NOx and CO integrated removal device for coke oven flue gas

Abstract

The utility model provides a coke oven flue gas NOx and CO integrated removal device, which relates to the technical field of flue gas purification and comprises a flue, an ammonia gas inlet pipe, a flue gas heater, a flue gas heat exchanger, a temperature detection component, an integrated reactor, an SCR (selective catalytic reduction) catalyst, a CO catalyst and a discharge component. According to the design, heat is released in the process of removing CO through CO catalytic oxidation, so that the temperature of flue gas is increased, and the temperature of flue gas which is not denitrated before entering the integrated reactor can be increased through the flue gas heat exchanger, so that the removal process of NOx and CO in the coke oven flue gas is better, and the energy consumption of the flue gas heater is effectively reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to the flue gas purification technical field, specifically, relate to a coke oven flue gas NO x And CO integrated removal device. BACKGROUND

[0002] With the completion of the treatment of the three traditional atmospheric pollution sources (SO2, NO x And dust), the influence of CO on the environment and human life has entered the public's field of vision, and the current relevant policies for CO treatment are mainly concentrated on sintering flue gas, but the CO concentration in coke oven flue gas is also high, the CO concentration in coke oven flue gas burning coke oven gas is about 2000-3000mg / Nm³, the CO concentration in coke oven flue gas burning blast furnace gas is about 5000-6000mg / Nm³, and the current relevant policies have required that the emission concentration of CO in coke oven flue gas is not higher than 2500mgN / m³, so the treatment of CO in coke oven flue gas has also been increasingly concerned.

[0003] At present, after the desulfurization of coke oven flue gas, the NO x And CO in it need to be purified, and in the process of coke oven flue gas denitration, long-time heating needs to be maintained to make the denitration temperature reach about 230°, and the purification and removal process of CO in coke oven flue gas is an exothermic reaction (specifically using CO catalyst), and at present, the exothermic heat of CO cannot be effectively utilized to heat NO x , and further, the removal process of NO x And CO in coke oven flue gas needs to be optimized. INVENTION CONTENTS

[0004] The utility model aims at solving the problems in the above background technology, and further puts forward a coke oven flue gas NO x And CO integrated removal device.

[0005] The technical scheme adopted by the utility model to solve the technical problems is:

[0006] A coke oven flue gas NO x And CO integrated removal device, which comprises a flue, an ammonia gas inlet pipe and a flue gas heater, and further comprises a flue gas heat exchanger, a temperature detection assembly, an integrated reactor, an SCR catalyst, a CO catalyst and a discharge assembly,

[0007] The temperature rising side inlet end of the flue gas heat exchanger is communicated with the flue.

[0008] The flue gas heater is communicated with the temperature rising side outlet end of the flue gas heat exchanger, and the flue gas heater is electrically connected with the temperature detection assembly.

[0009] The inlet end of the integrated reactor is communicated with the flue gas heater, and the ammonia gas inlet pipe is communicated with the gas path pipe between the flue gas heater and the integrated reactor; the outlet end of the integrated reactor is communicated with the flue gas heat exchanger and the cooling side inlet end;

[0010] The SCR catalyst and the CO catalyst are arranged in the integrated reactor;

[0011] The emission assembly is communicated with the flue gas heat exchanger and the cooling side outlet end.

[0012] Further, the temperature detection assembly comprises a temperature sensor and a PLC control panel; the temperature sensor and the flue gas heater are electrically connected with the PLC control panel so as to maintain the temperature sensor in the set temperature range by adjusting the heating power of the flue gas heater.

[0013] Further, the emission assembly comprises an induced draft fan and a coke oven chimney; the flue gas heat exchanger and the cooling side outlet end are communicated with the induced draft fan air inlet pipe; the induced draft fan air outlet pipe is communicated with the coke oven chimney.

[0014] Further, the SCR catalyst is above the CO catalyst.

[0015] Further, the reaction temperature ranges of the SCR catalyst and the CO catalyst are consistent; and the SCR catalyst and the CO catalyst are selected as medium-low temperature catalysts.

[0016] Further, the flue gas heat exchanger adopts one of a rotary heat exchanger, a tubular heat exchanger and a plate heat exchanger.

[0017] Further, the integrated reactor is arranged as two so that when the catalyst in one integrated reactor is replaced, the other integrated reactor can meet the low load operation of the coke oven.

