CN210663964U

CN210663964U - Coke oven flue gas denitration and waste heat recovery device

Info

Publication number: CN210663964U
Application number: CN201921302615.4U
Authority: CN
Inventors: 李毛; 张建国; 王新义; 吕有厂; 曹德彧; 周云辉; 王军; 李二军; 畅宾平; 高建伟; 王育红; 李龙; 周跃辉; 谷小虎
Original assignee: Pingdingshan Jingbao Coking Co Ltd Of China Pingmei Shenma Group; China Pingmei Shenma Energy and Chemical Group Co Ltd
Current assignee: Henan Pingmei Shenma Jingbao Chemical Technology Co Ltd; China Pingmei Shenma Energy and Chemical Group Co Ltd
Priority date: 2019-08-13
Filing date: 2019-08-13
Publication date: 2020-06-02
Anticipated expiration: 2029-08-13

Abstract

The utility model provides a coke oven flue gas denitration and waste heat recovery device, belong to coke oven flue gas denitration technical field, including the denitration reactor, entry flue and steam pocket, the entry flue is the S type, by last horizontal part, vertical portion constitution of lower horizontal part and connection lower horizontal part, the left end import of lower horizontal part is the flue gas import, the right-hand member of going up the horizontal part links to each other with the top import of denitration reactor, from last denitration catalyst layer that has set gradually under to in the cavity of denitration reactor, evaporation heat exchanger and preheating heat exchanger, the below of denitration reactor is equipped with clean flue gas export, evaporation heat exchanger ' S import and export link to each other through pipeline and steam pocket respectively, preheating evaporator ' S import even has the soft water pipeline, preheating evaporator ' S export passes through hot water pipeline and steam pocket and links to each other.

Description

Coke oven flue gas denitration and waste heat recovery device

Technical Field

The utility model belongs to coke oven flue gas denitration field, concretely relates to coke oven flue gas denitration and waste heat recovery device.

Background

For flue gas denitration, a reduction method using ammonia as a raw material is mature and reliable, and the reaction principle is as follows:

NO+0.25O₂+NH₃=N₂+1.5H₂o, ammonia reduces NOx to nitrogen and water, eliminating pollution. 1mol of NO consumes 1mol of ammonia,reduced to 1 ton NO₂0.37 ton of ammonia was consumed. The project was designed to a maximum that would consume 130kg of ammonia per hour. The methods are classified into non-catalytic selective reduction (SNCR) methods without a catalyst and Selective Catalytic Reduction (SCR) methods with a catalyst. The SNCR method requires that the reaction temperature is 850 ℃ and 950 ℃ and the denitration efficiency is 50-70%. It is clear that coke oven flue gas is not suitable for SNCR.

The residual heat brought by the coke oven flue gas accounts for nearly one third of the residual heat utilization of the whole coking system. In order to save a smoke outlet induced draft fan and possible problems thereof in the past, smoke is directly discharged from an underground flue communicated chimney, and for a combustion chamber of a coke oven, the smoke directly forms creeping force to provide air for the coke oven.

In recent years, with the improvement of energy conservation, especially environmental protection standard, the utilization of the waste heat of the flue gas of the coke oven becomes an important direction. However, the existing waste heat utilization device is easy to have the problem of operation stability due to the particularity of the coke oven flue gas.

The coke oven flue gas contains a small amount of tar, soot and SO in addition to the components mentioned above₃. Recently, combined with a denitration device, waste heat utilization is generally arranged at the rear part of a denitration reactor, and flue gas also contains NH₃At the same time as SO thereof₃The content is also multiplied. This phenomenon can easily cause scaling of the heat exchange tubes of the boiler until the heat exchange surfaces are finally blocked.

Therefore, the utilization of the waste heat of the flue gas of the coke oven has the technical problem of reducing or eliminating the above influence compared with the conventional utilization of the waste heat. At present, few publications on this point are reported.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a coke oven flue gas denitration and waste heat recovery device.

Based on the above-mentioned purpose, the utility model discloses take following technical scheme:

the utility model provides a coke oven flue gas denitration and waste heat recovery device, including the reactor of taking off a round pin, entry flue and steam pocket, the entry flue is the S type, by last horizontal part, horizontal part and the vertical portion of connecting lower horizontal part constitute down, the left end import of lower horizontal part is the flue gas import, the right-hand member of going up the horizontal part links to each other with the top import of denitration reactor, from last denitration catalyst layer that has set gradually down in the cavity of denitration reactor, evaporation heat exchanger and preheating heat exchanger, the below of denitration reactor is equipped with clean flue gas export, evaporation heat exchanger ' S import and export link to each other through pipeline and steam pocket respectively, preheating evaporator ' S import even has the soft water pipeline, preheating evaporator ' S export links to each other through hot water pipeline and steam pocket.

