A method for preparing stainless steel dust ash sintered ore

Abstract

The invention discloses a method for preparing stainless steel dust ash sintered ore, and relates to the technical field of iron ore sintering. The method comprises the steps of digestion and wetting, batching, mixing and granulation, sintering and cooling. When wetting, water is added to the stainless steel dust ash in an anti-leakage tank at a ratio of 3:1, and the calcium oxide is digested and mixed until the water content is within 15%. The batching is mainly 80% of the stainless steel dust ash, and the stainless steel dust ash originally treated as waste is transformed into treasure by combining with iron concentrate, sintering return ore, etc., and is re-incorporated into the production circulation system, thereby greatly improving the recycling rate of internal resources of steel enterprises and reducing dependence on external primary resources such as iron concentrate. The stainless steel dust ash sintered ore has significant advantages, and the iron material is taken from the dust ash produced by the steel enterprise itself. Compared with conventional iron concentrate sintering production, the concentrate consumption cost can be reduced by about 360 yuan / t, and the comprehensive cost of sintered ore can be reduced by 280 yuan / t.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgy, and in particular to a method for preparing stainless steel dust ash sintered ore. Background Art

[0002] The dust produced during the stainless steel production process contains a large amount of toxic heavy metal elements such as chromium and nickel, which is a hazardous solid waste. If not handled in time, it will cause environmental pollution and have a toxic effect on the human body and the surrounding environment, especially Cr 6+ It is extremely toxic and can be absorbed through breathing, diet and skin. At the same time, precious metal resources such as chromium and nickel cannot be utilized. Traditional treatment methods often have defects such as complex processes, high costs and low resource utilization, which are difficult to meet the needs of modern steel enterprises for green and efficient development. Summary of the invention

[0003] In view of the above technical problems, the present invention provides a method for preparing stainless steel dust ash sintered ore, which is used to solve the problems of high cost and low resource utilization rate of existing stainless steel dust ash treatment methods.

[0004] In order to achieve the above object, the technical solution of the present invention is as follows: A method for preparing stainless steel dust ash sintered ore, comprising the following steps: S1, digestion and wetting, add stainless steel dust ash into the anti-leakage tank, then add water, the ratio of stainless steel dust ash to water is 3:1, after the calcium oxide in the stainless steel dust ash is digested, mix the stainless steel dust ash evenly; S2, ingredients, the ingredients structure is stainless steel dust ash accounts for 80%, iron ore accounts for 5.0%, stainless steel dust ash sintering return ore accounts for 3.0%, quicklime accounts for 3.0%, limestone accounts for 4.0%, and fuel accounts for 5.0%; S3, mixing and granulating, adding the prepared materials into the mixer for primary mixing and secondary granulation; S4, sintering, transporting the granulated mixture to the sintering machine for sintering, the thickness of the sintering machine material layer is 500-700mm, of which the thickness of the bottom material is 50-60mm, the temperature of the mixture is 40-50℃, and the main pipe temperature of the sintering machine is 120-140℃; S5, cooling, the mixture is sintered to form stainless steel dust ash sintered ore, and the stainless steel dust ash sintered ore enters the ring cooler to be cooled to room temperature, wherein the thickness of the stainless steel dust ash sintered ore layer in the ring cooler is 1000-1050mm.

[0005] Furthermore, after step S1, the moisture content in the stainless steel dust ash is within 15%.

[0006] Furthermore, after step S3, the moisture content of the granulated mixture is 8.9%-9.5%.

