CN103480501A - Phosphate ore floatation method and system - Google Patents

Abstract

The invention discloses a flotation method and a flotation system for flotation and separation of gangue minerals by collophosite. A method for flotation of phosphate rock, comprising performing a cyclone foaming mineralization pretreatment process before the pulp enters the flotation column; the cyclone foaming mineralization pretreatment is to inject the pulp and compressed air into the cyclone along the tangential direction. The cylinder body of the flow foaming mineralization device makes a vortex motion to form a swirling flow, and then the blades in the cylinder are cut and stirred to disperse the air bubbles into the pulp and mineralize it. The cylinder body of the swirl foaming mineralization device is a combination of a hollow cone and a cylinder, the blades are radially distributed in the cylinder body, and the feed port of the swirl foaming mineralization device is along the tangential direction of the cylinder body Set, the discharge pipe is set at the conical end. It can fully disperse the bubbles into the pulp and quickly mineralize them before flotation, avoid the clogging of the foaming device, reduce the height of the flotation column, and create a good separation environment for the flotation process.

Description

A kind of phosphate rock flotation method and system

technical field

The invention relates to a flotation method and a flotation system, in particular to a flotation method and system for flotation and separation of gangue minerals by collophanite.

Background technique

Phosphate rock is an important mineral resource that is indispensable for the production of inorganic phosphate fertilizers and other phosphorus chemical products, but is not renewable and replaceable. China's phosphate rock resource reserves rank among the top in the world, but most of them are low-grade and medium-grade collophosphine that are difficult to select. Only through mineral processing and enrichment can they meet the standards for the production of phosphorus chemical products.

Flotation is the most effective beneficiation method for collophosite. However, the characteristic of collophanite is that the phosphorus-containing minerals are in the form of "colloidal" amorphous fine-grained aggregates closely symbiotic with impurity minerals, and the ore must be ground very finely to dissociate the phosphorus-containing mineral monomers. Fine-grained minerals have small mass and low momentum, and it is difficult to effectively collide with air bubbles during the flotation process, resulting in difficulty in the mineralization of flotation froth; and due to small particle size, large specific surface area, and high surface energy, it is easy Mutual adhesion and agglomeration affect the separation accuracy; moreover, the solubility of fine-grained minerals is high, and the concentration of ions in the pulp is inevitably high, and the chemistry of the flotation pulp solution is complex.

Due to the special characteristics of collophosite flotation, the separation effect of conventional flotation machines is often unsatisfactory. The flotation column has the advantages of simple structure, small footprint, low investment cost, and short construction period. At the same time, it can create a better static separation environment and a certain thickness of flotation foam cleaning layer, which can reduce the influence of the mutual adhesion and agglomeration of ore particles on the separation accuracy, so it has a relatively large development in the treatment of fine materials. space.

However, the existing flotation columns have the following technical problems that hinder their application in collephosite flotation: (1) The flotation columns generally use jets or inflatable foaming devices to generate tiny bubbles required for flotation. For salt minerals with certain solubility such as phosphate rock, under certain conditions during the flotation process, the dissolved mineral components are easy to deposit and attach to the fine nozzles or pores of the foaming device, resulting in blockage of the foaming device and affecting The device is functioning normally. (2) The mineralization of the flotation bubbles is achieved through the countercurrent collision of the bubbles and minerals in the column. Although fine-grained minerals and micro-bubbles have a large surface area, their collision momentum is still small in the static flow environment of the flotation column, and the probability of sticking to each other through collisions to break through the hydration film is small. In addition, the flotation of phosphate rock uses fatty acid collectors, which have relatively poor solubility and dispersibility and flotation selectivity, so that the floatability of phosphate rock itself is not very good, and the impact on the mineralization speed of air bubbles is more obvious . (3) In order to ensure the time required for the mineralization of bubbles, the height of the flotation column is generally relatively high, which inevitably leads to uneven distribution of gas and liquid in the flotation column, the flotation conditions are not easy to control, and the bubbles are easy to float in the floating process. Mergers or ruptures in the middle, resulting in the so-called "turning flowers" and "ditching" phenomena. Although filling the flotation column with an appropriate medium can control the gas-liquid distribution in the column, overcome the merger and rupture of bubbles, and avoid the phenomenon of "turning flowers" and "channeling", but the replacement and maintenance of the filling medium is inconvenient and the passage is easy. Blockage by slime and reduction in the effective volume of the column will also affect the processing capacity of the equipment.

Contents of the invention

The purpose of the present invention is to provide an improved device for collophosite flotation column, which can fully disperse air bubbles into the pulp and mineralize rapidly before flotation, and does not need to go through the mineralization process after the pulp enters the flotation column The flotation can be realized, the flotation speed can be increased, the residence time of the pulp in the flotation column can be shortened, the blockage of the foaming device can be avoided, the height of the flotation column can be reduced, and a good separation environment can be created for the flotation process.

