CN112063793B - A converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification - Google Patents

Abstract

The invention belongs to the field of energy conservation and environmental protection, and particularly relates to a converter primary pure dry dedusting system integrating full waste heat recovery, stability and fine purification. Comprises a vaporization cooling flue, a high-temperature phase-change heat storage device, a waste heat recovery system and an explosion-proof system. The converter gas is free from direct contact with water in the cooling process, the gas is free from water, the CO loss is reduced, the gas recovery amount is large, the conveying and the use are facilitated, and the gas quality is high. The full waste heat recovery device is utilized to recover the waste heat of the converter flue gas to the maximum extent, and steam is stably produced for power generation or production and use, so that the energy-saving benefit is obvious. Besides recovering heat and coal gas, various dust is mixed without water, is easy to separate, recover and recycle, does not cause secondary pollution and has no wastewater treatment cost.

Description

A converter one-step pure dry method dust removal system that integrates full waste heat recovery and stable fine purification

Technical Field

The present invention belongs to the field of energy conservation and environmental protection, and specifically relates to a converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification.

Background Art

As the main steelmaking process of steel enterprises, converter steelmaking produces gas mainly containing carbon monoxide, a small amount of carbon dioxide and other trace components during the blowing process, which also carries a large amount of iron oxide, metal iron particles, and other fine particles of solid dust. Therefore, improving the technical level of converter dust removal system, recycling and utilizing converter gas and recovering flue gas waste heat are of great significance for energy saving and consumption reduction in steelmaking, effectively controlling and reducing the emission of atmospheric pollutants in steelmaking, and alleviating environmental pollution.

The temperature of converter flue gas at the outlet is about 1400-1600℃, and the dust concentration is 70-200g/m³. After leaving the furnace, it is usually cooled to 800-1000℃ by vaporization cooling flue or water cooling flue, and then enters the flue gas dust removal system to reduce the dust concentration to meet the national emission standards and the requirements of gas users. At present, the domestic converter primary flue gas dust removal processes mainly include traditional OG method, new OG method, semi-dry method, and dry method (LT method).

At present, no matter which of the above-mentioned process systems is used for primary flue gas purification of converters, the common feature is that the high-temperature flue gas is cooled by absorbing the latent heat of vaporization through the evaporation of water. The dry method (LT method) dust removal also consumes a lot of steam due to the requirements of its own system. Although cooling the flue gas by consuming water is an efficient cooling method, it is a very energy-consuming method. Because the high-temperature flue gas coming out of the vaporization cooling flue itself is a high-grade thermal energy, not only does it not try to recover the heat it carries, but it also consumes a lot of other energy to cool it, resulting in a lot of energy waste, which is also the main reason for the formation of smoke plumes. For example, under general design conditions, the flue gas temperature coming out of the vaporization flue is between 800 and 1000°C. If the flue gas temperature is simply reduced to 500°C, the steam generated per ton of steel can reach 20kg, which can generate huge benefits.

There is always a high risk of gas explosion in dry dust removal, and electrostatic precipitators cannot avoid the problem of high-voltage flashover in the electric field, which leads to the problem of explosion relief in the electrostatic precipitator. In the actual production and operation process of the dry electrostatic precipitator system for primary flue gas in the converter, due to frequent explosion and smoke problems, the dry precipitator system for primary flue gas in the converter often cannot ensure stable flue gas emissions that meet the standards. At the same time, the explosion relief of the electrostatic precipitator also causes secondary pollution at the work station.

Because the flue gas is cooled by spraying water and steam, it contains a large amount of moisture, which causes corrosion to the flue gas duct, electrostatic precipitator plates and shells, gas pipelines, and gas recovery equipment.

Since oxygen blowing is not continuous during converter steelmaking, the evaporation cooling flue and waste heat recovery device of the converter primary dust removal system are always in a working state of alternating heating and cooling cycles, resulting in large alternating thermal stress on the evaporation cooling flue and waste heat recovery device. Under the action of alternating thermal stress, the service life of the evaporation cooling flue and waste heat recovery device is short, and the workload of daily maintenance and repair is large, which also has a great impact on converter steelmaking production to a certain extent.

The explosion relief devices installed in the existing converter primary dust removal system are all directly connected to the atmosphere. When explosion relief occurs in the system, it will also cause a certain degree of secondary pollution to the working environment.

Summary of the invention

The object of the present invention is to provide a converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification.

The converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification according to the present invention comprises a vaporization cooling flue, a high-temperature phase-change heat storage device, a waste heat recovery system, and an explosion-proof system.

in,

The high-temperature phase-change heat storage device comprises a circular shell and an ash hopper, wherein the shell comprises an upper box and a middle box, a high-temperature phase-change heat storage core is arranged in the middle box, the upper box is located at the upper part of the middle box with the high-temperature phase-change heat storage core, and the ash hopper is located below the middle box;

The upper box body is provided with a high-temperature flue gas outlet, the middle box body or the ash hopper is provided with a high-temperature flue gas inlet, a primary cyclone separation/airflow equalization device is provided at the high-temperature flue gas inlet, and the high-temperature flue gas inlet is connected along the tangent direction of the circular shell;

The straight pipe wall at the lower part of the dusty flue gas primary cyclone separation/airflow equalization device is provided with uniformly distributed airflow holes;

A dust ash pneumatic conveying transmitter device is provided at the lower part of the ash hopper;

The high-temperature phase-change heat storage core is a honeycomb tube bundle, and the gaps between it and the middle box body are all high-temperature flue gas flow channels;

A gas shock wave soot blowing device is provided in the upper box body, which is used to spray and clean the high-temperature flue gas flowing through the channel cavity wall;

The bottom of the ash hopper is provided with a compressed nitrogen blowing device for fluidization/flame retardation/explosion prevention;

The vortex area where the middle box, the ash hopper, and the high-temperature flue gas primary cyclone separation/airflow equalization device intersect is provided with a flame retardant/explosion-proof compressed nitrogen blowing device.

