 84 for separating solid particles. Current gas, essentially free of large particles, but still containing gaseous impurities and small particles, transported by the circuit 86 in the pressure boiler 87 for the implementation of the processing sequence of hot gas at a pressure above atmospheric.

Pressure boiler 87 may be of any design shown in Fig. 2-7. In accordance with the present invention for gas is set to the processing sequence, which includes the transportation of gas from the reactor 83 fluidized bed on a path 86 to the device 88 is separated from the hot gas particles in the pressure boiler 87, Department of part of the particles from the hot gas to produce clean gas and transportation of clean gas to the device 85 of the gas expansion. When performing the processing sequence for the recovery of gaseous pollutants, such as NH3, blown the present invention in the separation of solid particles in the gas stream is brought into contact with a reducing agent of NOx. By reductant injection of nitrogen into the gas stream before the stream passes through the device 88 separation, improves the recovery of oxides of nitrogen. Thus, it provides efficient recovery of oxides of nitrogen at a pressure above atmospheric and at high temperatures, for example about 300 - 1200oC. Usually in the reactor with a fluidized bed can be the surface, generating steam; volatile wall construction or tubular batteries, for example in a furnace for combustion, controlling the reaction. During normal operation, the pressure is not reduced deliberately, and the temperature of the gas between the first and second pressure boilers 82, 87 is not reduced intentionally. Typically, the pressure between boilers 82 and 87 is not reduced intentionally.

In some cases, preferably the reductant injection of nitrogen oxides in the gas stream from the clean side of the separation device 88, such as circuit 90, instead of (or in addition) injection at position 89 to the separation device 88. It was found that at a pressure above atmospheric filtering surface can be performed so that the speed of passing through the bottom of the gas is small (for example, 1-50 cm/s, preferably 1-10 cm/s). It suddenly causes the bones to the clean side of the filter surface, and, thus, it is possible to minimize the emission of compounds that contain nitrogen oxides in the gas stream, with increasing time the optimum temperature for the injection of ammonia to a certain extent reduced. Therefore, the residence time provided by the injection of reducing agent to clean the surface of the device separation is very favorable.

In some cases, in addition to the injection of reducing agent in the points 89 and 90, can be successful using channels 91 and/or 92 for further injection into the reactor 83 and/or a cyclone separator 84. In this case, the injection of reducing agent can be controlled by selecting the number and location of injection in accordance with, for example, the load from the pressure reactor with a fluidized bed 80, so that for all operating modes of the system 80 provides optimum time to save contact and recovery NOx.

The surface of the filter elements in accordance with all variants of Fig. 2-8 essentially comparable with the surface of the filter element, is described in detail in connection with Fig. 1.

The system 80 may also contain other conventional components such as security, pulse reverse washing system sstic 94) and other similar.

The invention is described in connection with the considered this the most preferred and feasible option, but it should be understood that the invention is not limited to the disclosed solution, but instead refers to various modifications and equivalent solutions, including the scope and objectives of the attached claims.

1. Cleaning method hot contaminated gases from the system pressure reactor with a fluidized bed, comprising a reactor with a fluidized bed within the first pressure boiler, a separator for separating particulate from the contaminated gas with a filter element, and having a filtering surface with a dirty side, on which is formed a cake, and clean side and a gas expander for expansion of the gas after separation of particles, comprising the steps of: (a) compressing the gas to a pressure above atmospheric; (b) a compressed gas in a reactor with a fluidized bed boiler and pressure when the pressure inside the pressure above atmospheric boiler; (c) carrying out chemical reactions going on in the reactor with a fluidized bed at a pressure above atmospheric for the formation of hot contaminated gases containing gaseous impurities, including nitrogen oxides, and mA is arator for separating particles from a contaminated gas in the separator with clean gas, and transportation of gas in a gas expander; (e) in process step (d) introduction to contaminated gases reductant, wherein step (e) is carried out in one or more points between cecom and a gas expander.

