CN-116855648-B - Device and method for modifying steel slag and recovering valuable elements

CN116855648BCN 116855648 BCN116855648 BCN 116855648BCN-116855648-B

Abstract

The invention discloses a device and a method for modifying steel slag and recovering valuable elements, and belongs to the technical field of solid waste treatment in the metallurgical industry. The steel slag modification and valuable element recovery device comprises a rotary tilting system and a spray gun system, wherein the rotary tilting system comprises a modification reducing furnace and a tilting frame, the modification reducing furnace is arranged in the tilting frame and can rotate in the tilting frame by taking a furnace body central shaft as an axis and tilt by taking a tilting shaft of the tilting frame as an axis, the spray gun system comprises a powder spraying heat supplementing gun and a rotary lifting mechanism, the powder spraying heat supplementing gun is arranged on the upper side of a charging furnace opening at the top of the modification reducing furnace, one end of the rotary lifting mechanism is connected with the powder spraying heat supplementing gun, and the other end of the rotary lifting mechanism is connected with one side of the tilting shaft. The device and the method provided by the invention effectively improve the stirring dynamics condition in the modification and reduction process, and utilize the powder spraying and heat supplementing gun to heat, modify and carbothermic reduction the slag, thereby realizing the recovery of valuable elements such as phosphorus, iron, manganese and the like in the steel slag.

Inventors

HE SAI
LIN LU
HOU ZHONGXIAO
HU YANBIN
HUANG FANG
JIA ZHILI

Assignees

钢铁研究总院有限公司

Dates

Publication Date: 20260508
Application Date: 20230719

Claims (6)

1. The device for modifying steel slag and recovering valuable elements is characterized by comprising a rotary tilting system and a spray gun system, wherein, The rotary tilting system comprises a modification reducing furnace and a tilting frame, wherein the modification reducing furnace is arranged in the tilting frame, and the modification reducing furnace can rotate in the tilting frame by taking a furnace body central shaft as an axis and tilt by taking a tilting shaft of the tilting frame as an axis; The modification reducing furnace is connected in the tilting frame through a rotary support arranged at the inner side of the tilting frame, and can rotate 360 degrees by taking a Y axis as an axis under the support drive of the rotary support; The spray gun system comprises a powder spraying and heat supplementing gun and a rotary lifting mechanism, wherein the powder spraying and heat supplementing gun is arranged on the upper side of a charging furnace opening at the top of the modification reduction furnace, one end of the rotary lifting mechanism is connected with the powder spraying and heat supplementing gun, and the other end of the rotary lifting mechanism is connected with one side of the tilting shaft; the powder spraying and heat supplementing gun comprises a first pipeline, a second pipeline, a third pipeline and a combustion-supporting gas pipeline, wherein the first pipeline is a powder adding pipeline, the second pipeline surrounds the first pipeline and is a gas pipeline, and the third pipeline surrounds the second pipeline and is a combustion-supporting gas pipeline; The powder is added into the powder spraying and supplementing heat gun to carry out modification and reduction on steel slag in the modification and reduction process, the main function of fuel gas is to carry out heating and temperature supplementing on the steel slag, the powder spraying and supplementing heat gun is designed at a high speed, and the jet outlet speed is more than 80m/s; The rotary lifting mechanism includes: One end of the lifting cross arm is connected with the powder spraying heat supplementing gun, and the other end of the lifting cross arm is connected with the guide mechanism; one end of the upright post is connected with the guide mechanism, and the other end of the upright post is provided with a rotating shaft hole which is rotatably connected with the tilting shaft of the tilting frame; the tapping mechanism comprises: the brick cup is arranged at the bottom of the modification reducing furnace in a penetrating way, and a steel tapping hole is arranged in the middle of the brick cup; the first sliding plate is arranged on the lower side of the brick cup and is in sliding connection with the bottom of the modification reducing furnace, and a first through hole is formed in the left side of the first sliding plate; The second slide is arranged on the lower side of the first slide and is in sliding connection with the first slide, a second through hole is arranged on the left side of the second slide, a third through hole is arranged in the middle of the second slide, and a sand filling device is arranged on the lower side of the second through hole.
2. The device of claim 1, wherein the rotary lifting mechanism further comprises a chain, the chain is arranged on the upright post, two ends of the chain are respectively connected with the guide mechanism, meanwhile, a chain wheel is arranged on the upper side and the lower side of the upright post, and the chain is sleeved on the chain wheel.
3. The device according to claim 2, wherein the side of the upright is provided with a pinch roller and a driving roller, and the chain is sleeved on the pinch roller and the driving roller.
4. The apparatus of claim 1, wherein the sand filling apparatus comprises: the longitudinal extrusion device is arranged at the lower side of the second through hole and is communicated with the second through hole; And one end of the transverse extrusion device is communicated with the longitudinal extrusion device, the upper side of the other end of the transverse extrusion device is provided with a sand storage bin, and the sand storage bin is communicated with the transverse extrusion device.
5. The apparatus of claim 1, wherein the first through hole is a tap hole when communicating with the third through hole and the tap hole of the brick cup, and wherein the first through hole is a sand filling hole when communicating with the second through hole.
6. A method for modifying steel slag and recovering valuable elements, which is characterized by adopting the device as claimed in any one of claims 1-5 and comprising the following steps: After tapping of the primary smelting furnace, adding a modifier into the bottom of the modification reducing furnace or along with liquid slag flow in advance in the slag pouring process of high-temperature steel slag, and carrying out melting modification treatment on the slag by utilizing the waste heat of the steel slag and slag discharging power; step 2, after the modified thermal slag obtained in the step 1 is poured into a modified reduction furnace on line, gas is blown into the mouth of the modified reduction furnace, the temperature of the slag is supplemented, and meanwhile, the slag in a molten pool is stirred; Step 3, after the temperature of the slag is raised in the modified reduction furnace, blowing a reducing agent into the modified slag at the mouth of the modified reduction furnace; and 4, after the reduction is finished, the molten slag pool is calmed, slag and molten metal are layered, then molten metal is discharged from the bottom of the modified reduction furnace, and slag is discharged from a turnover furnace opening.

