阅读说明：本技术 一种微细粒铁矿物强磁选桥联团聚剂的使用方法 (Use method of micro-fine particle iron mineral strong magnetic separation bridging agglomerating agent ) 是由 马自飞 李文博 杨光 刘杰 李苑 袁立宾 于 2021-08-23 设计创作，主要内容包括：本发明涉及一种微细粒铁矿物强磁选桥联团聚剂的使用方法。具体步骤如下：首先在强磁选作业前的浓密机中添加微细粒铁矿物桥联团聚剂进行团聚预处理,然后将浓密机的沉砂给入高梯度强磁选机进行磁选。与现有技术相比,本发明的优点是：通过添加铁矿物桥联团聚剂进行预处理,从而增大目的矿物的表观尺寸,加快微细粒铁矿物的沉降,使得浓密机生产能力提高10%以上,同时减少浓密机溢流中微细粒铁矿物含量20%以上；通过团聚预处理可以显著提高磁介质对微细粒铁矿物的捕集能力,磁选作业回收率提高4%以上。(The invention relates to a use method of a micro-fine iron mineral strong magnetic separation bridging agglomerating agent. The method comprises the following specific steps: firstly, adding a micro-fine iron mineral bridging agglomerating agent into a thickener before strong magnetic separation operation for agglomeration pretreatment, and then feeding settled sand of the thickener into a high-gradient strong magnetic separator for magnetic separation. Compared with the prior art, the invention has the advantages that: the iron mineral bridging agglomerant is added for pretreatment, so that the apparent size of target minerals is increased, the sedimentation of micro-fine iron minerals is accelerated, the production capacity of the thickener is improved by more than 10%, and the content of the micro-fine iron minerals in overflow of the thickener is reduced by more than 20%; the trapping capacity of the magnetic medium to the micro-fine iron minerals can be obviously improved through agglomeration pretreatment, and the recovery rate of magnetic separation operation is improved by more than 4%.)

1. A use method of a micro-fine particle iron mineral strong magnetic separation bridging agglomerating agent is characterized by comprising the following steps:

step 1, firstly adding a dispersing agent into low-intensity magnetic separation tailing pulp with the concentration of 10-20%, adding a pH regulator to adjust the pH value of the low-intensity magnetic separation tailing pulp to 9.0-11.0, stirring by a stirrer for 3-10min at a stirring speed of 500-900r/min, and then adding an iron mineral bridging aggregating agent to enable micro-fine particle low-magnetic iron minerals in the low-intensity magnetic separation tailing pulp to form iron mineral aggregates under the action of the bridging aggregating agent to obtain blended pulp;

step 2, feeding the blended ore pulp obtained in the step 1 into a thickener for thickening to obtain underflow ore pulp of the thickener with the concentration of 30-50%, wherein the underflow ore pulp of the thickener is used as strong magnetic feeding ore pulp;

and 3, firstly adjusting the background magnetic field intensity, the pulse frequency and the pulse stroke of the strong magnetic separator, and then uniformly feeding the strong magnetic feeding ore pulp obtained in the step 2 into the strong magnetic separator for separation to obtain strong magnetic concentrate and strong magnetic tailing products.

2. The use method of the micro-fine iron ore strong magnetic separation bridging agglomerating agent according to claim 1, wherein in the step 1, the weak magnetic tailing pulp has an iron grade of 20% -35% and a particle size of-0.038 mm accounting for more than 85%.

3. The method for using the micro-fine iron mineral strong magnetic separation bridging agglomerating agent as claimed in claim 1, wherein in step 1, the dispersing agent is water glass, sodium hexametaphosphate or a mixture of the two, and the dosage is 1000g/t to 3000 g/t; the iron mineral bridging agglomerating agent is a mixture of cassava starch and polyacrylamide, and the using amount ratio of the cassava starch to the polyacrylamide is (10-20): 1.

4. The use method of the micro-fine iron mineral strong magnetic separation bridged agglomeration agent according to claim 1, wherein in the step 3, the type of the strong magnetic separator is a SLon-2000 vertical ring pulse strong magnetic separator.

5. The use method of the micro-fine iron mineral strong magnetic separation bridging agglomerating agent according to claim 1, wherein in the step 3, the background magnetic field intensity of the strong magnetic separator is 0.5-1.5T, the pulse stroke of the strong magnetic separator is 0-20 mm, and the pulse frequency of the strong magnetic separator is 0-300 times/min.