The waste heat recovery system comprises a membrane-type water-cooled wall combined waste heat recovery device with independently replaceable heat pipes, and the membrane-type water-cooled wall combined waste heat recovery device with independently replaceable heat pipes comprises an upper box body, multiple waste heat recovery sections, an intermediate transition section, and an ash hopper, wherein the upper box body is located above the waste heat recovery section, the intermediate transition section is located between adjacent waste heat recovery sections, and the ash hopper is located at the end of the waste heat recovery section.

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, and a heat pipe which can be replaced separately and inserted from the outside is provided on the membrane water-cooled wall of the waste heat recovery section, and the heating surface of the heat pipe which can be replaced separately is covered with a heat-resistant and corrosion-resistant coating.

The high-temperature flue gas is cooled and the waste heat is recovered at the same time through the vaporization cooling flue, the high-temperature phase-change heat storage device using the micro-encapsulation process and the membrane-type water-cooled wall combined waste heat recovery device with individually replaceable heat pipes. During this process, the high-temperature phase-change heat storage device using the micro-encapsulation process stores or releases heat.

According to the converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification of the present invention, the explosion prevention system includes a spring self-resetting explosion prevention device that can prevent the explosion dust from escaping, a jet draft device of the explosion overflow smoke capture and treatment system, and a temperature-adjusting flame arrester for the explosion escape smoke.

According to the converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification of the present invention, the spring self-resetting explosion-relief device capable of preventing the explosion-relief smoke from escaping comprises an escaped smoke capture hood shell and a spring self-resetting valve plate assembly, wherein:

The upper part of the outer smoke collection hood shell is provided with an outer smoke outlet, and the outer smoke outlet is connected to the smoke pipe of the explosion venting outer smoke collection and treatment system.

The spring self-resetting valve plate assembly includes a valve plate, a valve plate guide rod, a self-resetting spring group, and a self-resetting spring group fixing frame, wherein:

The spring self-resetting valve plate assembly is fixed to the lower part of the inner cavity of the escape capture shell through the valve plate guide rod; a valve plate guide rod and a self-resetting spring assembly fixing frame are arranged on the upper part of the valve plate guide rod, and the self-resetting spring assembly is fixed on the valve plate guide rod and the self-resetting spring assembly fixing frame, and the self-resetting spring assembly applies pressure to the valve plate evenly downward,

The lower part of the valve plate is provided with an explosion venting smoke inlet.

The valve plate of the spring self-resetting valve plate assembly is sealed with the flange surface on the inner side of the lower part of the shell body of the external smoke collection hood through a sealing ring.

According to the converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification of the present invention, the waste heat recovery system also includes a multi-stage combined flue gas waste heat recovery device using an enhanced fin heat exchange tube structure.

According to the present invention, the converter primary pure dry dust removal system integrates full waste heat recovery and stable fine purification, wherein the converter primary pure dry dust removal system includes a flue gas temperature control/flame arrester.

According to the present invention, a converter primary pure dry dust removal system that integrates full waste heat recovery and stable fine purification, wherein the converter primary pure dry dust removal system includes a pulse jet filter bag/filter cartridge type dust collector.

According to the converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification of the present invention, the high-pressure steam drum, the downcomer, the upper heat pipe evaporator of the membrane water-cooled wall combined waste heat recovery device with replaceable heat pipes, the upper membrane water-cooled wall evaporator and the riser of the membrane water-cooled wall combined waste heat recovery device with replaceable heat pipes constitute the high-pressure evaporator system; the low-pressure steam drum, the downcomer, the lower heat pipe evaporator of the membrane water-cooled wall combined waste heat recovery device with replaceable heat pipes, the lower membrane water-cooled wall evaporator and the riser of the membrane water-cooled wall combined waste heat recovery device with replaceable heat pipes constitute the low-pressure evaporator system.

According to the converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification of the present invention, the waste heat recovery system included in the converter primary pure dry dust removal system includes a torch waste heat recovery device adopting an enhanced fin heat exchange tube structure.

Beneficial Effects

1. The pulse jet filter bag/filter cartridge dust removal device with medium temperature/high temperature resistant filter material can eliminate the micro-explosion phenomenon often caused by electric dust sparks, making the system operation safer.

2. The pulse jet filter bag/filter cartridge dust removal device using medium-temperature/high-temperature resistant filter materials is more efficient and stable than other dust removal and purification methods, and can ensure stable recovery of clean dry coal gas and exhaust gas quality. The dust content of dry coal gas and exhaust gas is ≤10mg/ ^Nm3 .

3. No water is added during the whole dry dust removal process, the temperature of the recovered coal gas is low, the air volume of the primary fan is reduced, the fan consumes less power, and the environmental protection benefits of water and electricity saving are significant.

4. The converter gas has no direct contact with water during cooling, so the gas does not contain water, which reduces CO loss. The gas recovery volume is large, which is conducive to transportation and use, and the gas quality is high.

5. The full waste heat recovery device is used to recover the waste heat of converter flue gas to the maximum extent, and to stably produce steam for power generation or production use, with obvious energy-saving benefits.

6. In addition to recovering heat and gas, various dusts are not mixed with water and are easy to separate, recycle and reuse without causing secondary pollution and wastewater treatment costs.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic structural diagram of a converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification according to the present invention;

FIG2 is a schematic diagram of the structure of a high-temperature phase-change heat storage device;

FIG3 is a schematic structural diagram of a membrane water-cooled wall combined waste heat recovery device in which heat pipes can be replaced individually;

FIG. 4 is a schematic diagram of the structure of a spring self-resetting explosion relief device that can prevent explosion relief smoke and dust from escaping.