[0007] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention transforms stainless steel dust ash, which was originally treated as waste, into treasure and reincorporates it into the production cycle system, greatly improving the recycling rate of internal resources of steel enterprises and reducing dependence on external primary resources such as iron ore concentrate. In addition, the stainless steel dust ash sintered ore has significant advantages. The iron material is taken from the enterprise's own dust ash. Compared with conventional iron ore sintering production, it can reduce the concentrate consumption cost by about 360 yuan / t, and the comprehensive cost of sintered ore can be reduced by 280 yuan / t. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0009] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0010] Embodiment 1, A method for preparing stainless steel dust ash sintered ore, comprising the following steps: S1. Digestion and wetting: add stainless steel dust ash to the anti-leakage tank, then add water, the ratio of stainless steel dust ash to water is 3:1, after the calcium oxide in the stainless steel dust ash is digested, mix the stainless steel dust ash evenly, and the water content of the stainless steel dust ash after mixing is 13%; S2, ingredients, the ingredients are stainless steel dust ash accounting for 80%, iron ore accounting for 5.0%, stainless steel dust ash sintering return ore accounting for 3.0%, quicklime accounting for 3.0%, limestone accounting for 4.0%, and fuel accounting for 5.0%; S3, mixing and granulation, adding the ingredients into the mixer for primary mixing and secondary granulation, the moisture content of the mixture after granulation is 8.9%; S4, sintering, transporting the granulated mixed material to the sintering machine for sintering, the sintering machine material layer thickness is 500mm, of which the base material thickness is 50mm, the mixed material temperature is 40℃, and the main pipe temperature of the sintering machine is 120℃; S5, cooling: the mixture is sintered to form stainless steel dust ash sintered ore, and the stainless steel dust ash sintered ore enters the ring cooler to be cooled to room temperature, wherein the thickness of the stainless steel dust ash sintered ore layer in the ring cooler is 1000mm.

[0011] Embodiment 2, A method for preparing stainless steel dust ash sintered ore, comprising the following steps: S1. Digestion and wetting: add stainless steel dust ash to the anti-leakage tank, then add water, the ratio of stainless steel dust ash to water is 3:1, after the calcium oxide in the stainless steel dust ash is digested, mix the stainless steel dust ash evenly, and the water content of the stainless steel dust ash after mixing is 14%; S2, ingredients, the ingredients are stainless steel dust ash accounting for 80%, iron ore accounting for 5.0%, stainless steel dust ash sintering return ore accounting for 3.0%, quicklime accounting for 3.0%, limestone accounting for 4.0%, and fuel accounting for 5.0%; S3, mixing and granulation, adding the ingredients into the mixer for primary mixing and secondary granulation, the moisture content of the mixture after granulation is 9.2%; S4, sintering, transporting the granulated mixed material to the sintering machine for sintering, the sintering machine material layer thickness is 600mm, of which the base material thickness is 55mm, the mixed material temperature is 45°C, and the main pipe temperature of the sintering machine is 130°C; S5, cooling, the mixture is sintered to form stainless steel dust ash sintered ore, and the stainless steel dust ash sintered ore enters the ring cooler to be cooled to room temperature, wherein the thickness of the stainless steel dust ash sintered ore layer in the ring cooler is 1025mm.

[0012] Embodiment 3, A method for preparing stainless steel dust ash sintered ore, comprising the following steps: S1. Digestion and wetting: add stainless steel dust ash to the anti-leakage tank, then add water, the ratio of stainless steel dust ash to water is 3:1, after the calcium oxide in the stainless steel dust ash is digested, mix the stainless steel dust ash evenly, and the water content of the stainless steel dust ash after mixing is 14.5%; S2, ingredients, the ingredients are stainless steel dust ash accounting for 80%, iron ore accounting for 5.0%, stainless steel dust ash sintering return ore accounting for 3.0%, quicklime accounting for 3.0%, limestone accounting for 4.0%, and fuel accounting for 5.0%; S3, mixing and granulating, adding the ingredients into the mixer for primary mixing and secondary granulation, the moisture content of the mixture after granulation is 9.5%; S4, sintering, transporting the granulated mixed material to the sintering machine for sintering, the sintering machine material layer thickness is 700mm, of which the base material thickness is 60mm, the mixed material temperature is -50℃, and the main pipe temperature of the sintering machine is 140℃; S5, cooling: the mixture is sintered to form stainless steel dust ash sintered ore, and the stainless steel dust ash sintered ore enters the ring cooler to be cooled to room temperature, wherein the thickness of the stainless steel dust ash sintered ore layer in the ring cooler is 1050mm.