In order to achieve the above purpose, the following technical solutions are adopted:

A phosphate rock flotation method, before the ore slurry enters the flotation column, the mineralization pretreatment of cyclone foaming is carried out; the mineralization pretreatment of the cyclone foaming is to inject the pulp and compressed air into the cyclone foaming The cylinder body of the mineralization device makes a vortex motion to form a swirling flow, and then the blades fixed in the cylinder are cut to make the air bubbles diffuse into the pulp and mineralize.

A phosphate rock flotation system, comprising a slurry mixing tank, a swirl foam mineralization device and a flotation column, the slurry mixing tank and the swirl foam mineralization device are connected through a slurry pump, and the swirl foam mineralization device The discharge pipe is directly connected with the flotation column, and a compressed air inlet is set between the swirl foaming mineralization device and the slurry pump; the cylinder body of the swirl foaming mineralization device is a hollow cylinder with one end open and The openings of the hollow cone with the bottom opening are combined. The blades are fixed and distributed in the cylinder body along the radial direction. Set on the top of the cone cylinder.

According to the above solution, the blades are juxtaposed criss-cross blades.

According to the above scheme, the upper and lower ends of the flotation column are provided with stabilizing plates.

According to the above scheme, there is a flushing water device between the upper steady flow plate and the top of the flotation column.

According to the above solution, a flow diverter device is also provided between the lower stabilizing plate and the bottom of the flotation column to communicate with the slurry pump.

According to the above scheme, the diameter-to-length ratio of the flotation column is 0.2-0.5.

According to the principle of "turbulent mineralization and static separation" of air bubbles and pulp, the invention installs a special swirling foam mineralization device outside the flotation column, and the pulp and compressed air with a certain pressure first pass through the feed pipe along the tangent The air enters the cone-shaped cylinder in the direction of the cylinder, and makes a vortex movement in the cylinder. The air is cut into a large number of uniform and fine air bubbles by the blades distributed in the radial direction in the cylinder, and is fully dispersed into the slurry; the strong turbulence generated by the swirl provides A high-efficiency mineralization method of air bubbles is developed. The dispersed air bubbles have high collision kinetic energy with the ore particles, so they can be quickly mineralized; the mineralized slurry is fed into the flotation column through the discharge pipe of the cone, and then in the flotation column. Static separation is realized in the flotation column.

Beneficial effects of the present invention:

(1) The tiny air bubbles required for flotation are produced by the air that is cut by the blades and does vortex motion quickly. Since there are no small nozzles or pores in the device, there will be no clogging problem; in addition, the air bubbles can be quickly and fully diffused to the Therefore, the gas content in the pulp can be higher, and the flotation conditions are easy to operate and control.

(2) Under the condition of strong turbulent flow, fully dispersed air bubbles and ore particles have high collision kinetic energy, and the mineralization speed is very fast. After the ore pulp enters the flotation column, the mineralized foam layer flotation can be formed immediately.

(3) Bubbles and pulp are first mineralized in a turbulent state in the foaming mineralization device, and then enter the static separation in the flotation column, which is a real process of "turbulent mineralization, static separation" In the separation device, both "turbulent mineralization" and "static separation" are required, and the operating control conditions are contradictory.

(4) After pre-mineralization, the flotation speed of the pulp entering the flotation column is very fast, and the flotation requirements can be met by using a short flotation column, which can not only reduce equipment investment and installation space, but also facilitate equipment operation and control.

Description of drawings

Figure 1: Schematic diagram of the swirling foam mineralization device.

Figure 2: Schematic diagram of the phosphate rock flotation system.

Detailed ways

The following examples further illustrate the technical solutions of the present invention, which are not intended to limit the scope of protection of the claims.

Referring to Figures 1 and 2, the slurry mixing tank 7 is connected to the swirl foaming mineralization device 4 through the slurry pump 6, and the discharge pipe 3 of the swirl foaming mineralization device 4 is directly connected to the flotation column, and the swirl foaming mineralization device 4 is directly connected to the flotation column. A compressed air inlet is set between the mineralization device and the slurry pump; the cylinder body of the swirl foaming mineralization device 4 is formed by combining the openings of a hollow cylinder with an open end and a hollow cone with an open bottom. , the blades 2 are radially distributed in the cylinder body, and may be a plurality of parallel cross blades, the feed port 1 of the swirl foaming mineralization device 4 is arranged along the tangential direction of the cylinder body, and the discharge pipe is arranged On the top of the cone body; the upper and lower ends of the flotation column 5 are provided with a steady flow plate 8, and there may be a flushing water device between the upper end steady flow plate and the top of the flotation column, and the lower end steady flow plate and the flotation column A splitter may also be provided between the bottoms to communicate with the slurry pump.

