Industrial gas heating system and method

Abstract

The present invention discloses an industrial gas heating system and method, which includes a gas heating furnace, a heat carrier heating furnace, a first conveying inclined pipe and a second conveying inclined pipe. The gas heating furnace includes a settler and a riser, the upper part of the riser passes through the bottom of the settler and is arranged inside the settler, the first conveying inclined pipe connects the bottom of the heat carrier heating furnace and the lower part of the riser, and the second conveying inclined pipe connects the bottom of the settler and the heat carrier heating furnace. The heat carrier is heated in the heat carrier heating furnace and then conveyed to the riser, and the high-temperature heat carrier and industrial gas are mixed and heat-exchanged in the riser and conveyed to the settler together. The heated industrial gas is discharged from the top outlet, and the heat carrier after heat release is sent back to the heat carrier heating furnace through the second conveying inclined pipe to be reheated. The system of the present application is applied to the heating of industrial gas, can be operated continuously for a long period of time, and has the advantages of fast heating speed, high heat exchange efficiency and simple system operation.

Description

Technical Field

[0001] The present invention relates to the technical field of gas heating, and in particular to an industrial gas heating system and method. Background Art

[0002] In the chemical, metallurgical, and energy industries, the gas preheating process has the advantages of greatly improving the efficiency of chemical reactions, reducing raw material consumption and energy consumption, and reducing carbon emissions, which is conducive to the efficient conversion and clean utilization of industrial fuels / raw materials. At present, gas heating in the industrial field mainly adopts fuel combustion heating or electric heating. The fuel combustion heating method usually adopts shell-and-tube heat exchange technology or heat storage technology. Among them, the former uses shell-and-tube or plate-type heat exchangers to continuously heat the gas, but there are problems such as low heat exchange temperature, low thermal efficiency, and carbon deposition when heating CO-containing gases, which can easily cause equipment blockage; the latter uses refractory heat storage bodies as intermediate heat carriers, and there are problems such as single-furnace intermittent operation (multiple furnaces need to be configured for alternating operation), complex operation, slow heating speed, and safety risks when heating certain reducing gases (such as coal gas, synthesis gas, ammonia, formaldehyde, etc.). The electric heating method mainly uses electric heat conversion technology to heat the gas, which has problems such as high energy consumption and low energy utilization.

[0003] In the field of metallurgical industry, the core of the recycling of furnace top gas is gas heating technology, which improves energy utilization by heating the residual chemical energy of the gas to a temperature of more than 850°C and reforming it to the smelting furnace. Internationally, Midrex and HYL's gas heating technology uses expensive metal tube heat exchangers, which can only heat hydrogen-rich gas to 800-950°C, and long-term use can easily cause H2 corrosion of the metal materials of the equipment, greatly increasing the cost of equipment maintenance and replacement. The EU "ULCOS" furnace top gas circulation experiment uses another indirect heat exchange process to heat the gas. Its heating principle is similar to that of the blast furnace hot blast furnace, but it is very easy to cause carbon deposition, causing bed blockage, affecting heat exchange efficiency, and due to intermittent operation, there is a high risk of deflagration. Patent document CN113720016A discloses a thermal storage gas heating technology, which first uses the heat generated by the combustion of the combustion medium to heat the refractory thermal storage body, and then uses the heated thermal storage body to heat the cold gas, and realizes continuous heating of the cold gas by configuring at least two thermal storage heating furnaces to operate alternately. However, because the thermal storage body is fixedly installed, the heat storage and heat release processes need to be intermittently alternated in the same space, which makes it have the defects of discontinuous heating of a single furnace, complex equipment operation, and poor system flexibility. In addition, there are also problems of slow heating rate and low overall energy efficiency of the system to a certain extent. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the existing thermal storage gas heating technology, such as discontinuous heating of a single furnace, slow heating speed and complicated equipment operation, and to provide an industrial gas heating system and method. The system and method of the present invention can realize continuous heating of industrial gas, and have the advantages of fast heating speed and simple equipment operation.

[0005] The present invention provides an industrial gas heating system, which comprises a gas heating furnace, a heat carrier heating furnace, a first conveying inclined pipe and a second conveying inclined pipe;

[0006] The gas heating furnace comprises a settler and a riser, wherein the riser is located at the lower part of the settler, the upper outlet of the riser passes through the lower shell of the settler and is arranged inside the settler, the lower part of the riser is provided with a heat carrier inlet and an industrial gas inlet arranged below the heat carrier inlet, and the top of the settler is provided with an industrial gas outlet;

[0007] A heat carrier feeding port is provided on the top of the heat carrier heating furnace;

[0008] The first conveying inclined pipe is arranged between the bottom of the heat carrier heating furnace and the heat carrier introduction port, and is used to convey the heat carrier heated by the heat carrier heating furnace to the heat carrier introduction port;

[0009] The riser is used to transport the heat carrier and industrial gas fed from the heat carrier inlet and the industrial gas inlet upward to the interior of the settler;

[0010] The second conveying inclined pipe is arranged between the bottom of the settler and the heat carrier heating furnace, and is used to convey the heat carrier deposited at the bottom of the settler to the heat carrier heating furnace;

[0011] The heat carrier inlet is arranged at a position lower than the connection position between the heat carrier heating furnace and the first conveying inclined pipe; the connection position between the heat carrier heating furnace and the second conveying inclined pipe is lower than the connection position between the settler and the second conveying inclined pipe.