[0018] Compared with the prior art, the beneficial effects of the utility model are:

[0019] 1. The design can effectively remove NOx and CO in the flue gas of the coke oven, so that the emission concentration of NOx in the flue gas of the coke oven is lower than 100 mg / Nm3, and the concentration of CO is lower than 2500 mg / Nm3. x x 3 3

[0020] 2. The design removes NOx first and then removes CO, thereby effectively protecting the CO catalyst from the influence of ammonia gas.

[0021] 3. The design releases heat in the CO catalytic oxidation process, so that the temperature of the flue gas is increased, and then the temperature of the flue gas entering the integrated reactor can be increased through the flue gas heat exchanger, thereby effectively reducing the emission concentration of NOx in the flue gas of the coke oven. x ​​​​The removal process of the CO is more optimal, and the energy consumption of the flue gas heater is effectively reduced;

[0022] 4、The flue gas purified by the integrated reactor is lowered in temperature by the flue gas heat exchanger, and then the induced draft fan air volume can be reduced, so that the energy consumption of the induced draft fan is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is a whole structure schematic view of the utility model;

[0024] Reference signs:

[0025] 1, flue; 2, ammonia gas inlet pipe; 3, flue gas heater; 4, flue gas heat exchanger; 5, integrated reactor; 6, SCR catalyst; 7, CO catalyst; 8, temperature sensor; 9, PLC control panel; 10, induced draft fan; 11, coke oven chimney. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model. The utility model will be further described in combination with the drawings and embodiments:

[0027] As shown in the drawings, Figure 1 A coke oven flue gas NO x And CO integrated removal device, including flue 1, ammonia gas inlet pipe 2, flue gas heater 3, flue gas heat exchanger 4, integrated reactor 5, SCR catalyst 6, CO catalyst 7, temperature sensor 8, PLC control panel 9, induced draft fan 10 and coke oven chimney 11,

[0028] The temperature rising side inlet end of flue gas heat exchanger 4 is communicated with flue 1 (specifically, flue gas heat exchanger 4 adopts one of rotary heat exchanger, tubular heat exchanger or plate heat exchanger);

[0029] Flue gas heater 3 is communicated with the temperature rising side outlet end of flue gas heat exchanger 4;

[0030] Temperature sensor 8 is arranged at the inlet of integrated reactor 5, and temperature sensor 8 and flue gas heater 3 are electrically connected with PLC control panel 9 to maintain temperature sensor 8 in the set temperature range by adjusting the heating power of flue gas heater 3;

[0031] The inlet end of the integrated reactor 5 is communicated with the flue gas heater 3, and the ammonia gas inlet pipe 2 is communicated with the gas path pipeline between the flue gas heater 3 and the integrated reactor 5, and the outlet end of the integrated reactor 5 is communicated with the cooling side inlet end of the flue gas heat exchanger 4;

[0032] The SCR catalyst 6 and the CO catalyst 7 are both arranged in the integrated reactor 5;

[0033] The cooling side outlet end of the flue gas heat exchanger 4 is communicated with the air inlet pipe of the induced draft fan 10, and the air outlet pipe of the induced draft fan 10 is communicated with the coke oven chimney 11.

[0034] In order to avoid the situation that the CO catalyst 7 is arranged in advance and the ammonia gas is attached to the surface of the CO catalyst 7, thereby affecting the CO removal effect, as shown in the further refinement of the scheme, the SCR catalyst 6 is arranged above the CO catalyst 7. Figure 1

[0035] In the further optimization of the above embodiment scheme, the reaction temperature ranges of the SCR catalyst 6 and the CO catalyst 7 are consistent, and the SCR catalyst 6 and the CO catalyst 7 are selected as medium-low temperature catalysts, so that the energy consumption and the investment cost can be saved.