[0013] The production cost of ordinary sintered ore consists of: The production cost of ordinary sintered ore covers many aspects, including: Iron materials: such as iron ore concentrate, sintered ore, etc., are the main raw material inputs.

[0014] Fuel: coke powder, lignite, etc., used to provide the heat required for sintering.

[0015] Flux: Such as limestone, quicklime, etc., plays the role of fluxing and slag forming.

[0016] Power energy: including water, electricity, gas, etc., to ensure the energy supply of the production process.

[0017] Labor cost: the cost expenditure corresponding to human labor.

[0018] Cost advantages of stainless steel dust ash sintering: The cost of iron materials has dropped sharply: The iron source of stainless steel dust ash sintered ore is the stainless steel dust ash produced by the steel enterprises in the production process, and its material acquisition cost is extremely low. Compared with conventional iron materials, only about 10 yuan / t of cost is generated in the vehicle or belt transportation link, and other costs such as procurement are almost negligible.

[0019] According to the calculation that the unit consumption of iron material in sintered ore production is about 0.9 / t sintered ore, and with reference to the current market price of iron concentrate of about 400 yuan / t, using stainless steel dust ash as iron material can reduce the concentrate consumption cost by about 400 yuan / t×0.9 (concentrate unit consumption) = 360 yuan / t.

[0020] The overall cost is significantly reduced: The TFe (total iron content) of stainless steel dust ash sintered ore is about 20% lower than that of ordinary sintered ore, and the TFe acquisition rate is calculated at 80%.

[0021] Comprehensive calculation shows that the cost of stainless steel dust ash production can be reduced compared with ordinary sintered ore production: [360 yuan (iron material cost) - 10 yuan (transportation cost)] × 80% = 280 yuan / t.

[0022] The stainless steel dust ash that was originally treated as waste is turned into treasure and reincorporated into the production cycle system, which greatly improves the recycling rate of internal resources of steel enterprises and reduces dependence on external primary resources such as iron ore concentrate.

[0023] From the perspective of resource utilization and sustainable development, the present invention is of great significance. It turns stainless steel dust, which was originally treated as waste, into valuables and re-incorporates it into the production cycle system, greatly improving the recycling rate of internal resources of steel enterprises and reducing dependence on external primary resources such as iron ore concentrate. It is in line with the current trend of green and low-carbon development and opens up a new path for the sustainable development of the steel industry.

[0024] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing stainless steel dust ash sintered ore, characterized in that: The following steps are involved: S1, digestion and wetting, add stainless steel dust ash into the anti-leakage tank, then add water, the ratio of stainless steel dust ash to water is 3:1, after the calcium oxide in the stainless steel dust ash is digested, mix the stainless steel dust ash evenly; S2, ingredients, the ingredients structure is stainless steel dust ash accounts for 80%, iron ore accounts for 5.0%, stainless steel dust ash sintering return ore accounts for 3.0%, quicklime accounts for 3.0%, limestone accounts for 4.0%, and fuel accounts for 5.0%; S3, mixing and granulating, adding the prepared materials into the mixer for primary mixing and secondary granulation; S4, sintering, transporting the granulated mixture to the sintering machine for sintering, the thickness of the sintering machine material layer is 500-700mm, of which the thickness of the bottom material is 50-60mm, the temperature of the mixture is 40-50℃, and the main pipe temperature of the sintering machine is 120-140℃; S5, cooling, the mixture is sintered to form stainless steel dust ash sintered ore, and the stainless steel dust ash sintered ore enters the ring cooler to be cooled to room temperature, wherein the thickness of the stainless steel dust ash sintered ore layer in the ring cooler is 1000-1050mm.

2. The method for preparing stainless steel dust ash sinter according to claim 1, characterized in that: After step S1, the moisture content in the stainless steel dust is within 15%.

3. The method for preparing stainless steel dust ash sintered ore according to claim 1, characterized in that: After step S3, the moisture content of the granulated mixture is 8.9%-9.5%.

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