[0012] In the present invention, a heat carrier discharge port may be further provided at the lower portion of the riser. Preferably, the heat carrier discharge port is provided at a position lower than the heat carrier introduction port.

[0013] In the present invention, a heating structure is provided on the heat carrier heating furnace, and the heating structure is used to heat the heat carrier in the heat carrier preheating furnace. The heating structure can adopt structure one, structure two or structure three, and preferably adopts structure one;

[0014] The first structure is to set a combustible gas inlet, a combustion-supporting gas inlet and a smoke outlet on the heat carrier heating furnace, wherein the combustible gas inlet and the combustion-supporting gas inlet are preferably arranged at the bottom of the heat carrier heating furnace, and the smoke outlet is preferably arranged at the top of the heat carrier heating furnace;

[0015] The second structure is to set an external heating device outside the heat carrier heating furnace, and the external heating device can be an electric heating device or a flame heating device, and the external heating device is used to heat the furnace body of the heat carrier heating furnace to indirectly heat the heat carrier;

[0016] The third structure is to arrange an internal heating device inside the heat carrier heating furnace, and the internal heating device is used to heat the heat carrier in the heat carrier heating furnace. The internal heating device can be a heat exchange tube bundle heating device or an electric heating device.

[0017] Furthermore, the industrial gas heating system may further include a degassing tank, the first conveying inclined pipe is divided into an upstream section and a downstream section by the degassing tank, the upstream section is arranged between the bottom of the heat carrier heating furnace and the degassing tank, and the downstream section is arranged between the degassing tank and the heat carrier inlet;

[0018] The degassing tank is provided with a purge gas inlet and a purge waste gas outlet, and the purge gas flow channel formed by the purge gas inlet and the purge waste gas outlet is used to remove impurity gases on the surface of the heat carrier flowing through the degassing tank;

[0019] The connection position between the degassing tank and the upstream section is lower than the connection position between the heat carrier heating furnace and the upstream section, and the setting position of the heat carrier introduction port is lower than the connection position between the degassing tank and the downstream section.

[0020] Wherein, the industrial gas heating system may further include a degassing tank exhaust pipe and a purge waste gas inlet arranged on the heat carrier heating furnace, and the degassing tank exhaust pipe is preferably arranged between the purge waste gas outlet and the purge waste gas inlet.

[0021] Wherein, the purge gas inlet is preferably arranged at the bottom of the degassing tank, and the purge exhaust gas outlet is preferably arranged at the top of the degassing tank.

[0022] Among them, the height of the degassing tank is h1, the connection position of the upstream section and the degassing tank is preferably set between 2 / 3h1 of the degassing tank and the top of the degassing tank, and the connection position of the downstream section and the degassing tank is preferably set between the bottom of the degassing tank and 1 / 3h1 of the degassing tank, and the 2 / 3h1 and the 1 / 3h1 are both calculated upward based on the bottom of the degassing tank.

[0023] Furthermore, the industrial gas heating system may further include a combustion-supporting gas pipeline, a combustible gas pipeline, an industrial gas intake pipeline and a flue gas pipeline, one end of the flue gas pipeline is connected to the flue gas outlet, and the flue gas pipeline may be sequentially provided with a first heat exchanger, a second heat exchanger and a third heat exchanger, preferably, the first heat exchanger, the second heat exchanger and the third heat exchanger may independently be a plate heat exchanger, a tube heat exchanger and a heat storage heat exchanger;

[0024] The combustion-supporting gas inlet is connected to the first heat exchanger through the combustion-supporting gas pipeline, the combustible gas inlet is connected to the second heat exchanger through the combustible gas pipeline, and the industrial gas inlet is connected to the third heat exchanger through the industrial gas intake pipeline.

[0025] In the present invention, the settler and the heat carrier heating furnace can be divided into an upper section, a transition section and a lower section from top to bottom. The inner diameter of the transition section gradually decreases from top to bottom, and the upper outlet of the riser is located in the upper section of the settler.

[0026] In the present invention, the diameter of the heat carrier heating furnace may be 4.0 m and the diameter of the riser may be 2.5 m, or the diameter of the heat carrier heating furnace may be 2.5 m and the diameter of the riser may be 1.2 m.

[0027] In the present invention, the height of the heat carrier heating furnace is h2, and the second conveying inclined pipe can be connected to the lower part of the heat carrier heating furnace, preferably connected to 1 / 5h2 to 1 / 2h2 of the heat carrier heating furnace, and the 1 / 5h2 and 1 / 2h2 are both calculated upward based on the bottom of the heat carrier heating furnace.

