Green-electricity zero-carbon desulfurization building gypsum production system

Abstract

The utility model relates to a green-electricity zero-carbon desulfurization building gypsum production system which comprises a chimney, an induced draft fan, a bag collector, a high-temperature fan, a cyclone I, a scattering dryer, a cyclone II, a green-electricity furnace and a cyclone III. According to the utility model, green electricity is used as an energy source, the desulfurization building gypsum is produced by adopting a suspension calcination technology, zero-carbon production of the desulfurization gypsum is facilitated, and carbon neutralization in the building gypsum industry is realized.

Description

Technical Field

[0001] The utility model relates to a system for producing building gypsum with zero carbon from desulfurized gypsum. Background Art

[0002] Gypsum is a sulfate mineral resource widely existing in nature. Also, gypsum is a cementitious material with a long history and is listed as one of the three major pillars among inorganic cementitious materials together with lime and cement. Desulfurized gypsum is the product of flue gas desulfurization by the limestone / gypsum method in thermal power plants and is dihydrate gypsum. At present, the output of desulfurized gypsum in China is about 80 million tons, and the problems of treatment and comprehensive utilization of desulfurized gypsum have become increasingly urgent. At present, desulfurized gypsum is mainly applied to the manufacture of paper-faced gypsum board, putty gypsum and plaster for rendering, cement retarder, etc.

[0003] In the CaSO 4 -H 2 O system, generally recognized gypsum phases have five forms and seven variants, which are dihydrate gypsum (CaSO 4 ·2H 2 O); α-type and β-type hemihydrate gypsum (α-CaSO 4 ·0.5H 2 O, β-CaSO 4 ·0.5H 2 O); α-type and β-type anhydrite III (α-CaSO 4 III, β-CaSO 4 III), type II anhydrite (CaSO 4 II) and type I anhydrite (CaSO 4 I). α-type and β-type anhydrite III are easily transformed into α-type and β-type hemihydrate gypsum in a humid environment at 20-180°C. β-type hemihydrate gypsum, namely building gypsum, has good ductility and plasticity, is easy to harden and form, has a microporous structure, good water retention and strong hygroscopicity, and is commonly used in the production of paper-faced gypsum board.

[0004] At present, the production process of building gypsum mainly uses a fluidized bed furnace, but its gypsum calcination time is long and the production energy consumption is high. It is urgent to develop a new calcination process. The fuel used for producing building gypsum is mainly fossil fuel, which emits carbon dioxide. In addition, the heat transfer of the fluidized bed furnace is indirect heat transfer, that is, the fuel heats the flue gas, and the flue gas then transfers the heat to the gypsum. Since the specific heat of the flue gas is low, a large amount of flue gas is required to obtain qualified products. Due to the large amount of flue gas, a lot of heat is carried away after the flue gas is discharged, resulting in high energy consumption.

[0005] Wind power, photovoltaic power generation and solar thermal power generation, namely green electricity, are renewable clean energy. At present, there is no production system that uses green electricity to produce desulfurized building gypsum. This system also has the characteristics of high production efficiency, low equipment investment and less site use. Green electricity is stored in a sodium ion battery system, which has the characteristics of low cost and stable electricity. Photovoltaic power generation is located in photovoltaic power plants, wind power generation is located in wind power plants, and solar thermal power generation is located in solar thermal power plants. The green electricity from different power plants is connected to the sodium ion battery system in the gypsum production company through aluminum wires, and the sodium ion battery system is connected to the gypsum production equipment system through aluminum wires. The steam from the solar thermal power plant is connected to the gypsum system through pipelines. Utility Model Content

[0006] The technical problem to be solved by the utility model is to provide a green electricity zero-carbon production desulfurized building gypsum system with high production efficiency and realize carbon neutrality in the production of desulfurized building gypsum.

