Equipment for producing macrocrystalline fused magnesite by one-step method

Abstract

The utility model provides equipment for producing macrocrystalline fused magnesite by a one-step method, which comprises a drying tower, a fluidized bed furnace, a multi-stage settling chamber, a first dust remover, a hot powder surge bin, an electric melting furnace and a waste heat recovery chamber, the waste heat recovery chamber is respectively connected with the drying tower and the fluidized bed furnace, the drying tower conveys dried raw materials to the fluidized bed furnace, and the multi-stage settling chamber is connected with the first dust remover. Raw materials are preheated through the fluidized bed furnace, hot powder generated through preheating enters the multi-stage settling chamber along with hot-state smoke, the hot-state smoke is output to the first dust remover from the upper portion of the multi-stage settling chamber, and the hot powder enters the hot powder buffering bin from the bottom of the multi-stage settling chamber and is fed into the electric melting furnace connected with the hot powder buffering bin for high-temperature smelting; after smelting is finished, the electric melting furnace is transferred to a waste heat recovery chamber, and recovered heat is used for supplying heat to the drying tower and the fluidized bed furnace. The waste heat of the fused magnesium is fully utilized, the energy consumption is reduced, and the process is simple and easy to realize.

Description

TECHNICAL FIELD

[0001] The utility model relates to big crystal electric smelting magnesia production equipment especially to one -step method production big crystal electric smelting magnesia equipment. BACKGROUND

[0002] Big crystal electric smelting magnesia is a kind of high-quality high-grade refractory material, with high melting point, strong oxidation resistance and slag resistance, dense structure, chemical stability and other characteristics, is widely used in metallurgy, aerospace, nuclear industry and other fields. The existing big crystal electric smelting magnesia is mainly produced by two-step method, first, high-quality magnesite is calcined at 1100 DEG C, forming light-burned magnesia, then electric smelting is carried out in a submerged arc furnace, forming electric smelting magnesia, finally, big crystal electric smelting magnesia product is obtained. The problem in this production is long production process and large energy consumption.

[0003] Magnesite industry is a high energy consumption industry, and it consumes about 2700-3200 kWh of electricity per ton of magnesia product. In the electric smelting magnesia enterprise, the energy consumption of the electric smelting furnace accounts for more than 95% of the total energy consumption of the enterprise, and only about 40% of the energy is used for crystallization in the electric smelting process, and the rest of the energy is basically dissipated. In particular, after the smelting is completed, the furnace body is moved by rail for natural cooling, and the center temperature of the electric smelting magnesia is above 2800 DEG C, which needs to be naturally cooled for about 7 days, during which the electric smelting magnesia releases a large amount of sensible heat, which may account for more than 50% of the total energy consumption of electric smelting, so a large amount of heat energy is wasted. SUMMARY

[0004] The utility model provides a one -step method production big crystal electric smelting magnesia equipment, solve the problem of complex process flow, high energy consumption, make full use of the waste heat of electric smelting magnesia, can dry and preheat the magnesite flotation concentrate powder raw material, realize the production mode of efficient production and energy recycling. The specific technical scheme is as follows:

[0005] A one -step method production big crystal electric smelting magnesia equipment, including drying tower, boiling furnace, multistage settling chamber, first dust collector, hot powder buffer bin, electric smelting furnace and waste heat recovery room, the waste heat recovery room is connected with drying tower and boiling furnace respectively, the drying tower sends the dried raw material to the boiling furnace, the raw material is preheated in the boiling furnace, the hot powder generated by preheating enters the multistage settling chamber with hot flue gas, the hot flue gas is output from the upper part of the multistage settling chamber to the first dust collector, the hot powder enters the hot powder buffer bin from the bottom of the multistage settling chamber, is sent to the electric smelting furnace connected with the hot powder buffer bin and is smelted at high temperature, the electric smelting furnace after smelting is transferred to the waste heat recovery room, and the recovered heat is used for heating the drying tower and the boiling furnace.

[0006] The drying tower is used for drying raw materials, the upper material inlet is used for inputting raw materials, the flue gas outlet at the top is connected with the dust removal inlet of the second dust remover, and the material outlet at the bottom is used for outputting dried raw materials.

[0007] The material outlet at the bottom of the second dust remover is connected with the material inlet of the drying tower.

[0008] The material outlet of the drying tower is connected with the raw material buffer bin, the material outlet of the first dust remover is connected with the raw material buffer bin, hot powder in hot flue gas enters the raw material buffer bin through the material outlet at the bottom of the first dust remover, and the material outlet of the raw material buffer bin is connected with the fluidized bed furnace through a raw material feeder.

[0009] The upper portion of the fluidized bed furnace is provided with a material inlet, the top is provided with a flue gas outlet, the flue gas outlet is connected with the material inlet of the multi-stage settling chamber, and the bottom of the fluidized bed furnace is provided with a hot air chamber and connected with a waste heat recovery chamber.