[0028] The present invention also provides an industrial gas heating method, which is performed using the above-mentioned gas heating system and comprises the following steps:

[0029] S1, the heat carrier fed from the heat carrier feeding port is heated and then transported to the heat carrier introduction port through the first transport inclined pipe;

[0030] S2, the industrial gas and the heat carrier respectively fed from the industrial gas inlet and the heat carrier inlet are mixed in the riser for heat exchange and transported upward to the settler;

[0031] The industrial gas heated in S3 and S2 is discharged from the industrial gas outlet, and the heat carrier after releasing heat is deposited in the settler and then transported to the heat carrier heating furnace through the second transport inclined pipe;

[0032] S4, the heat carrier from the settler is reheated in the heat carrier heating furnace and then transported to the heat carrier inlet through the first transport inclined pipe;

[0033] According to the cycle of steps S4-S2-S3, the heat carrier is circulated and transported between the heat carrier heating furnace and the gas heating furnace, and the industrial gas is heated.

[0034] In the present invention, in step S1, the heat carrier may be refractory solid particles, the thermal conductivity of the refractory solid particles is ≥ 0.1 W / (m·K), the surface heat transfer coefficient is ≥ 300 W / (m 2 ·K), heat capacity ≥500J / (kg·K), preferably one or more of quartz sand, iron oxide powder and aluminum oxide powder, more preferably quartz sand.

[0035] In the present invention, in step S1, the particle size of the heat carrier particles may be 50-500 μm, preferably 50-100 μm.

[0036] In the present invention, in step S1, the heating may be carried out by way one, way two or way three, and way one is preferably adopted. Way one is an operation of directly heating the heat carrier by passing the combustible gas and the combustion-supporting gas into the heat carrier heating furnace to generate a combustion reaction, way two is an operation of indirectly heating the heat carrier by externally heating the furnace body of the heat carrier heating furnace, and way three is an operation of indirectly heating the heat carrier by arranging a heat exchange tube bundle or an electric heater inside the heat carrier heating furnace.

[0037] Furthermore, in step S1, the heated heat carrier may be first transported to the degassing tank, and then transported to the heat carrier inlet after purification, wherein the purification is an operation of removing impurity gases on the surface of the heat carrier by using a purge gas.

[0038] The purge gas may be one or more of CO2, N2 and rare gases, preferably N2.

[0039] The purge exhaust gas generated by the purification can be discharged into the heat carrier heating furnace.

[0040] Furthermore, the high-temperature flue gas generated by the combustion reaction can be transported to three heat exchangers connected in series to preheat the combustible gas, the combustion-supporting gas and the industrial gas respectively.

[0041] Furthermore, the combustible gas may include one or more of CH4, CO and H2.

[0042] Furthermore, the combustion-supporting gas may be one or more of air and oxygen, preferably air.

[0043] Furthermore, the temperature of the combustion reaction may be 700-1800°C, preferably 1100-1500°C.

[0044] Furthermore, the pressure of the combustion reaction may be 0.1 to 1.0 MPa, preferably 0.2 to 0.5 MPa.

[0045] Furthermore, the outlet temperature of the high-temperature flue gas generated by the combustion reaction may be 600-1500°C.

[0046] In the present invention, in step S2, the temperature of the heated heat carrier may be 500-1500°C.

[0047] In the present invention, in step S2, the industrial gas may be one or more of air, ammonia, gasification synthesis gas, blast furnace gas, decarbonized gas and coke oven gas.

[0048] In the present invention, in step S2, the pressure of the industrial gas introduced into the industrial gas inlet of the riser can be 0.5-1.5 MPa.

[0049] In the present invention, in step S2, the working pressure of the riser can be 0.1-1.0 MPa.

[0050] In the present invention, in step S3, the temperature of the industrial gas discharged from the industrial gas outlet may be 600-1500°C.

[0051] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.

[0052] The reagents and raw materials used in the present invention are commercially available.

[0053] The positive and progressive effects of the present invention are:

[0054] (1) The present invention uses solid heat carrier particles as circulating heat transfer medium, which can achieve single furnace continuous operation and long-term system operation under the premise of ensuring the heating temperature. It also has the advantages of switching industrial gases without stopping the furnace and simple operation.

[0055] (2) In the present invention, the heat carrier particles and the industrial gas can achieve direct and dynamic heat exchange in the riser, which can not only ensure high heat exchange efficiency but also increase the gas heating speed.

[0056] (3) The heat carrier circulation power design of the present invention is semi-active and semi-passive. The gravitational potential energy generated by the height difference of each device in the system is used to realize the heat carrier transportation between the two devices, and the ramming kinetic energy of the industrial gas is used to realize the heat exchange between the heat carrier and the industrial gas. The gas-solid separation is then carried out through the settler, and finally the purpose of circulating and transporting the heat carrier is achieved. There is no need to configure an additional heat carrier transportation power device. The system design is simple and ingenious, and the operation is convenient.

[0057] (4) In the optimized design of the present invention, by designing the heat carrier discharge port, the heat carrier flow rate in the system can be flexibly adjusted to adapt to the changes in the heat load of the industrial gas. Different heat carrier materials can also be matched and replaced according to the type of industrial gas, and the system flexibility is excellent.

[0058] (5) In the optimized design of the present invention, the degassing tank is designed to purify the high-temperature heat carrier particles directly heated by the flame, so that the industrial gas is not contaminated during the heat exchange with the heat carrier body, while also ensuring the safety of the system operation when heating flammable and explosive gases.