Technical Field

The invention belongs to the technical field of mineral processing, and particularly relates to a use method of a micro-fine iron mineral strong magnetic separation bridging agglomerating agent.

Background

The Anlung Steel group mining company is the unit for developing iron ore concentrate iron extraction and silicon reduction in domestic mine enterprises. The Anomasteel mining industry takes a Qida mountain concentrating mill as an implementation object, and after laboratory small-scale tests, stage industrial tests and semi-industrial tests, the technical improvement of a first-concentration workshop is completed in 6 months in 2000 according to stage ore grinding, coarse and fine separation, gravity separation, magnetic separation and anion reverse flotation. Hitherto, the industrial application of iron extraction and silicon reduction of refractory Anshan type iron ore is carried out in Anshan sintering plants, Qida mountain ore dressing branch plants, Bochanling mountain three-separation workshops and Anqian mining industry separation plants by adopting the principle of coarse and fine separation, gravity separation, magnetic separation and anion reverse flotation. The middle-sweeping magnetic operation and the fine-grain strong magnetic separation operation in the process play an important role in tailing discarding in the separation process, the total tailing discarding amount of the two-stage operation accounts for more than 70% of the total tailing discharge in each separation plant, and good conditions are created for obtaining high concentrate grade and reducing the use amount of flotation reagents in the flotation operation. With the change of ore properties and the increase of the operation life of equipment, the strong magnetic tailing discarding operation also becomes a key link of iron loss, the recovery effect of strong magnetic separation still needs to be improved for fine-grained strong magnetic feeding with the content of-0.074 exceeding 90 percent, especially for iron minerals with the granularity smaller than 20 mu m, and the failure of effective recovery of the part of micro-grained iron minerals is also the root cause of higher strong magnetic tailings. Therefore, the development of key technical research for strengthening the strong magnetic separation recovery of the fine-grained iron minerals has great significance for improving the utilization rate of iron ore resources, deeply improving quality, reducing impurities, strengthening emission reduction and improving efficiency. In addition, since a thickening process is required before the high-gradient magnetic separation operation, a large amount of fine iron minerals are lost to the overflow.

The result of dynamics research on the sorting process of the micro-fine mineral shows that the main reason for difficulty in sorting the micro-fine mineral is that the mineral particle size is small, and on the one hand, the collecting capacity of a magnetic medium for weakly magnetic minerals is insufficient in the conventional magnetic separation operation due to the fact that the mineral particles are fine; on the other hand, in the conventional flotation operation, the collision and attachment probability of air bubbles and particles is reduced, and the agent selectivity is reduced due to the increase of the surface energy and the specific surface area of the particles, so that the beneficiation scholars propose an agglomeration separation process for enhancing the separation of fine-grained minerals by increasing the apparent size of the mineral particles. According to different agglomeration mechanisms of fine ore particles, the agglomeration sorting process is mainly divided into a polymer flocculation sorting process, a magnetic agglomeration and magnetic seed agglomeration sorting process, a hydrophobic flocculation sorting process and a composite agglomeration sorting process. However, in practical application, the magnetic seeds added in the magnetic seed agglomeration separation process are usually strong magnetic particles, and the strong magnetic particles can seriously block a magnetic medium in a high-gradient strong magnetic separation process, so that a high-gradient strong magnetic separator cannot normally operate; in the hydrophobic flocculation separation process, a surfactant is usually required to be added into ore pulp, the surfactant can seriously influence the reverse flotation operation of the iron ore, and the process usually needs stronger mechanical stirring strength, so that the application of the process in the existing iron ore dressing flow is limited.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a using method of a micro-fine iron mineral strong magnetic separation bridging agglomerating agent, aiming at changing the operational parameters of bridging agglomeration operation to optimize the structural characteristics of the iron mineral bridging agglomerating agent, reducing the loss of overflow extra-fine iron mineral of a thickener, reducing the tailing grade of a strong magnetic separator and improving the iron recovery rate of the strong magnetic separation operation by adjusting the adding amount of the bridging agglomerating agent.