Reference numerals:

1 converter; 3: gasification cooling flue; 4: spring self-reset explosion relief device to prevent explosion-proof dust from escaping; 5: membrane water-cooled wall combined waste heat recovery device with individually replaceable heat pipes; 6: high-temperature phase change heat storage device; 23: jet draft device for the explosion-proof overflow flue gas capture and treatment system; 17: flue gas temperature control/flame arrester; 24: flue gas temperature control/flame arrester to ensure the pulse jet bag/cartridge dust collector at the rear of the dust removal system; 27: torch waste heat recovery device with enhanced fin heat exchange tube structure; 39: multi-stage combined flue gas waste heat recovery device with enhanced fin heat exchange tube structure;

2-1: High-temperature flue gas outlet of high-temperature phase-change heat storage device; 2-2: Upper box of high-temperature phase-change heat storage device; 2-4: Shell; 2-5: High-temperature phase-change heat storage core; 2-8: Middle box; 2-9: Ash hopper; 2-12: Compressed nitrogen injection device of high-temperature phase-change heat storage device; 2-15: High-temperature flue gas inlet of high-temperature phase-change heat storage device; 2-16: Primary cyclone separation/airflow equalization device for dusty flue gas; 2-17: High-temperature phase-change heat storage core installation and fixing seat; 2-18: Tube bundle and gap channel through which high-temperature flue gas flows

5-1: Upper box of combined waste heat recovery device; 5-2: Waste heat recovery section; 5-3: Intermediate transition section; 5-4: Ash hopper; 5-5: Gas shock wave soot blowing device; 5-6: Membrane water-cooled wall; 5-7: High-temperature flue gas inlet of combined waste heat recovery device; 5-8: Inspection hole door; 5-9: Heat pipe; 5-10: Blocking baffle; 5-11: Cooled flue gas outlet of combined waste heat recovery device; 5-12: Compressed nitrogen injection device of combined waste heat recovery device; 5-13: Pneumatic conveying transmitter of dust removal ash

4-2: Smoke duct of explosion venting and escaping smoke capture and treatment system; 4-2: Explosion venting and escaping smoke capture hood shell; 4-7: Self-reset spring assembly; 4-8: Valve plate guide rod and self-reset spring assembly fixing bracket; 4-9: Valve plate guide rod; 4-10: Valve plate; 4-14: Escaping smoke outlet; 4-15: Explosion venting and escaping smoke inlet.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

According to the present invention, the converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification includes a vaporization cooling flue, a high-temperature phase-change heat storage device, a waste heat recovery system, and an explosion-proof system. The waste heat recovery system includes a membrane-type water-cooled wall combined waste heat recovery device with replaceable heat pipes. The high-temperature flue gas passes through the vaporization cooling flue, the high-temperature phase-change heat storage device using a micro-encapsulation process, and the membrane-type water-cooled wall combined waste heat recovery device with replaceable heat pipes. The high-temperature flue gas is cooled and waste heat is recovered at the same time. During this process, the high-temperature phase-change heat storage device using a micro-encapsulation process stores or releases heat.

The steam-water system of the vaporization cooling flue adopts a composite circulation cooling method combining natural circulation and forced circulation. The vaporization cooling flue of the converter flue gas full dry waste heat recovery and bag dust removal system is basically the same as the traditional vaporization cooling flue, which is a mature technology, but it needs to be partially modified according to the characteristics of the full dry dust removal system.

When the high-temperature phase-change heat storage device is in the converter oxygen blowing smelting working state (at this time, the flue gas temperature is the highest and the flue gas volume is the largest), the high-temperature flue gas enters the high-temperature phase-change heat storage device along the tangent direction of the box body through the inlet provided in the middle box body or the ash hopper, and the high-temperature flue gas is primary separated and purified by the primary cyclone separation/airflow equalization device provided at the inlet. Then, the high-temperature flue gas rises in the cylinder body and flows through the high-temperature phase-change heat storage core provided in the high-temperature phase-change heat storage device. The high-temperature phase-change heat storage material is packaged in the honeycomb, circular or square cavity of the high-temperature phase-change heat storage device through the micro-encapsulation process. In the constant high-temperature section (i.e., 700 —850℃), the high-temperature phase change heat storage material filled in the high-temperature heat storage core undergoes phase change to absorb a large amount of heat from the high-temperature flue gas in time, and then flows out through the high-temperature flue gas outlet provided on the upper box of the high-temperature phase change heat storage device; when the converter is in the working state of smelting without oxygen blowing (the temperature of the flue gas passing through is relatively low and the amount of flue gas is small at this time), also in the constant high-temperature section (i.e. 700-850℃), the high-temperature phase change heat storage material undergoes phase change and quickly releases a large amount of heat to the flue gas passing through it, heating the passing flue gas, and the high-temperature flue gas after heating flows out from the high-temperature flue gas outlet provided on the upper box of the high-temperature phase change heat storage device. As a result, the effect of alternating thermal stress of the high-temperature dust removal device and the waste heat recovery device in the dust removal system is avoided, the service life of the high-temperature dust removal device and the waste heat recovery device is effectively improved, the workload of daily maintenance and repair is minimized, and the stability and reliability of converter steelmaking production is ensured.

It also forms a constant temperature system together with the gas burner, avoiding the impact of the reciprocating rapid heating and cooling of the vaporization cooling flue and the waste heat recovery device due to the particularity of the converter steelmaking production process.

The high-temperature phase-change heat storage device can form a constant temperature system for the converter primary pure dry dust removal system with a gas burner, a gas burner blower, a water-cooled two-way high-temperature reversing valve, and a water-cooled three-way high-temperature reversing valve. It is a very critical system for the converter primary pure dry dust removal system that integrates full waste heat recovery and stable fine purification. The main function of this system is to minimize the impact of reciprocating rapid heating and cooling on the vaporization cooling flue and waste heat recovery device of the converter primary dust removal system in view of the process characteristics of converter steelmaking (i.e., intermittent production).

The membrane water-cooled wall combined waste heat recovery device (i.e., waste heat boiler) with independently replaceable heat pipes adopts a convection heat exchange surface to solve a series of problems such as preventing local accumulation and explosion of coal gas, as well as dust accumulation, abrasion, dust cleaning, heat exchange, etc. The device recovers the waste heat of high-temperature flue gas through independently arranged heat pipes and membrane water-cooled walls and other heat exchange devices, and at the same time plays the role of cooling the high-temperature flue gas and initially settling and separating the dust in the flue gas.