[0007] The technical solution adopted by the utility model to solve its technical problems is:

[0008] A green electricity zero-carbon production desulfurized building gypsum system comprises a chimney, an induced draft fan, a bag dust collector, a high-temperature fan, a cyclone I, a dispersing dryer, a cyclone II, a green electric furnace, and a cyclone III; characterized in that the chimney is connected to the outlet of the induced draft fan, the inlet of the induced draft fan is connected to the outlet of the bag dust collector, the inlet of the bag dust collector is connected to the outlet of the high-temperature fan, the inlet of the high-temperature fan is connected to the outlet of the cyclone I, the inlet of the cyclone I is connected to the outlet of the dispersing dryer, the inlet of the dispersing dryer is connected to the outlet of the cyclone II, the inlet of the cyclone II is connected to the outlet of the green electric furnace, and the inlet of the green electric furnace is connected to the outlet of the cyclone III; the green electric furnace consists of a furnace body, a furnace cover and a furnace bottom, and the furnace body comprises a green electricity heating element, a heat insulating material and a furnace body shell.

[0009] The electric energy used by the green electric furnace is one of photovoltaic power generation, wind power generation and solar thermal power generation.

[0010] The green electric heating element is composed of a heating element, a protective tube, a motherboard and a cover plate; wherein the material of the heating element is one of iron-chromium-aluminum alloy and nickel-chromium alloy, the material of the protective tube is one of mullite and cordierite, and the materials of the motherboard and the cover plate are composite ceramics prepared by mixing and sintering silicon carbide, silicon nitride, zirconium silicate and quartz.

[0011] The heat insulating material is one of mullite fiber and alumina fiber.

[0012] The furnace cover and furnace bottom are composed of high-alumina cement refractory casting material and a shell.

[0013] The green electric furnace can also directly use the steam from the solar thermal power generation system as a heat source.

[0014] Compared with the prior art, the advantages of the present utility model are as follows:

[0015] The chimney is made of steel pipe, which is a hollow cylinder. The inner and outer walls of the steel pipe are sprayed with high-temperature resistant paint. The working temperature of the high-temperature resistant paint is 100 - 180 °C, and the high-temperature resistant paint can improve the service life of the chimney. The high-temperature resistant paint is one of epoxy phenolic paint and silicone high-temperature resistant paint, both of which can achieve the purpose.

[0016] The induced draft fan is a centrifugal boiler induced draft fan, with a working temperature of 150 - 250 °C, made of stainless steel, having the characteristics of corrosion resistance; it also has the characteristics of stable operation and low energy consumption.

[0017] The bag filter is a high-temperature air box pulse bag filter. The filter bag is made of high-temperature resistant basalt fiber, with a working temperature of 150 - 250 °C, and the dust concentration at the outlet is less than 10 mg / Nm 3 With this characteristic, the tail gas can meet the emission standards.

[0018] The high-temperature fan is a high-temperature centrifugal fan, with a working temperature of 200 - 350 °C, made of stainless steel, having the characteristics of corrosion resistance; it also has the characteristics of stable operation and low energy consumption.

[0019] The cyclone is designed and manufactured according to the structural principle of the Smith-type cyclone, having the characteristics of low air flow resistance and energy-saving operation, and is used for gas-solid separation of gas containing powder materials. The inside of the cyclone and the pipeline are lined with aluminous cement castable, which has the function of protecting the carbon steel shell of the cyclone and the pipeline and avoiding heat loss. The cyclone I collects the materials in the gas containing materials discharged from the dispersing dryer, and the remaining dust in the gas is collected by the bag filter, and the tail gas meets the emission standards. The cyclone II conducts gas-solid separation on the gas containing materials coming out of the green electric furnace, and the materials collected by the cyclone II enter the cyclone III. The materials in the cyclone III are mixed with the cooling gas to cool the materials and recover the heat of the materials. The collected materials are building gypsum products, and the temperature of the products is 110 - 120 °C, and the performance reaches that of similar products produced by fluidized bed boilers.

[0020] The dispersing dryer is a hammer-type dispersing dryer, designed and manufactured according to the structural principle of a hammer crusher. The materials and hot flue gas enter the dryer simultaneously, and the functions of dispersing and drying are achieved synchronously, having the characteristic of high production efficiency. After being dispersed and dried, the adsorbed water of the materials is reduced from 10 - 15% to 1 - 3%, making the materials in a loose state to obtain dry materials, which is beneficial for suspension calcination in the green electric furnace.

[0021] The elevator is a belt bucket elevator, with a working temperature of 100 - 150 °C, having the characteristics of stable operation and low equipment cost.