[0010] The hot air chamber is connected with auxiliary heating equipment.

[0011] The multi-stage settling chamber is provided with at least one stage, the material inlet of a lower stage settling chamber is connected with the flue gas outlet of an upper stage settling chamber, the lower stage settling chamber is located above the upper stage settling chamber, the material inlet of the first stage settling chamber is connected with the fluidized bed furnace, the flue gas outlet of the last stage settling chamber is connected with the dust remover, and the material outlets at the bottoms of the settling chambers are connected with a hot powder buffer bin.

[0012] The material outlet of the hot powder buffer bin is connected with a hot powder feeder, and the other end of the hot powder feeder is connected with an electric smelting furnace.

[0013] The pipes connecting the fluidized bed furnace and the multi-stage settling chamber and the pipes connecting the multi-stage settling chamber and the preheating furnace are externally provided with heat preservation layers.

[0014] The one-step production large-crystal electric smelting magnesia equipment fully recovers and utilizes the waste heat of the electric smelting magnesia, hot air is used for drying and preheating raw materials, and hot powder is directly put into the electric smelting furnace, so that the heating energy consumption of the electric smelting furnace is reduced, and energy is saved. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a structural schematic view of the one-step production large-crystal electric smelting magnesia equipment. DETAILED DESCRIPTION

[0016] As Figure 1As shown, the one-step production of large crystalline fused magnesia equipment, including drying tower 1, fluidized bed furnace 5, multi-stage settling chamber 7, first dust collector 8, hot powder buffer bin 9, electric furnace 11 and waste heat recovery chamber 12, the waste heat recovery chamber 12 is connected with drying tower 1 and fluidized bed furnace 5 respectively, the drying tower 1 sends the dried raw materials to the fluidized bed furnace 5, the fluidized bed furnace 5 preheats the raw materials, the hot powder generated by preheating enters the multi-stage settling chamber 7 with hot flue gas, the hot flue gas is output from the upper part of the multi-stage settling chamber 7 to the first dust collector 8, the hot powder enters the hot powder buffer bin 9 from the bottom of the multi-stage settling chamber 7, is sent to the electric furnace 11 connected with the hot powder buffer bin 9 for high temperature smelting, the electric furnace 11 after smelting is transferred to the waste heat recovery chamber 12, and the recovered heat is used for heating the drying tower 1 and the fluidized bed furnace 5.

[0017] In the figure, the downward arrow represents the transfer process of solid raw materials, and the upward arrow represents the movement direction of hot flue gas. The material inlet of the drying tower 1 is connected with the elevator 13, and the raw materials to be preheated are sent in through the elevator 13, and the raw materials are magnesite flotation concentrate powder.

[0018] The drying tower 1 is used for drying the raw materials, the upper part is provided with a material inlet for inputting raw materials, the top is provided with a flue gas outlet connected with the dust inlet of the second dust collector 4, and the bottom is provided with a material outlet for conveying the dried raw materials to the fluidized bed furnace 5. Further, the material outlet at the bottom of the second dust collector 4 is connected to the material inlet of the drying tower 1. Further, the drying tower 1 and the fluidized bed furnace 5 are provided with a raw material buffer bin 2, which is connected with the fluidized bed furnace 5 through a raw material feeder 3, and the material is conveyed into the fluidized bed furnace 5 through the raw material feeder 3. Further, the material outlet of the first dust collector 8 is connected to the raw material buffer bin 2, and the hot powder entering the first dust collector 8 with hot flue gas enters the raw material buffer bin 2 through the material outlet at the bottom of the first dust collector 8.

[0019] The upper part of the fluidized bed furnace 5 is provided with a material inlet, the top is provided with a flue gas outlet, the flue gas outlet is connected with the material inlet of the multi-stage settling chamber 7, and the bottom of the fluidized bed furnace 5 is provided with a hot air chamber 6 for heating the raw materials preheated by the fluidized bed furnace. The hot air chamber 6 is connected with the waste heat recovery chamber 12 to receive the heat energy from the waste heat recovery chamber 12, and further is connected with the hot air outlet at the top of the waste heat recovery chamber. Considering that the hot air used in the fluidized bed furnace needs to be heated to about 1000℃, if the heat energy from the waste heat recovery chamber 12 is insufficient, the hot air chamber 6 is also connected with an auxiliary heating device 14, which can be used for auxiliary heating through the auxiliary heating device 14. Further, the fluidized bed furnace can be replaced by a suspension furnace, which is a kind of kiln that makes powder suspended in hot gas stream under the action of heat-carrying gas, and intense heat transfer and mass transfer process occurs between gas and solid.