The flue gas temperature regulator/flame arrester ensures the safe, stable and reliable operation of the pulse jet bag/cartridge dust collector at the rear of the dust removal system. It isolates the fire in the flue gas and eliminates one of the three elements of combustible gas explosion (i.e., fire with sufficient energy), thereby fundamentally avoiding the occurrence of explosion. The flue gas temperature regulator/flame arrester is also equipped with an explosion relief device to ensure that even if an explosion occurs, it will not cause damage or loss to the system equipment, ensuring the safety and efficiency of the project. In addition, the flue gas temperature regulator/flame arrester uses forced water cooling to cool the flue gas. Softened water is used to cool the flue gas. After being heated to a certain degree, the softened water is used as water supply for the evaporator of the waste heat recovery device, thereby realizing the full recovery of the waste heat of the primary flue gas of the converter.

The converter flue gas full waste heat recovery and bag dust removal system is a fully dry process. It uses explosion-proof medium-temperature or high-temperature resistant filter material and ultra-low emission pulse jet filter bag/cartridge dust collector to avoid the unsafe factor of micro-explosion caused by the electric spark of the electrostatic precipitator, and avoids problems such as bag sticking through the high-temperature flue gas dry waste heat recovery cooling method. The dust removal effect is stable and better than the electrostatic precipitator and wet dust removal process. A dust collection and transportation system is set at the bottom of the dust removal system.

The multi-stage combined flue gas waste heat recovery device with enhanced fin heat exchange tube structure is used to realize full waste heat recovery of converter primary flue gas. It ensures the required temperature for clean dry gas recovery and absorbs waste heat from flue gas to the maximum extent. It uses forced water cooling to cool the flue gas. Softened water is used for cooling. After being heated to a certain degree, the softened water is used as water supply for the evaporator of the waste heat recovery device, thereby realizing full recovery of converter primary flue gas waste heat.

The flare waste heat recovery device with enhanced fin heat exchange tube structure is used to realize full waste heat recovery of converter primary flue gas. It adopts forced water cooling to realize effective recovery of heat from flue gas flare. Softened water is used as water supply for evaporator of waste heat recovery device after being heated to a certain degree, thereby realizing full recovery of converter primary flue gas waste heat.

The explosion venting smoke escaping and treatment system includes a spring self-resetting explosion venting device that can prevent the explosion venting smoke from escaping, a smoke duct of the explosion venting smoke collection and treatment system, a jet draft device of the explosion venting smoke collection and treatment system, and an explosion venting smoke escaping temperature control/flame arrester. The main function is to effectively capture the smoke escaping at the moment of explosion venting, and to cool it down, flame retardant it, and explosion-proof it, and then send it into the system's explosion-proof, medium-temperature-resistant or high-temperature-resistant filter material ultra-low emission pulse jet filter bag/filter cartridge type dust collector for purification and filtration before being discharged together with the system's mainstream smoke.

The vaporization cooling flue, the membrane water-cooled wall combined waste heat recovery device with independently replaceable heat pipes, the high-pressure steam drum and the low-pressure steam drum constitute the steam-water system for full waste heat recovery of primary flue gas, among which:

The high-pressure steam drum, the downcomer, the upper heat pipe evaporator of the membrane-type water-cooled wall combined waste heat recovery device with heat pipes that can be replaced separately, the upper membrane-type water-cooled wall evaporator of the membrane-type water-cooled wall combined waste heat recovery device with heat pipes that can be replaced separately, and the riser constitute a high-pressure evaporator system;

The water in the high-pressure drum enters the evaporator of the vaporization cooling flue through the downcomer, absorbs the heat of the flue gas to form a steam-water mixture, and enters the high-pressure drum through the riser. After being separated by the steam-water separator in the high-pressure drum, the steam is transported from the high-pressure drum to the heat accumulator;

The heat pipe evaporator in the middle of the membrane water-cooled wall combined waste heat recovery device with independently replaceable heat pipes constitutes an economizer, which heats the water coming out of the water distribution header to 170°C and then sends it to the high-pressure steam drum;

The low-pressure steam drum, the downcomer, the lower heat pipe evaporator of the membrane-type water-cooled wall combined waste heat recovery device with independently replaceable heat pipes, the lower membrane-type water-cooled wall evaporator of the membrane-type water-cooled wall combined waste heat recovery device with independently replaceable heat pipes, and the riser constitute a low-pressure evaporator system;

The water in the low-pressure drum enters each evaporator through the downcomer, absorbs the heat of the flue gas to form a steam-water mixture, and enters the low-pressure drum through the riser to generate low-pressure saturated steam which is transported to the deaerator and used as boiler feed water for heating and deoxygenation.

Together with the flare waste heat recovery device with enhanced finned heat exchange tube structure, multi-stage flue gas water cooler with fins, and other waste heat recovery devices, the whole waste heat of flue gas in the converter oxygen blowing smelting and non-oxygen blowing smelting working conditions can be effectively recovered to generate saturated steam, effectively recover the waste heat of flue gas ≤200℃, and use the recovered heat energy to preheat softened water.

The operation mode of the converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification of the present invention is:

1. Under oxygen blowing smelting working state

Before the converter carries out oxygen blowing smelting, the water-cooled three-way high-temperature reversing valve operates to connect the high-temperature flue gas outlet of the vaporization cooling flue with the high-temperature phase-change heat storage device using the micro-encapsulation process. At the same time, the cold two-way high-temperature reversing valve operates to connect the high-temperature flue gas outlet of the "high-temperature phase-change heat storage device using the micro-encapsulation process" with the "membrane-type water-cooled wall combined waste heat recovery device with replaceable heat pipes separately." During the oxygen blowing smelting operation of the converter, under the suction action of the axial flow fan, the high-temperature flue gas generated by the converter oxygen blowing passes through the vaporization cooling flue, the high-temperature flue gas pipeline, the high-temperature phase-change heat storage device using the micro-encapsulation process, the membrane-type water-cooled wall combined waste heat recovery with replaceable heat pipes separately, the flue gas temperature control/flame arrester, the explosion-proof medium-temperature or high-temperature resistant filter material ultra-low emission pulse jet filter bag/filter cartridge dust collector, the flue gas pipeline, and the "multi-stage combined flue gas waste heat recovery device with enhanced fin heat exchange tube structure." During this period, the high-temperature flue gas is cooled, the waste heat is recovered, and ultra-fine purification and filtration are carried out. At the same time, a high-temperature phase change heat storage device with micro-encapsulation technology is used to store heat.

