阅读说明：本技术 一种高温低氮高效预热节能型环保热风炉 (High-temperature low-nitrogen efficient preheating energy-saving environment-friendly hot blast stove ) 是由 马茜 吕艳玲 刘力铭 刘力源 艾会霞 赵晓璐 于 2021-07-29 设计创作，主要内容包括：本发明提供一种高温低氮高效预热节能型环保热风炉,包括悬链线式拱顶,所述拱顶内部设有燃烧室,所述拱顶下方的炉体上设有基座,所述基座上设有燃烧器,所述燃烧器内部呈环形矩阵设有多个独立的空腔结构的增压预热室,把所述增压预热室依次划分为相交替排列的第一空腔和第二空腔,所述第一空腔上方的第一通道内设有第一耐火球,所述第二空腔上方的第二通道内设有第二耐火球；初始状态时,所述第一空腔底部的第一耐火球和所述第二空腔底部的第二耐火球分别密封住相对应的第一通道和第二通道。在对空气和煤气进行预热后,调节混合气体的压力值,调节燃烧产生火焰的长度,以得到长火焰和短火焰相互配合的燃烧方式,进而降低氮氧化合物的排放。(The invention provides a high-temperature low-nitrogen efficient preheating energy-saving environment-friendly hot blast stove which comprises a catenary type vault, wherein a combustion chamber is arranged in the vault, a base is arranged on a stove body below the vault, a burner is arranged on the base, a plurality of independent pressurizing preheating chambers with cavity structures are arranged in the burner in an annular matrix manner, the pressurizing preheating chambers are sequentially divided into a first cavity and a second cavity which are alternately arranged, a first fire-resistant ball is arranged in a first channel above the first cavity, and a second fire-resistant ball is arranged in a second channel above the second cavity; in an initial state, the first refractory ball at the bottom of the first cavity and the second refractory ball at the bottom of the second cavity seal the corresponding first passage and second passage, respectively. After preheating air and coal gas, adjusting the pressure value of the mixed gas, and adjusting the length of flame generated by combustion to obtain a combustion mode that long flame and short flame are mutually matched, thereby reducing the emission of nitrogen oxides.)

1. The utility model provides an energy-saving environmental protection hot-blast furnace is preheated to high temperature low nitrogen high efficiency which characterized in that: the furnace comprises a catenary type vault, wherein a combustion chamber is arranged in the vault, a base is arranged on a furnace body below the vault, a burner is arranged on the base, a plurality of independent supercharging preheating chambers with cavity structures are arranged in the burner in an annular matrix manner, the supercharging preheating chambers are sequentially divided into a first cavity and a second cavity which are alternately arranged, and the upper parts of the first cavity and the second cavity are communicated with the combustion chamber through a combustion nozzle on the burner; the upper end of the first cavity is communicated with the corresponding combustion nozzle through a first channel, and the lower end of the first cavity is communicated with the first pressurizing and preheating mechanism through a pipeline; the upper end of the second cavity is communicated with the corresponding burner tip through a second channel, and the lower end of the second cavity is communicated with a second pressurizing and preheating mechanism through a pipeline; a first refractory ball is arranged in the first channel above the first cavity, and a second refractory ball is arranged in the second channel above the second cavity; in an initial state, the first refractory ball at the bottom of the first cavity and the second refractory ball at the bottom of the second cavity respectively seal the corresponding first channel and second channel;

the first pressurizing and preheating mechanism comprises a first combustion air preheating chamber and a first gas preheating chamber which are mutually independent, a third refractory ball is arranged in a third channel at the top of the first combustion air preheating chamber, and a fourth refractory ball is arranged in a fourth channel at the top of the first gas preheating chamber; the third refractory ball and the fourth refractory ball both have a mass less than the weight of the first refractory ball; all the first combustion air preheating chambers are communicated with the first air inlet through pipelines; all the first gas preheating chambers are communicated with the first gas inlets through pipelines; in an initial state, the third refractory ball seals the third passage, and the fourth refractory ball seals the fourth passage;

the second pressurizing and preheating mechanism comprises a second combustion-supporting air preheating chamber and a second gas preheating chamber which are mutually independent, a fifth refractory ball is arranged in a fifth channel at the top of the second combustion-supporting air preheating chamber, a sixth refractory ball is arranged in a sixth channel at the top of the second gas preheating chamber, and the mass of the fifth refractory ball and the mass of the sixth refractory ball are both smaller than the weight of the second refractory ball; all the second combustion air preheating chambers are communicated with the second air inlets through pipelines; all the second gas preheating chambers are communicated with the second gas inlets through pipelines; in an initial state, the fifth refractory ball seals the fifth passage, and the sixth refractory ball seals the sixth passage;

a heat storage chamber is arranged in the furnace body below the burner, a heat storage body is arranged in the heat storage chamber, and the heat storage body is arranged on the fire grate; the fire grate is fixed on a rigid base of the furnace body through a plurality of pillars; a cold air chamber is arranged below the heat storage chamber, a cold air inlet is arranged on the cold air chamber, and a hot air outlet is arranged below the arch crown.

2. The high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove as claimed in claim 1, characterized in that: the weight of the first refractory ball is greater than that of the second refractory ball, so that the pressure of the mixed gas in the first cavity for jacking up the first refractory ball is greater than that of the mixed gas in the second cavity for jacking up the second refractory ball, and after the first refractory ball is jacked up, the high-pressure mixed gas in the first cavity is ignited to form long flame; after the second refractory ball is jacked up, the low-pressure mixed gas in the second cavity is ignited to form a short flame, and the long flame and the short flame are mixed and combusted in the combustion chamber.

3. The high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove as claimed in claim 1, characterized in that: the weight of the third refractory ball is greater than the weight of the fifth refractory ball; and the furnace walls corresponding to the third refractory ball and the fifth refractory ball are respectively provided with an access hole communicated with the outside.

4. The high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove as claimed in claim 1, characterized in that: the weight of the fourth refractory ball is greater than the weight of the sixth refractory ball; and the furnace walls corresponding to the fourth refractory ball and the sixth refractory ball are respectively provided with an access hole communicated with the outside.