Further, an ammonia gas mixing component is arranged below the vertical part of the inlet flue and connected with a raw material ammonia pipeline outside the inlet flue, and a hole plate is arranged in a cavity of the denitration reactor above the denitration catalyst layer.

Further, the denitration catalyst layer is divided into 2 to 4 layers, the filling height of each layer of catalyst is 1.0 to 1.8 m, and the distance between adjacent layers is 1.0 to 1.6 m.

Further, the denitration catalyst is a honeycomb catalyst, honeycomb holes are circular holes, square holes or hexagonal holes, and the size of the honeycomb holes is 3-6 mm.

Furthermore, the evaporation heat exchanger and the preheating heat exchanger are both tube type heat exchangers with finned tubes, the fins are made of aluminum sheets, the distance between the fins is 3-6 mm, and the height of the fins is 25-45 mm.

Further, the thickness of the perforated plate is 6-20 mm, the perforated plate is a square hole, a round hole or a strip-shaped hole, and the flow area of the perforated plate is one fourth to one third of the cross-sectional area of the denitration reactor.

Furthermore, the steam drum is connected with the inlet of the evaporation heat exchanger through a downpipe line, the outlet of the evaporation heat exchanger is connected with the steam drum through an uppipe line, the inlet of the preheating heat exchanger is provided with a soft water pipeline, and the preheating heat exchanger is connected with the steam drum through a hot water pipeline.

Further, the ammonia gas branch pipe is included, and a jet pipe is vertically arranged on the ammonia gas branch pipe. And a steam output pipe is arranged on the steam pocket.

The utility model discloses be equipped with the ammonia mixed component on the entry flue, make the ammonia and more even that the entry flue gas mixes, set up the orifice plate in the packing layer top, make the entering packing layer that the gas mixture can be even, heat in the flue gas after the denitration is through evaporating heat exchanger and preheating heat exchanger and the aqueous vapor heat transfer that is close the saturation, makes the aqueous vapor be vapor, and steam and separation of water produce 0.6MPa saturated steam in the steam pocket, through the external output of outer pipe network.

Drawings

Fig. 1 is a schematic structural diagram of the present invention;

fig. 2 is a schematic view of the ammonia mixing component of fig. 1.

Detailed Description

The following detailed description is provided for the technical solution of the present invention with reference to the specific embodiments and the accompanying drawings, but the technical solution of the present invention is not limited to the specific embodiments and the accompanying drawings.

A coke oven flue gas denitration and waste heat recovery device is shown in figure 1 and comprises a denitration reactor 100, an inlet flue 200 and a steam drum 300, wherein the inlet flue 200 is S-shaped and consists of an upper horizontal part, a lower horizontal part and a vertical part connected with the upper horizontal part and the lower horizontal part, the left end inlet of the lower horizontal part is a flue gas inlet, the right end of the upper horizontal part is connected with the top inlet of the denitration reactor 100, a denitration catalyst layer 40, an evaporation heat exchanger 50 and a preheating heat exchanger 60 are sequentially arranged in a cavity of the denitration reactor 100 from top to bottom, a clean flue gas outlet 70 is arranged below the denitration reactor 100, the inlet and the outlet of the evaporation heat exchanger 50 are respectively connected with the steam drum 300 through pipelines, the inlet of the preheating evaporator 60 is connected with a soft water pipeline 2, and the outlet of the preheating evaporator 60 is connected with the steam drum 300 through a hot water pipeline.

Further, an ammonia gas mixing member 20 is arranged below the vertical part of the inlet flue 200, the ammonia gas mixing member 20 is connected with the raw material ammonia pipeline 1 outside the inlet flue 200, and a pore plate 30 is arranged in the cavity of the denitration reactor 100 above the denitration catalyst layer 40.

Further, the denitration catalyst layer 40 is divided into 3 layers, the filling height of each layer of denitration catalyst is 1.0-1.8 m, and the distance between adjacent layers is 1.0-1.6 m.

Further, the denitration catalyst is a honeycomb catalyst, honeycomb holes are circular holes, square holes or hexagonal holes, and the size of the honeycomb holes is 3-6 mm. The honeycomb catalyst contains MoO₃V of₂O₅/TiO₂Catalyst and MoO₃The mass of (A) is 2.5-5% of the total amount of the catalyst, and V is₂O₅The mass accounts for 1.5 to 3.0 percent of the total mass of the catalyst.

Further, the evaporation heat exchanger 50 and the preheating heat exchanger 60 are both tube type heat exchangers with finned tubes, the fins are made of aluminum sheets, the distance between the fins is 3-6 mm, and the height of the fins is 25-45 mm.

