CN213984618U - Steam-water system for recycling full waste heat of primary flue gas of converter - Google Patents

Abstract

The utility model relates to a technical field of industry waste heat recovery utilizes, concretely relates to complete waste heat recovery's of converter primary flue gas steam-water system. The system comprises a movable smoke hood, a hood skirt, a vaporization cooling flue, a membrane wall combined type waste heat recovery device with independently replaceable heat pipes, a high-pressure steam drum and a low-pressure steam drum. The membrane water-cooled wall combined type waste heat recovery device with the independently replaceable heat pipes is adopted to effectively cool the high-temperature flue gas, so that the waste heat of the primary flue gas of the converter is recovered to the maximum extent; by means of the vaporization cooling flue, the membrane water wall combined type waste heat recovery device with the heat pipe capable of being replaced independently, the multistage combined flue gas waste heat recovery device with the reinforced fin heat exchange pipe structure, the explosion-venting overflow flue gas temperature adjusting/fire arrester and the torch waste heat recovery device with the reinforced fin heat exchange pipe structure, the total flue gas waste heat under the working states of converter oxygen blowing smelting and non-oxygen blowing smelting is effectively recovered.

Description

Steam-water system for recycling full waste heat of primary flue gas of converter

Technical Field

The utility model relates to a technical field of industry waste heat recovery utilizes, concretely relates to complete waste heat recovery's of converter primary flue gas steam-water system.

Background

Energy conservation and emission reduction are subjects of current social development, and the recycling of waste heat resources is one of effective ways for saving energy and reducing pollution. The converter steelmaking, which is the main steelmaking process of steel enterprises, generates gas containing carbon monoxide as a main component, a small amount of carbon dioxide and other trace components in the blowing process, and also carries a large amount of iron oxide, metal iron particles and other fine particle solid dust, thus seriously polluting the atmosphere and the workshop environment. Therefore, the technical level of the converter dust removal system is improved, and the recovery and utilization of converter gas and the recovery of flue gas waste heat have great significance for saving energy and reducing consumption in steelmaking, effectively controlling and reducing the emission of steelmaking atmospheric pollutants and reducing environmental pollution.

The temperature of the converter flue gas outlet is about 1400-1600 ℃, the dust concentration is 70-200 g/m3, after leaving the converter mouth, the converter flue gas is cooled to 800-1000 ℃ by adopting a vaporization cooling flue or a water cooling flue, and then the converter flue gas enters a flue gas dust removal system to reduce the dust concentration so as to meet the national emission standard and the requirements of gas users. At present, the domestic converter primary flue gas dust removal process mainly comprises the traditional OG method, the new OG method, the semi-dry method, the dry method (LT method) and other dust removal processes.

At present, no matter which process system is adopted for primary flue gas purification of the converter, the common characteristics of the process systems are that the cooling of high-temperature flue gas is realized, the cooling of the flue gas is realized by absorbing latent heat of vaporization through evaporation of water, and a large amount of steam is consumed for dry (LT) dedusting because of the requirements of the system. Cooling the flue gas by consuming water is an efficient cooling method, but a very energy consuming method. Because the high-temperature flue gas from the evaporative cooling flue is high-grade heat energy, the heat energy carried by the high-temperature flue gas is not recovered, and a large amount of other energy sources are consumed to cool the high-temperature flue gas, a large amount of energy is wasted, and the high-temperature flue gas is also a main reason for generating smoke and rain. For example, under the general design condition, the temperature of the flue gas discharged from the vaporization flue is 800-1000 ℃, and if the temperature of the flue gas is simply reduced to 500 ℃, steam generated by ton steel can reach 20kg, and huge benefit can be generated.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a converter primary flue gas full waste heat recovery's soda system.