5. The high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove as claimed in claim 1, characterized in that: the diameter of the first refractory ball is larger than that of the first channel, the lower end of the first channel is funnel-shaped, and the first refractory ball is positioned at the lower part of the first channel; and the furnace wall corresponding to the first refractory ball is provided with an access hole communicated with the outside.

6. The high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove as claimed in claim 1, characterized in that: the diameter of the second refractory ball is larger than that of the second channel, the lower end of the second channel is funnel-shaped, and the second refractory ball is positioned at the lower part of the second channel; and the furnace wall corresponding to the second refractory ball is provided with an access hole communicated with the outside.

7. The high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove as claimed in claim 1, characterized in that: the first pressurizing preheating mechanism and the second pressurizing preheating mechanism are cylindrical cavity structures formed by cutting special-shaped refractory bricks and are annularly arranged on the inner side of the furnace wall at the upper part of the regenerative chamber.

8. The high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove as claimed in claim 1, characterized in that: the burner adopts an annular grid type low-nitrogen ceramic burner.

9. The high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove as claimed in claim 1, characterized in that: the regenerative chamber and the cold air chamber are coaxial and have the same cross section area; and thermal expansion gaps are arranged among the heat accumulators in the heat accumulation chamber.

10. The high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove as claimed in claim 1, characterized in that: the heat accumulator is a refractory ball or a checker brick, and the diameter of the refractory ball is phi 40-80 mm; the checker brick is a cone-hole-shaped checker brick, the diameter of a cone hole of the checker brick is 19 holes or 37 holes with the diameter of phi 15-40 mm, and the checker brick is of a regular hexagon or quincunx honeycomb ceramic structure.

Technical Field

The invention relates to the technical field of hot blast stoves, in particular to a high-temperature low-nitrogen efficient preheating energy-saving environment-friendly hot blast stove.

Background

In the production of blast furnaces, the flue gas of the blast furnace hot blast stove often contains harmful substances of oxynitride, which easily causes pollution to the environment, so that the reduction of oxynitride in the combustion products of the blast furnace hot blast stove is increasingly valued by iron and steel enterprises and iron and steel research institutions. The oxynitride is mainly generated by high-temperature hot air combusted in the hot blast stove, and the technical measure for controlling the generation of the oxynitride is mainly to reduce the temperature of the vault of the hot blast stove on the one hand; however, because the higher temperature of the vault of the hot blast stove is the basic premise of improving the temperature of the air supply of the hot blast stove, the difference between the temperature of the vault of the hot blast stove and the temperature of the air supply must be reduced, namely, the heat exchange efficiency of the hot blast stove is improved, and the distribution state of a flue gas flow field in the hot blast stove is optimized; another aspect is to reduce the excess air factor α.

The existing hot blast stove for reducing the emission of nitrogen oxides is mostly a ceramic burner and a top combustion type hot blast stove in the patent application No. CN111964056A, the low NOx burner matched with the top combustion type hot blast stove divides air gas into a plurality of staggered rotational flows on a horizontal plane for mixing through the change of an internal structure form, or realizes the staggered rotational flow mixing of the air gas in a vertical direction, so that the air gas is mixed more uniformly, the combustion is more sufficient, and the combustion efficiency is improved in the same combustion space. The NOx content in the combustion flue gas can be reduced by adopting a thick-thin combustion technology through the non-stoichiometric proportion of local air gas so as to meet the requirements of national environmental protection and hot blast stove technical development; and the emission of NOx in combustion flue gas is reduced, the stress corrosion of a furnace shell in a high-temperature area and the dew point corrosion of a low-temperature section of a heat exchanger can be reduced, and therefore the service lives of the hot blast stove and equipment thereof are prolonged.

However, the existing similar low-oxynitride discharging hot blast stove and the corresponding burner lack preheating of combustion air and coal gas in the use process, so that higher combustion temperature cannot be obtained, and the heat energy utilization rate is to be further improved; meanwhile, the proportion of the supplied combustion air and the supplied coal gas is inconvenient to control, so that the discharge amount of nitrogen oxides in the combustion process is difficult to control.

Therefore, in view of the above, research and improvement are made on the structure of the existing hot blast stove, and a high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove is provided, so as to achieve the purposes of preheating combustion air and coal gas, improving the combustion temperature and the heat energy utilization rate, controlling the proportion of the combustion air and the coal gas, and reducing the discharge amount of nitrogen oxides.

Disclosure of Invention

In order to solve the technical problems, the invention provides a high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove, which aims to solve the problems that the conventional hot blast stove is lack of preheating combustion air and coal gas, cannot obtain higher combustion temperature and needs to be further improved in heat energy utilization rate; meanwhile, the proportion of the supplied combustion air and the supplied coal gas is inconvenient to control, so that the discharge amount of nitrogen oxides in the combustion process is difficult to control.

The method is achieved by the following specific technical means: a high-temperature low-nitrogen efficient preheating energy-saving environment-friendly hot blast stove comprises a catenary type vault, wherein a combustion chamber is arranged inside the vault, a base is arranged on a stove body below the vault, a burner is arranged on the base, a plurality of independent supercharging preheating chambers with cavity structures are arranged in the burner in an annular matrix manner, the supercharging preheating chambers are sequentially divided into a first cavity and a second cavity which are alternately arranged, and the upper parts of the first cavity and the second cavity are communicated with the combustion chamber through a combustion nozzle on the burner; the upper end of the first cavity is communicated with the corresponding combustion nozzle through a first channel, and the lower end of the first cavity is communicated with the first pressurizing and preheating mechanism through a pipeline; the upper end of the second cavity is communicated with the corresponding burner tip through a second channel, and the lower end of the second cavity is communicated with a second pressurizing and preheating mechanism through a pipeline; a first refractory ball is arranged in the first channel above the first cavity, and a second refractory ball is arranged in the second channel above the second cavity; in an initial state, the first refractory ball at the bottom of the first cavity and the second refractory ball at the bottom of the second cavity respectively seal the corresponding first channel and second channel;

