CN107651857B

CN107651857B - Process for quickly dissolving silica sand and bauxite in slag liquid

Info

Publication number: CN107651857B
Application number: CN201710802905.4A
Authority: CN
Inventors: 孙金波; 薛丹宏; 赵鹏伟; 王钢; 王军; 武一泉; 薛惠临; 王艳军; 李鹏
Original assignee: Shanxi Taigang Stainless Steel Co Ltd
Current assignee: Shanxi Taigang Stainless Steel Co Ltd
Priority date: 2017-09-08
Filing date: 2017-09-08
Publication date: 2020-06-26
Anticipated expiration: 2037-09-08
Also published as: CN107651857A

Abstract

The invention discloses a process for quickly dissolving silica sand and bauxite in slag liquid, which comprises the following steps: inserting a nitrogen pipeline into the hot slag through a furnace cover, inserting the nitrogen pipeline into the position 200-500cm below the surface of the high-temperature slag, and adjusting the flow corresponding to the nitrogen according to the difference of the liquid level of the slag in the furnace and the insertion depth to stir the slag liquid, the silica sand and the bauxite so as to realize the rapid dissolution of the silica sand and the bauxite in the slag liquid; the nitrogen pressure is kept between 0.5 and 0.6MPa, and the adopted nitrogen pipeline is made of hollow carbon rod materials. The nitrogen stirring is adopted, so that the requirements of fast-paced mass production and uniform and stable components are met, and the unit power consumption is reduced.

Description

Process for quickly dissolving silica sand and bauxite in slag liquid

Technical Field

The invention relates to a process for quickly dissolving silica sand and bauxite in slag liquid, belonging to the technical field of mineral wool production from blast furnace slag.

Background

In the production of iron and steel enterprises, blast furnace slag is a derivative product of blast furnace ironmaking. In order to construct a resource-saving and environment-friendly society, the recycling economy needs to be developed vigorously, and the resource utilization efficiency is improved. The ultrafine powder produced by using blast furnace slag after flushing slag is used in the cement concrete industry, is one of the comprehensive utilization ways of blast furnace slag, and has been widely accepted by the industry in recent years. The production of the mineral wool by using the blast furnace hot slag is another way of blast furnace slag comprehensive utilization, and compared with the two ways, the production of the mineral wool utilizes the characteristic of sensible heat of the blast furnace hot slag, so that the energy is saved.

In the process of producing mineral wool by using blast furnace hot slag, a proper amount of auxiliary materials, such as silica sand or bauxite, are required to be added into liquid high-temperature slag to adjust the acidity coefficient of the slag, and the acidity coefficient range is controlled to be 1.2-1.3 so as to meet the production requirement of the mineral wool. The added silica sand or bauxite auxiliary material is concentrated and floats on the surface of the liquid slag, and the dissolution of the silica sand or bauxite is a slow process, so that the requirement of fast-paced mass production cannot be met. How to rapidly dissolve the added silica sand or bauxite and make the slag liquid components uniform becomes the problem to be solved in mineral wool production. Only by solving the problem, the uniform slag-liquid components and the stable quality of mineral wool products in the fast-paced mass production process can be ensured.

Disclosure of Invention

The invention aims to provide a process for quickly dissolving silica sand and bauxite in slag liquid, and the rapid dissolution of the silica sand or bauxite can be realized by stirring liquid high-temperature slag liquid with nitrogen.

The invention provides a process for quickly dissolving silica sand and bauxite in slag liquid, which comprises the following steps:

inserting a nitrogen pipeline into the hot slag through a furnace cover, inserting the nitrogen pipeline into the position 200-500cm below the surface of the high-temperature slag, and adjusting the flow corresponding to the nitrogen according to the difference of the liquid level of the slag in the furnace and the insertion depth to stir the slag liquid, the silica sand and the bauxite so as to realize the rapid dissolution of the silica sand and the bauxite in the slag liquid; the nitrogen pressure is kept between 0.5 and 0.6MPa, and the adopted nitrogen pipeline is made of hollow carbon rod materials.

In the scheme, the adding amount of the silica sand and the bauxite is more than 1200 kg/h, and strong stirring is used; the nitrogen pressure is kept between 0.5 and 0.6MPa, and strong stirring is performed when the nitrogen flow is controlled between 60 and 80L \ min;

the addition amount of the silica sand and the bauxite is 800-1200 kg/h, and weak stirring is used; the nitrogen pressure is kept between 0.5 and 0.6MP, and the nitrogen flow is weakly stirred when the nitrogen flow is controlled between 30 and 60L \ min.

The method utilizes the inertia of nitrogen, only plays a role of physical stirring, does not generate any chemical reaction with the slag, and does not change the slag components.

The nitrogen pipeline inserted into the liquid slag adopts a hollow carbon rod material in order to prevent high-temperature melting.

In order to prevent the outlet of the hollow carbon rod from being pasted by the molten slag, nitrogen is firstly introduced before the molten slag is inserted, the flow rate is kept to be not lower than 30L/min, and the nitrogen is also not closed before the hollow carbon rod is pulled out of the liquid molten slag.