The steam-water system for primary flue gas full waste heat recovery of the utility model comprises a movable smoke hood, a hood skirt, a vaporization cooling flue, a membrane water wall combined waste heat recovery device with independently replaceable heat pipes, a high-pressure steam drum and a low-pressure steam drum, wherein,

the high-pressure steam pocket, the downcomer, the heat pipe evaporator at the upper part of the membrane water-cooled wall combined type waste heat recovery device with the independently replaceable heat pipe, the membrane water-cooled wall evaporator at the upper part of the membrane water-cooled wall combined type waste heat recovery device with the independently replaceable heat pipe and the riser form a high-pressure evaporator system;

water in the high-pressure steam pocket enters an evaporator of the evaporative cooling flue through a descending pipe, absorbs heat of flue gas to form a steam-water mixture, enters the high-pressure steam pocket through an ascending pipe, is separated by a steam-water separator in the high-pressure steam pocket, and then steam is conveyed into a heat accumulator from the high-pressure steam pocket;

the heat pipe evaporator in the middle of the membrane water wall combined type waste heat recovery device with the independently replaceable heat pipes forms a coal economizer, water from the water dividing header is heated to 170 ℃, and then the water is sent to the high-pressure steam pocket;

the low-pressure steam pocket, the downcomer, the lower heat pipe evaporator of the membrane water wall combined type waste heat recovery device with the independently replaceable heat pipe, the lower membrane water wall evaporator of the membrane water wall combined type waste heat recovery device with the independently replaceable heat pipe, the riser and the like form a low-pressure evaporator system;

water in the low-pressure steam pocket enters each evaporator through a downcomer to absorb heat of flue gas to form a steam-water mixture, and low-pressure saturated steam generated by entering the low-pressure steam pocket through an ascending pipe is conveyed to a deaerator and used for boiler water supply heating and deaerating.

According to the utility model discloses a full waste heat recovery's of flue gas soda system, wherein, the system still includes exhaust-heat boiler water preheating device.

According to the utility model discloses a full waste heat recovery's of flue gas steam-water system, wherein, exhaust-heat boiler water preheating device is including adopting torch waste heat recovery device, the multistage flue gas water cooler flue gas thermoregulation/spark arrester of taking the fin of strengthening fin heat exchange tube structure and letting out explode excessive flue gas thermoregulation/spark arrester, to being less than or equal to 200 ℃ flue gas waste heat effective recovery, preheats the demineralized water with the heat energy of retrieving.

According to the utility model discloses a full waste heat recovery's of flue gas soda system, wherein, activity petticoat pipe and cover skirt adopt forced circulation mode.

According to the primary flue gas full waste heat recovery steam-water system of the utility model, the membrane water wall combined type waste heat recovery device with the independently replaceable heat pipe comprises an upper box body, a plurality of sections of waste heat recovery sections, a middle transition section and an ash bucket, wherein the upper box body is positioned above the waste heat recovery sections, the middle transition section is positioned between the adjacent waste heat recovery sections, the ash bucket is positioned at the tail end of the waste heat recovery sections,

the upper box body is provided with a high-temperature flue gas inlet, the shell of the waste heat recovery section is a membrane water-cooled wall, the membrane water-cooled wall of the waste heat recovery section is provided with a heat pipe which is inserted from the outside and can be replaced independently, and the heating surface of the heat pipe which can be replaced independently is coated with a heat-resistant and corrosion-resistant coating.

Based on the problems of the existing several converter primary dedusting processes, in order to realize safe, stable and reliable operation of a converter primary dedusting system, efficient recovery of all residual heat, stable recovery of clean dry gas, stable and ultralow emission of flue gas, saving of consumption of a large amount of water and steam, and complete elimination of smoke rain and corrosion of a gas recovery system, the utility model adopts a pure dry dedusting process, namely, in the whole treatment processes of cooling, dedusting and purifying of converter primary flue gas, recovery of clean dry gas, emission of flue gas and the like, an Evaporative Cooler (EC) is cancelled in the existing dry dedusting system and semi-dry dedusting system, an effective residual heat recovery device is adopted for substitution, water spraying directly into the high-temperature flue gas is not needed, evaporation heat absorption of water and steam latent heat are not needed to cool the high-temperature flue gas, and the existing converter primary dedusting OG method, the system and the system are fundamentally changed, The 'wet' nature of the new OG method, semi-dry method, dry method (LT method) and other dust removing processes is the dry dust removing in the real sense, and has significant meaning in the aspects of energy saving and environmental protection. Therefore, the flue gas temperature can be effectively reduced, and the sensible heat in the primary flue gas of the converter can be recovered to the maximum extent.