The flue gas from the front and back sections of oxygen-blowing smelting will be recovered by coal gas and switched by flue gas release switching valves, and released into the atmosphere through the release chimney, the release gas torch, and the torch waste heat recovery device with enhanced fin heat exchange tube structure.

The clean dry coal gas in the middle stage of oxygen blowing smelting will be switched through the gas recovery/flue gas release switching valve, and the coal gas will be collected into the gas tank through the gas recovery pipeline.

2. Non-oxygen blowing smelting working state

When the converter is not carrying out oxygen blowing smelting, the water-cooled three-way high-temperature reversing valve in the system is actuated to respectively connect the high-temperature flue gas outlet of the vaporization cooling flue with the membrane-type water-cooled wall combined waste heat recovery device with individually replaceable heat pipes and the high-temperature phase-change heat storage device using micro-encapsulation technology with the gas burner. At the same time, the water-cooled two-way high-temperature reversing valve in the system is actuated to connect the gas burner blower with the high-temperature phase-change heat storage device using micro-encapsulation technology. During the non-oxygen smelting operation of the converter, under the suction of the axial flow fan, the high-temperature flue gas generated by the air blown in by the gas burner blower passes through the "high-temperature phase change heat storage device using micro-encapsulation technology-6" and the high-temperature flue gas generated by the gas CO injected into the gas burner passes through the vaporization cooling flue, high-temperature flue gas pipeline, the membrane water-cooled wall combined waste heat recovery device with replaceable heat pipes, the flue gas temperature regulator/flame arrester, the explosion-proof medium-temperature or high-temperature filter material ultra-low emission pulse jet filter bag/filter cartridge dust collector, the flue gas pipeline, and the multi-stage combined flue gas waste heat recovery device with enhanced fin heat exchange tube structure. During this period, the high-temperature flue gas is cooled/waste heat recovered and ultra-finely purified and filtered. The treated flue gas will be switched by the gas recovery/flue gas release switching valve and released into the atmosphere through the release chimney, the release gas torch, and the torch waste heat recovery device with enhanced fin heat exchange tube structure.

3. Waste heat recovery

Through the vaporization cooling flue, the membrane water-cooled wall combined waste heat recovery device with replaceable heat pipes, the flue gas temperature control/flame arrester, the multi-stage combined flue gas waste heat recovery device with enhanced fin heat exchange tube structure, the explosion venting and overflow flue gas temperature control/flame arrester, the "torch waste heat recovery device with enhanced fin heat exchange tube structure, and the waste heat recovery steam-water system and other devices, the whole waste heat of the flue gas under the working conditions of oxygen blowing smelting and non-oxygen blowing smelting of the converter is effectively recovered.

4. Effective treatment of the smoke and dust generated by the explosion relief valve

The dust-proof overflow spring self-resetting explosion relief valve device automatically vents the explosion when the system device is in an abnormal state. The resulting overflow smoke and dust will be treated through the explosion venting overflow smoke capture and treatment system smoke duct, explosion venting overflow smoke temperature control/flame arrester, and explosion venting overflow smoke capture and treatment system jet draft device and other devices, and then introduced into the explosion-proof medium-temperature or high-temperature resistant filter material ultra-low emission pulse jet filter bag/filter cartridge type dust collector for purification and filtration.

By utilizing the technical solution of the present invention, a pure dry dust removal process is adopted, so that the consumption of water and steam is "0"; by adding high-temperature phase-change heat accumulators, gas burners, water-cooled high-temperature valves, gas burner blowers, and water-cooled two-way/three-way reversing valves and other devices using a micro-encapsulation process, they are switched between the converter oxygen blowing smelting working state and the non-oxygen blowing smelting working state, thereby ensuring that high-temperature flue gas is continuously generated in the vaporization cooling flue, solving the thermal expansion and contraction problems caused by rapid cooling and heating of the vaporization cooling flue and the waste heat recovery device caused by intermittent production of the steelmaking converter, extending the service life of the flue and the waste heat recovery device, and increasing the steam recovery amount.

The high-temperature phase-change heat accumulator using micro-encapsulation technology has a high heat storage density and can effectively realize the storage and release of thermal energy above ≥800℃, and can achieve the storage and release of thermal energy basically constant within the set temperature range, thereby solving the contradiction between the mismatch between the supply and demand of thermal energy in time and intensity caused by the particularity of the converter steelmaking process.

By setting up a dust-proof spring self-resetting explosion-relief valve device, a collection pipeline, and corresponding subsequent processing equipment, the smoke and dust that overflows when the explosion-relief valve is vented can be effectively recovered and processed, preventing the occurrence of secondary pollution problems that may be caused by the explosion.

By adopting a membrane water-cooled wall combined waste heat recovery device with individually replaceable heat pipes, the high-temperature flue gas is effectively cooled and the waste heat of the converter primary flue gas is recovered to the maximum extent.

The explosion-proof ultra-low emission pulse bag dust collector is used to perform ultra-fine filtration treatment on the primary flue gas of the converter, which completely avoids the explosion problem caused by electrostatic dust removal power generation, ensures the safe and stable operation of the primary dust removal system of the converter, and realizes the stable recovery of clean dry gas and the stable dust content of the discharged flue gas at ≤10mg/Nm³.

The corrosion problems of gas pipelines and equipment facilities are minimized, and the occurrence of smoke and plume release is completely avoided.

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

Example

As shown in Figure 1, there are a vaporization cooling flue 2, a high-temperature phase-change heat storage device 6, a waste heat recovery system, and an explosion-proof system. The waste heat recovery system includes a membrane-type water-cooled wall combined waste heat recovery device 5 whose heat pipes can be replaced separately. The high-temperature flue gas generated by the converter 1 passes through the vaporization cooling flue 2, the high-temperature phase-change heat storage device 5 and the membrane-type water-cooled wall combined waste heat recovery device 5 whose heat pipes can be replaced separately, and is cooled and waste heat is recovered at the same time. During this process, the high-temperature phase-change heat storage device 6 stores or releases heat.