the first pressurizing and preheating mechanism comprises a first combustion air preheating chamber and a first gas preheating chamber which are mutually independent, a third refractory ball is arranged in a third channel at the top of the first combustion air preheating chamber, and a fourth refractory ball is arranged in a fourth channel at the top of the first gas preheating chamber; the third refractory ball and the fourth refractory ball both have a mass less than the weight of the first refractory ball; all the first combustion air preheating chambers are communicated with the first air inlet through pipelines; all the first gas preheating chambers are communicated with the first gas inlets through pipelines; in an initial state, the third refractory ball seals the third passage, and the fourth refractory ball seals the fourth passage;

the second pressurizing and preheating mechanism comprises a second combustion-supporting air preheating chamber and a second coal gas preheating chamber which are mutually independent, a fifth refractory ball is arranged in a fifth channel at the top of the second combustion-supporting air preheating chamber, a sixth refractory ball is arranged in a sixth channel at the top of the second coal gas preheating chamber, and the mass of the fifth refractory ball and the mass of the sixth refractory ball are both smaller than the weight of the second refractory ball; all the second combustion air preheating chambers are communicated with the second air inlets through pipelines; all the second gas preheating chambers are communicated with the second gas inlets through pipelines; in an initial state, the fifth refractory ball seals the fifth passage, and the sixth refractory ball seals the sixth passage;

a heat storage chamber is arranged in the furnace body below the burner, a heat storage body is arranged in the heat storage chamber, and the heat storage body is arranged on the fire grate; the fire grate is fixed on a rigid base of the furnace body through a plurality of pillars; a cold air chamber is arranged below the heat storage chamber, an inlet is arranged on the cold air chamber, and a hot air outlet is arranged below the arch crown.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention adopts the catenary type vault, the ratio of the height of the catenary type vault to the diameter of the cross section is set to be more than 1.1, and the ratio is matched with the annular grid type low-nitrogen ceramic burner in the device, so that the hot blast stove adopting the catenary type vault can obtain ideal theoretical combustion temperature in the vault on one hand, and the uniform degree of airflow distribution on the cross section of the regenerator is greatly improved on the other hand, thereby optimizing the performance of the hot blast stove.

2. The invention is provided with a plurality of independent pressurizing and preheating chambers with cavity structures, and on one hand, the pressurizing and preheating chambers are used for carrying out secondary mixing on the combustion-supporting air and the coal gas after primary mixing so as to enable the combustion to be more sufficient; on the other hand, the mixed gas entering the pressurizing preheating chamber can be rapidly secondarily preheated by high-temperature flue gas descending after being combusted in the combustion chamber, and the mixed gas secondarily preheated in the pressurizing preheating chamber is converted into high-temperature mixed gas which can obviously improve the combustion temperature of coal gas when entering the combustion chamber for combustion; moreover, the mixed gas entering the pressurizing preheating chamber can be pressurized for the second time, a high-pressure mixed gas spraying effect is generated when the mixed gas enters the combustion chamber, the length of flame generated by combustion after spraying is adjusted by adjusting the pressure value of the mixed gas, so that a combustion mode that long flame and short flame are matched with each other is obtained, and conditions are created for reducing the generation of nitrogen oxides; the high-pressure gas mixture that sprays simultaneously can not only aggravate the interior vortex effect of burning gas mixture of vault to promote the combustion effect in the combustion chamber, high-pressure gas mixture is when impacting on the vault and turn over the downstream in addition, and the high temperature flue gas after the drive burning that can be better moves to the heat accumulation indoor downwards fast, and then improves the heat exchange rate of heat accumulator in the heat accumulation chamber. Therefore, on one hand, the combustion temperature of the coal gas in the stove is improved, on the other hand, the heat exchange efficiency in the stove is improved, and the hot blast stove is enabled to provide high hot blast performance.

3. According to the invention, the weight of the first refractory ball is greater than that of the second refractory ball, so that the pressure of the mixed gas in the first cavity for jacking up the first refractory ball is greater than that of the mixed gas in the second cavity for jacking up the second refractory ball, and the high-pressure mixed gas in the first cavity is ignited to form long flame; after the second fire-resistant ball is jacked up, the low-pressure mixed gas in the second cavity is ignited to form short flame, the long flame and the short flame are mixed and combusted in the combustion chamber, and the long flame and the short flame are matched with each other in a combustion mode, so that the generation amount of nitrogen oxides can be reduced when the mixed gas is combusted; the first refractory ball can be periodically lifted and lowered by controlling the weight of the first refractory ball and the amount of mixed gas filled into the first cavity, so that the first channel is periodically opened and closed; the high-pressure mixed gas which is periodically sprayed and combusted can reduce the ultrahigh combustion temperature in the vault in the spraying and combusting clearance while improving the combustion temperature in the vault, prevent the ultrahigh combustion temperature from being formed in the vault, and prevent excessive oxynitride from being generated in the vault in the combustion process, and control the generation amount of the oxynitride within the required standard range, so that the hot-blast stove becomes an energy-saving and environment-friendly hot-blast stove.

4. According to the invention, the third refractory ball is periodically raised and lowered by selecting and controlling the weight of the third refractory ball, so that high-temperature high-pressure air in the first combustion-supporting air preheating chamber periodically enters the first cavity through the third channel to form pulsating high-temperature high-pressure combustion-supporting air; similarly, the weight of the fourth refractory ball is selected and controlled, so that the high-temperature high-pressure gas in the first gas preheating chamber periodically enters the first cavity through the fourth channel to form pulsating high-temperature high-pressure gas; when the pulsating high-temperature high-pressure combustion-supporting air and the pulsating high-temperature high-pressure coal gas enter the first cavity, a better mixing effect can be generated, the subsequent sufficient combustion is more facilitated, and the generation amount of oxynitride is effectively controlled; meanwhile, the proportion of the amount of the combustion-supporting air to the amount of the coal gas can be effectively adjusted by controlling the weights of the third refractory ball and the fourth refractory ball and controlling the pressure of the combustion-supporting air and the pressure of the coal gas, so that the combustion can be carried out in an anoxic combustion or an oxygen-enriched combustion at different stages, and the emission of oxynitride can be effectively controlled.