1. A pure dry type dust removal process is adopted, so that the consumption of water and steam is 0, and the total waste heat of the flue gas is recovered;

2. the method can effectively recover the flue gas waste heat to generate saturated steam, recover the converter flue gas waste heat to the maximum extent, stably produce steam for power generation or production and use, and has obvious energy-saving benefit.

Drawings

FIG. 1 is a schematic view of a steam-water system for recovering the total waste heat of primary flue gas of a converter according to the present invention;

FIG. 2 is a flow chart of a steam-water system for recycling the total waste heat of primary flue gas of the converter;

FIG. 3 shows a high pressure steam drum and a low pressure steam drum of the converter primary flue gas total waste heat recovery steam-water system of the present application;

fig. 4 is a schematic structural diagram of a membrane wall combined type waste heat recovery device with a heat pipe capable of being replaced independently.

Reference numerals:

101: a high pressure steam drum; 102: conveying the waste water into a heat accumulator; 104: a low pressure steam drum; 105: a water diversion header; 107: a deaerator;

5: the membrane type water-cooled wall combined waste heat recovery device can independently replace the heat pipe; 6: explosion venting overflow flue gas temperature regulating/flame arrester; 7: a flue gas temperature conditioning/flame arrestor; 9: a multi-stage flue gas water cooler with fins; 15: a torch waste heat recovery device with a reinforced fin heat exchange tube structure is adopted;

5-1: an upper box body; 5-2: a waste heat recovery section; 5-3: a middle transition section; 5-4: an ash hopper; 5-5: a gas shock wave soot blower; 5-6: a membrane wall; 5-7: a high temperature flue gas inlet; 5-8: an access hole door; 5-9: a heat pipe; 5-10: a barrier; 5-11: a cooled flue gas outlet; 5-12: a compressed nitrogen gas blowing device; 5-13: dust removal pneumatic conveying sender.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be described in detail and completely with reference to the following specific embodiments of the present application and the accompanying drawings. It should be apparent that the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The technical solutions provided by the embodiments of the present application are described in detail below with reference to the accompanying drawings.

As shown in figures 1, 2 and 3, the steam-water system for recovering the total waste heat of the primary flue gas of the converter according to the utility model comprises a movable smoke hood and a hood 2, a vaporization cooling flue 3, a membrane water wall combined type waste heat recovery device 5 which can independently replace a heat pipe, a water preheating device for a waste heat boiler, a high-pressure steam drum and a low-pressure steam drum,

the preheating device for water for the waste heat boiler comprises: the method comprises the following steps of effectively recovering the waste heat of the flue gas at the temperature of less than or equal to 200 ℃ by adopting a torch waste heat recovery device 15 with a reinforced fin heat exchange tube structure, a multi-stage finned flue gas water cooler 9, a flue gas temperature regulating/fire arrestor 7 and an explosion venting overflow flue gas temperature regulating/fire arrestor 6, and preheating softened water by using recovered heat energy;

the high-pressure evaporator system is composed of a high-pressure steam drum 101, a downcomer, a heat pipe evaporator at the upper part of the membrane water wall combined type waste heat recovery device 5 with the heat pipes capable of being replaced independently, a membrane water wall evaporator at the upper part of the membrane water wall combined type waste heat recovery device 5 with the heat pipes capable of being replaced independently and an ascending pipe, and the high-pressure evaporator system has the main function of generating 1.8MPa saturated steam. Water in the high-pressure steam drum 101 enters an evaporator of the evaporative cooling flue 3 through a downcomer to absorb heat of flue gas to form a steam-water mixture, the steam-water mixture enters the high-pressure steam drum 101 through an ascending pipe, and after the steam-water mixture is separated by a steam-water separator in the high-pressure steam drum 101, steam is conveyed into the heat accumulator 102 from the high-pressure steam drum 101. The main function of the high pressure evaporator system is to generate 1.8MPa saturated steam.