Referring to accompanying drawing 2, when the phosphate ore flotation system of the present invention is in operation, the ore pulp ground to the required particle size is first fed into the slurry mixing tank 7, and fully interacts with the flotation reagent added in the mixing tank to make the target mineral hydrophobic Then it is transported to the cyclone foaming mineralization device 4 through the slurry pump 6, and then fed into the cyclone foaming mineralization device 4 together with the compressed air at a certain pressure, so that the bubbles can be fully dispersed before flotation In the flotation column 5, the target minerals float up with the air bubbles and overflow from the top to become foam products, and the hydrophilic minerals are discharged from the bottom under the action of gravity to become underflow products. Flotation can be realized after the mineralization process, which greatly increases the flotation speed and shortens the residence time of the pulp in the flotation column, thus reducing the height of the flotation column and creating a good separation for the flotation process. environment. Among them, the pulp pressure is controlled by the pump 6, and its size mainly depends on the specifications of the equipment or the processing capacity of the pulp, but at least it should ensure that the pulp can do vortex motion in the device 4; the air pressure is controlled by an air compressor, and its size mainly depends on the flotation process. The required amount of inflation.

Referring to the accompanying drawing 1, the pulp and air with a certain pressure first enter the cylinder through the feed pipe 1 along the tangential direction, and do a vortex movement in the cylinder, and a plurality of cross-shaped blades 2 fixed side by side in the cylinder cut and compress The air forms fine bubbles and disperses into the pulp. The bubbles collide with the hydrophobic mineral particles at high speed in the vortex turbulent flow to form mineralized bubbles, and then enter the flotation column 5 through the discharge pipe 3.

With reference to accompanying drawing 2, the upper and lower ends of the flotation column 5 are provided with stabilizing plates 8, the purpose is to divide the flotation column into the upper foam zone, the middle separation zone and the lower underflow zone, so as to control the flow of the multiphase flow in the column. state, creating a good static laminar flow sorting environment. Among them, the upper part is equipped with a flushing water device, which can reversely clean the impurities in the mineralized foam, and the lower part is equipped with a diverter device to separate a certain amount of circulating slurry, which can facilitate the adjustment of the slurry level in the flotation column while ensuring the pressure of the slurry pump. the height of.

In addition, the flotation speed of the pulp in the flotation column is fast and the residence time is very short. The flotation column 5 can use a column with a diameter-to-length ratio of 0.2-0.5.

The improved flotation system of the present invention is used for flotation of collophosite in a certain place in Guizhou, the air bubbles are evenly dispersed, the mineralization speed is fast, and the system operates stably. Under the same reagent system and grinding particle size, compared with the conventional flotation column and flotation machine system, not only the separation index is obviously better (see Table 1), but also the collector consumption can be reduced by about 10%.

Table 1 Comparison of indicators of different flotation devices for flotation of a certain place in Guizhou

Flotation device Phosphate concentrate P ₂ O ₅ grade/% Phosphate concentrate P ₂ O ₅ recovery rate/% Sorting efficiency/% improve the system 30.81 82.73 20.73 Conventional Flotation Column System 30.07 79.69 18.51 Flotation machine system 29.62 75.34 16.94

Claims (7)

1. a phosphate rock floating method, is characterized in that ore pulp carries out the pretreatment of eddy flow foaming mineralising before entering flotation column; The pretreatment of described eddy flow foaming mineralising is that the cylindrical tube that ore pulp and compressed air are tangentially injected to eddy flow foaming mineralization device forms eddy flow, then makes bubble permeate in ore pulp also mineralising through the cutting of the blade that is fixedly installed in cylindrical shell.

2. a phosphate rock floating system, it is characterized in that comprising size mixing agitator, eddy flow foaming mineralization device and flotation column, the agitator of sizing mixing is communicated with by ore slurry pump with eddy flow foaming mineralization device, the drainage conduit of eddy flow foaming mineralization device directly is communicated with flotation column, between eddy flow foaming mineralization device and ore slurry pump, is provided with compressed air inlet; The opening part of the hollow cylinder that the cylindrical shell of described eddy flow foaming mineralization device is an end opening and the hollow cone of bottom opening is combined into, blade radially stationary distribution in the cylinder cylindrical shell, the charging aperture of eddy flow foaming mineralization device arranges along cylinder cylindrical shell tangential direction, and drainage conduit is arranged at the cone cylinder top.

3. phosphate rock floating system as claimed in claim 2, is characterized in that described blade is right-angled intersection formula blade arranged side by side.

4. phosphate rock floating system as claimed in claim 2 or claim 3, is characterized in that the upper and lower two ends of described flotation column are provided with stabilier.

5. phosphate rock floating system as claimed in claim 4, is characterized in that, between described stabilier and flotation capital, rinse water arrangement is arranged.

6. phosphate rock floating system as claimed in claim 4, it is characterized in that described stabilier with at the bottom of flotation column between be provided with part flow arrangement and be communicated with ore slurry pump.

7. as claim 2,3,5, the described phosphate rock floating system of 6 any one, the fineness ratio that it is characterized in that described flotation column is 0.2-0.5.

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