5. According to the invention, the ratio of combustion-supporting air and coal gas entering the first cavity is adjusted by adjusting the weight ratio of the third refractory ball and the fourth refractory ball, so that the coefficient alpha of the excess combustion-supporting air is controlled; similarly, the weight ratio of the fifth refractory ball to the sixth refractory ball is adjusted, so that the ratio of combustion-supporting air and coal gas entering the second cavity is adjusted, and the coefficient alpha of the excess combustion-supporting air is controlled; through the adjusting mode, the coefficient alpha of the excess combustion air in the first cavity and the second cavity is controlled to approach 1, so that the combustion temperature in the combustion chamber 2 approaches the maximum theoretical combustion temperature, the heat exchange rate can be effectively improved, and the emission of nitrogen oxides is reduced.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Drawings

Fig. 1 is a schematic sectional structure diagram of the hot blast stove of the present invention.

Fig. 2 is a schematic view of the burner structure of the present invention.

Fig. 3 is a schematic perspective sectional view of the first cavity and the first pressurized preheating mechanism according to the present invention.

Fig. 4 is a schematic plan view of the first cavity and the first pressurized preheating mechanism of the present invention.

Fig. 5 is a schematic perspective sectional view of a second cavity and a second pressurized preheating mechanism according to the present invention.

Fig. 6 is a schematic plan view of the second cavity and the second pressurized preheating mechanism of the present invention.

FIG. 7 is an enlarged view of a portion of the invention shown at A in FIG. 3.

Fig. 8 is a partial enlarged view of the invention at B in fig. 3.

In the drawings, the corresponding relationship between the component names and the reference numbers is as follows:

1. a catenary dome; 2. a combustion chamber; 3. a base; 4. a burner; 5. a pressurized preheating chamber; 501. a first cavity; 502. a second cavity; 503. a first refractory ball; 504. a second refractory ball; 505. a first channel; 506. a second channel; 6. a combustion nozzle; 7. a first pressurizing and preheating mechanism; 701. a first combustion air preheating chamber; 702. a first gas preheating chamber; 703. a third refractory ball; a fourth refractory ball; 705. a third channel; 706. a first air inlet; 707. a fourth channel; 708. a first gas inlet; 8. a second pressurizing and preheating mechanism; 801. a second combustion air preheating chamber; 802. a second gas preheating chamber; 803. a fifth refractory ball; 804. a sixth refractory ball; 805. a fifth channel; 806. a second air inlet; 807. a sixth channel; 808. a second gas inlet; 9, a regenerative chamber; 10. a heat accumulator; 11. a grate; 12. a cold air chamber; 13. a hot air outlet; 14. and a cold air inlet.

Detailed Description

The embodiments of the present invention will be described in further detail with reference to the drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

In the description of the present invention, "a plurality" means two or more unless otherwise specified; the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", "head", "tail", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "connected" and "connected" are to be interpreted broadly, e.g., as being fixed or detachable or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example (b):

as shown in figures 1 to 8:

the invention provides a high-temperature low-nitrogen high-efficiency preheating energy-saving environment-friendly hot blast stove, which comprises a catenary type vault 1; the air supply temperature of the hot blast stove is an important parameter for measuring the technical index of the hot blast stove, when the performance of the hot blast stove is optimized, on one hand, the theoretical combustion temperature of coal gas in the hot blast stove is improved, and the adopted measure is to improve the temperature of the vault of the hot blast stove, so the structural design of the vault has a decisive effect on improving the combustion temperature in the hot blast stove; based on the reasons, the invention adopts the catenary type vault, the ratio of the height of the catenary type vault 1 to the diameter of the cross section is set to be more than 1.1, and the ratio is matched with the annular grid type low-nitrogen ceramic burner in the device, so that the hot blast stove adopting the catenary type vault 1 can obtain ideal theoretical combustion temperature in the vault 1 on one hand, and the air flow distribution uniformity degree on the cross section of the regenerative chamber 9 is greatly improved on the other hand.

At the same time, to obtain a higher dome temperature, preheating of the combustion air and the gas is required. According to production experience, when the temperature of both air and fuel gas is heated to 400 ℃, the theoretical combustion temperature can be increased by about 200 ℃ and can reach 1580 ℃ compared with the condition that the temperature of both air and fuel gas is 25 ℃. In order to better preheat the combustion air and the coal gas, the internal structure of the existing hot blast stove is further optimized in the following way. Specifically, as shown in fig. 1-8: the combustor is characterized in that a combustion chamber 2 is arranged inside the vault 1, a base 3 is arranged on the furnace body below the vault 1, a combustor 4 is arranged on the base 3, and the combustor 4 adopts an annular grid type low-nitrogen ceramic combustor to improve the combustion effect and reduce the generation of nitrogen oxides. A plurality of independent pressurizing and preheating chambers 5 with cavity structures are arranged in the combustor 4 in an annular matrix manner, and on one hand, the pressurizing and preheating chambers 5 are used for carrying out secondary mixing on the combustion-supporting air and the coal gas which are subjected to primary mixing, so that the combustion-supporting air and the coal gas are better mixed, and the combustion is more sufficient; on the other hand, the mixed gas entering the pressurized preheating chamber 5 can be rapidly secondarily preheated by high-temperature flue gas descending after being combusted in the combustion chamber 2, the pressurized preheating chamber 5 is secondarily preheated into high-temperature mixed gas, and when the mixed gas enters the combustion chamber 2 for combustion, the combustion temperature of coal gas can be obviously improved, so that conditions are created for realizing high air temperature; moreover, the mixed gas entering the pressurizing and preheating chamber 5 can be pressurized for the second time, when the mixed gas enters the combustion chamber 2, the high-pressure mixed gas injection effect is generated, the length of flame generated by combustion after injection is adjusted by adjusting the pressure value of the mixed gas, so that a combustion mode that long flame and short flame are matched with each other is obtained, and conditions are created for reducing the generation of nitrogen oxides; the high-pressure gas mixture that sprays simultaneously can not only aggravate the vortex effect of burning gas mixture in the vault 1 to promote the combustion effect in the combustion chamber 2, high-pressure gas mixture is when impacting on the vault 1 and turn over the downstream in addition, and the high temperature flue gas after the drive burning that can be better moves to regenerator 9 in to the downward rapid motion, and then improves regenerator 10's in regenerator 9 heat exchange rate. So, through the design of pressure boost preheating chamber 5, improve the combustion temperature of stove coal gas on the one hand, on the other hand has improved the heat exchange efficiency in the stove, has realized that the hot-blast furnace provides high hot-blast performance.