[0022] The screw conveyor is a kind of machine that uses an electric motor to drive a screw to rotate and push materials to move to achieve the purpose of conveying. It has the advantages of simple structure, small cross-sectional area, convenient operation, easy maintenance, and convenient for enclosed transportation.

[0023] The structure of the green electric furnace includes a furnace cover, a furnace body, and a furnace bottom. These three parts are connected by bolts, which is convenient for installation. The furnace cover and the furnace bottom are composed of high-aluminum cement refractory castable and a shell. The shell is made of carbon steel by welding, which has the characteristics of simple manufacturing and low cost.

[0024] The furnace body is a hollow cylinder. From the inner furnace chamber to the outside, there are a green electricity heating element, a heat insulation material, and a furnace body shell in sequence. The heat insulation material is one of mullite fiber and alumina fiber, both of which can achieve the purpose; it has the characteristics of light weight and high heat insulation efficiency, and the temperature of the furnace body shell is lower than 50 degrees. The furnace body shell is made of carbon steel, which has the characteristic of low cost.

[0025] The green electricity heating element is composed of a heating element, a protection tube, a mother board, and a cover board. The material of the heating element is one of iron-chromium-aluminum alloy and nickel-chromium alloy, which has the characteristics of oxidation resistance, corrosion resistance, and long service life, and both can achieve the invention purpose. The heating element is spiral and placed inside the protection tube. The working temperature of the heating element is 500 - 1100 °C.

[0026] The material of the protection tube is one of mullite and cordierite, which has the characteristics of low expansion coefficient and heat shock resistance, and both can achieve the invention purpose. The heating element is located in the protection tube. When the surface of the heating element is oxidized, blast furnace gas is introduced into the protection tube to reduce the oxide, realizing the regeneration of the heating element, extending its service life by 50 - 100%, and reducing costs.

[0027] The materials of the mother board, the cover board, and the T-shaped rod are all composite ceramics prepared by mixing and sintering silicon carbide (15 - 33%), silicon nitride (4 - 12%), zirconium silicate (20 - 50%), and quartz (10 - 15%). They have the characteristics of high strength, high temperature resistance, corrosion resistance, and anti-crust formation; the three-point bending strength of different formula composite ceramics can be greater than 800 MPa; the composite ceramics have good thermal shock resistance and can be water-cooled immediately after being heated to 750 °C for 20 cycles without damage. After the heating element is installed in the protection tube, it is placed in the cavity between the mother board and the cover board to prevent the furnace materials from contacting the protection tube and causing corrosion, extending the service life of the protection tube and the electric heating element, that is, providing two layers of protection for the electric heating element.

[0028] The mother board of the green electricity heating element is a cuboid with grooves at the front and back, which is built in the green electric furnace. The T-shaped head of the T-shaped rod is dovetail-shaped, and there is a round hole at the tail of the T-shaped rod. The material used for the T-shaped rod is the same as that of the mother board to avoid damage caused by different materials during operation. The T-shaped head of the T-shaped rod is placed in the T-shaped rod bonding groove on the furnace wall surface of the mother board, and the round hole at the tail of the T-shaped rod is hung on the metal hook on the inner wall of the furnace shell, so that the mother board is connected to the furnace shell and fixed in the furnace; the gap between the furnace wall surface of the mother board and the furnace shell is filled with heat-insulating material, and the surface temperature of the furnace wall is lower than 50°C; the heat-insulating material is one of mullite fiber and alumina fiber, both of which can achieve the purpose and have a service life of more than 10 years. The furnace hearth surface of the mother board is a dovetail groove, and the cover plate is dovetail-shaped, which is convenient for the installation, disassembly and maintenance of the protection tube and the electric heating element, and reduces the maintenance difficulty and cost.

[0029] The cover plate and the T-shaped rod are installed from the side of the mother board. The position that cannot be installed with the cover plate and the T-shaped rod left at the end of the installation is filled with castable. The dovetail design of the mother board, the cover plate and the T-shaped rod is convenient for installation and replacement and reduces the cost.