Description

Device and method for modifying steel slag and recovering valuable elements Technical Field The invention belongs to the technical field of solid waste treatment in metallurgical industry, and particularly relates to a device and a method for modifying steel slag and recovering valuable elements. Background The steel yield in China is large and reaches 10.32 hundred million tons in 2021, the produced steel slag amount exceeds 1 hundred million tons, and due to the fact that a certain amount of valuable elements such as phosphorus, iron and the like exist in the steel slag, the valuable elements cannot be effectively separated and recovered through a physical method, many expert students also propose to reduce iron oxides in the slag to form molten iron through a carbothermic reduction method, so that the iron liquid can be effectively separated and recovered, the reduced phosphorus can enter the molten iron in the reduction process, and therefore effective recycling of phosphorus-iron resources in the slag can be achieved, on the other hand, due to the fact that the slag alkalinity is high, recycling of the slag is limited, many researchers propose to add substances such as quartz sand mainly including SiO 2 after slag is discharged, the alkalinity of the slag can be effectively reduced, the utilization way of the slag can be increased, and especially the low-alkalinity steel slag can be greatly used in materials. Based on the two backgrounds, a lot of research works at the present stage add carbon powder as a reducing agent and a modifier taking SiO 2 as a main component in the slag discharging process of a converter, and simultaneously achieve the purposes of recovering valuable element resources such as ferrophosphorus and the like by reducing the steel slag and increasing the utilization way of the steel slag, however, in the process, the dynamics condition is poor between the steel slag, the carbon powder and the modifier, the temperature compensating condition is poor, valuable elements such as ferrophosphorus and the like in the slag cannot be reduced with high efficiency, meanwhile, the modified steel slag is uneven, the content of free calcium oxide in the steel slag still cannot meet the requirements of building materials, and based on the background, the invention needs to provide a device capable of simultaneously carrying out modification reduction on the steel slag, carrying out modification reduction treatment on the steel slag, improving the dynamics condition and the temperature compensating condition, and achieving the purposes of high-efficiency reduction and modification of the steel slag. Disclosure of Invention In view of the above analysis, the present invention aims to provide a device and a method for modifying steel slag and recovering valuable elements, which are used for solving at least one of the problems of poor dynamic conditions and poor temperature compensation conditions in the existing modification and reduction process. The aim of the invention is mainly realized by the following technical scheme: The invention provides a steel slag modification and valuable element recovery device which comprises a rotary tilting system and a spray gun system, wherein the rotary tilting system comprises a modification reduction furnace and a tilting frame, the modification reduction furnace is arranged in the tilting frame and can rotate in the tilting frame by taking a furnace body central shaft as an axis and tilt by taking a tilting shaft of the tilting frame as an axis, the spray gun system comprises a powder spraying heat supplementing gun and a rotary lifting mechanism, the powder spraying heat supplementing gun is arranged on the upper side of a charging furnace mouth at the top of the modification reduction furnace, one end of the rotary lifting mechanism is connected with the powder spraying heat supplementing gun, and the other end of the rotary lifting mechanism is connected with one side of the tilting shaft. Preferably, the powder injection heat supplementing gun comprises: the first pipeline is a powder adding pipeline, A second pipeline surrounding the first pipeline and being a gas pipeline, And the third pipeline surrounds the second pipeline and is a fuel gas pipeline. Preferably, the reforming reduction furnace is connected to the inside of the tilting frame via a rotary support provided inside of the tilting frame. Preferably, the rotation lifting mechanism includes: One end of the lifting cross arm is connected with the powder spraying heat supplementing gun, and the other end of the lifting cross arm is connected with the guide mechanism; and one end of the upright post is connected with the guide mechanism, and the other end of the upright post is provided with a rotating shaft hole which is rotatably connected with the tilting shaft of the tilting frame. Preferably, the rotary lifting mechanism further comprises a chain, the chain is arranged on the upright post,