Before the converter carries out oxygen blowing smelting, the water-cooled three-way high-temperature reversing valve is actuated to connect the high-temperature flue gas outlet of the vaporization cooling flue 3 with the high-temperature phase-change heat storage device 6. At the same time, the cold two-way high-temperature reversing valve is actuated to connect the high-temperature flue gas outlet of the high-temperature phase-change heat storage device 6 with the membrane water-cooled wall combined waste heat recovery device 5 whose heat pipes can be replaced separately. During the oxygen blowing smelting work of the converter 1, under the suction effect of the axial flow fan, the high-temperature flue gas generated by the oxygen blowing of the converter passes through the vaporization cooling flue 2, the high-temperature flue gas pipeline, the high-temperature phase change heat storage device 6, the membrane water-cooled wall combined waste heat recovery device 5 with individually replaceable heat pipes, the flue gas temperature control/flame arrester 17, the explosion-proof medium-temperature or high-temperature resistant filter material ultra-low emission pulse jet filter bag/filter cartridge type dust collector 24, the flue gas pipeline, and the "multi-stage combined flue gas waste heat recovery device 39 with enhanced fin heat exchange tube structure". During the period, the high-temperature flue gas is cooled, the waste heat is recovered and ultra-finely purified and filtered. At the same time, the high-temperature phase change heat storage device with micro-encapsulation technology is used for heat storage.

The flue gas from the front and back stages of oxygen blowing smelting will be switched through the gas recovery and flue gas release switching valves, and released into the atmosphere through the release chimney, the release gas torch, and the torch waste heat recovery device 27 with an enhanced fin heat exchange tube structure.

The clean dry coal gas in the middle stage of oxygen blowing smelting will be switched through the gas recovery/flue gas release switching valve, and the coal gas will be collected into the gas tank through the gas recovery pipeline.

When the converter is not carrying out oxygen blowing smelting, the water-cooled three-way high-temperature reversing valve in the system operates to connect the high-temperature flue gas outlet of the vaporization cooling flue 2 with the membrane water-cooled wall combined waste heat recovery device 5 with individually replaceable heat pipes, and the high-temperature phase-change heat storage device 6 with the gas burner. At the same time, the water-cooled two-way high-temperature reversing valve in the system operates to connect the gas burner blower with the high-temperature phase-change heat storage device. During the non-oxygen smelting operation of converter 1, under the suction of the axial flow fan, the high-temperature flue gas generated by the high-temperature phase-change heat storage device preheating the air blown in by the gas burner blower and the gas CO injected into the gas burner is passed through the vaporization cooling flue, high-temperature flue gas pipeline, the membrane water-cooled wall combined waste heat recovery device with replaceable heat pipes, the flue gas temperature regulator/flame arrester, the explosion-proof medium-temperature or high-temperature filter material ultra-low emission pulse jet filter bag/cartridge dust collector, the flue gas pipeline, and the multi-stage combined flue gas waste heat recovery device with enhanced fin heat exchange tube structure. During this period, the high-temperature flue gas is cooled/waste heat recovered and ultra-finely purified and filtered. The treated flue gas will be switched by the gas recovery/flue gas release switching valve and released into the atmosphere through the release chimney, the release gas torch, and the torch waste heat recovery device with enhanced fin heat exchange tube structure.

Through the vaporization cooling flue, the membrane water-cooled wall combined waste heat recovery device with separately replaceable heat pipes, the flue gas temperature control/flame arrester, the multi-stage combined flue gas waste heat recovery device with enhanced fin heat exchange tube structure, the explosion venting and overflow flue gas temperature control/flame arrester, the torch waste heat recovery device with enhanced fin heat exchange tube structure, and the waste heat recovery steam-water system, the whole waste heat of the flue gas under the converter oxygen blowing smelting and non-oxygen blowing smelting working conditions can be effectively recovered.

The explosion-proof system includes a spring-loaded self-resetting explosion-proof device 4 which can prevent the escape of explosion-proof smoke and dust. The spring-loaded self-resetting explosion-proof device 4 which can prevent the escape of explosion-proof smoke and dust will automatically vent when the system is in an abnormal state. The resulting overflowing smoke and dust will be processed by the smoke duct of the explosion-proof overflowing smoke capture and treatment system, the explosion-proof overflowing smoke temperature regulator/flame arrester, and the explosion-proof overflowing smoke capture and treatment system jet draft device 23, and then introduced into the pulse-jet bag/cartridge dust collector 24 for purification and filtration.

Example

As shown in FIG2 , the high-temperature phase-change heat storage device comprises a circular shell 2-4 and an ash hopper 2-9, wherein the shell comprises an upper box 2-2 and a middle box 2-8, a high-temperature phase-change heat storage core 2-5 is arranged in the middle box 2-8, and the upper box 2-2 is located on the upper part of the high-temperature phase-change heat storage core 2-5 in the middle box 2-8; the middle box 2-8 and the upper box 2-2 can be opened to install, replace, maintain and repair the high-temperature phase-change heat storage core 2-5 arranged in the middle box; the ash hopper 2-9 is located below the middle box 2-8;

The upper box body 2-2 is provided with a high-temperature flue gas outlet 2-1, and the middle box body 2-8 or the ash hopper 2-9 is provided with a high-temperature flue gas inlet 2-15. The high-temperature flue gas inlet 2-15 is connected along the tangent direction of the circular shell, and together with the dust-containing flue gas primary cyclone separation/airflow equalization device 2-16 arranged in the middle box body 2-8 or the ash hopper 2-9, the high-temperature dust-containing flue gas entering the dust collector is initially separated and settled;

The dust-containing flue gas primary cyclone separation/airflow equalization device 2-16 has uniformly distributed airflow holes (∮20-30mm holes) on the lower straight section of the pipe wall, and the opening rate is 40-50%;