2. The method according to p. 1, wherein step (e) undertake to ensure the injection of reducing oxides of nitrogen to the clean side of the filter element.

3. The method according to p. 1, wherein step (e) provide for the introduction of NH3, compounds containing nitrogen, CO, CH4or acetobromo compounds as the reducing agent.

4. The method according to p. 1, wherein step (e) being carried out between the fluidized bed and cecom.

5. The method according to p. 1, characterized in that the separator with a filter element is placed within the second pressure boiler, outside and separate from the first pressure of the boiler, and the step (d) is used to reduce the speed of contaminated gases between the first pressure boiler and separator including a filter element for the speed of contaminated gases when passing through the filter device is approximately 1/1 - 1/1000 speed contaminated gases from fluidized bed and the second pressure boiler, outside and separately from the first pressure of the boiler, and the step (d) is used to reduce the speed of contaminated gases between the first pressure boiler and separator for the speed of contaminated gases when passing through the filter element is about 1 to 50 cm/sec.

7. The method according to p. 1, characterized in that the separator with a filter element is placed within the second pressure boiler, outside and separate from the first pressure of the boiler, and the step (d) is used to reduce the speed of contaminated gases between the first pressure boiler and separator for the speed of contaminated gases when passing through the filter element is about 1 to 10 cm/sec.

8. The method according to p. 1, wherein step (e) being carried out only between cecom and a gas expander.

9. The method according to p. 1, characterized in that the separator with a filter element is placed within the second pressure boiler, outside and separate from the first pressure of the boiler, and the step (d) is carried out by passing the clean gas from the second pressure of the boiler to the gas expander located in a position that is external to the second pressure of the boiler, and the velocity of gas quickly, at least doubled when or just before as clean gas exits the second pressure of the boiler to ensure effective mixing of clean gas and reducing oxides of nitrogen immediately after the introduction of the reductant.

10. The method according to p. 1, characterized in that in stage (e) maintain the number of reductant of NOx essentially at the level needed to restore the amount of oxides of nitrogen.

11. The method according to p. 1, wherein step (e) is carried out in several stages.

12. The method according to p. 1, characterized in that the separator include multiple sets of filter elements connected to a common clean gas channel, and the step (e) is used for the injection of reducing nitrogen oxides in the clean gas channel at different points for each set of filtering elements.

13. The method according to p. 1, characterized in that the separator include a variety of tubular filter elements, each of which has a dirty side and a clean side, and the step (e) is used for the injection of reducing oxides of nitrogen to the clean side of each filter element are different for each filter element point.

14. The method according to p. 1, characterized in that in the process of implementing all sicasica fact, for cleaning hot contaminated gases containing NOxand particles in it, the exhaust from the burner pressure circulating fluidized bed using a separator for separating particulate from the contaminated gases contained within the second pressure boiler, with many of the filtering surfaces, each of which has a clean side and dirty side, and the method includes the following stages: - flow of gas from the igniter pressure circulating fluidized bed on the dirty side of the filter surfaces in the second pressure boiler separation from gas to solid particles on the filter surface with the formation of the dirty sides of the filter surfaces cake - supply reductant NOxin gas, located on the clean side of the filter surfaces, ensuring optimal time to save the contact reductant NOxin Gaza to optimize recovery NOxand the release of gas from the second pressure boiler after performing steps (c) and (d).

16. The method according to p. 15, characterized in that the velocity of the gas essentially immediately after the filing of the second pressure boiler is reduced to about 1/10 - 1/1000 speed gas before entering P1 - 50 cm/sec in passing through the filter surface before it cleared.

18. The method according to p. 15, characterized in that the gas is sent at a rate of approximately 1 to 10 cm/s when passing through the filter surface before it cleared.