[0059] (6) In the optimized design of the present invention, by designing a secondary recovery and utilization device for the residual heat energy of high-temperature waste flue gas, the high-temperature flue gas generated by the combustion in the heat carrier heating furnace is used to preheat the raw gas and industrial gas, which can greatly improve the overall energy efficiency of the system and have a certain energy-saving and consumption-reducing effect.

[0060] (7) In the optimized design of the present invention, by selecting quartz sand with high thermal conductivity, large specific surface area, large specific heat capacity and good stability as the heat carrier material, the heating speed and heat exchange efficiency can be further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 This is the layout diagram of the industrial gas heating system of Example 1.

[0062] Description of Reference Numerals

[0063] Gas heating furnace 1, settler 11, industrial gas outlet 110, riser 12, industrial gas inlet 120, heat carrier inlet 121, heat carrier discharge port 122, upper outlet 123 of riser, heat carrier heating furnace 2, heat carrier feeding port 20, combustion-supporting gas inlet 21, combustible gas inlet 22, flue gas outlet 23, purge waste gas inlet 24, first conveying inclined pipe 31, upstream section 311, downstream section 312, second conveying inclined pipe 32, degassing tank 4, purge gas inlet 41, purge waste gas outlet 42, degassing tank exhaust pipe 5, industrial gas inlet pipe 6, combustion-supporting gas pipe 71, combustible gas pipe 72, flue gas pipe 73, first heat exchanger 81, second heat exchanger 82, third heat exchanger 83, heat carrier 9 DETAILED DESCRIPTION

[0064] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples. The experimental methods in the following examples without specifying specific conditions are carried out according to conventional methods and conditions, or selected according to the product instructions.

[0065] Embodiment 1 provides a specific example of an industrial gas heating system of the present invention. The gas heating methods used in Embodiments 2 to 4 are performed in the system device described in Embodiment 1. The accompanying drawings are only used for illustrative purposes and only schematic diagrams are shown instead of actual diagrams. The terms used in the present invention to describe the positional relationship are also only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in the field, the specific meaning of the positional relationship terms can be understood according to specific circumstances.

[0066] Example 1 Gas Heating System

[0067] like Figure 1 The industrial gas heating system shown includes a gas heating furnace 1, a heat carrier heating furnace 2, a first conveying inclined pipe 31, a second conveying inclined pipe 32, a degassing tank 4, a first heat exchanger 81, a second heat exchanger 82, a third heat exchanger 83, a degassing tank exhaust pipe 5, an industrial gas inlet pipe 6, a combustion-supporting gas pipe 71, a combustible gas pipe 72 and a flue gas pipe 73.

[0068] The gas heating furnace 1 includes a settler 11 and a riser 12. The upper outlet 123 of the riser passes through the lower part of the settler 11 and is arranged inside the settler 11. The lower part of the riser 12 is provided with a heat carrier inlet 121 and an industrial gas inlet 120 and a heat carrier discharge port 122 arranged below the heat carrier inlet 121. The top of the settler 11 is provided with a heat carrier feeding port 20 and a flue gas outlet 23. The bottom is provided with a combustion-supporting gas inlet 21 and a combustible gas inlet 22. The upper part of the heat carrier heating furnace 2 is also provided with a purge waste gas inlet 24. The settler 11 and the heat carrier heating furnace 2 are divided into an upper section, a transition section and a lower section from top to bottom. The inner diameter of the upper section is larger than the inner diameter of the lower section. The inner diameter of the transition section gradually decreases from top to bottom. The upper outlet 123 of the riser is located in the upper section of the settler 11.

[0069] The first conveying inclined pipe 31 is divided into an upstream section 311 and a downstream section 312 by the degassing tank 4. The upstream section 311 connects the bottom of the heat carrier heating furnace 2 and the degassing tank 4, and the downstream section 312 connects the heat carrier inlet 121 and the degassing tank 4. The connection position of the degassing tank 4 and the upstream section 311 is lower than the connection position of the heat carrier heating furnace 2 and the upstream section 311, and the setting position of the heat carrier inlet 121 is lower than the connection position of the degassing tank 4 and the downstream section 312. The height of the degassing tank 4 is h1, and the connection position of the upstream section 311 and the degassing tank 4 is set between 2 / 3h1 of the degassing tank 4 and the top of the degassing tank 4, and the connection position of the downstream section 312 and the degassing tank 4 is set between the bottom of the degassing tank 4 and the 1 / 3h1 of the degassing tank 4, and 2 / 3h1 and 1 / 3h1 are both calculated upward based on the bottom of the degassing tank 4.

[0070] A purge gas inlet 41 is provided at the bottom of the degassing tank 4 , and a purge waste gas outlet 42 is provided at the top. The degassing tank exhaust pipe 5 connects the purge waste gas outlet 42 and the purge waste gas inlet 24 .

[0071] The second conveying inclined pipe 32 connects the bottom of the settler 11 and the lower part of the heat carrier heating furnace 2. The height of the heat carrier heating furnace 2 is h2, and the second conveying inclined pipe 32 is connected to the heat carrier heating furnace 2 at 1 / 5h2 to 1 / 2h2, and 1 / 5h2 and 1 / 2h2 are both calculated upward based on the bottom of the heat carrier heating furnace 2. The connection position of the heat carrier heating furnace 2 and the second conveying inclined pipe 32 is lower than the connection position of the settler 11 and the second conveying inclined pipe 32.

