阅读说明：本技术 一种利用矿山尾矿细泥制备碱性球团矿的方法 (Method for preparing alkaline pellet ore by using mine tailing fine mud ) 是由 高恩 余东晓 杨大兵 刘和平 罗之礼 毛少波 张�浩 谭铭 谢百勤 黄金涛 于 2020-04-13 设计创作，主要内容包括：本发明涉及球团矿制备工艺领域,尤其涉及一种利用矿山尾矿细泥制备碱性球团矿的方法。本发明所设计的利用矿山尾矿细泥制备碱性球团矿的方法,包括步骤：1)矿山尾矿细泥的预处理：首先对矿山尾矿细泥进行分别进行搅拌、分选工序得到分选后的矿山尾矿细泥；然后对分选后的矿山尾矿细泥进行浓缩、过滤烘干、高压辊磨得到矿山尾矿粉；2)配料：按照质量份数,矿山尾矿粉3.3～4.5份,铁精矿粉100份,粘结剂1.5～1.8份,进行混合得到混合料；3)造球：将混合料经过圆盘造球机进行造球得到生球；4)焙烧：将生球输送到链篦机上依次进行干燥、预热、焙烧和冷却工序得到成品球团矿。本发明资源化利用矿山尾矿细泥制备得到碱度为1.0～1.3的碱性球团矿。(The invention relates to the field of pellet preparation processes, in particular to a method for preparing alkaline pellets by using mine tailing fine mud. The invention discloses a method for preparing alkaline pellets by using mine tailing fine mud, which comprises the following steps: 1) pretreatment of mine tailing fine mud: firstly, respectively stirring and sorting mine tailing fine mud to obtain sorted mine tailing fine mud; then concentrating, filtering, drying and high-pressure roller milling the separated fine mud of the mine tailings to obtain mine tailing powder; 2) preparing materials: mixing 3.3-4.5 parts of mine tailing powder, 100 parts of iron concentrate powder and 1.5-1.8 parts of binder according to parts by weight to obtain a mixture; 3) pelletizing: pelletizing the mixture by a disc pelletizer to obtain green pellets; 4) roasting: and conveying the green pellets to a chain grate machine for drying, preheating, roasting and cooling in sequence to obtain finished pellet ore. The alkaline pellet ore with alkalinity of 1.0-1.3 is prepared by recycling mine tailing fine mud.)

1. A method for preparing alkaline pellets by using fine mud of mine tailings comprises the following steps:

1) pretreatment of mine tailing fine mud: firstly, respectively stirring and sorting mine tailing fine mud raw materials to obtain sorted mine tailing fine mud; then concentrating, filtering, drying and high-pressure roller milling the separated fine mud of the mine tailings to obtain mine tailing powder;

2) preparing materials: mixing 3.3-4.5 parts of mine tailing powder, 100 parts of iron concentrate powder and 1.5-1.8 parts of binder according to parts by weight to obtain a mixture;

3) pelletizing: pelletizing the mixture by a disc pelletizer to obtain green pellets;

4) roasting: and conveying the green pellets to a chain grate machine for drying, preheating, roasting and cooling in sequence to obtain finished pellet ore.

2. The method for preparing alkaline pellets from mine tailing fine mud according to claim 1, wherein the mine tailing fine mud in the step 1) is prepared from tailing fine mud accumulated in a tailing pond, and comprises the following components in percentage by mass: CaO is more than or equal to 42 percent, MgO is more than or equal to 9 percent, and SiO₂≥5.65％。

3. The method for preparing alkalinity by using mine tailing fine mud according to claim 1The method for the pellets is characterized in that a chute sorting process is adopted in the sorting procedure in the step 1), a high-frequency vibration spiral chute is adopted as the chute, the pitch h/D of the spiral chute is 0.32-0.6, and the mineral components of the mine tailing fine mud after sorting meet the conditions that CaO is more than or equal to 56 percent, MgO is more than or equal to 14.6 percent, and SiO is more than or equal to 14.6 percent₂≤3.8％。

4. The method for preparing alkaline pellets from mine tailing fine mud according to claim 1, wherein the high-pressure roller milling in the step 1) enables the grain size of the mine tailing powder to reach 200 meshes to be more than 98%, and 325 meshes to be more than 90-92%.

5. The method for preparing alkaline pellets from the mine tailing fine mud as claimed in claim 1, wherein the binder in the step 2) is bentonite or an organic binder.

6. The method for preparing alkaline pellets from the mine tailing fine mud according to claim 1, wherein the particle size of the green pellets in the step 3) is 8-16 mm.

7. The method for preparing alkaline pellets by using the mine tailing fine mud as claimed in claim 1, wherein the drying in the step 4): the temperature is 250-350 ℃, and the time is 3-5 minutes; preheating: the temperature is 850-1050 ℃, and the time is 20-25 minutes; and (3) roasting: the temperature is 1200-1300 ℃, and the time is 12-18 minutes; and (3) cooling: the temperature is less than or equal to 150 ℃, and the time is 2-5 minutes.

Technical Field

The invention relates to the field of pellet preparation processes, in particular to a method for preparing alkaline pellets by using mine tailing fine mud.