In order to preheat mixed gas with different pressures in the pressurized preheating chamber 5 and obtain long flame and short flame to form long-short flame mixing when the mixed gas is combusted, the cavity structure 5 is sequentially divided into a first cavity 501 and a second cavity 502 which are alternately arranged, and the first cavity 501 and the second cavity 502 are used for mixing combustion air and coal gas with different pressures so as to obtain mixed gas with different pressures; specifically, the upper parts of the first cavity 501 and the second cavity 502 are communicated with the combustion chamber 2 through a combustion nozzle 6 on the combustor 4, so that the fuel gas in the first cavity 501 and the second cavity 502 is injected into the combustion chamber 2 through the combustion nozzle 6 for sufficient combustion; the first cavity 501 and the second cavity 502 are stacked by adopting refractory checker bricks to form a sealed cavity structure, and are not directly communicated with the interior of the furnace body so as to ensure the sufficient mixing and pressurization of the gases in the two cavities; simultaneously, the checker bricks for piling up the first cavity 501 and the second cavity 502 can be heated in the descending process of the high-temperature flue gas, so that the mixed gas in the first cavity 501 and the second cavity 502 can be preheated for the second time, and the mixed gas preheated for the second time in the first cavity 501 and the second cavity 502 can obtain higher combustion temperature during combustion.

In the present invention, the first cavity 501 is used to provide a high-pressure mixture of combustion air and gas to form a long flame; the second cavity 502 is used for providing low-pressure combustion air and gas mixture of coal gas to form a short flame for combustion, so that the long flame and the short flame are mixed, the combustion temperature is increased, and the generation of nitrogen oxides is reduced.

The upper end of the first cavity 501 is communicated with the corresponding combustion nozzle 6 through a first channel 505, so that the high-pressure mixed gas is sprayed into the combustion chamber 2 through the combustion nozzle 6 for combustion; the lower end of the first cavity 501 is communicated with a first pressurizing and preheating mechanism 7 through a pipeline, and the first pressurizing and preheating mechanism 7 is used for carrying out primary pressurization and primary preheating on combustion air; the upper end of the second cavity 502 is communicated with a corresponding burner nozzle through a second channel 506, so that low-pressure mixed gas is sprayed into the combustion chamber 2 through the combustion nozzle 6 for combustion; the lower end of the second cavity 502 is communicated with a second pressurizing preheating mechanism 8 through a pipeline, and the second pressurizing preheating mechanism 8 is used for pressurizing and preheating coal gas for one time.

A first refractory ball 503 is disposed in a first passage 505 above the first cavity 501, and a second refractory ball 504 is disposed in a second passage 506 above the second cavity 502; in the initial state, a first refractory ball 503 at the bottom of the first cavity 501 and a second refractory ball 504 at the bottom of the second cavity 501 seal a corresponding first passage 505 and a corresponding second passage 506, respectively; wherein, the weight of the first refractory ball 503 is greater than that of the second refractory ball 504, so that the pressure of the mixed gas in the first cavity 501 for jacking up the first refractory ball 503 is greater than that of the mixed gas in the second cavity 502 for jacking up the second refractory ball 504, and after the first refractory ball 503 is jacked up, the high-pressure mixed gas in the first cavity 501 is ignited to form long flame; after the second fire-resistant ball 504 is jacked up, the low-pressure mixed gas in the second cavity 502 is ignited to form short flame, the long flame and the short flame are mixed and combusted in the combustion chamber 2, and the generation amount of nitrogen oxides can be reduced when the mixed gas is combusted due to the combustion mode of mutual cooperation of the long flame and the short flame; simultaneously from the high-pressure mist of ejection in the first cavity 501, can not only aggravate the vortex effect of burning mist in the vault 1 to promote the combustion effect in the combustion chamber 2, high-pressure mist is when assaulting on the vault 1 and turning over the downward motion, can drive the high temperature flue gas after the burning downward rapid movement to regenerator 9 in, and then improve regenerator 10's in the regenerator 9 heat exchange rate. By controlling the weight of the second refractory ball 504 and the amount of the mixed gas charged into the second cavity 502, the second refractory ball 504 can be continuously jacked up, so that low-pressure mixed gas can be continuously ejected through the second cavity 502, and the low-pressure mixed gas can be continuously combusted, so that the vault 1 can be kept at a higher combustion temperature; by controlling the weight of the first refractory ball 503 and the amount of the mixture gas filled into the first cavity 501, the first refractory ball 501 can be raised and lowered periodically, so that the first passage 505 is opened and closed periodically; when the first channel 505 is periodically opened, the high-pressure mixed gas in the first cavity 501 is sprayed into the combustion chamber 2 through the second channel and the corresponding combustion nozzle 6, and the high-pressure mixed gas which is periodically sprayed and combusted can be sprayed and combusted in the gap while the combustion temperature in the vault 1 is increased, so that the ultrahigh combustion temperature in the vault 1 is reduced, and the ultrahigh combustion temperature in the vault 1 is prevented from being formed, so that excessive oxynitride is generated in the vault 1 in the combustion process; according to data obtained from production experience, the excessive dome temperature can increase the generation of oxynitride during internal combustion, and the higher the dome temperature is, the higher the generation amount of oxynitride is; therefore, the high-pressure mixed gas is periodically injected into the vault 1 and combusted, so that the vault 1 can obtain a high ideal combustion temperature, the temperature in the vault 1 can be effectively controlled, the combustion temperature is prevented from being overhigh, the generation amount of oxynitride is prevented from being increased, and the generation amount of oxynitride is controlled within a required standard range. Meanwhile, when high-pressure mixed gas which is periodically sprayed and combusted impacts the arch crown 1 and is reversely folded to move downwards, high-temperature flue gas after combustion can be driven to rapidly move downwards into the heat storage chamber 9, the heat exchange rate of a heat accumulator 10 in the heat storage chamber 9 is further increased, the temperature of hot air can be further increased, and the overall performance of the hot blast stove is optimized.

