A worthy headbox of dual-pressure zone thickener

 The double-pressure zone thickener is mainly used for the washing and concentration of the slurry in the waste paper deinking and reducing treatment system. The machine is mainly composed of active rollers, driven rollers, and endlessly woven filters and flow boxes running around two rollers. , Discharge screw conveyor and other components. The slurry passes through the headbox, which is dewatered by the squeezing action between the filter screen and the active roller in the nip between the filter screen and the active roller. The active roller is engraved with deep grooves, which can obtain a high nip pressure, so that the slurry is concentrated on the inner surface of the mesh into a form of slurry strips. These strips are kept on the filter screen. When the slurry enters the filter In the nip between the net and the movable roller, it will be further dehydrated and then separated from the net surface, falling onto the roller surface and being scraped off and discharged by the scraper. The concentration of the slurry discharged by the machine is constant, and the discharged slurry will be transported away by a screw conveyor, and the removed white water containing ink particles and fillers will be discharged from the bottom of the white water tray.

The double-nip thickener is favored by users because of its good performance, but with the continuous expansion of the wide screen of the filter screen, major problems have become more and more serious; one is the thickness of the slurry layer on the entire web is inconsistent, and the slurry concentration is uneven; the other is The filter is easy to run off, causing the filter to tear. But this will bring great economic losses to the enterprise.

For the problems of the double-pressure thickener, the reasons are as follows:

1. At first, I suspected that the quality of the filter was not good enough; after consulting with the manufacturer of the filter, it was required to strictly follow the technical requirements of the filter. After many experiments, it was proved that the tearing of the filter was not caused by the quality of the filter itself.

2. The sensitivity of the deviation adjustment mechanism is not enough, and the deviation signal cannot be transmitted in time, which will cause the movement of the deviation adjustment motor to lag. By replacing several sets of new control modules, the test is carried out quickly, the deviation adjustment signal is transmitted in time, and the deviation adjustment mechanism moves quickly. The tearing of the filter has little to do with this item.

3. If the machining error of the worm and connecting rod of the two worm gear boxes is too large, the transmission will not be in place and the deviation can not be corrected. Through machining a higher precision worm and connecting rod, the phenomenon of deviation of the filter screen will also occur.

4. If the coaxiality of the two transmission rollers processing fails to meet the requirements or the installation axes of the two rollers are not parallel, vibration will occur, which will cause the filter screen to jump and cause deviation. Re-adjusting the installation accuracy of the two rollers, the effect is still not satisfactory.

It may also be the problem of the headbox. The function of the headbox (1) is that the slurry that is sprayed is evenly distributed along the horizontal direction of the active roller; it effectively disperses the fibers and improves the uniformity of the slurry layer; the spraying is stable. If the pulp output from the headbox is not uniform, the pulp concentration will be uneven, and the filter screen will run off and cause tearing. Therefore, improving the design of the headbox structure is a key issue to solve the problem of the dual-pressure thickener.

After the improvement of the headbox, there are mainly several aspects:

1. In order to ensure that the pressure of the slurry flowing through each section along the way is the same, the sizing main pipe is designed into a square cone pipe with a smaller and smaller cross-sectional area.

2. In order to facilitate the hole arrangement and keep the direction of the slurry flow at the end of the main pipe unchanged, a rectangular tapered pipe of equal width will be used, and the "height ratio" at the entrance is 1:2~3.

3. The main pipe should facilitate the incoming slurry to change the direction of slurry flow. A transition pipe is set between the main pipe and the slurry inlet pipe, and the circular slurry inlet pipe is gradually changed into a rectangular main pipe. The final wall of the slurry inlet pipe and the square cone pipe should be on a horizontal line.

4. Equipped with a return pipe. The function of setting backflow is mainly to ensure the stability of the slurry flow pressure in the branch pipe and the uniform distribution of the slurry. At the same time, there is no dead corner at the end of the cone pipe to prevent the slurry clusters from gathering, expel air bubbles, and play a cleaning role.

5. The main pipe is made of stainless steel, and the inner wall is processed smoothly, without grout or rust. In order to ensure that the main pipe is not deformed, reinforcing ribs are arranged on both sides of the outer wall of the main pipe to make the main pipe have sufficient rigidity.

6. Ensure that the center of gravity of the headbox is on a straight line, which is more conducive to the stability of the headbox.