Background

Pellet ore is one of main raw materials for blast furnace ironmaking, and currently, common acidic pellet ore is mainly produced from pellet ore in China. The acid pellets are naturally alkaline pellets, SiO₂And Al₂0₃The content of such elements is relatively high, and the content of alkaline substances such as calcium and magnesium is small, so that alkaline pellets are usually used in combination in order to balance the basicity of the slag in the blast furnace. The alkaline pellet ore is a ball-type iron-containing material which can meet the requirements of iron and steel smelting at present, and is obtained by mixing finely ground iron ore concentrate or other iron-containing powder with an additive or a binder according to a certain proportion, pelletizing, and then hardening and consolidating the mixture by adopting methods such as drying, roasting and the like, and related reports exist in the prior art for producing the pellet ore by utilizing mine tailing fine mud, for example, the invention patent application document with the application number of 201510508537.3 records '1', and the tailing powder with high CaO and MgO contents is obtained by treating the tailing mud through an ore dressing process; 2, pre-roasting the tailing powder; 3, preparing materials; 4, mixing and pelletizing; 5, roasting; however, the flux-type MgO pellet produced by the patent application has the binary alkalinity of below 0.7 and smaller alkalinity, and still cannot meet the requirements of alkaline pellets used for blast furnace iron making.

Disclosure of Invention

In order to solve the problems, the invention aims to provide a method for preparing alkaline pellets by using mine tailing fine mud, which can be used for preparing alkaline pellets with alkalinity of 1.0-1.3 by recycling the mine tailing fine mud.

In order to achieve the purpose, the method for preparing the alkaline pellet ore by using the fine mud of the mine tailings comprises the following steps:

1) pretreatment of mine tailing fine mud: firstly, respectively stirring and sorting mine tailing fine mud raw materials to obtain sorted mine tailing fine mud; then concentrating, filtering, drying and high-pressure roller milling the separated fine mud of the mine tailings to obtain mine tailing powder;

2) preparing materials: mixing 3.3-4.5 parts of mine tailing powder, 100 parts of iron concentrate powder and 1.5-1.8 parts of binder according to parts by weight to obtain a mixture;

3) pelletizing: pelletizing the mixture by a disc pelletizer to obtain green pellets;

4) roasting: and conveying the green pellets to a chain grate machine for drying, preheating, roasting and cooling in sequence to obtain finished pellet ore.

As a preferred scheme, the raw material of the fine mud of the mine tailings in the step 1) is the fine mud of the tailings stacked in a tailings pond, and the raw material comprises the following components in percentage by mass: CaO is more than or equal to 42 percent, MgO is more than or equal to 9 percent, and SiO₂≥5.65％。

As a preferable scheme, a chute sorting process is adopted in the sorting procedure in the step 1), the chute adopts a high-frequency vibration spiral chute, and the pitch h/D of the spiral chute is 0.32-0.6; the specific sorting process is as follows: the spiral chute is connected with the vibrator, the vibrator is started, the ore pulp is fed from the ore feeding hopper, the water is fed to the ore feeding hopper, the fed ore pulp is in centrifugal rotary motion downwards along a spiral line under the action of gravity, mineral particles vibrate in a reciprocating mode to increase the kinetic energy of the mineral particles, meanwhile, the mineral particles interact with each other, the coarse particle density and the fine particle density move inwards of the spiral chute, the fine particle density and the fine particle density move outwards of the spiral, the solid particles are loose under the action of weak turbulence, the separation principle of a flowing film is adopted for layering, and the heavy minerals entering the bottom layer are subjected to tank bottomThe influence of friction force, low movement speed and small centrifugal force inertia tend to move in the groove along the maximum inclined direction of the groove surface; the doped micro-particles are impacted to the upper layer by vibration, are accelerated by the action of water flow and are thrown to the outer side of the groove surface; heavy minerals and micro minerals gradually form a belt layer under the action of continuous vibration, the belt layer is flatly paved on the surface of the groove, the movement of mineral particles tends to be stable, and the belt layer separation is finished, so that the final separation is realized, and the mineral components of the fine mud of the mine tailings after the separation meet the conditions that CaO is more than or equal to 56 percent, MgO is more than or equal to 14.6 percent, and SiO₂Less than or equal to 3.8 percent. The high-frequency vibration spiral chute separation process is adopted, and the mineral separation precision is high.

Preferably, the high-pressure roller milling in the step 1) enables the particle size of the mine tailing powder to reach 200 meshes to be more than 98%, and the 325 meshes to be more than 90-92%.

Preferably, the binder in the step 2) is bentonite or an organic binder.

Preferably, the particle size of the green pellets in the step 3) is 8-16 mm.

Preferably, the drying in step 4): the temperature is 250-350 ℃, and the time is 3-5 minutes; preheating: the temperature is 850-1050 ℃, and the time is 20-25 minutes; and (3) roasting: the temperature is 1200-1300 ℃, and the time is 12-18 minutes; and (3) cooling: the temperature is less than or equal to 150 ℃, and the time is 2-5 minutes. The preheating temperature is 850-1050 ℃, so that the carbonate is fully decomposed.

The invention has the advantages that: compared with the traditional process for producing the pellet by using the mine tailing fine mud, the invention comprehensively considers the alkalinity, the strength and the cost of the pellet, and adjusts the component proportion of the ingredients to obtain the pellet with the alkalinity of 1.0-1.3 and the compressive strength of more than 2548N/pellet; on one hand, the invention utilizes the high content of calcium and magnesium in the mine tailing fine mud to meet the alkalinity requirement, and uses a large amount of accumulated mine tailing fine mud to save the raw material cost for preparing the pellet; on the other hand, the characteristic of fine granularity of mine tailing fine mud is utilized, so that pelletizing of the pellets is facilitated, a binder can be partially replaced, and meanwhile, the addition of the binder is reduced, and the pellets can be reducedSiO in mine₂、Al₂O₃The content of the components in the pellet further improves the compression strength of the pellet.

Drawings

FIG. 1 is a process flow chart of the invention for preparing alkaline pellets by using mine tailing fine mud.

Detailed Description

For a better understanding of the present invention, reference will now be made in detail to the present invention, examples of which are illustrated in the accompanying drawings.