Specifically, the diameter of the first refractory ball 503 is larger than that of the first passage 505, and the lower end of the first passage 505 is funnel-shaped; in the initial state, the first refractory ball 503 is located below the first passage 505 and forms a seal with the first passage 505; after the mixed gas with a certain pressure is introduced, the mixed gas with the pressure can jack up the first refractory ball 503, so that the first channel 505 is opened, and the mixed gas injected at a high pressure is finally injected into the combustion chamber 2 for combustion; an access hole communicated with the outside is formed in the furnace wall corresponding to the first refractory ball 503, so that the first refractory ball 503 can be conveniently replaced when broken or damaged after being used for a long time; on the other hand, the first refractory balls 503 with different mass can be replaced according to different production conditions to obtain mixed gas with different injection pressures, and correspondingly obtain corresponding combustion temperature and heat exchange efficiency.

Specifically, the diameter of the second refractory ball 504 is larger than that of the second channel 506, and the lower end of the second channel 506 is funnel-shaped; in the initial state, the second refractory ball 504 is located below the second channel 506 and is capable of forming a seal with the second channel 506; and the furnace wall corresponding to the second refractory ball 504 is provided with an access hole communicated with the outside. After the mixed gas with a certain pressure is introduced, the mixed gas with the pressure can jack up the second refractory ball 504, so that the second channel 506 is opened, and the mixed gas injected at a relatively high pressure is finally injected into the combustion chamber 2 for combustion; the furnace wall corresponding to the second refractory ball 504 is provided with an access hole communicated with the outside, so that on one hand, the access hole is convenient for the second refractory ball 504 to be replaced when the second refractory ball is broken or damaged after being used for a long time; on the other hand, the second refractory balls 504 of different masses can be replaced according to different production conditions, so as to obtain mixed gases of different injection pressures and correspondingly obtain corresponding combustion temperatures and heat exchange efficiencies.

As shown in fig. 3-4, the first pressurized preheating mechanism 7 includes a first combustion air preheating chamber 701 and a first gas preheating chamber 702 which are independent of each other, and the first combustion air preheating chamber 701 performs primary preheating and primary pressurization on combustion air which subsequently enters the first cavity 501; the first gas preheating chamber 702 performs primary preheating and primary pressurization on the gas subsequently entering the first cavity 501

Specifically, a third fire-resistant ball 703 is arranged in a third channel 705 at the top of the first combustion air preheating chamber 701, and in an initial state, the third fire-resistant ball 703 seals the third channel 705; after external combustion-supporting air enters the first combustion-supporting air preheating chamber 701, the third channel 705 is sealed under the action of the gravity of the third refractory ball 703, and the combustion-supporting air entering the first combustion-supporting air preheating chamber 701 gradually forms high-pressure combustion-supporting air; meanwhile, when high-temperature flue gas entering the regenerator 9 from the vault 1 passes through the first combustion air chamber preheating chamber 701, the combustion air in the regenerator is preheated for the first time, so that the subsequent combustion temperature is increased; similarly, a fourth refractory ball 704 is arranged in a fourth channel 707 at the top of the first gas preheating chamber 702; in the initial state, the fourth refractory ball 704 seals the fourth passage 707; after the external gas enters the first gas preheating chamber 702, the fourth passage 707 is sealed due to the gravity of the fourth refractory ball 704, and the gas entering the first gas preheating chamber 702 gradually forms high-pressure gas; meanwhile, when high-temperature flue gas entering the regenerator 9 from the vault 1 passes through the first gas preheating chamber 702, the gas in the regenerator is preheated for the first time, so that the subsequent combustion temperature is increased; meanwhile, through selection and control of the weight of the third refractory ball 703, the third refractory ball 703 is jacked up by the high-pressure air charged into the first combustion-supporting air preheating chamber 701, the high-pressure combustion-supporting air in the first combustion-supporting air preheating chamber 701 jacks up the third refractory ball 703 and enters the first cavity 501 through the third channel 705, and then the third refractory ball 703 falls down due to the reduction of the pressure in the first combustion-supporting air preheating chamber 701 to form a seal for the third channel 705; similarly, the weight of the fourth refractory ball 704 is selected and controlled, so that the high-temperature high-pressure gas in the first gas preheating chamber 702 periodically enters the first cavity 501 through the fourth channel 707, and a pulsating high-temperature high-pressure gas is formed; when the pulsating high-temperature high-pressure combustion air and the pulsating high-temperature high-pressure coal gas enter the first cavity 501, a better mixing effect can be generated, the subsequent sufficient combustion is more facilitated, and the generation amount of oxynitride is effectively controlled; meanwhile, by controlling the weights of the third refractory ball 703 and the fourth refractory ball 704 and the pressure of the combustion air and the coal gas, the proportion of the amount of the combustion air and the amount of the coal gas can be effectively adjusted, so that the combustion can be performed in different stages by oxygen-deficient combustion or oxygen-enriched combustion, and the emission of nitrogen oxides can be effectively controlled.