[0072] One end of the flue gas duct 73 is connected to the flue gas outlet 23, and a first heat exchanger 81, a second heat exchanger 82 and a third heat exchanger 83 are sequentially arranged on the flue gas duct 73. The combustion-supporting gas inlet 21 is connected to the first heat exchanger 81 through the combustion-supporting gas duct 71, the combustible gas inlet 22 is connected to the second heat exchanger 82 through the combustible gas duct 7272, and the industrial gas inlet 120 is connected to the third heat exchanger 83 through the industrial gas intake duct 6.

[0073] The heat carrier 9 is quartz sand with a particle size range of 50 to 100 μm. The heat carrier 9 is introduced into the system from the heat carrier feeding port 20 and can be discharged from the system from the heat carrier discharging port 122 .

[0074] Example 2 Gas Heating Method

[0075] The system device of Example 1 is used to heat the industrial gas, and the specific steps are as follows:

[0076] The combustion-supporting gas and the combustible gas are introduced into the heat carrier heating furnace 2 through the combustion-supporting gas pipeline 71 and the combustible gas pipeline 72 respectively to generate a combustion reaction. The heat carrier 9 is introduced into the heat carrier heating furnace 2 from the heat carrier feeding port 20, and the combustion reaction heats the heat carrier 9. The heated heat carrier 9 is sent to the degassing tank 4 for purification through the upstream section 311 of the first conveying inclined pipe 31, and the purified heat carrier 9 is sent to the heat carrier introduction port 121 through the downstream section 312 of the first conveying inclined pipe 31. In the riser 12, the heat carrier 9 exchanges heat with the industrial gas introduced through the industrial gas inlet pipeline 6, and the heat carrier 9 and the industrial gas are transported to the settler 11 together. The heated industrial gas is discharged from the system from the industrial gas outlet 110, and the heat carrier 9 after releasing heat settles in the settler 11 and is sent back to the heat carrier heating furnace 2 through the second conveying inclined pipe 32.

[0077] At the same time, the high-temperature flue gas discharged from the flue gas outlet 23 is transported to the first heat exchanger 81, the second heat exchanger 82 and the third heat exchanger 83 through the flue gas pipeline 73 to preheat the combustion-supporting gas, the combustible gas and the industrial gas respectively. The preheated combustion-supporting gas and the combustible gas are respectively introduced into the heat carrier heating furnace 2 through the combustion-supporting gas pipeline 71 and the combustible gas pipeline 72, and the preheated industrial gas is transported to the riser 12 through the industrial gas intake pipeline 6.

[0078] At the same time, nitrogen is introduced into the degassing tank 4 from the purge gas inlet 41 to purify the heated heat carrier 9 and remove the flue gas, combustible gas and combustion-supporting gas on its surface. The purge waste gas is discharged from the purge waste gas outlet 42 and discharged into the heat carrier heating furnace 2 through the degassing tank exhaust pipe 5.

[0079] Example 3

[0080] The heat carrier 9 used in this embodiment is quartz sand (i.e. SiO2 particles), and its physical properties are shown in Table 1. The combustible gas used is low-quality coal gas, the combustion-supporting gas is air, and the industrial gas to be heated is decarbonized blast furnace gas. The chemical composition and working conditions of each gas are shown in Table 2, and the pressure in the table is the gas pressure introduced at the industrial gas inlet 120 at the lower part of the riser.

[0081] Table 1 Physical parameters of quartz sand

[0082] project parameter project parameter <![CDATA[Purity of SiO2]]> >99.5％ Heat capacity ~800J / kg K <![CDATA[Particle size range of SiO2]]> 50~100μm Thermal conductivity ~3W / m K Wear rate <1％ Melting point 1750℃ Mud content <0.5％ hardness 7 density <![CDATA[2.65g / cm 3 ]]> Heat exchange time 0.05～0.68s Heat transfer coefficient <![CDATA[25-500W / m 2 K]]>

[0083] Table 2 Chemical composition and working conditions of each gas

[0084]

[0085] This embodiment adopts the gas heating method of embodiment 2 to heat blast furnace gas, and the method is as follows:

[0086] The inferior coal gas and air shown in Table 2 are introduced into the heat carrier heating furnace 2 for combustion reaction. The air flow rate is 9420 Nm 3 / h, the flow rate of combustible gas is 12920Nm 3 / h, the diameter of the heat carrier heating furnace 2 is 4.0m, the reaction pressure in the heat carrier heating furnace 2 is 0.5MPa, and the temperature of the combustion reaction is controlled at 1400℃.

[0087] The high-temperature flue gas (the temperature of the flue gas outlet 23 is 1200°C) generated by combustion is preheated in turn through the first heat exchanger 81, the second heat exchanger 82 and the third heat exchanger 83 to preheat the air, the low-quality coal gas and the blast furnace gas. The temperature of the air is increased from 25°C to 1100°C, the temperature of the low-quality coal gas is increased from 25°C to 490°C, the temperature of the blast furnace gas is increased from 25°C to 490°C, and the final outlet temperature of the flue gas is lower than 170°C.