19. The device for removal from the hot gases gaseous pollutants, including nitrogen oxides and particles containing pressure boiler operating at a pressure above atmospheric and having a gas inlet and a gas outlet, a pressurized circulating fluidized bed connected with a gas inlet, and a multitude of filter elements mounted inside the pressure pot between input and output, each filter element has a filter surface with a dirty side, on which is formed a cake, and a clean side and the dirty side is connected to the input, and the blank side is connected with a gas outlet, characterized in that the device includes, at least one injector for the injection of reducing oxides of nitrogen pressure in the boiler between the clean side of the filter surfaces and gas output.

20. The device according to p. 19, characterized in that it includes means for reducing the speed of the supplied gas in the gas inlet to provide Pro p. 20, characterized in that the means for reducing the speed includes the inlet channel and the blower inside pressure of the boiler between the gas inlet and filter elements.

22. The device according to p. 19, characterized in that it includes a means of expanding gas, coupled with a gas exit.

23. The device according to p. 19, wherein the at least one injector includes an injector of each of the filter elements.

24. The device according to p. 19, wherein the at least one injector includes an injector for the injection of reducing nitrogen oxides in the gas at or just before the gas exits the pressure of the boiler through the gas outlet, the gas outlet is arranged to provide a gas velocity at release from the gas outlet, at least, rapid doubling to ensure good mixing of the reductant with the gas.

25. The device according to p. 19, characterized in that the filter elements include multiple sets of ceramic finger filter elements or multiple ceramic honeycomb filter elements.

 

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The invention relates to the field of purification of various gaseous emissions from industrial production and recycling of industrial waste and can be used in chemical, energy and other industries

The invention relates to a cleaning gas containing nitrogen oxides, toxic impurities, particularly to the purification of the fumes from thermal plants, prior to their emission into the atmosphere

The invention relates to methods of gas purification from impurities of oxides of sulfur and nitrogen and can be used for cleaning flue gases obtained by combustion of solid fuels, as well as in the chemical industry, in particular in the manufacture of sulfuric acid nitrous or combined contact and nitrous method
The invention relates to industrial ecology and can be used for the purification of gaseous emissions of nitrogen oxides
The invention relates to the field of power engineering, in particular to the burning of coal, oil, and other fuels in the furnaces of the boilers of thermal power plants, heating plants, etc

The invention relates to a method of trapping gases obespredmechivanie and emissions from the door of the coke-pitch furnaces

The invention relates to the field of applied chemistry, environmental protection, in particular to a method for cleaning exhaust gases of atmospheric air, water, soil and other objects of the environment from toxic substances, in particular of different oxides, carcinogenic nitrosamines, polycyclic aromatic hydrocarbons (PAHs)

The invention relates to a method of cleaning exhaust gas containing hydrogen chloride and sulphur dioxide, and ustroystvo for its implementation

The invention relates to a method of removing sulfur dioxide from waste gases, comprising contacting containing sulfur dioxide off-gas with an aqueous solution containing sulfuric acid, hydrogen bromide and bromine, with the formation of sulfuric acid and hydrogen bromide, catalytic vapor-phase oxidation of the obtained hydrogen bromide into bromine and subsequent recycling of bromine to the first stage of the process

The invention relates to a method for treatment of solid residues after combustion, to a device for treatment of solid residues after combustion installation combustion, in particular to the waste incinerator grate and adjacent to it, filled with liquid and having an input shaft and the discharge ejector system to remove toxins, which remains after combustion are transported to the outside through the up gravity discharge chute

FIELD: production of aluminum in cells with self-fired anodes, possibly processes for cleaning anode gases.

SUBSTANCE: method comprises steps of accumulating anode gases, preliminarily combusting them together with air in burner devices mounted in cells; supplying gas-air mixture after preliminary combustion of anode gases along gas duct to stage of dust and gas trapping and blowing out to atmosphere. Before supplying gas-air mixture from burner devices to stage of dust and gas trapping, it is fed to process for oxidizing roasting; heated up to temperature 800-1100°C and then it is cooled until 230-290°C and heat is used for production needs.

EFFECT: lowered content of carbon, resin and CO in exhaust gases.

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