The invention is realized by the following technical scheme:

the invention discloses a using method of a micro-fine iron mineral strong magnetic separation bridging agglomerating agent, which is characterized by comprising the following steps:

step 1, firstly adding a dispersing agent into weak magnetic tailing pulp with the concentration of 10-20%, then adding a pH regulator to adjust the pH value of the weak magnetic tailing pulp to 9.0-11.0, stirring by adopting a stirrer, then adding an iron mineral bridging aggregating agent, controlling the stirring time to be 3-10min, and stirring the mixture at the rotating speed of 500-;

step 2, feeding the blended ore pulp obtained in the step 1 into a thickener for thickening to obtain underflow ore pulp of the thickener with the concentration of 30-50%, wherein the underflow ore pulp of the thickener is used as strong magnetic feeding ore pulp;

and 3, firstly adjusting the background magnetic field intensity, the pulse frequency and the pulse stroke of the wet type vertical ring high-gradient strong magnetic separator, and then uniformly feeding the strong magnetic feeding ore pulp obtained in the step 2 into the strong magnetic separator for separation to obtain strong magnetic concentrate and a strong magnetic tailing product.

Further, in the step 1, the iron grade of the weak magnetic tailing pulp is 20% -35%, and the granularity of-0.038 mm accounts for more than 85%.

Further, in the step 1, the dispersant is water glass, sodium hexametaphosphate or a mixture of the water glass and the sodium hexametaphosphate, and the dosage is 1000g/t-3000 g/t; the iron mineral bridging agglomerating agent is a mixture of cassava starch and polyacrylamide, and the using amount ratio of the cassava starch to the polyacrylamide is (10-20): 1.

Further, in step 3, the model of the strong magnetic separator is a SLon-2000 vertical ring pulsating strong magnetic separator.

Further, in the step 3, the background magnetic field intensity of the strong magnetic separator is 0.5-1.5T, the pulse stroke of the strong magnetic separator is 0-20 mm, and the pulse frequency of the strong magnetic separator is 0-300 times/min.

Working mechanism of bridged agglomerated fine iron ore

Before the strong magnetic separation operation, the micro-fine iron mineral bridging agglomeration agent is added into the low magnetic separation tailing pulp containing the micro-fine iron mineral for pretreatment, so that the apparent size of the target mineral is increased, on one hand, the sedimentation of the micro-fine iron mineral can be accelerated in the thickening process of a thickener before the strong magnetic separation, the production capacity of the thickener is improved, the loss of the micro-fine iron mineral in the overflow of the thickener is reduced, on the other hand, the particle size requirement of the subsequent strong magnetic separation operation can be met, the trapping capacity of a magnetic medium on the micro-fine iron mineral is improved, and meanwhile, the influence of adverse factors such as mechanical entrainment, a slime cover and the like can be reduced. In order to improve the structural strength of the floc, cassava starch containing a branched chain structure and polyacrylamide with a long chain structure are mixed according to a certain proportion to be used as a bridging agglomerating agent of micro-fine iron minerals, and the structural characteristics of the bridging agglomerating agent of the iron minerals are optimized by changing the operational parameters of bridging agglomerating operation by adjusting the addition amount of the bridging agglomerating agent, so that the bridging agglomerating agent is suitable for strong magnetic separation operation, and the recovery rate of the strong magnetic separation operation is improved.

Compared with the prior art, the invention has the advantages that:

compared with the existing recovery process of the strengthened micro-fine particle weak magnetic iron minerals, the method has the advantages of high iron recovery rate, low comprehensive cost, simple process structure and the like:

(1) according to the invention, the iron mineral bridging agglomerating agent is added for pretreatment, so that the apparent size of the target mineral is increased, the sedimentation of the micro-fine iron mineral is accelerated, the production capacity of the thickener is improved by more than 10%, and the content of the micro-fine iron mineral in the overflow of the thickener is reduced by more than 20%;

(2) the trapping capacity of the magnetic medium to the micro-fine iron minerals can be obviously improved through agglomeration pretreatment, and the recovery rate of magnetic separation operation is improved by more than 4%.

Drawings

FIG. 1 is a block diagram of the steps performed by the present invention.

Detailed Description

The invention is further illustrated by the following figures and examples.

The following non-limiting examples are presented to enable those of ordinary skill in the art to more fully understand the present invention and are not intended to limit the invention in any way.

The reagents and materials described in the following examples are commercially available, unless otherwise specified.