The hollow carbon rods are connected in a threaded manner, the three sections form one carbon rod, the disassembly is convenient, the carbon rods can be lengthened according to the consumption degree of the carbon rods, the resources are saved, and each carbon rod is greatly utilized.

The principle of the invention is as follows: and inserting a nitrogen pipeline into the liquid high-temperature molten slag, and boiling the slag liquid when the pressure of nitrogen is adjusted to be 0.5-0.6 MPa to play a role in stirring so as to accelerate the dissolution speed of silica sand and bauxite in the slag liquid and produce mineral wool.

The invention has the beneficial effects that:

(1) in the process of producing mineral wool by using the blast furnace hot slag, the method realizes the rapid dissolution of the added auxiliary materials, ensures the uniform slag liquid components, meets the requirement of the mineral wool production process on rapid-rhythm continuous production, ensures the uniform hot slag components and realizes the purpose of stable quality of mineral wool products.

(2) The unit power consumption can be reduced by 233 kwh/t, and the unit power consumption cost can be reduced by 105 yuan/ton.

Detailed Description

The present invention is further illustrated by, but is not limited to, the following examples.

Example 1:

the method is used for trial production in the A furnace and the B furnace of the smelting operation area of the hot melting slag cotton manufacturing division of the Tai steel processing factory, one furnace is stirred by nitrogen gas, the other furnace is not stirred by nitrogen gas in the production process, and the contrast effect is obvious. The specific embodiment is as follows:

firstly, inserting a nitrogen pipeline into hot slag through a furnace cover, inserting the nitrogen pipeline into the position 200-500cm below the surface of the high-temperature slag, and adjusting the flow corresponding to nitrogen according to the difference of the liquid level of the slag in the furnace and the insertion depth to stir the slag liquid, the silica sand and the bauxite so as to realize the rapid dissolution of the silica sand and the bauxite in the slag liquid; the nitrogen pressure is kept between 0.5 and 0.6MPa, and the adopted nitrogen pipeline is made of hollow carbon rod materials.

In the embodiment, the adding amount of the silica sand and the bauxite is 1200 kg/h, the nitrogen pressure is kept between 0.5 and 0.6MPa, and the nitrogen flow is controlled at 60L/min;

After the implementation, the experimental data as given in table 1 below are obtained: comprises the dissolution speed of auxiliary materials, the hourly slag output and the composition data of hot melting slag.

TABLE 1

As can be seen from Table 1, when the nitrogen gas is used for stirring, the dissolving speed of the auxiliary materials can be increased by more than one time, the yield of the mineral wool is greatly improved, the components of the hot-melting slag are uniform, and the quality of the mineral wool is obviously improved.

TABLE 2

The dissolving speed of the auxiliary materials is increased to realize that the yield of the mineral wool is doubled, the unit power consumption can be greatly reduced, the unit power consumption can be reduced by 233 kwh/t and the unit power consumption cost can be reduced by 105 yuan/ton according to the calculation of the average electric quantity of the furnace A in single-line production of 2000kwh, the average electric quantity of the furnace B in B1600 kwh, the average electric quantity of the furnace A in double-line production of 2600kwh and the average electric quantity of the furnace B in 1800 kwh. The power consumption analysis is shown in Table 2.

Claims

1. A process for rapidly dissolving silica sand and bauxite in slag liquid is characterized by comprising the following steps:

inserting a nitrogen pipeline into the hot slag through a furnace cover, inserting the nitrogen pipeline into the position 200-500cm below the surface of the high-temperature slag, and adjusting the flow corresponding to the nitrogen according to the difference of the liquid level of the slag in the furnace and the insertion depth to stir the slag liquid, the silica sand and the bauxite so as to realize the rapid dissolution of the silica sand and the bauxite in the slag liquid; the nitrogen pressure is kept between 0.5 and 0.6MPa, and the adopted nitrogen pipeline is made of hollow carbon rod materials; before the nitrogen pipeline is inserted into the molten slag, nitrogen is introduced firstly, the flow rate is kept to be not lower than 30L/min, and the nitrogen is not closed before the nitrogen pipeline is pulled out of the liquid molten slag;

the adding amount of the silica sand and the bauxite is more than 1200 kg/h, and strong stirring is used; the nitrogen pressure is kept between 0.5 and 0.6MPa, and strong stirring is performed when the nitrogen flow is controlled between 60 and 80L/min;

the addition amount of the silica sand and the bauxite is 800-1200 kg/h, and weak stirring is used; the nitrogen pressure is kept between 0.5 and 0.6MP, and the nitrogen flow is weakly stirred when the nitrogen flow is controlled between 30 and 60L/min.

2. The process of claim 1 for rapidly dissolving silica sand and bauxite in a slag bath, wherein: the hollow carbon rod is in threaded connection, and three sections of the hollow carbon rod form a carbon rod.