After the improved design of the headbox, the thickness of the slurry layer on the entire web is uniform, the slurry concentration is basically stable, the service life of the filter is greatly improved, the maintenance cycle of the equipment is reduced, the cost is correspondingly reduced, and the production efficiency of the enterprise is improved.

https://www.fat-tonys-pizza.de

A new type of thickener-lifting thickener

 Thickener is a continuous working thickening and clarification equipment, mainly used in the dehydration of tailings slurry in wet beneficiation operations, and also widely used in the thickening and purification of solid-containing slurry such as steel and sewage treatment. According to its driving mode, the thickener can be divided into two categories: peripheral drive thickener and central drive thickener. Peripheral drive thickeners have integral rake lifts to varying degrees, especially the secondary rake in the cone pit. , It will cause the defects of pressure rake. Although the central drive thickener can lift the rake, when the load-bearing bridge is too heavy or the central drive torque is too large, a new type of thickener-automatic rake thickener appears.

When the thickener is working, the motor, reducer and drive transmission equipment rotate along the thickening tank, the transmission device will drive the central support through the transmission bridge and the central support, and the rotating support will drive the sliding frame through the sliding key , The sliding frame is connected to the rotating cage, and the long and short handles and the vice handles are driven by the rotating cage. The rake teeth of the long and short rake racks will scrape the sedimentation material in the thickening tank into the cone pit of the thickening tank, and the role of the vice handle will prevent the cone. The underflow material in the pit is consolidated to ensure the smooth flow of underflow sludge.

When the material settled to the bottom of the thickening tank increases, when the bed layer thickens, the working resistance of the rake will increase. When the working resistance is adjusted to a set value, the transmission device will stop rotating and the rake cylinder will be lifted. Drive the sliding frame, the whole will be lifted up, and the working resistance will be reduced subsequently, but if it is reduced to a certain level, the rake will not be lifted, and the rake frame will stay at this height for rotating work until the lowest When the working resistance increases to the set value again, the rake frame will be raised again, repeating the action, so as to achieve the purpose of automatically raising and lowering the rake.

Peripheral transmission automatic rake-lifting thickener includes transmission device, center support, transmission bridge frame, rotating cage, long and short rake frame vice handle, distribution device, trough frame, hydraulic system, electronic control system, etc.

(1) Transmission device.

The transmission device can be driven by a motor reducer or a sub-motor. The transmission mode can be a rubber wheel, a knurled wheel or a gear drive to meet different work needs.

(2) Center support

The central support is a composite structure, composed of a fixed support, a sliding frame, a rotating bracket, and a seat ring. The transmission device drives the central support to rotate through the rotating bridge frame. When the rake is lifted, the hydraulic cylinder will lift the central support sliding frame to make the whole Lifting, so that it can not only show the driving torque, but also can lift part of the lifting according to needs, the structure is more novel.

(3) Transmission bridge

One end of the transmission bridge is connected with the central support rotating bracket, and one end is connected with the transmission device. However, because the central support adopts a specific device, the bridge does not move laterally with the lifting part of the thickener, which prevents the transmission device from being in the center. It can increase the axial force generated when part of the lifting, avoiding the phenomenon of rubber wheel degumming. Determine the transmission mode and other transmission modes.

(4) Extraction of automatic rake signal

There are two ways to extract the rake signal of the thickener. One is an independent mud control resistance detection device. It is mainly composed of force measuring box and sensor. The force measuring device is installed on the mud scraper near the cone pit. During the operation of the equipment, the force receiver directly contacts the deposited sludge. During the operation of the equipment, the force receiver directly contacts the sludge. The resistance during mud scraping is transmitted by the secondary instrument to the PLC controller of the control system. A pressure sensor, hydraulic pump and various control valves are installed in the hydraulic pump station. The mud scraping resistance is detected by the pressure sensor. The hydraulic signal will be converted into an electric signal, and the PLC program controller will issue an instruction, so that the rake lifting cylinder can move and realize automatic rake lifting.

(5) Cloth device

Ordinary center drive thickener feeds the material directly from the center of the pool. The particles in the slurry can’t settle sufficiently. The sedimentation layer that has been deposited is destroyed due to the erosion of the liquid flow, and the material that has been deposited is removed. Rushing affects not only the concentration of overflow water, but also the sedimentation effect of particles.

The peripheral drive center automatic rake-lifting thickener combines the advantages of a peripheral drive thickener and a central drive thickener. This machine not only has the advantage of large transmission output torque of the peripheral drive thickener, but also has the central drive thickener that can lift the rake as a whole It also avoids the thickening machine from being too bulky. Therefore, the large-scale and intelligent thickening machine can be realized, which is a direction of the thickening machine.

http://centrumpelplin.pl/

How to use inclined plate thickener for tailings dry discharge

 Tailings treatment is an important part of mine production. Concentration in dry tailings discharge is an important link in achieving dry stacking. It not only directly affects the processing capacity of filter equipment, but also affects the resistance of filter cakes. The particle is resistive to the filter cake, so according to the characteristics of iron tailings, there is a new type of thickener.

