Process for thickening and filtering non-metallic ore

Abstract

The invention belongs to the technical field of ore grading and processing, and particularly provides a non-metallic ore thickening and filtering process which specifically comprises the following steps: step 1, ore pulp premixing; carrying out size mixing treatment on the magnetite concentrate to form magnetite concentrate pulp; step 2, mixing and feeding; the magnetite concentrate pulp is pumped into a thickener feeding mine, the magnetite concentrate pulp and the non-metal ore concentrate pulp are fully mixed in the feeding mine, and mixed ore pulp is formed; step 3, thickening; step 4, wet magnetic separation; and step 5, filtering. According to the process, on the premise that the equipment scale is not changed, the production efficiency of the thickener is improved by 15%-20%, the underflow concentration of the thickener is improved by 5%-10%, the dosage of a flocculating agent is reduced by 5%, the phosphorus concentrate moisture is reduced by 5%-8%, the difference between the equipment structure and an old production line is small, the refitting cost of refitting the old production line into the process production line is low, the refitting difficulty is small, and the cost is low. Therefore, the process has a good popularization prospect.

Description

Technical Field

[0001] This invention belongs to the field of ore beneficiation and processing technology, and specifically provides a thickening and filtration process for non-metallic minerals. Background Technology

[0002] Iron is often found as an associated component in non-metallic minerals. In the processing of non-metallic minerals, thickeners, as a key solid-liquid separation device, are widely used in the concentration and dewatering of slurry. Through gravity settling, solid particles in the slurry gradually sink to form a thick underflow, while clearer water precipitates out from the top, thus achieving effective solid-liquid separation.

[0003] Based on feedback from frontline factories, it has been found that when processing non-metallic mineral slurries, if the particle size is very fine, a mixing phenomenon may occur during the thickening process. This phenomenon will have the following effects: 1. Fine-grained concentrate overflows from the overflow, reducing the concentrate recovery rate; Second, the entry of fine-grained concentrate into the circulating water system has a negative impact on the subsequent reuse of circulating water; Third, during the thickening process, the sedimentation rate of finer slurry is slower, which leads to an increase in the underflow concentration of the thickener, affecting the processing capacity of subsequent filtration operations. Moreover, the processing capacity of the thickener is far below the rated value. This results in thickeners generally having a lower processing capacity than their rated capacity. To meet processing needs, thickeners that are far larger than the actual requirements must be selected. Summary of the Invention

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a thickening and filtration process for non-metallic minerals, the specific steps of which include: Step 1: Premixing the slurry; Magnetite concentrate is slurry-processed to form magnetite concentrate slurry; Step 2, mixing and feeding; The magnetite concentrate slurry is pumped into the thickener feed shaft, where it is fully mixed with the non-metallic mineral concentrate slurry to form a mixed slurry. Step 3, Thickening; The mixed slurry is fed into a thickener for thickening. Step 4: Wet magnetic separation; Wet magnetic separation is performed using a magnetic separator to recover magnetite from the mixed slurry; The recovered magnetite concentrate is then fed back into the next work cycle. The slurry from the magnetite concentrate is then used for subsequent filtration. Step 5, Filtering; The phosphate concentrate is filtered using a filter press to obtain the final phosphate concentrate filter cake, and the filtrate is returned to the circulating water system.

[0005] Furthermore, the magnetite concentrate used in step one has a grade of over 66% and a particle size of -200 mesh to +325 mesh.

[0006] Furthermore, in step one, the weight ratio of non-metallic minerals to magnetite concentrate is 20:1.

[0007] Furthermore, in step three, a high-efficiency thickener is used to carry out the thickening process.

[0008] Furthermore, in step four, a drum magnetic separator is used to carry out the magnetite concentrate recovery process.

[0009] Furthermore, step five involves a disc vacuum filter process.

[0010] Furthermore, the drum magnetic separator is a semi-countercurrent type drum magnetic separator, with the magnetic field strength set at 1500GS.

[0011] The beneficial effects of using this invention are: This process uses magnetite concentrate as a settling accelerator in the thickener, which can increase the thickener's production efficiency by 15%-20%, increase the thickener's underflow concentration by 5%-10%, reduce flocculant usage by 5%, and reduce the moisture content of phosphate concentrate by 5%-8% without changing the equipment scale. The equipment structure is not significantly different from the old production line, and the conversion cost and difficulty of converting the old production line to this process are low. Therefore, this process has good prospects for promotion. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the thickening and filtration process of the present invention; Figure 2 This is a schematic diagram of a conventional thickening and filtration process; Detailed Implementation

[0013] The present invention will now be described in detail with reference to the accompanying drawings.