Further, the thickness of the orifice plate 30 is 6 to 20 mm, and the opening is a square hole, a circular hole or a strip-shaped hole, and the flow area of the opening is one fourth to one third of the cross-sectional area of the denitration reactor 100.

Further, the drum 300 is connected to an inlet of the evaporating heat exchanger 50 through a downer line 4, and an outlet of the evaporating heat exchanger 50 is connected to the drum 300 through an uper line 5.

Further, as shown in fig. 2, the ammonia mixing component 20 includes an ammonia branch pipe 12, the ammonia branch pipe 12 is vertically provided with jet pipes 11, and the jet pipes 11 are arranged in a matrix.

And a steam output pipe 6 is arranged on the steam pocket 300.

The working process of the utility model is as follows: flue gas with the temperature of 230-280 ℃ subjected to desulfurization enters an inlet flue 200 through a flue gas inlet 10, at the moment, ammonia enters an ammonia mixing component 20 through a raw material ammonia pipeline 1, the flue gas is contacted and mixed with the flue gas in a cavity of a vertical part of the inlet flue 200 to obtain mixed gas, the mixed gas uniformly enters a denitration reactor 100 through a pore plate 30, nitrogen oxides in the flue gas react with the ammonia under the action of a denitration catalyst to achieve the aim of denitration, the denitrated flue gas is still a high-temperature gas mixture, soft water enters a preheating heat exchanger 60 and then primarily exchanges heat with the flue gas, the heated soft water enters a steam pocket 300, water in the steam pocket 300 exchanges heat with hot flue gas through an evaporation heat exchanger 50, the water is converted into steam, the steam and the water are separated in the steam pocket 300 to generate 0.6MPa saturated steam, and the saturated steam is output outwards through a steam output.

Claims

1. The utility model provides a coke oven flue gas denitration and waste heat recovery device, including the reactor of taking off a round pin, entry flue and steam pocket, a serial communication port, the entry flue is the S type, by last horizontal part, the vertical portion of horizontal part and connection lower horizontal part is constituteed down, the left end import of lower horizontal part is the flue gas import, the right-hand member of going up the horizontal part links to each other with the top import of denitration reactor, from last denitration catalyst layer that has set gradually down in the cavity of denitration reactor, evaporation heat exchanger and preheating heat exchanger, the below of denitration reactor is equipped with clean flue gas export, evaporation heat exchanger ' S import and export link to each other through pipeline and steam pocket respectively, preheating evaporator ' S import even has soft water pipeline, preheating evaporator ' S export links to each other through hot water pipeline and steam pocket.

2. The coke oven flue gas denitration and waste heat recovery device of claim 1, wherein an ammonia gas mixing member is arranged below the vertical part of the inlet flue, the ammonia gas mixing member is connected with a raw material ammonia pipeline outside the inlet flue, and a hole plate is arranged in the cavity of the denitration reactor above the denitration catalyst layer.

3. The coke oven flue gas denitration and waste heat recovery device of claim 1, wherein the denitration catalyst layer is divided into 2 to 4 layers, the filling height of each layer of catalyst is 1.0 to 1.8 m, and the distance between adjacent layers is 1.0 to 1.6 m.

4. The coke oven flue gas denitration and waste heat recovery device as claimed in any one of claims 1 to 3, wherein the denitration catalyst is a honeycomb catalyst, the honeycomb holes are circular holes, square holes or hexagonal holes, and the size of the honeycomb holes is 3 to 6 mm.

5. The coke oven flue gas denitration and waste heat recovery device of claim 1, wherein the evaporation heat exchanger and the preheating heat exchanger are both tube type heat exchangers with finned tubes, the fins are made of aluminum sheets, the spacing of the fins is 3-6 mm, and the height of the fins is 25-45 mm.

6. The coke oven flue gas denitration and waste heat recovery device of claim 2, wherein the thickness of the perforated plate is 6 to 20 mm, the perforated plate is a square hole, a round hole or a strip-shaped hole, and the flow area of the perforated plate is one fourth to one third of the cross-sectional area of the denitration reactor.

7. The coke oven flue gas denitration and waste heat recovery device as claimed in claim 1, wherein the steam drum is connected with the inlet of the evaporation heat exchanger through a downpipe line, and the outlet of the evaporation heat exchanger is connected with the steam drum through an uppipe line.

8. The coke oven flue gas denitration and waste heat recovery device of claim 2, wherein the ammonia gas mixing component comprises an ammonia gas branch pipe, and a jet pipe is vertically arranged on the ammonia gas branch pipe.

9. The coke oven flue gas denitration and waste heat recovery device of claim 1, wherein a steam output pipe is arranged on the steam drum.