The flow of tailings slurry in the thickener is ideally slow. As soon as the solid particles leave the flow layer, they will be considered as sediment. This model is also called shallow sedimentation. The sedimentation occurs in the void between the inclined plates. Within the cavity, but due to the small spacing between the inclined plates, it creates favorable conditions for the formation of laminar flow. The clarified overflow water moves upward along the inclined plate space, and the solid particles settle between the two plates, and only need to settle to a small distance to fall on the plate, and then slide down the inclined plate to the compression port for compression and dehydration , The final height will be discharged from the bottom discharge port. According to the difference between the feeding direction and the sedimentation direction of solid particles in the inclined plate thickener, it can be divided into upward flow and downward flow. Three types of lateral flow.

(1) Upward flow means that tailings slurry is fed from the lower part, the sediment is discharged from the lower part, and the overflow is discharged from the upper part;

(2) Downward flow means that tailings slurry is fed from the upper part, the sediment is discharged from the lower part, and the overflow is discharged from the lower part;

(3) Lateral flow means that tailings slurry is fed in from one side, sediments are discharged from the bottom, and overflow is discharged from the other side.

Since the concentration of iron tailings is generally low, the thickener is equivalent to a clarification device. Its sedimentation area can be calculated based on the rising speed of the clarified water in the thickener and the sedimentation speed of the finest particles in the material to be recovered. 

The inclination angle of the inclined plate is also an important concentration parameter. The sum of the area of ​​the thickener is the sum of the horizontal projection area of ​​each layer of the inclined plate. In a certain range, when the inclination angle is less than a range, the relative sedimentation velocity of solid particles will be reduced, and the liquid flow between the inclined plates will be affected. In order to work normally, the solid particles falling on the inclined plates can flow by themselves. The discharge angle cannot be too small. So choose 45 degrees-60 degrees.

The spacing between the plates has a great influence on the concentration effect. When the distance between the plates is small but the production capacity is the same, the size of the thickener will be too small. The distance between the plates is small, and a large number of inclined plates can be accommodated on the same level, which can help increase the sedimentation area of ​​the thickener. However, if the board spacing is too small, the surface of the inclined board will rub against the fixed particles that have fallen on the board from sliding down, and bring certain difficulties to the use and maintenance of the equipment.

The core key to the promotion and application of inclined plate concentration equipment lies in the material selection and production of the inclined plate. The range of material selection is relatively wide, and the best can be selected according to the conditions of use. Board materials with the characteristics of chemical stability, sufficient strength, light weight and cheapness, non-toxicity, smooth surface, good hydrophobicity, antistatic, and aging resistance can all be used.

If the conditions of use allow, the length of the inclined plate is longer to increase the unit footprint of the thickener.

At the same time, in order to ensure that the material can be evenly covered in the width direction and to avoid the deflection and deformation of the board surface in normal work, the width of the board should not be too large, usually no more than 0.8 meters.

Do you know the vibration device of the thickener?

 The thickener is a solid-liquid treatment equipment used in the concentrator. In order to improve the treatment effect of the thickener per unit area and improve the efficiency of the thickener, the high-efficiency thickener or the inclined plate thickener will be selected. High-efficiency thickeners will increase the height of the straight wall section of the thickening tank, and use appropriate fabrics to add flocculants to improve concentration efficiency. In some concentrators, the materials are small and viscous, the sedimentation speed is slow, and the flocculant cannot be used due to the nature of the material. At this time, the inclined plate thickener is used. The thickening pool of the inclined plate thickener will be divided into a number of equally divided sectors, and each sector will be arranged at a certain interval into a certain angle of inclined plate or inclined tube. The fine particles of the material in the lower part of the thickening tank will naturally settle on the inclined plate and the inclined tube. In this way, the settling distance of the material particles can be shortened by the inclined plate or the inclined tube, and the settling time can be reduced to increase the thickener. The precipitation area to improve concentration efficiency.

The inclined plate thickener will be affected by the nature of the material and the material of the inclined plate during use, and the phenomenon of adhesion between the inclined plates will often occur, which is what we often say that the material that settles on the inclined plate or the inclined tube is not Continuous sliding, on the contrary, the material will settle to a certain thickness before the whole fall. This phenomenon is commonly called hanging material. The whole falling material will be filled with the cone pit of the thickening tank, but because the thick material is too thick, it will cause the harrowing phenomenon after the lifting device fails. There may even be a phenomenon that the inclined board or the inclined board collapses. When the inclined plate thickener has material hanging, the user will use high-pressure water flushing to solve the problem. During the reprocessing process, the overflow water of the thickener will run off and the thickener will stop to clear the pool, which will affect the thickener. Normal use.