[0088] The SiO2 particles are introduced into the heat carrier heating furnace 2 and heated to 1400°C by the combustion reaction. The high-temperature SiO2 particles are transported to the degassing tank 4 for purification. The high-temperature SiO2 particles purged with nitrogen are transported to the riser 12 for heating the preheated blast furnace gas. The diameter of the riser 12 is 2.5m, the pressure in the riser 12 is 0.5MPa, and the flow rate of the blast furnace gas in the riser 12 is 55000Nm 3 / h, the circulation amount of heat carrier SiO2 particles is 260t / h. The heat carrier circulation amount is the weight of the heat carrier passing through the cross section of the riser 12 per unit time.

[0089] The high-temperature SiO2 particles and blast furnace gas are fully mixed and heat exchanged in the riser 12. At the same time, the SiO2 particles are carried by the blast furnace gas flow to the settler 11. The SiO2 particles after releasing heat settle in the settler 11 and are re-transported to the heat carrier heating furnace 2 through the second conveying inclined pipe 32. The heated blast furnace gas is discharged from the industrial gas outlet 110 at the top of the settler 11. The blast furnace gas outlet temperature is 1200°C.

[0090] The operating parameters and energy efficiency calculation results of the blast furnace gas heating process in this embodiment are shown in Table 3.

[0091] Table 3 Target blast furnace gas heating process operating parameters

[0092] project parameter Blast furnace gas flow <![CDATA[55000Nm 3 / h]]> Combustion air flow <![CDATA[9420Nm 3 / h]]> Combustible gas flow <![CDATA[12920Nm 3 / h]]> <![CDATA[SiO2 recycle flow rate]]> 260t / h Heat carrier heating furnace diameter 4.0m Riser diameter 2.5m System Energy Efficiency >95％

[0093] Example 4

[0094] The heat carrier used in this embodiment is the same as that in Embodiment 3. The combustible gas used is low-quality coal gas, and the combustion-supporting gas and the industrial gas to be heated are both air. The composition of each gas is shown in Table 4.

[0095] Table 4 Chemical composition of inferior gas and air

[0096]

[0097] This embodiment adopts the gas heating method of embodiment 2 to heat the air, and the method is as follows:

[0098] The inferior coal gas and combustion-supporting air shown in Table 2 are introduced into the heat carrier heating furnace 2 for combustion reaction. The flow rate of the combustion-supporting air is 3060.7 Nm 3 / h, the flow rate of inferior gas is 4285.0Nm 3 / h, the diameter of the heat carrier heating furnace 2 is 2.5m, the reaction pressure in the heat carrier heating furnace 2 is 0.4MPa, and the temperature of the combustion reaction is controlled at 1460℃.

[0099] The high-temperature flue gas generated by combustion (the temperature of the flue gas outlet 23 is 1200°C) is preheated in turn through the first heat exchanger 81, the second heat exchanger 82 and the third heat exchanger 83 to preheat the combustion air, the inferior coal gas and the target air. The temperature of the combustion air is increased from 20°C to 1100°C, the temperature of the inferior coal gas is increased from 25°C to 490°C, the temperature of the air is increased from 20°C to 480°C, and the final outlet temperature of the flue gas is lower than 100°C.

[0100] The SiO2 particles are introduced into the heat carrier heating furnace 2 and heated to 1450°C by the combustion reaction. The high-temperature SiO2 particles are transported to the degassing tank 4 for purification. The high-temperature SiO2 particles purged with nitrogen are transported to the riser 12 to heat the preheated target air. The diameter of the riser 12 is 1.2m, the pressure in the riser 12 is 0.4Mpa, and the flow rate of the target air in the riser 12 is 10000Nm 3 / h, the circulation amount of SiO2 particles is 111.0t / h.

[0101] The high-temperature SiO2 particles and the target air are fully mixed and heat exchanged in the riser 12. At the same time, the SiO2 particles are carried by the target air flow to the settler 11. The SiO2 particles after releasing heat settle in the settler 11 and are re-transported to the heat carrier heating furnace 2 through the second conveying inclined pipe 32. The heated target air is discharged from the industrial gas outlet 110 at the top of the settler 11. The outlet temperature of the target air is 1300°C.

[0102] The operating parameters and energy efficiency calculation results of the air heating process in this embodiment are shown in Table 5.

[0103] Table 5 Target air heating process operating parameters

[0104] project parameter Target air flow <![CDATA[10000Nm 3 / h]]> Combustion air flow <![CDATA[3060.7Nm 3 / h]]> Poor quality gas flow <![CDATA[4285.0Nm 3 / h]]> <![CDATA[SiO2 recycle amount]]> 111.0t / h Heat carrier heating furnace diameter 2.5m Riser diameter 1.2m System Energy Efficiency >95％

[0105] In Examples 3 and 4 of the present invention, a small amount of combustible gas is used to burn and heat the heat carrier SiO2 particles, and then the heat carrier SiO2 particles are circulated and transported in the system to achieve continuous heating of industrial gas. In Example 3, the decarbonized blast furnace gas is heated to 1200° C., and in Example 4, the target air is heated to 1300° C. The heat medium selected in the present invention is a solid heat carrier with stable properties, high temperature resistance and good circulation. By controlling the heat carrier flow in the system, it can adapt to the load changes of industrial gas.

