US-12618118-B2 - High efficiency processing method and plant for multiphase steel slag

Abstract

The disclosure provides a high efficiency processing method and plant for multiphase steel slag. The plant comprises a steel slag feeding equipment and a rotary drum for processing steel slag. The feeding equipment comprises a feeding chute; the processing plant further comprises a storage bin is provided between the feeding chute and the rotary drum, the storage bin is in a shape of barrel, with one end forming a rotatable fit with a lower opening end of the chute with a funnel, the other end being connected with a processing chamber of the rotary drum and coaxial with the rotary drum. With the storage bin that is inclined and provided between the front of the rotary drum and the feeding chute, working as buffer transition section, the safe rotary drum processing for each type of steel slag can be achieved without using the slag removal equipment.

Inventors

• Yongli Xiao
• Yongqian Li

Assignees

• BAOSHAN IRON & STEEL CO., LTD.

Dates

Publication Date

20260505

Application Date

20210329

Priority Date

20200506

Claims (9)

1. 1 . A processing plant for multiphase steel slag, comprising a steel slag feeding equipment and a rotary drum for processing steel slag, wherein the steel slag feeding equipment comprises a feeding chute; the processing plant for multiphase steel slag further comprises a storage bin is provided between the feeding chute and the rotary drum, the storage bin is with a shape of barrel, with one end forming a rotatable fit with a lower opening end of the chute with a funnel, the other end being connected with a processing chamber of the rotary drum and coaxial with the rotary drum; a slag discharging area of an outer cylinder of a rotary drum is provided with water collecting rooms configured as a waterwheel to ensure no accumulation of water during processing, and the rooms are provided evenly along the circumference of the outer cylinder, an angle of a partition plate between two adjacent water collecting rooms matches with an opening angle of the funnel for receiving slag.
2. 2 . The processing plant for multiphase steel slag according to claim 1 , wherein the lower opening end of the chute forms a clearance fit with an opening end of the storage bin.
3. 3 . The processing plant for multiphase steel slag according to claim 1 , wherein an axis of the rotary drum has an angle of inclination relative to a horizontal plane, where the angle of inclination ranges from 0° to 25°.
4. 4 . The processing plant for multiphase steel slag according to claim 1 , wherein an axis of the rotary drum has an angle of inclination relative to a horizontal plane, where the angle of inclination ranges from 8° to 12°.
5. 5 . The processing plant for multiphase steel slag according to claim 1 , wherein the inner wall of the storage bin is water cooling wall.
6. 6 . The processing plant for multiphase steel slag according to claim 1 , wherein annular cooling spray tubes are provided, the spray tubes are provided evenly along an axis of the storage bin, an outer cover is provided outside the cooling tubes, the outer cover is fixed with ground and discharges spraying water collected from the cooling tubes, the cooling tubes are fixed on the cover.
7. 7 . The processing plant for multiphase steel slag according to claim 1 , wherein a lower portion of the feeding chute withstanding flow of hot slag is provided with a water cooling equipment.
8. 8 . The processing plant for multiphase steel slag according to claim 1 , wherein a volume of the storage bin is 2-3 times a volume of a slag tank.
9. 9 . The processing plant for multiphase steel slag according to claim 1 , wherein the lower opening end of the feeding chute is inserted into the end of the storage bin.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a 371 U.S. National Phase of PCT International Application No. PCT/CN2021/083672 filed on Mar. 29, 2021, which claims benefit and priority to Chinese patent application No. CN202010373411.0 filed on May 6, 2020, the contents of each of the above listed applications are incorporated by reference herein in their entiries. TECHNICAL FIELD The disclosure relates to a metallurgical slag processing method and plant, in particular to a high efficiency processing method and plant for multiphase high temperature steel slag by a rotary drum processing. BACKGROUND Steel slag is one of the bulk by-products produced during the steel production process, accounting for about 10-30% of crude steel production; steel slag is mainly composed of calcium, magnesium, silicon, aluminum, iron and other metal oxides, phosphorus, sulfur non-metallic oxides and the complex mixture composed of various polymers with high melting point, and is also doped with 1-10% metallic iron with different particle sizes; the temperature of the steel slag just discharged from the furnace is about 1500° C., most of the steel slag is at a molten state with fluidity, however with the decrease of the temperature, the viscosity of the steel slag increases rapidly, releasing a lot of heat. Due to the difference in the steelmaking process of each steel plant, the composition and temperature of the steel slag produced during the steelmaking process are different: some of the high temperature steel slag has high fluidity, which can be poured like water; some of the slag has poor fluidity, which is difficult to be poured from the slag tank (the container for holding and conveying the high temperature steel slag, also known as slag bag), and can only be removed from the slag tank with the assistant of external mechanical force or by inverting the slag tank; in order to extend the service life of the slag tank and prevent the high temperature steel slag from scouring the bottom of the slag tank when the slag is poured therein, it is necessary to put some cold slag on the bottom of the empty slag tank when receiving slag from the converter furnace, so that when pouring the high temperature steel slag, these cold slag will be mixed and molten with the high temperature steel slag, forming into large slag lumps together with the steel slag on the inner wall of the slag tank, which are several tons or more than ten tons, accounting for about one-fourth to one-half of the total slag amount, this part of slag is also called the slag at the bottom of the tank. The complexity of the composition and the diversity of morphology of steel slag bring great difficulties to the processing and subsequent utilization of steel slag. The most common steel slag processing techniques are hot pouring and post-processing, where the high temperature steel slag is poured into the slag processing place for natural cooling, and then the cooled steel slag is subjected to crushing, magnetic separating and classification screening, the cold steel recovered is returned to the production process for utilization, and the tailings after separation are reused or sold socially according to particle size and performance. The steel slag can be attributed to silicate material, which has poor thermal conductivity and extremely low natural cooling rate. In order to improve the cooling processing efficiency of steel slag and reduce the area of the cooling processing place, mechanical turning over, spraying cooling water and other actions are often taken in the slag processing workshop, resulting in the diffusion of dust and waste steam and harsh working environment where the dust in the surrounding environment exceeds the standard seriously and there is a risk of explosion if not careful. Nowadays the environmental protection requirement is more strict, the short-process, fast, safe and environmentally friendly high temperature steel slag processing technique has become the focus of steel enterprises to explore urgently. The steel slag processing technique by the drum method developed by an steel enterprise rises in response to such background, which is an airtight, fast and resourceful novel technique for steel slag hot processing, achieving the function of dynamical, continuously and rapid cooling of the high temperature metallurgical slag and crushing the slag into granular product slag with a particle diameter of less than 50 mm in the airtight equipment, where the exhaust gas generated during the process is collected by the gas duct and discharged through the chimney up to the standard after the purifying processing, so the current situation of disorderly discharge in other processing technique is completely changed, and the recycle of sewage and zero discharge is achieved. The process not only is a short process with a low cost, but also is easy to operate, safe and reliable, the steel slag after processing can be used directly as a resou