[0020] The multi-stage settling chamber 7 is provided with at least one stage, and when more than two stages are provided, the heights of the different stages are different, the lowest stage is the first stage settling chamber, the material inlet of the first stage settling chamber is connected with the fluidized bed furnace, the flue gas outlet arranged at the top is connected with the material inlet of the next stage settling chamber, and the same is true for the subsequent stages. The material outlet at the bottom of the first stage settling chamber is connected with the hot powder buffer bin 9, and the flue gas outlet at the top of the last stage settling chamber is connected with the dust removal inlet of the first dust remover 8. The material outlets at the bottoms of the respective settling chambers are connected with the hot powder buffer bin 9. Part of the hot powder will enter the first dust remover 8 along with the hot flue gas, and after being collected, will also enter the raw material buffer bin 2 and finally enter the fluidized bed furnace 5.

[0021] The material outlet of the hot powder buffer bin 9 is connected with the hot powder feeder 10, and the other end of the hot powder feeder 10 is connected with the electric smelting furnace 11. The hot powder feeder 10 is used to convey the material to the electric smelting furnace 11 to prepare large-crystal electric smelting magnesia. The electric smelting furnace 11 is used to smelt large-crystal electric smelting magnesia, and after smelting, the electric smelting furnace 11 enters the waste heat recovery chamber 12.

[0022] The utility model is suitable for one-step preparation of large-crystal electric smelting magnesia process, solves the problems of complex process flow and high energy consumption, fully utilizes the waste heat of the electric smelting magnesia, dries and preheats the magnesite flotation concentrate powder raw material, realizes efficient production and energy recycling. The equipment in the utility model is easy to realize and operate, and is suitable for application and promotion.

Claims

1. A one-step process for producing large-crystal fused magnesia, characterized in that: The system includes a drying tower, a fluidized bed furnace, a multi-stage settling chamber, a first dust collector, a hot powder buffer chamber, an electric furnace, and a waste heat recovery chamber. The waste heat recovery chamber is connected to both the drying tower and the fluidized bed furnace. The drying tower feeds the dried raw material into the fluidized bed furnace, which preheats the raw material. The hot powder generated during preheating enters the multi-stage settling chamber along with the hot flue gas. The hot flue gas exits from the top of the multi-stage settling chamber to the first dust collector. The hot powder enters the hot powder buffer chamber from the bottom of the multi-stage settling chamber and is then fed into the electric furnace connected to the hot powder buffer chamber for high-temperature smelting. After smelting, the electric furnace is transferred to the waste heat recovery chamber, where the recovered heat is used to heat the drying tower and the fluidized bed furnace.

2. The equipment for one-step production of large-crystal fused magnesia according to claim 1, characterized in that: The drying tower is used to dry raw materials. The upper material inlet is used to input raw materials, the top flue gas outlet is connected to the dust removal inlet of the second dust collector, and the bottom material outlet is used to output the dried raw materials.

3. The equipment for one-step production of large-crystal fused magnesia according to claim 2, characterized in that: The material outlet at the bottom of the second dust collector is connected to the material inlet of the drying tower.

4. The equipment for one-step production of large-crystal fused magnesia according to claim 1, characterized in that: The material outlet of the drying tower is connected to the raw material buffer silo, and the material outlet of the first dust collector is also connected to the raw material buffer silo. As hot flue gas enters the hot powder of the first dust collector, it enters the raw material buffer silo through the material outlet at the bottom of the first dust collector. The material outlet of the raw material buffer silo is connected to the fluidized bed furnace through a raw material feeder.

5. The equipment for one-step production of large-crystal fused magnesia according to claim 1, characterized in that: The fluidized bed furnace has a material inlet at the top and a flue gas outlet at the top, which is connected to the material inlet of the multi-stage settling chamber. The bottom of the fluidized bed furnace has a hot air chamber connected to the waste heat recovery chamber.

6. The equipment for one-step production of large-crystal fused magnesia according to claim 5, characterized in that: The hot air chamber is connected to auxiliary heating equipment.

7. The equipment for one-step production of large-crystal fused magnesia according to claim 1, characterized in that: The multi-stage settling chamber is provided with at least one stage. The material inlet of the lower stage settling chamber is connected to the flue gas outlet of the upper stage settling chamber. The lower stage settling chamber is located above the upper stage settling chamber. The material inlet of the first stage settling chamber is connected to the fluidized bed furnace. The flue gas outlet of the last stage settling chamber is connected to the dust collector. The material outlet at the bottom of each settling chamber is connected to the hot powder buffer silo.

8. The equipment for one-step production of large-crystal fused magnesia according to claim 1, characterized in that: The material outlet of the hot powder buffer silo is connected to the hot powder feeder, and the other end of the hot powder feeder is connected to the electric furnace.

9. The equipment for one-step production of large-crystal fused magnesia according to claim 1, characterized in that: The pipes connecting the fluidized bed furnace to the multi-stage settling chamber and the pipes connecting the multi-stage settling chamber to the preheating furnace are all equipped with insulation layers.

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