[0030] The green electric furnace uses green electricity as energy. During the process of the desulfurized gypsum undergoing a phase change to produce building gypsum, only water vapor is emitted. All the auxiliary equipment used in the production system uses green electricity, realizing zero carbon emissions in the production of building gypsum.

[0031] The cooling gas used in the cyclone III is part of the tail gas discharged by the induced draft fan. This tail gas is water vapor, which has a larger specific heat than air and a good cooling effect; the introduction amount of the tail gas is determined according to the temperature of the material, and the material is cooled to 110-120°C. Water vapor is beneficial to the conversion of anhydrite produced by overburning of industrial gypsum into hemihydrate gypsum and is beneficial to the stability of building gypsum products. The material, that is, the desulfurized gypsum, stays in this system for 5-18 seconds, less than 20 seconds, realizing the zero-carbon production of desulfurized building gypsum.

[0032] This system can also directly use the steam of the solar thermal power generation system as the heat source, which can realize the stable operation of the system; the inlet of the steam is the inlet of the dry material, that is, the steam and the dry material enter the green electric furnace together; the temperature of the steam is 300-600°C, and the products produced with steam as the heat source and green electricity as the heat source have the same performance. Description of the Drawings

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art; obviously, the drawings described below are only one embodiment recorded in the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0034] Figure 1It is a schematic diagram of a desulfurized building gypsum system for green electricity zero-carbon production provided by an embodiment of the present utility model.

[0035] Figure 2 It is a schematic diagram of the structure of a green electric furnace provided by an embodiment of the present utility model.

[0036] Figure 3 It is a schematic cross-sectional view of the structure of a green electricity heating element provided by an embodiment of the present utility model.

[0037] Reference numerals:

[0038] 101 - Chimney; 102 - Induced draft fan; 103 - Bag filter; 104 - High-temperature fan; 105 - Cyclone I; 106 - Disintegrating dryer; 107 - Cyclone II; 108 - Green electric furnace; 109 - Cyclone III; 110 - Elevator; 111 - Screw conveyor; 112 - Cooling air inlet; 113 - Dry material inlet; 114 - Material inlet; 115 - Product outlet; 116 - Tail gas outlet;

[0039] 201 - Furnace cover; 202 - Furnace body; 203 - Furnace bottom; 204 - Furnace cover shell; 205 - High-aluminum cement refractory castable; 206 - Furnace body shell; 207 - Thermal insulation material; 208 - T-shaped rod; 209 - Metal hook; 210 - Mother board; 211 - Furnace bottom shell; 212 - High-aluminum cement refractory castable; 213 - Gas inlet; 214 - Outlet;

[0040] 301 - Furnace hearth surface; 302 - Cover plate; 303 - Mother board; 304 - T-shaped rod bonding groove; 305 - Heating element; 306 - Furnace wall surface; 307 - Protection tube; 308 - T-shaped rod bonding groove; Detailed implementation manners

[0041] In order to enable those skilled in the art to better understand the present utility model, the present utility model will be further described below in conjunction with the accompanying drawings and embodiments. Obviously, the described embodiments are only one embodiment of the present utility model, rather than all embodiments. Without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other.

[0042] See Figure 1, A desulfurized building gypsum system for green power zero-carbon production provided by an embodiment of the present utility model includes a chimney, an induced draft fan, a bag filter, a high-temperature fan, cyclone I, a dispersing and drying machine, cyclone II, a green electric furnace, and cyclone III; characterized in that the chimney is connected to the outlet of the induced draft fan, the inlet of the induced draft fan is connected to the outlet of the bag filter, the inlet of the bag filter is connected to the outlet of the high-temperature fan, the inlet of the high-temperature fan is connected to the outlet of cyclone I, the inlet of cyclone I is connected to the outlet of the dispersing and drying machine, the inlet of the dispersing and drying machine is connected to the outlet of cyclone II, the inlet of cyclone II is connected to the outlet of the green electric furnace, and the inlet of the green electric furnace is connected to the outlet of cyclone III.