[0106] Heating gas using the industrial gas heating method of the present invention can not only ensure high heating temperature and good system safety, but also has the advantages of continuous long-term operation, simple operation, fast heating speed, good system flexibility, and high system comprehensive energy efficiency. It can also reduce raw material consumption to a certain extent, thereby achieving the effect of energy saving and consumption reduction.

[0107] The present invention is not limited to the above-mentioned embodiments. Any changes in shape or structure are within the protection scope of the present invention. The protection scope of the present invention is defined by the attached claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principle and essence of the present invention, but these changes and modifications are within the protection scope of the present invention.

Claims

1. An industrial gas heating system, characterized in that: It includes a gas heating furnace, a heat carrier heating furnace, a first conveying inclined pipe and a second conveying inclined pipe; The gas heating furnace comprises a settler and a riser, wherein the riser is located at the lower part of the settler, the upper outlet of the riser passes through the lower shell of the settler and is arranged inside the settler, the lower part of the riser is provided with a heat carrier inlet and an industrial gas inlet arranged below the heat carrier inlet, and the top of the settler is provided with an industrial gas outlet; the lower part of the riser is provided with a heat carrier discharge port, and the setting position of the heat carrier discharge port is lower than the setting position of the heat carrier inlet; A heat carrier feeding port is provided on the top of the heat carrier heating furnace; The first conveying inclined pipe is arranged between the bottom of the heat carrier heating furnace and the heat carrier introduction port, and is used to convey the heat carrier heated by the heat carrier heating furnace to the heat carrier introduction port; The riser is used to transport the heat carrier and industrial gas fed from the heat carrier inlet and the industrial gas inlet upward to the interior of the settler; The second conveying inclined pipe is arranged between the bottom of the settler and the heat carrier heating furnace, and is used to convey the heat carrier deposited at the bottom of the settler to the heat carrier heating furnace; The heat carrier inlet is arranged at a position lower than the connection position between the heat carrier heating furnace and the first conveying inclined pipe; the connection position between the heat carrier heating furnace and the second conveying inclined pipe is lower than the connection position between the settler and the second conveying inclined pipe; The industrial gas heating system further comprises a degassing tank, wherein the first conveying inclined pipe is divided into an upstream section and a downstream section by the degassing tank, wherein the upstream section is arranged between the bottom of the heat carrier heating furnace and the degassing tank, and the downstream section is arranged between the degassing tank and the heat carrier inlet; The connection position between the degassing tank and the upstream section is lower than the connection position between the heat carrier heating furnace and the upstream section, and the setting position of the heat carrier introduction port is lower than the connection position between the degassing tank and the downstream section; The degassing tank is provided with a purge gas inlet and a purge waste gas outlet. The purge gas flow channel formed by the purge gas inlet and the purge waste gas outlet is used to remove impurity gases on the surface of the heat carrier flowing through the degassing tank.

2. The industrial gas heating system according to claim 1, characterized in that: The heat carrier heating furnace is provided with a heating structure, and the heating structure is used to heat the heat carrier in the heat carrier heating furnace, and the heating structure adopts structure one, structure two or structure three; The first structure is to set a combustible gas inlet, a combustion-supporting gas inlet and a smoke outlet on the heat carrier heating furnace, wherein the combustible gas inlet and the combustion-supporting gas inlet are arranged at the bottom of the heat carrier heating furnace, and the smoke outlet is arranged at the top of the heat carrier heating furnace; The second structure is to set an external heating device outside the heat carrier heating furnace, the external heating device is an electric heating device or a flame heating device, and the external heating device is used to heat the furnace body of the heat carrier heating furnace to indirectly heat the heat carrier; The third structure is to set an internal heating device inside the heat carrier heating furnace, and the internal heating device is an electric heating device or a heat exchange tube bundle heating device.

3. The industrial gas heating system according to claim 2, characterized in that: The heating structure adopts structure one.

4. The industrial gas heating system according to claim 2, characterized in that: It comprises a degassing tank exhaust pipe and a purge waste gas inlet arranged on the heat carrier heating furnace, wherein the degassing tank exhaust pipe is arranged between the purge waste gas outlet and the purge waste gas inlet; And / or, the purge gas inlet is arranged at the bottom of the degassing tank, and the purge exhaust gas outlet is arranged at the top of the degassing tank; And / or, the height of the degassing tank is h1, the connection position between the upstream section and the degassing tank is set between 2 / 3 h1 of the degassing tank and the top of the degassing tank, and the connection position between the downstream section and the degassing tank is set between the bottom of the degassing tank and 1 / 3 h1 of the degassing tank.

5. The industrial gas heating system according to any one of claims 2 to 4, characterized in that: It comprises a combustion-supporting gas pipeline, a combustible gas pipeline, an industrial gas intake pipeline and a flue gas pipeline, one end of the flue gas pipeline is connected to the flue gas outlet, and the flue gas pipeline is sequentially provided with a first heat exchanger, a second heat exchanger and a third heat exchanger; The combustion-supporting gas inlet is connected to the first heat exchanger through the combustion-supporting gas pipeline, the combustible gas inlet is connected to the second heat exchanger through the combustible gas pipeline, and the industrial gas inlet is connected to the third heat exchanger through the industrial gas intake pipeline.