The lower part of the ash hopper 2-9 is provided with a dust removal ash pneumatic conveying transmitter device;

A "honeycomb-shaped" high-temperature phase-change heat storage core is arranged in the middle box through a high-temperature phase-change heat storage core mounting and fixing seat 2-17; the "honeycomb-shaped" tube bundle of the high-temperature phase-change heat storage core and the gap between it and the middle box are both high-temperature flue gas flow passages; a gas shock wave soot blowing device is arranged in the upper box, which is used to spray and clean the cavity wall of the high-temperature flue gas flow passage of the high-temperature phase-change heat storage core fixed in the middle box;

The bottom of the ash hopper is provided with a compressed nitrogen blowing device 2-12 for fluidization, flame retardancy and explosion prevention;

The "vortex area" where the middle box, ash hopper, and high-temperature flue gas primary cyclone separation/airflow equalization device intersect is provided with a compressed nitrogen blowing device 2-12 for flame retardancy and explosion prevention.

The shell and the inner wall of the ash hopper of the high-temperature phase-change heat storage device are provided with a high-temperature resistant protective layer, and the outer wall is provided with a heat-insulating cotton and a protective plate layer.

The internal components of the high-temperature phase-change heat storage device, such as the housing, the high-temperature phase-change heat storage core mounting base, and the dust-containing flue gas primary cyclone separation/airflow equalization device, are all made of high-temperature resistant stainless steel.

According to the high-temperature phase-change heat storage device suitable for the converter steelmaking dust removal system of the present invention, the high-temperature phase-change heat storage core is obtained by filling the phase-change heat storage material into a high-temperature phase-change heat storage device shell with multiple tube bundles in a "honeycomb shape", and then vacuuming the high-temperature phase-change heat storage device through an exhaust head.

When the converter is in the oxygen blowing smelting working state, the flue gas temperature and the flue gas volume passing through at this time are the highest, and the high-temperature flue gas enters the high-temperature phase change heat storage device along the tangent direction of the box through the inlet arranged in the middle box or the ash hopper, and the high-temperature flue gas is primarily separated and purified by the primary cyclone separation/airflow equalization device arranged at the inlet. Then, the high-temperature flue gas rises in the cylinder and flows through the high-temperature phase change heat storage core arranged in the high-temperature phase change heat storage device. In the constant high temperature section (i.e. 700-850℃), the high-temperature phase change heat storage material filled in the high-temperature heat storage core undergoes phase change to absorb a large amount of heat of the high-temperature flue gas in time, and then flows out through the high-temperature flue gas outlet arranged on the upper box of the high-temperature phase change heat storage device.

When the converter is in the working state of smelting without oxygen blowing, the temperature of the flue gas passing through is relatively low and the amount of flue gas is small. Similarly, in the constant high temperature section (i.e. 700-850℃), the high-temperature phase change heat storage material rapidly releases a large amount of heat to the flue gas passing through it when the phase change occurs, thereby heating the passing flue gas. The heated high-temperature flue gas flows out from the high-temperature flue gas outlet arranged on the upper box of the high-temperature phase change heat storage device.

Example

As shown in FIG3 , the membrane water-cooled wall combined waste heat recovery device with individually replaceable heat pipes comprises a round-square variable diameter high-temperature flue gas upper box 5-1, a multi-section square waste heat recovery section 5-2, an intermediate transition section 5-3, and an ash hopper 5-4, wherein the upper box 5-1 is located above the waste heat recovery section 5-2; the intermediate transition section 5-3 is located between adjacent waste heat recovery sections 5-2,

The upper box body 5-1 is provided with a high-temperature flue gas inlet 5-7, and the upper box body 5-1 and each intermediate transition section 5-3 are respectively provided with an inspection hole door 5-8, and a gas shock wave soot blowing device 5-5 is provided on the inspection hole door 5-8, which is used to spray and clean 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 and individually replaceable heat pipe 5-9; the heating surface of the individually replaceable heat pipe 5-9 is sprayed with a layer of heat-resistant, wear-resistant and corrosion-resistant special alloy coating by supersonic arc spraying. The externally inserted and individually replaceable heat pipe 5-9 is fixed to the insertion sleeve installed on the membrane water-cooled wall 5-6 of the waste heat recovery section 5-2 by fastening screws and washers through the flange welded on the heat pipe and the ceramic fiber bushing;

The ash hopper 5-4 is located at the end of the waste heat recovery section, and a cooled flue gas outlet 5-11 is provided on the side of the ash hopper 5-4 corresponding to the inlet of the waste heat recovery section 5-2; a set of blocking baffles 5-10 is provided in the ash hopper 5-4 and between the last section inlet of the waste heat recovery section 5-2 and the cooled flue gas outlet 5-11, for effectively settling and filtering dust particles in the flue gas; a dust removal ash pneumatic conveying transmitter 5-13 is provided at the lower part of the ash hopper; each section of the waste heat recovery 5-2 is provided with a flame retardant/explosion-proof compressed nitrogen blowing device; the bottom 5-4 of the ash hopper is provided with a compressed nitrogen blowing device 5-12 for fluidization, flame retardancy and explosion-proof.

Example

As shown in Figure 4, a spring self-resetting explosion-proof device for preventing explosion-proof smoke from escaping includes an explosion-proof smoke collection cover shell 4-6 and a spring self-resetting valve plate assembly, wherein the shell includes an escaped smoke outlet 4-14 arranged on the upper part of the explosion-proof smoke collection cover shell, and the escaped smoke outlet 4-14 is connected to the smoke duct 4-2 of the explosion-proof smoke collection and treatment system; an explosion-proof smoke inlet 4-15 is arranged at the lower part of the explosion-proof smoke collection shell 4-6 (i.e., the lower part of the valve plate of the spring self-resetting valve plate assembly); the spring self-resetting valve plate assembly is fixed to the explosion-proof smoke collection cover shell 4-6 by a valve plate guide rod 4-9. The lower part of the inner cavity of the capture shell 4-6; the spring self-resetting valve plate assembly valve plate 4-10 is sealed with the inner flange surface of the lower part of the shell through a sealing ring; the spring self-resetting valve plate assembly is provided with a valve plate guide rod and a self-resetting spring group fixing frame 4-8 on the upper part of the valve plate guide rod 4-9; the self-resetting spring group 4-7 is fixed on the valve plate guide rod and the self-resetting spring group fixing frame 4-8, and the self-resetting spring group 4-7 applies balanced pressure downward to the valve plate; the spring self-resetting explosion-proof device that can prevent the explosion-proof smoke from escaping is connected and fixed to the explosion-proof port flange of the process device through its lower flange by a fastener group.