[0043] See Figure 1 , A desulfurized building gypsum system for green power zero-carbon production provided by an embodiment of the present utility model has the following working principle:

[0044] 1. Taking the gas flow direction as an example for illustration, where, Figure 1 the gas flow direction is represented by a dashed line in ; the cooling gas 112 enters cyclone III 109 to cool the material and is heated, and then the hot cooling gas enters the green electric furnace 108, mixes with the water vapor from gypsum dehydration, and then enters cyclone II 107, the dispersing and drying machine 106, cyclone I 105, the high-temperature fan 104, the bag filter 103, the induced draft fan 102 in sequence, and finally enters the chimney 101 and is discharged up to standard from the tail gas outlet 116.

[0045] 2. Taking the material flow direction of desulfurized gypsum as an example for illustration, where, Figure 1 the material flow direction is represented by a solid line in ; the material enters the connecting pipe between cyclone II 107 and the dispersing and drying machine 106 from the material inlet 114, enters the dispersing and drying machine together with the air flow, and after being dried and dispersed, enters cyclone I 105 and the bag filter 103 in sequence and is collected to obtain dry material; the dry material passes through the screw conveyor 111, and then enters the rising flue of cyclone III 109 from the dry material inlet 113 through the elevator 110, and then enters the green electric furnace 108; after being heated by the green electric furnace 108, the material enters cyclone II 107; after being collected by cyclone II 107, the material enters cyclone III 109 together with the cooling gas, and finally the material is collected by cyclone III 109 to obtain the desulfurized building gypsum product.

[0046] Taking desulfurized gypsum as the raw material, when the working temperatures of the green electric furnace using green power are 400, 600, 800, and 1000 °C respectively, the residence time of the material in this system is 10 seconds. According to the standard "Building Gypsum GB / T 9776", after the desulfurized building gypsum product is formed and cured, the flexural strength in the wet strength at 2 h is 3.8, 4.1, 4.5, and 3.4 MPa respectively, and the compressive strength is 6.7, 7.1, 9.2, and 6.3 MPa respectively.

[0047] Taking desulfurized gypsum as raw material, when the temperatures of the photothermal steam used in the green electric furnace are 300, 400, 500, and 600 °C respectively, the residence time of the material in this system is 10 seconds. According to the standard "Building Gypsum GB / T 9776", after the desulfurized building gypsum products are formed and cured, among the wet strengths after 2 hours, the flexural strengths are 3.7, 4.1, 4.4, and 3.5 MPa respectively, and the compressive strengths are 6.7, 7.2, 9.3, and 6.2 MPa respectively.

[0048] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A green electricity zero-carbon production desulfurized building gypsum system, comprising a chimney, an induced draft fan, a bag dust collector, a high-temperature fan, a cyclone I, a scattering dryer, a cyclone II, a green electric furnace, and a cyclone III; characterized in that: The chimney is connected with the outlet of the induced draft fan, the inlet of the induced draft fan is connected with the outlet of the bag dust collector, the inlet of the bag dust collector is connected with the outlet of the high-temperature fan, the inlet of the high-temperature fan is connected with the outlet of the cyclone I, the inlet of the cyclone I is connected with the outlet of the dispersion dryer, the inlet of the dispersion dryer is connected with the outlet of the cyclone II, the inlet of the cyclone III is connected with the outlet of the green electric furnace, and the inlet of the green electric furnace is connected with the outlet of the cyclone III; the green electric furnace consists of a furnace body, a furnace cover and a furnace bottom, and the furnace body includes a green electric heating element, a heat insulating material and a furnace body shell.

2. A green electricity zero-carbon production desulfurized building gypsum system according to claim 1, characterized in that: The electric energy used by the green electric furnace is one of photovoltaic power generation, wind power generation and solar thermal power generation.

3. A green electricity zero-carbon production desulfurized building gypsum system according to claim 1, characterized in that: The green electric heating element is composed of a heating element, a protective tube, a motherboard and a cover plate; wherein the material of the heating element is one of iron-chromium-aluminum alloy and nickel-chromium alloy, and the material of the protective tube is one of mullite and cordierite.

4. A green electricity zero-carbon production desulfurized building gypsum system according to claim 1, characterized in that: The heat insulating material is one of mullite fiber and alumina fiber.

5. A green electricity zero-carbon production desulfurized building gypsum system according to claim 1, characterized in that: The furnace cover and furnace bottom are composed of high-alumina cement refractory casting material and a shell.

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