[0014] Reference Figure 1 A thickening and filtration process for non-metallic minerals, the specific steps of which include: Step 1: Premixing the slurry; Magnetite concentrate is slurry-processed to form magnetite concentrate slurry; Step 2, mixing and feeding; The magnetite concentrate slurry is pumped into the thickener feed shaft, where it is fully mixed with the non-metallic mineral concentrate slurry to form a mixed slurry. Step 3, Thickening; The mixed slurry is fed into a thickener for thickening. When flocculant is added to the thickener, mineral particles will form flocs. After adding magnetite concentrate, the flocs will be heavier, the settling speed will be faster, and flocs that could not settle before will also settle, thus achieving the purpose of accelerating the settling speed and enhancing the settling effect. This will improve the equipment's processing capacity, increase the underflow concentration, reduce the amount of mineral particles carried, and improve the overflow quality. Under the premise of ensuring stable settling effect, the amount of flocculant used can also be reduced. Overflow water is recycled as circulating water and reused in other processes; The underflow then proceeds to the subsequent filtration process; Step 4: Wet magnetic separation; Wet magnetic separation is performed using a magnetic separator to recover magnetite from the mixed slurry; The recovered magnetite concentrate is then fed back into the next work cycle. The slurry from the magnetite concentrate is then used for subsequent filtration. Step 5, Filtering; The phosphate concentrate is filtered using a filter press to obtain the final phosphate concentrate filter cake, and the filtrate is returned to the circulating water system.

[0015] Preferably, the magnetite concentrate used in step one has a grade of 66% or higher and a particle size of -200 mesh to +325 mesh.

[0016] Preferably, the weight ratio of non-metallic minerals to magnetite concentrate is 20:1.

[0017] Preferably, a high-efficiency thickener is used to perform the thickening process in step three.

[0018] Preferably, in step four, a drum magnetic separator is used to carry out the magnetite concentrate recovery process.

[0019] Preferably, step five involves a disc vacuum filter process.

[0020] Example 1

[0021] Reference Figure 1 It adopts a thickener with a diameter of 50m for mine use, a two-stage semi-countercurrent drum magnetic separator and a 72㎡ disc vacuum filter; The magnetic field strength of the drum magnetic separator is set to 1500GS. The specific process for processing phosphate concentrate using this technology is as follows: The magnetite concentrate slurry and phosphate concentrate slurry after slurry preparation are pumped into the feed well at a weight ratio of 20:1. The two are mixed with flocculant in the feed well and then thickened by a thickener to produce a mixed slurry with an underflow concentration of 50%. The mixed slurry is fed into a drum magnetic separator for wet magnetic separation to separate and recover magnetite from the mixed slurry. The magnetite is then transported to a slurry conditioning tank, where it is re-conditioned and recycled. The tailings slurry is fed into a disc vacuum filter. The disc vacuum filter produces phosphate powder with a moisture content of less than 10%, with a production efficiency of 90 tons per hour.

[0022] Reference Figure 2 The conventional process involves a thickener directly connected to a filter. Phosphate concentrate slurry is pumped through a pipeline to the thickener feed shaft, where it is mixed with flocculant and thickened to produce a slurry with an underflow concentration of 50%. This slurry is then fed into a vacuum filter to produce phosphate concentrate powder with a moisture content of less than 10%. The production efficiency is 60 tons of phosphate concentrate per hour.

[0023] This process can increase the thickener's production efficiency by 15%-20%, increase the thickener's underflow concentration by 5%-10%, reduce flocculant usage by 5%, and reduce phosphate concentrate moisture content by 5%-8% without changing the equipment scale.

[0024] The equipment cost of the drum magnetic separator is controllable, and the magnetic separation loss of magnetite concentrate is minimal; This shows that the cost and difficulty of retrofitting old production lines are not high, and they have good prospects for promotion.

[0025] The above content is only a preferred embodiment of the present invention. For those skilled in the art, many changes can be made in the specific implementation and application scope based on the concept of the present invention. As long as these changes do not depart from the concept of the present invention, they all fall within the protection scope of the present invention.

Claims

1. A thickening and filtration process for non-metallic minerals, characterized in that: The specific steps include: Step 1: Premixing the slurry; Magnetite concentrate is slurry-processed to form magnetite concentrate slurry; Step 2, mixing and feeding; The magnetite concentrate slurry is pumped into the thickener feed shaft, where it is fully mixed with the non-metallic mineral concentrate slurry to form a mixed slurry. Step 3, Thickening; The mixed slurry is fed into a thickener for thickening. Step 4: Wet magnetic separation; Wet magnetic separation is performed using a magnetic separator to recover magnetite from the mixed slurry; The recovered magnetite concentrate is then fed back into the next work cycle. The slurry from the magnetite concentrate is then used for subsequent filtration. Step 5, Filtering; The phosphate concentrate is filtered using a filter press to obtain the final phosphate concentrate filter cake, and the filtrate is returned to the circulating water system.

2. The thickening and filtration process for non-metallic minerals according to claim 1, characterized in that: The magnetite concentrate used in step one has a grade of over 66% and a particle size of -200 mesh to +325 mesh.

3. The thickening and filtration process for non-metallic minerals according to claim 1, characterized in that: In step one, the weight ratio of non-metallic minerals to magnetite concentrate is 20:

1.

4. The thickening and filtration process for non-metallic minerals according to claim 1, characterized in that: In step three, a high-efficiency thickener is used to carry out the thickening process.

5. The thickening and filtration process for non-metallic minerals according to claim 1, characterized in that: Step four involves using a drum magnetic separator to recover magnetite concentrate.

6. The thickening and filtration process for non-metallic minerals according to claim 1, characterized in that: Step five involves a disc vacuum filter process.

7. The thickening and filtration process for non-metallic minerals according to claim 1, characterized in that: The drum magnetic separator is a semi-countercurrent type, with the magnetic field strength set at 1500GS.

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