In response to this situation, a vibration device for the inclined plate thickener was designed. This vibration device is not only suitable for ordinary central drive thickeners, but also for high-efficiency deep cone thickeners and other types of inclined plates or inclined tubes. Thickener.

The vibration device is generally composed of a vibration rod, a connecting rod, a vibration ring and an electric control box. The vibrator consists of a vibration motor and a motor frame. Composed of shock-absorbing spring and support frame. When installing the vibrator, the support in the vibrator is placed on the bridge of the thickener on site and adjusted to a suitable place for fixing. The lower part of the connecting rod and the vibrating ring can be fixed with bolts. The connecting rod, the motor frame and the vibration ring will be rigidly connected. In order to reduce the impact of the vibrator on the bridge frame of the thickener during the working process, a shock-absorbing spring can be used between the vibrator and the bridge frame to relieve the high-frequency excitation generated by the vibrator Vibration of the force on the bridge.

When the inclined plate vibration machine is working normally, the thickener enters the lower part of the thickening tank from the feeder. The coarse particles in the incoming slurry naturally sink, and the fine materials in the lower part of the thickening tank will naturally sink into the cavity of the inclined plate, but due to the small distance between the inclined plates, the particles only need to settle a small distance , You can settle on the inclined board.

The installation structure of the vibrator device is very simple, easy to install, and reliable in operation. It is very suitable for the beneficiation method where the material is small and thick, the speed is very slow, and it is not easy to fall off. The vibration device can be used for power-driven thickeners equipped with inclined plates or inclined tubes. This vibrating device has a certain reference effect for the technical reform of the new thickener and the technical improvement of the old inclined plate.

What factors can cause the flotation machine to not work normally?

 The flotation machine is a full-grain flotation machine, suitable for both coarse and fine particle separation. After the Chinese pulp of the GLF flotation machine is processed, the flotation machine must be agitated and aerated, so that the mineral particles can be fixed on the bubble and float to the surface to form a foam product, and the rest will be stored in the pulp for separation . The GLF flotation machine is not only a stirring device, but also capable of forcibly blowing in air under the external special action. The mechanical stirring device is used to agitate the slurry to distribute the air flow, and the aeration and stirring of the slurry work separately. The GLF type aerated stirring flotation machine can be adjusted according to its own needs at best. Only in this way can it be helpful to improve the sorting capacity and processing capacity of the flotation machine. However, due to the larger processing capacity and the shallower flotation cell, the required power consumption is lower. GLF flotation opportunities because the impeller speed is low, the concentration of the slurry when passing through the impeller will also be lower, and the ore particles will become finer, which will correspondingly reduce the efficiency of flotation. In this case, the impeller and stator will reduce wear. There is a grid plate in the flotation tank, which will cause a suspended layer of coarse particles, which can make the surface of the slurry more stable and make the technical performance better. In this case, it is beneficial to the coarse particle flotation.

There are several common faults of GLF:

(1) The cover plate or stator screw of the flotation machine is off.

During the entire operation of the flotation machine, the cover plate and screws will easily fall off due to the rotating impact and vibration of the flotation machine itself. This situation will affect the normal operation of the flotation machine. Therefore, the flotation machine is carefully checked before each work.

(2) The bottom of the flotation machine is worn.

If the flotation machine runs for a long time and rotates strongly, the bottom of the tank will be worn and thinned, and the surrounding guard plate will be worn and deformed, and under the action of the flotation agent, the bottom of the tank will also be worn and deformed. Therefore, when wear occurs, It is necessary to repair welding in time.

(3) Pry up the bottom guard plate of the groove.

During the flotation process, the tank bottom guard plate protects the bottom of the tank. When the impeller rotates strongly, the circulation of the ore in the flotation tank will be accelerated. In severe cases, the charge will increase and the guard plate will be pryed. It will cause an accident.

(4) Wear and corrosion of impeller and cover plate.

The impeller and cover plate are the core components of the flotation machine, and it is also a position that is easy to wear. It is directly related to the degree of aeration of the slurry during the flotation process. The degree of agitation in the sea area, but because the flotation machine is in the process of long-term work, it will The impeller also damages the cover plate, so the impeller and cover plate need to be repaired and replaced for a long time.

(5) The spindle is worn out.