The stirrer used in the embodiment of the invention is XJT-II type. The specification of the vertical ring pulsating strong magnetic separator adopted in the embodiment of the invention is Slon-2000 type,

in the embodiment of the invention, a NaOH solution with the mass concentration of 5% is used as a pH regulator.

The mineral powder containing the micro-fine particle weak magnetic iron mineral adopted in the embodiment of the invention contains TFe = 25-30 wt%, FeO = 5-10 wt%, SiO2= 40-60 wt%, Al2O3= 0.1-5 wt%, MgO = 0.1-5 wt%, CaO = 0.1-5 wt%, S = 0.1-0.5 wt%, and P = 0.01-0.5 wt%.

Example 1

(1) Taking two parts of weakly magnetic separation tailing ore pulp with TFe grades of 26.65 percent and 26.61 percent respectively, the concentration of 10 percent and the granularity of-0.038 mm accounting for more than 95 percent and containing weakly magnetic iron minerals, adding dispersant water glass, the using amount of 1500g/t, adding NaOH with the mass concentration of 5 percent, stirring for 5min at a constant speed by a stirrer under the condition that the stirring speed is 900r/min, and adjusting the pH value of the ore pulp to 10.0; adding a cassava starch-polyacrylamide mixture solution with selective bridging and agglomerating functions on iron minerals into one part of ore pulp, wherein the using amount ratio of the cassava starch to the polyacrylamide is 15:1, the using amount of a medicament is 100g/t, stirring at a constant speed for 5min to enable the iron minerals in the ore pulp to form weak magnetic iron mineral floccules with certain strength and moderate size through the bridging action of the cassava starch, and adding no cassava starch-polyacrylamide mixture solution into the other part of the ore pulp;

(2) feeding the two portions of pulp after size mixing into a thickener for thickening until the concentration is 30 percent;

(3) and uniformly feeding the ore pulp concentrated by the thickener into a vertical ring pulse strong magnetic separator for separation under the conditions that the background magnetic induction intensity is 1.0 Tesla, the pulse stroke of the magnetic separator is 20mm and the pulse frequency is 200 times/min, so as to obtain magnetic concentrate and magnetic tailing products. Through comparison of separation indexes of the two processes, the strong magnetic roughing magnetic product with the iron grade of 48.92% and the iron recovery rate of 80.36% can be obtained by adding the bridging agglomeration agent for size mixing and then performing strong magnetic separation, compared with the product without the bridging agglomeration agent, the iron grade change is not large, the iron recovery rate is improved by 5.20%, and meanwhile, the iron grade in the overflow product of the thickener is reduced by 1.20%.

Example 2

(1) Taking two parts of weakly magnetic separation tailing ore pulp with TFe grade of 27.55 percent and 27.61 percent respectively, concentration of 15 percent and granularity of-0.038 mm accounting for more than 98 percent and containing weakly magnetic iron minerals, adding dispersant water glass with the dosage of 1500g/t, adding NaOH with the mass concentration of 5 percent, stirring for 5min at a constant speed by adopting a stirrer under the condition that the stirring speed is 800r/min, and adjusting the pH value of the ore pulp to be 9.0; adding a cassava starch-polyacrylamide mixture solution with selective bridging and agglomerating effects on iron minerals into one part of ore pulp, wherein the using amount ratio of the cassava starch to the polyacrylamide is 15:1, the using amount of a medicament is 150g/t, stirring at a constant speed for 5min to enable the iron minerals in the ore pulp to form weak magnetic iron mineral floccules with certain strength and moderate size through the bridging effect of the cassava starch, and adding no cassava starch-polyacrylamide mixture solution into the other part of the ore pulp;

(2) feeding the two portions of pulp after size mixing into a thickener for thickening until the concentration is 35 percent;

(3) and uniformly feeding the ore pulp concentrated by the thickener into a vertical ring pulse strong magnetic separator for separation under the conditions that the background magnetic induction intensity is 1.3 Tesla, the pulse stroke of the magnetic separator is 20mm and the pulse frequency is 250 times/min, so as to obtain magnetic concentrate and magnetic tailing products. Through comparison of separation indexes of the two processes, the strong magnetic roughing magnetic product with the iron grade of 50.92% and the iron recovery rate of 83.36% can be obtained by adding the bridging agglomerating agent for size mixing and then performing strong magnetic separation, compared with the product without the bridging agglomerating agent, the iron grade change is not large, the iron recovery rate is improved by 4.5%, and the iron grade in the overflow product of the thickener is reduced by 1.5%.