Specifically, the mass of the third refractory ball 703 and the mass of the fourth refractory ball 704 are both smaller than the weight of the first refractory ball 503, so as to ensure that the high-temperature high-pressure combustion-supporting air and/or the high-temperature high-pressure coal gas entering the first cavity 501 cannot directly jack up the first refractory ball 503 and enter the combustion chamber 2 for combustion after the third refractory ball 703 is jacked up and/or the fourth refractory ball 704 is jacked up; therefore, the high-temperature high-pressure combustion air and the high-temperature high-pressure coal gas can be fully mixed in the first cavity 501, secondary pressurization is carried out, and meanwhile, high-temperature flue gas entering the regenerator 9 is heated secondarily, so that preparation is made for high-temperature combustion. All the first combustion air preheating chambers 701 are communicated with the first air inlets 706 through pipes to supply combustion air to all the first combustion air preheating chambers 701 through the first air inlets 706; all of the first gas preheating compartments 702 are in communication with the first gas inlet 708 through piping to supply gas into the first gas preheating compartments 702 through the first gas inlet 708.

As shown in fig. 5-6, the second pressurized preheating mechanism 8 includes a second combustion air preheating chamber 801 and a second gas preheating chamber 802 which are independent from each other, and the second combustion air preheating chamber 801 performs primary preheating and primary pressurization on the combustion air which subsequently enters the second cavity 502; the second gas preheating chamber 802 performs primary preheating and primary pressurization on the gas subsequently entering the second cavity 502; a fifth refractory ball 803 is arranged in a fifth channel 805 at the top of the second combustion air preheating chamber 801; in an initial state, the fifth passage 805 is sealed by the fifth refractory ball 803, after external combustion air enters the second combustion air preheating chamber 801, the fifth passage 805 is sealed due to the gravity action of the fifth refractory ball 803, and the combustion air entering the second combustion air preheating chamber 801 gradually forms high-pressure combustion air; meanwhile, when high-temperature flue gas entering the regenerator 9 from the vault 1 passes through the second combustion air chamber preheating chamber 801, the combustion air in the regenerator is preheated for the first time, so that the subsequent combustion temperature is increased; similarly, a sixth refractory ball 804 is arranged in a sixth channel 807 at the top of the second gas preheating chamber 802; in the initial state, sixth refractory ball 804 seals sixth passage 807; after the external gas enters the second gas preheating chamber 802, the sixth passage 807 is sealed due to the gravity action of the sixth refractory ball 804, and the gas entering the second gas preheating chamber 802 gradually forms high-pressure gas; meanwhile, when high-temperature flue gas entering the regenerator 9 from the vault 1 passes through the second gas preheating chamber 802, the gas in the regenerator is preheated for the first time, so that the subsequent combustion temperature is increased; meanwhile, through the selection and control of the weight of the fifth refractory ball 803, the fifth refractory ball 803 is jacked up by the high-pressure air filled in the second combustion-supporting air preheating chamber 801, the high-pressure combustion-supporting air in the second combustion-supporting air preheating chamber 801 jacks up the fifth refractory ball 803 and enters the second cavity 502 through the fifth passage 805, then the fifth refractory ball 803 falls down due to the reduction of the pressure in the second combustion-supporting air preheating chamber 801, the fifth passage 805 is sealed again, and the operation is repeated, so that the fifth refractory ball 803 periodically rises and falls, the high-temperature high-pressure air in the second combustion-supporting air preheating chamber 801 can periodically enter the second cavity 502 through the fifth passage 805 to form pulsating high-temperature high-pressure combustion-supporting air; similarly, the weight of the sixth refractory ball 804 is selected and controlled, so that the high-temperature high-pressure gas in the second gas preheating chamber 802 periodically enters the second cavity 502 through the sixth passage 807 to form pulsating high-temperature high-pressure gas; when the pulsating high-temperature high-pressure combustion-supporting air and the pulsating high-temperature high-pressure coal gas enter the second cavity 502, a better mixing effect can be generated, the subsequent sufficient combustion is more facilitated, and the generation amount of oxynitride is effectively controlled; meanwhile, by controlling the weight of the fifth refractory ball 803 and the sixth refractory ball 804 and the pressure of the combustion air and the coal gas, the proportion of the amount of the combustion air and the amount of the coal gas can be effectively adjusted, so that the combustion can be performed in different stages by oxygen-poor combustion or oxygen-rich combustion, and the emission of nitrogen oxides can be effectively controlled.

The mass of the fifth refractory ball 803 and the sixth refractory ball 804 is less than the weight of the second refractory ball 504, so as to ensure that the high-temperature high-pressure combustion-supporting air and/or the high-temperature high-pressure coal gas entering the second cavity 502 directly jack the second refractory ball 504 and enter the combustion chamber 2 for combustion after the fifth refractory ball 803 is jacked up and/or the sixth refractory ball 804 is jacked up; therefore, the high-temperature high-pressure combustion air and the high-temperature high-pressure coal gas can be fully mixed in the second cavity 502, secondary pressurization is carried out, and meanwhile, high-temperature flue gas entering the regenerator 9 is heated secondarily, so that preparation is made for high-temperature combustion. All the second combustion air preheating chambers 801 are communicated with the second air inlets 806 through pipes to supply the combustion air to all the second combustion air preheating chambers 801 through the second air inlets 806; all of the second gas preheating compartments 802 are in communication with the second gas inlet 808 through a conduit to provide gas into the second gas preheating compartments 802 through the second gas inlet 808.

In order to ensure that the mixed gas with higher pressure and higher temperature in the first cavity 501 can be obtained faster and better than those in the second cavity 502, the weight of the third refractory ball 703 is greater than that of the fifth refractory ball 803 through selection and control, so that the time for staying in the first combustion air preheating chamber 701 is longer, and further the combustion air in the first combustion air preheating chamber 701 can obtain higher primary supercharging pressure and primary preheating temperature than the combustion air in the second combustion air preheating chamber 801; similarly, the weight of the fourth refractory ball 704 is greater than that of the sixth refractory ball 804, so that the gas stays in the first gas preheating chamber 702 for a longer time, and further the gas in the first gas preheating chamber 702 can obtain higher primary pressurization pressure and primary preheating temperature than the gas in the second gas preheating chamber 802; correspondingly, after the combustion air and the coal gas which are subjected to primary pressurization and primary preheating enter the first cavity 501 and are fully mixed, after the combustion air and the coal gas which are subjected to primary pressurization and primary preheating enter the second cavity 502 and are fully mixed, the initial pressure and the initial temperature of the mixed gas in the first cavity 501 are higher than those of the mixed gas in the second cavity 502, and then long flames are generated for the combustion of the mixed gas in the first cavity 501, short flames are generated for the combustion of the mixed gas in the second cavity 502, and finally long and short flame mixed combustion is formed, so that conditions for reducing the emission of nitrogen oxides are created.