6. The industrial gas heating system according to claim 5, characterized in that: The first heat exchanger, the second heat exchanger and the third heat exchanger are independently one of a plate heat exchanger, a tube heat exchanger and a heat storage heat exchanger.

7. The industrial gas heating system according to any one of claims 1 to 4, characterized in that: The settler and the heat carrier heating furnace are divided into an upper section, a transition section and a lower section from top to bottom, the inner diameter of the transition section gradually decreases from top to bottom, and the upper outlet of the riser is located in the upper section of the settler; and / or, the diameter of the heat carrier heating furnace is 4.0 m and the diameter of the riser is 2.5 m; And / or, the height of the heat carrier heating furnace is h2, and the second conveying inclined pipe is connected to the lower part of the heat carrier heating furnace.

8. The industrial gas heating system according to claim 7, characterized in that: The height of the heat carrier heating furnace is h2, and the second conveying inclined pipe is connected to the heat carrier heating furnace at 1 / 5 h2 to 1 / 2 h2.

9. The industrial gas heating system according to claim 7, characterized in that: The diameter of the heat carrier heating furnace is 2.5 m and the diameter of the riser is 1.2 m.

10. An industrial gas heating method, characterized in that: The method is carried out using the industrial gas heating system according to any one of claims 1 to 9, and comprises the following steps: S1, the heat carrier fed from the heat carrier feeding port is heated and then transported to the heat carrier introduction port through the first transport inclined pipe; S2, the industrial gas and the heated heat carrier respectively fed from the industrial gas inlet and the heat carrier inlet are mixed in the riser for heat exchange and transported upward to the settler; The industrial gas heated in S3 and S2 is discharged from the industrial gas outlet, and the heat carrier after releasing heat is deposited in the settler and then transported to the heat carrier heating furnace through the second transport inclined pipe; S4, the heat carrier from the settler is reheated in the heat carrier heating furnace and then transported to the heat carrier inlet through the first transport inclined pipe; According to the cycle of steps S4-S2-S3, the heat carrier is circulated and transported between the heat carrier heating furnace and the gas heating furnace, and the industrial gas is heated.

11. The industrial gas heating method according to claim 10, characterized in that: In step S1, the heat carrier is refractory solid particles, the thermal conductivity of the refractory solid particles is ≥ 0.1 W / (m·K), and the surface heat transfer coefficient is ≥ 300 W / (m 2 ·K), heat capacity ≥500 J / (kg·K); And / or, in step S1, the particle size of the heat carrier particles is 50-500 μm; And / or, in step S1, the heating adopts mode 1, mode 2 or mode 3; mode 1 is an operation of directly heating the heat carrier by introducing the combustible gas and the combustion-supporting gas into the heat carrier heating furnace to generate a combustion reaction; mode 2 is an operation of indirectly heating the heat carrier by externally heating the furnace body of the heat carrier heating furnace; mode 3 is an operation of indirectly heating the heat carrier by arranging a heat exchange tube bundle or an electric heater inside the heat carrier heating furnace; And / or, in step S2, the temperature of the heated heat carrier is 500-1500° C.; And / or, in step S2, the industrial gas is one or more of air, ammonia, gasification synthesis gas, blast furnace gas, decarbonized coal gas and coke oven gas; And / or, in step S2, the pressure of the industrial gas introduced into the industrial gas inlet of the riser is 0.5-1.5 MPa; And / or, in step S2, the working pressure of the riser is 0.1-1.0 Mpa; And / or, in step S3, the temperature of the industrial gas discharged from the industrial gas outlet is 600-1500°C.

12. The industrial gas heating method according to claim 11, characterized in that: The heat carrier is one or more of quartz sand, iron oxide powder and aluminum oxide powder; And / or, in step S1, the particle size of the heat carrier particles is 50-100 μm; And / or, in step S1, the heating adopts the method 1.

13. The industrial gas heating method according to claim 12, characterized in that: The heat carrier is quartz sand.

14. The industrial gas heating method according to claim 11, characterized in that: In step S1, the heated heat carrier is first transported to a degassing tank, and then transported to the heat carrier inlet after purification, wherein the purification is an operation of removing impurity gases on the surface of the heat carrier by using a purge gas; and / or, conveying the high-temperature flue gas generated by the combustion reaction to three heat exchangers connected in series to preheat the combustible gas, the combustion-supporting gas and the industrial gas respectively; And / or, the combustible gas includes one or more of CH4, CO and H2; And / or, the combustion-supporting gas is one or more of air and oxygen; And / or, the temperature of the combustion reaction is 700-1800°C; And / or, the pressure of the combustion reaction is 0.1~1.0 Mpa; And / or, the outlet temperature of the high-temperature flue gas generated by the combustion reaction is 600-1500°C.

15. The industrial gas heating method according to claim 14, characterized in that: The purge gas is one or more of CO2, N2 and rare gas; and / or, the purge exhaust gas generated by the purification is discharged into the heat carrier heating furnace; And / or, the combustion-supporting gas is air; And / or, the temperature of the combustion reaction is 1100° C. to 1500° C.; And / or, the pressure of the combustion reaction is 0.2~0.5MPa.

16. The industrial gas heating method according to claim 15, characterized in that: The purge gas is N2.

Images