Example 3

(1) Taking two parts of weakly magnetic separation tailing ore pulp with TFe grades of 28.65 percent and 29.01 percent respectively, the concentration of 20 percent and the granularity of-0.038 mm accounting for more than 95 percent and containing weakly magnetic iron minerals, adding dispersant water glass, adding NaOH with the mass concentration of 5 percent, stirring for 5 minutes by adopting a stirrer at a constant speed under the condition that the stirring speed is 950r/min, and adjusting the pH value of the ore pulp to be 10.0; adding a cassava starch-polyacrylamide mixture solution with selective bridging and agglomerating functions on iron minerals into one part of ore pulp, wherein the using amount ratio of the cassava starch to the polyacrylamide is 15:1, the using amount of a medicament is 200g/t, stirring at a constant speed for 5min to enable the iron minerals in the ore pulp to form weak magnetic iron mineral floccules with certain strength and moderate size through the bridging action of the cassava starch, and adding no cassava starch-polyacrylamide mixture solution into the other part of the ore pulp;

(2) feeding the two portions of pulp after size mixing into a thickener for thickening until the concentration is 33%;

(3) and uniformly feeding the ore pulp concentrated by the thickener into a vertical ring pulse strong magnetic separator for separation under the conditions that the background magnetic induction intensity is 1.0 Tesla, the pulse stroke of the magnetic separator is 20mm and the pulse frequency is 200 times/min, so as to obtain magnetic concentrate and magnetic tailing products. Through comparison of separation indexes of the two processes, the strong magnetic roughing magnetic product with the iron grade of 50.02% and the iron recovery rate of 79.36% can be obtained by adding the bridging agglomeration agent for size mixing and then performing strong magnetic separation, compared with the product without the bridging agglomeration agent, the iron grade change is not large, the iron recovery rate is improved by 4.80%, and meanwhile, the iron grade in the overflow product of the thickener is reduced by 0.90%.

Example 4

(1) Taking two parts of weakly magnetic separation tailing pulp with TFe grades of 25.65 percent and 25.61 percent respectively, the concentration of 15 percent and the granularity of-0.038 mm accounting for more than 95 percent and containing weakly magnetic iron minerals, adding dispersant water glass with the dosage of 1500g/t, adding NaOH with the mass concentration of 5 percent, stirring for 5min at a constant speed by adopting a stirrer under the condition that the stirring speed is 800r/min, and adjusting the pH value of the pulp to be 9.0; adding a cassava starch-polyacrylamide mixture solution with selective bridging and agglomerating functions on iron minerals into one part of ore pulp, wherein the using amount ratio of the cassava starch to the polyacrylamide is 15:1, the using amount of a medicament is 200g/t, stirring at a constant speed for 5min to enable the iron minerals in the ore pulp to form weak magnetic iron mineral floccules with certain strength and moderate size through the bridging action of the cassava starch, and adding no cassava starch-polyacrylamide mixture solution into the other part of the ore pulp;

(2) feeding the two portions of pulp after size mixing into a thickener for thickening until the concentration is 30 percent;

(3) and uniformly feeding the ore pulp concentrated by the thickener into a vertical ring pulse strong magnetic separator for separation under the conditions that the background magnetic induction intensity is 1.3 Tesla, the pulse stroke of the magnetic separator is 20mm and the pulse frequency is 200 times/min, so as to obtain magnetic concentrate and magnetic tailing products. Through comparison of separation indexes of the two processes, a strong magnetic roughing magnetic product with the iron grade of 48.63% and the iron recovery rate of 85.36% can be obtained by adding a bridging agglomerating agent for size mixing and then performing strong magnetic separation, compared with the product without the bridging agglomerating agent, the iron grade change is small, the iron recovery rate is improved by 4.70%, and the iron grade in an overflow product of a thickener is reduced by 1.10%.

The dispersant can be water glass, sodium hexametaphosphate or a mixture of the water glass and the sodium hexametaphosphate.

Compared with the existing recovery process of the strengthened micro-fine particle weak magnetic iron minerals, the method has the advantages of high iron recovery rate, low comprehensive cost, simple process structure and the like.