The heat pipe evaporator in the middle of the membrane water wall combined type waste heat recovery device 5 with the independently replaceable heat pipe forms an economizer, water from the water distribution and collection tank 105 is heated to 170 ℃, and then the water is sent into the high-pressure steam pocket 101;

the low-pressure steam pocket 104, the downcomer, the lower heat pipe evaporator of the membrane water wall combined type waste heat recovery device 5 with the independently replaceable heat pipes, the lower membrane water wall evaporator of the membrane water wall combined type waste heat recovery device 5 with the independently replaceable heat pipes, the riser and the like form a low-pressure evaporator system, and the low-pressure evaporator system has the main function of generating 0.4MPa saturated steam. Water in the low-pressure steam pocket 104 enters each evaporator through a downcomer to absorb heat of flue gas to form a steam-water mixture, the steam-water mixture enters the low-pressure steam pocket 104 through an ascending pipe, and generated low-pressure saturated steam is conveyed to a deaerator 107 to be used as boiler feed water for heating and deaerating.

The movable smoke hood and the hood skirt 2 adopt a forced circulation mode.

The steam-water system for recovering the full waste heat of the primary flue gas of the converter effectively cools the high-temperature flue gas by adopting the membrane type water-cooled wall combined waste heat recovery device which can independently replace the heat pipe, and recovers the waste heat of the primary flue gas of the converter to the maximum extent;

by means of the vaporization cooling flue, the membrane water wall combined type waste heat recovery device with the heat pipe capable of being replaced independently, the multistage combined flue gas waste heat recovery device with the reinforced fin heat exchange pipe structure, the explosion-venting overflow flue gas temperature adjusting/fire arrester and the torch waste heat recovery device with the reinforced fin heat exchange pipe structure, the total flue gas waste heat under the working states of converter oxygen blowing smelting and non-oxygen blowing smelting is effectively recovered.

As shown in fig. 4, the membrane wall combined type waste heat recovery device with the independently replaceable heat pipe comprises a round-square variable-diameter high-temperature flue gas upper box body 5-1, a plurality of sections of square waste heat recovery sections 5-2, a middle transition section 5-3 and an ash bucket 5-4, wherein the upper box body 5-1 is positioned above the waste heat recovery section 5-2; the intermediate transition section 5-3 is positioned between the adjacent waste heat recovery sections 5-2,

the upper box body 5-1 is provided with a high-temperature flue gas inlet 5-7, the upper box body 5-1 and each intermediate transition section 5-3 are respectively provided with an access hole door 5-8, and the access hole doors 5-8 are provided with a gas shock wave soot blowing device 5-5 for blowing and cleaning ash of the heat pipe; the shell of the waste heat recovery section 5-2 adopts a membrane water-cooled wall 5-6; the membrane water-cooled wall of the waste heat recovery section 5-2 is provided with an externally inserted heat pipe 5-9 which can be independently replaced; the heating surface of the heat pipe 5-9 which can be independently replaced adopts a supersonic speed electric arc spraying layer of heat-resistant, wear-resistant and corrosion-resistant special alloy coating. The externally inserted heat pipe 5-9 which can be replaced independently is fixed in an inserted sleeve arranged on the membrane water wall 5-6 of the waste heat recovery section 5-2 through a flange and a ceramic fiber bush welded on the heat pipe by fastening screws and gaskets;

the ash hopper 5-4 is positioned at the tail end of the waste heat recovery section, and a cooled flue gas outlet 5-11 is arranged at one side of the ash hopper 5-4 corresponding to the inlet of the waste heat recovery section 5-2; a set of barrier baffle plates 5-10 are arranged between the ash hopper 5-4 and the end section inlet of the waste heat recovery section 5-2 and the cooled flue gas outlet 5-11 and are used for effectively settling and filtering dust particles in the flue gas; the lower part of the ash bucket is provided with a dust-removing pneumatic conveying transmitter 5-13; 5-2 of each section of waste heat recovery is provided with a flame-retardant/explosion-proof compressed nitrogen injection device; and 5-12 compressed nitrogen blowing devices for fluidization, flame retardance and explosion prevention are arranged at the bottom 5-4 of the ash bucket.