Specifically, the furnace walls corresponding to the third refractory ball 703 and the fifth refractory ball 803 are respectively provided with an access hole communicated with the outside; on one hand, the access hole is convenient for replacing the third refractory ball 703 and the fifth refractory ball 803 when the third refractory ball is broken or damaged after long-term use; on the other hand, the third refractory ball 703 with different mass and the fifth refractory ball 803 with different mass can be replaced according to different production conditions to obtain combustion air and gas with different injection pressures, and correspondingly obtain corresponding combustion temperature and heat exchange efficiency.

Specifically, the furnace walls corresponding to the fourth refractory ball 704 and the sixth refractory ball 804 are respectively provided with an access hole communicated with the outside; on one hand, the access hole facilitates the replacement of the fourth refractory ball 704 and the sixth refractory ball 804 when the fourth refractory ball is broken or damaged after long-term use; on the other hand, the fourth refractory balls 704 of different mass and the sixth refractory balls 804 of different mass can be replaced according to different production conditions, so as to obtain combustion air and gas of different injection pressures and correspondingly obtain corresponding combustion temperatures and heat exchange efficiencies.

In order to further improve the combustion temperature in the vault 1, improve the heat exchange efficiency and reduce the discharge amount of nitrogen oxides, the weight ratio of the third fire-resistant ball 703 and the fourth fire-resistant ball 704 is adjusted according to the experience accumulated in the actual production, so that the ratio of combustion-supporting air and coal gas entering the first cavity 501 is adjusted, and further the coefficient alpha of excess combustion-supporting air is controlled; similarly, the weight ratio of the fifth refractory ball 803 to the sixth refractory ball 804 is adjusted, so as to adjust the ratio of the combustion air and the coal gas entering the second cavity 502, and further control the coefficient alpha of the excess combustion air; by the above adjustment method, the excess combustion air coefficient α in the first cavity 501 and the second cavity 502 is controlled to approach 1, so that the combustion temperature in the combustion chamber 2 approaches the maximum theoretical combustion temperature, and finally the heat exchange rate can be effectively improved, and the emission of nitrogen oxides can be reduced.

A heat storage chamber 9 is arranged in the furnace body below the burner 4, a heat storage body 10 is arranged in the heat storage chamber 9, and the heat storage body 10 is arranged on the fire grate 11; three sections of checker bricks which are made of different materials and have heat transfer holes with equal sections and coaxial butt joint and communicated with each other and high-utilization-rate and high-efficiency heat storage are arranged in the heat storage chamber 9, the structure of the checker bricks is a horizontal airflow channel and a longitudinal airflow channel which are connected in a horizontal mode through air, non-uniform flue gas and cold air flow fields are automatically adjusted under the action of certain differential pressure and differential resistance, and the purpose of high-efficiency heat storage and heat exchange is achieved. The fire grate 11 is fixed on the rigid base of the furnace body through a plurality of pillars; a cold air chamber 12 is arranged below the heat storage chamber 9, a cold air inlet 14 is arranged on the cold air chamber 12, and a hot air outlet 13 is arranged below the arch crown 1.

The first supercharging preheating mechanism and the second supercharging preheating mechanism are cylindrical cavity structures formed by cutting special-shaped refractory bricks and are annularly arranged on the inner side of the furnace wall at the upper part of the regenerator 9, and in the process that high-temperature flue gas in the vault 1 downwards enters the regenerator 9, the first supercharging preheating mechanism and the second supercharging preheating mechanism can be heated through the special-shaped refractory bricks, so that combustion-supporting air and coal gas in the first supercharging preheating mechanism and the second supercharging preheating mechanism are preheated for one time, and conditions are created for subsequently improving the combustion temperature.

The regenerative chamber 9 and the cold air chamber 12 are coaxial and have the same cross section area; thermal expansion gaps are arranged among the heat accumulators 10 in the heat accumulation chamber 9; after the high-temperature flue gas in the vault 1 flows downwards into the heat storage chamber 9, the heat of the high-temperature flue gas heats the heat storage body 10 for energy storage. The heat accumulator 10 is a refractory ball or a checker brick, and the diameter of the refractory ball is phi 40-80 mm; the checker brick is a tapered-hole checker brick, the diameter of a tapered hole of the checker brick is nineteen holes or thirty-seven holes with the diameter of phi 15-40 mm, and the checker brick is of a regular hexagon or quincunx honeycomb ceramic structure. When the nineteen-hole checker brick is adopted, the bottom of one plane of the nineteen-hole checker brick is designed with a communication groove with fifteen millimeters deep connecting check holes, and the check bricks are communicated with each other through the communication structure of the checker brick, so that the checker brick can automatically regulate the uniform distribution of a flue gas flow field and a cold gas flow field depending on pressure and flow speed, when the gas flow passes through the nineteenth hole of the checker brick, namely the central hole, the gas flow can be uniformly regulated in eighteenth groove areas communicated under the action of flowing resistance and pressure to be amplified to the whole regenerator 9 to form a planar state of a pressure-equalizing and flow-equalizing bed which is interconnected and communicated, the distribution states of the flue gas flow field and the cold gas flow field of the regenerator are optimized, the heat exchange efficiency of the hot blast stove is improved, the difference between the vault temperature and the blast temperature of the hot blast stove is reduced, the defect that the staggered check brick holes affect the flow passing through is solved, the key function of improving the blast temperature of the hot blast stove and reducing the emission of nitrogen oxides is played, so that the hot blast stove becomes an energy-saving environment-friendly hot blast stove.

The embodiments of the present invention have been presented for purposes of illustration and description, and are not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.