[0036] In the further optimization of the embodiment scheme of the utility model, as shown in the further optimization of the above embodiment scheme, the integrated reactor 5 is arranged as two, so that when the catalyst in one integrated reactor 5 is replaced, the other integrated reactor 5 can meet the low load operation of the coke oven, realizes the on-line maintenance, and meets the characteristics that the coke oven cannot be stopped. Figure 1

[0037] In the further optimization of the above embodiment scheme, as shown in the further optimization of the above embodiment scheme, the integrated reactor 5 is arranged in multiple layers, the SCR catalyst 6 is arranged in two layers, the standby layer (SCR catalyst 6) is arranged in one layer, and the CO catalyst 7 is arranged in one layer. Figure 1

[0038] The working process of the utility model is as follows:

[0039] ​​​Firstly, the denitration reaction temperature is set to 230 DEG C, then the flue gas after denitration is subjected to catalytic oxidation of CO by CO catalyst 7, so that the CO concentration in the flue gas is reduced from 6000 mg / Nm3 to below 2500 mg / Nm3, at the same time, heat is released to raise the flue gas temperature from 230 DEG C to 250 DEG C, the flue gas after removal of CO at 250 DEG C is exchanged with the coke oven flue gas after desulfurization at 170 DEG C by flue gas exchanger 4, then the flue gas temperature after removal of CO is reduced to 190 DEG C and is discharged through coke oven chimney 11 after induced draft fan 10, the flue gas after desulfurization is heated from 170 DEG C to 230 DEG C, which matches the reaction temperature of SCR and CO catalyst 7, during normal operation, flue gas heater 3 can be stopped, only the heat released by CO catalytic oxidation reaction can meet the requirement of flue gas temperature rise before denitration, flue gas heater 3 is only operated in the initial stage of equipment operation, and the flue gas temperature is raised to 230 DEG C after denitration, only the heat released by CO catalytic oxidation reaction can realize the system heat balance.

[0040] The basic principle, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principle of the present application, and various changes and improvements can be made to the present application without departing from the spirit and scope of the present application, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A type of coke oven flue gas NO x The integrated CO removal device includes a flue (1), an ammonia inlet pipe (2), and a flue gas heater (3), characterized in that... It also includes a flue gas heat exchanger (4), a temperature detection assembly, an integrated reactor (5), an SCR catalyst (6), a CO catalyst (7), and emission components. The inlet end of the flue gas heat exchanger (4) on the heating side is connected to the flue (1). The flue gas heater (3) is connected to the heating side outlet end of the flue gas heat exchanger (4), and the flue gas heater (3) is electrically connected to the temperature detection component; The inlet end of the integrated reactor (5) is connected to the flue gas heater (3), and the ammonia gas inlet pipe (2) is connected to the gas pipeline between the flue gas heater (3) and the integrated reactor (5). The outlet end of the integrated reactor (5) is connected to the cooling side inlet end of the flue gas heat exchanger (4). Both the SCR catalyst (6) and the CO catalyst (7) are placed inside the integrated reactor (5); The emission component is connected to the cooling side outlet of the flue gas heat exchanger (4).

2. The coke oven flue gas NO according to claim 1 x The integrated CO removal device is characterized in that, The temperature detection component includes a temperature sensor (8) and a PLC control panel (9). The temperature sensor (8) and the flue gas heater (3) are both electrically connected to the PLC control panel (9) so that the temperature sensor (8) can be maintained within the set temperature range by adjusting the heating power of the flue gas heater (3).

3. The coke oven flue gas NO according to claim 1 x The integrated CO removal device is characterized in that, The emission components include an induced draft fan (10) and a coke oven chimney (11). The cooling side outlet of the flue gas heat exchanger (4) is connected to the inlet pipe of the induced draft fan (10), and the outlet pipe of the induced draft fan (10) is connected to the coke oven chimney (11).

4. The coke oven flue gas NO according to claim 1 x The integrated CO removal device is characterized in that, The SCR catalyst (6) is positioned above the CO catalyst (7).

5. A coke oven flue gas NO according to claim 4 x The integrated CO removal device is characterized in that, The SCR catalyst (6) and CO catalyst (7) have the same reaction temperature range, and the SCR catalyst (6) and CO catalyst (7) are selected as medium and low temperature catalysts.

6. A coke oven flue gas NO according to claim 1 x The integrated CO removal device is characterized in that, The flue gas heat exchanger (4) is one of a rotary heat exchanger, a tubular heat exchanger or a plate heat exchanger.

7. A coke oven flue gas NO according to claim 1 x The integrated CO removal device is characterized in that, The integrated reactor (5) is configured in two so that when the catalyst is replaced in one integrated reactor (5), the other integrated reactor (5) can meet the low-load operation of the coke oven.

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