The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. 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 (6)

1. A converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification, characterized in that the converter primary pure dry dust removal system includes a vaporization cooling flue, a high-temperature phase change heat storage device, a waste heat recovery system, and an explosion-proof system. in, The high-temperature phase-change heat storage device comprises a circular shell and an ash hopper, wherein the shell comprises an upper box and a middle box, a high-temperature phase-change heat storage core is arranged in the middle box, the upper box is located at the upper part of the middle box with the high-temperature phase-change heat storage core, and the ash hopper is located below the middle box; The upper box body is provided with a high-temperature flue gas outlet, the middle box body or the ash hopper is provided with a high-temperature flue gas inlet, a primary cyclone separation and airflow equalization device is provided at the high-temperature flue gas inlet, and the high-temperature flue gas inlet is connected along the tangent direction of the circular shell; The straight section pipe wall at the lower part of the primary cyclone separation and airflow equalization device is provided with uniformly distributed airflow holes; A dust ash pneumatic conveying transmitter device is provided at the lower part of the ash hopper; The high-temperature phase-change heat storage core is a honeycomb tube bundle, and the gaps between it and the middle box body are all high-temperature flue gas flow channels; A gas shock wave soot blowing device is provided in the upper box body, which is used to spray and clean the high-temperature flue gas through the cavity wall of the channel; The bottom of the ash hopper is provided with a compressed nitrogen blowing device for fluidization, flame retardancy and explosion prevention; The middle box, the ash hopper, and the vortex area where the high-temperature flue gas primary cyclone separation and the airflow equalization device intersect are provided with a compressed nitrogen injection device for flame retardancy and explosion prevention. The waste heat recovery system comprises a membrane-type water-cooled wall combined waste heat recovery device with independently replaceable heat pipes, and the membrane-type water-cooled wall combined waste heat recovery device with independently replaceable heat pipes comprises an upper box body, multiple waste heat recovery sections, an intermediate transition section, and an ash hopper, wherein the upper box body is located above the waste heat recovery section, the intermediate transition section is located between adjacent waste heat recovery sections, and the ash hopper is located at the end of the waste heat recovery section. 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, and a heat pipe which can be replaced separately and inserted from the outside is provided on the membrane water-cooled wall of the waste heat recovery section, and the heating surface of the heat pipe which can be replaced separately is covered with a heat-resistant and corrosion-resistant coating. The high-temperature flue gas is cooled and the waste heat is recovered at the same time through the vaporization cooling flue, the high-temperature phase-change heat storage device using the micro-encapsulation process and the membrane-type water-cooled wall combined waste heat recovery device with replaceable heat pipes. In this process, the high-temperature phase-change heat storage device using the micro-encapsulation process stores or releases heat. The explosion prevention and venting system includes a spring self-resetting explosion venting device that can prevent the explosion venting smoke from escaping, a jet air induction device for the explosion venting smoke collection and treatment system, and a temperature-adjusting flame arrester for the explosion venting smoke. The spring self-resetting explosion relief device capable of preventing explosion relief smoke from escaping comprises an escaped smoke capture hood shell and a spring self-resetting valve plate assembly, wherein: The upper part of the outer smoke collection hood shell is provided with an outer smoke outlet, and the outer smoke outlet is connected to the smoke pipe of the explosion venting outer smoke collection and treatment system. The spring self-resetting valve plate assembly includes a valve plate, a valve plate guide rod, a self-resetting spring group, and a self-resetting spring group fixing frame, wherein: The spring self-resetting valve plate assembly is fixed to the lower part of the inner cavity of the outer smoke collection cover shell through the valve plate guide rod; a valve plate guide rod and a self-resetting spring assembly fixing frame are arranged on the upper part of the valve plate guide rod, and the self-resetting spring assembly is fixed on the valve plate guide rod and the self-resetting spring assembly fixing frame, and the self-resetting spring assembly applies pressure to the valve plate evenly downward, The lower part of the valve plate is provided with an explosion venting smoke inlet. The valve plate of the spring self-resetting valve plate assembly is sealed with the flange surface on the inner side of the lower part of the shell body of the external smoke collection hood through a sealing ring. 2. According to claim 1, the converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification is characterized in that the waste heat recovery system also includes a multi-stage combined flue gas waste heat recovery device using an enhanced fin heat exchange tube structure. 3. According to claim 1, the converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification is characterized in that the converter primary pure dry dust removal system includes a flue gas temperature regulating flame arrester. 4. According to claim 1, the converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification is characterized in that the converter primary pure dry dust removal system includes pulse jet filter bags and cartridge dust collectors. 5. The converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification according to claim 1 is characterized in that the high-pressure steam drum, the downcomer, the upper heat pipe evaporator of the membrane water-cooled wall combined waste heat recovery device with replaceable heat pipes, the upper membrane water-cooled wall evaporator and the riser of the membrane water-cooled wall combined waste heat recovery device with replaceable heat pipes constitute a high-pressure evaporator system; the low-pressure steam drum, the downcomer, the lower heat pipe evaporator of the membrane water-cooled wall combined waste heat recovery device with replaceable heat pipes, the lower membrane water-cooled wall evaporator and the riser of the membrane water-cooled wall combined waste heat recovery device with replaceable heat pipes constitute a low-pressure evaporator system. 6. The converter primary pure dry dust removal system integrating full waste heat recovery and stable fine purification according to claim 1 is characterized in that the waste heat recovery system includes a torch waste heat recovery device using an enhanced fin heat exchange tube structure.