The above description is only an example of the present application and is not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims (5)

1. A steam-water system for recovering the full afterheat of primary fume is composed of movable fume hood, cover skirt, vaporizing cooling flue, membrane-type water-cooled wall combined afterheat recovering unit with individually replaceable heat tubes, high-pressure steam drum, and low-pressure steam drum,

the high-pressure steam pocket, the downcomer, the heat pipe evaporator at the upper part of the membrane water-cooled wall combined type waste heat recovery device with the independently replaceable heat pipe, the membrane water-cooled wall evaporator at the upper part of the membrane water-cooled wall combined type waste heat recovery device with the independently replaceable heat pipe and the riser form a high-pressure evaporator system;

water in the high-pressure steam pocket enters an evaporator of the evaporative cooling flue through a descending pipe, absorbs heat of flue gas to form a steam-water mixture, enters the high-pressure steam pocket through an ascending pipe, is separated by a steam-water separator in the high-pressure steam pocket, and then steam is conveyed into a heat accumulator from the high-pressure steam pocket;

the heat pipe evaporator in the middle of the membrane water wall combined type waste heat recovery device with the independently replaceable heat pipes forms a coal economizer, water from the water dividing header is heated to 170 ℃, and then the water is sent to the high-pressure steam pocket;

the low-pressure steam pocket, the downcomer, the lower heat pipe evaporator of the membrane water wall combined type waste heat recovery device with the independently replaceable heat pipe, the lower membrane water wall evaporator of the membrane water wall combined type waste heat recovery device with the independently replaceable heat pipe, the riser and the like form a low-pressure evaporator system;

water in the low-pressure steam pocket enters each evaporator through a downcomer to absorb heat of flue gas to form a steam-water mixture, and low-pressure saturated steam generated by entering the low-pressure steam pocket through an ascending pipe is conveyed to a deaerator and used for boiler water supply heating and deaerating.

2. The primary flue gas total heat recovery steam-water system according to claim 1, further comprising a waste heat boiler water preheating device.

3. The primary flue gas full waste heat recovery steam-water system as claimed in claim 2, wherein the waste heat boiler water preheating device comprises a torch waste heat recovery device adopting a reinforced fin heat exchange tube structure, a multi-stage finned flue gas water cooler flue gas temperature adjusting/flame arrester and an explosion venting overflow flue gas temperature adjusting/flame arrester, the waste heat of the flue gas is effectively recovered at the temperature of less than or equal to 200 ℃, and the softened water is preheated by the recovered heat energy.

4. The steam-water system for primary flue gas total heat recovery according to claim 1, wherein the movable smoke hood and the hood skirt adopt a forced circulation mode.

5. The primary flue gas total waste heat recovery steam-water system according to claim 1, wherein the membrane water wall combined type waste heat recovery device with the independently replaceable heat pipe comprises an upper box body, a plurality of sections of waste heat recovery sections, a middle transition section and an ash bucket, wherein the upper box body is positioned above the waste heat recovery sections, the middle transition section is positioned between the adjacent waste heat recovery sections, the ash bucket is positioned at the tail end of the waste heat recovery sections,

the upper box body is provided with a high-temperature flue gas inlet, the shell of the waste heat recovery section is a membrane water-cooled wall, the membrane water-cooled wall of the waste heat recovery section is provided with a heat pipe which is inserted from the outside and can be replaced independently, and the heating surface of the heat pipe which can be replaced independently is coated with a heat-resistant and corrosion-resistant coating.

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