When the spindle is in use, the rubber sheath of the spindle should be protected. After the rubber sheath is worn, the spindle wears quickly under the action of the internal circulation of the slurry, and it is very easy to break the shaft. Therefore, it should be updated frequently during the inspection. Rubber sheath.

(6) The bearing clearance becomes larger.

When the main shaft of the flotation machine is running at high speed, the bearing gap will easily become larger, which will damage the bearing. At this time, only the tightness of the inner and outer gaskets of the bearing needs to be adjusted.

(7) The motor generates heat.

During the operation of the flotation machine, too much sand accumulates in the flotation cell, the cover plate and the ore tube fall off, and the circulation of the ore tube is too large, which will cause the electric heater to heat up. In this case, the cover plate and the ore tube should be provided. Tighten it in time when it is loose, and replace it in time when the circulation volume of the ore pipe is too large.

    As mentioned above, during the use of the GLF flotation machine, due to the harsh environment and poor maintenance during use, various problems will occur. Therefore, timely attention and regular maintenance should be carried out to prevent the work process from being blocked. Off.

How to use large flotation machine to separate copper and molybdenum ore

 About 90% of non-ferrous metal recovery in the world will use flotation method, in order to realize mineral flotation flotation machine plays a great role. Large-scale flotation machine can significantly improve the processing capacity of beneficiation, reduce consumption, and obtain higher benefits.

The flotation machine is a motor that drives the rotating shaft to rotate the impeller. Under negative pressure, the pulp moves between the impeller and the stator, and the centrifugal blower is evenly dispersed in the air through a porous cylindrical air distributor for mineralization. After the stator is stabilized, it rises to form a stable foam layer, and enters the next operation through the upper foam tank. The remaining slurry will flow through the flow holes in the tank wall to the next tank for sorting, and finally become tailings.

The main characteristics of tooth decay of the super large flotation machine are:

(1) The pulp aeration and bubble mineralization effect is good.

The air coming in from the blower will directly enter the air inlet on the top of the flotation machine through the air duct. A regulating valve that controls the air volume is installed at the air inlet. The air can directly enter the hollow shaft to ensure that the slurry in the flotation machine is not fully affected by the equipment. Mineralization. And a good amount of aeration can effectively suspend the mineral particles in the entire flotation tank and evenly distribute the bubbles.

(2) Energy saving and loss of equipment.

Before the flotation machine, air was directly fed between the impeller and the stator by the blower. After the hollow shaft rotates, the equipment can make the air into the suspension state formed after stirring at low speed and enter the selection for selection. The stator adopts The form of low damping changes the direction of the slurry flow to the radial direction, which can reduce the resistance circulation and power consumption of the slurry.

(3) High efficiency of automatic liquid level control. The slurry level in the flotation machine can be detected by a slurry level gauge, which can realize automatic control of the slurry level. The tailings box and the middle box have a cone valve to control the flow of the slurry, which is controlled by a pneumatic actuator, so that it can be used for full adjustment of the slurry.

(4) Conducive to improving the selection effect. The deep cone structure can mineralize the pulp to provide a stable foam zone and a longer separation zone, so that low-pressure air can be fully dispersed in the solid, liquid, and gas three-phase strong turbulent mixing zone at the bottom of the flotation machine, which can generate bubbles If it is fully utilized, there is a large speed difference between the bubbles and the pulp. There are more opportunities for fine particles to contact the bubbles, and the fine particles will fully float out. The slurry will sink, increase the chance of collision of bubbles and increase the chance of flotation.

(5) Convenient operation and management of equipment.

Can drive the load to start; advanced slurry level control olefin; reduce short circuit circulation; spare parts wear light, low maintenance and repair costs; simple structure, easy maintenance; low energy consumption; good air dispersion; low chemical consumption, saving investment and so on.

Research on unit consumption and service life of ball mill liner

 The liner is a key easily damaged part for the ball mill. The unit consumption and service life of the liner are inseparable from the working efficiency of the ball mill.

     The factors that affect the wear rate of the liner mainly include the corresponding particle size and hardness of the material to be ground, how much electricity is needed to grind each ton of material, the diameter of the mill and its speed, the structure of the liner and the wear resistance of the liner material The percentage of the weight and volume of the original lining board and the original lining board. For the current process, the metal liner is mostly low-grade ore first-stage grinding, but for most low-grade ore, the content of silica and other hard grinding and corrosive minerals are very high, but in this case In the second-stage grinding process, many concentrators will choose ball mills to use rubber liners.

     The service life of the cylinder liner is four factors: macroscopically speaking, the resistance to impact failure damage; macroscopically speaking, the resistance to fatigue failure damage; the resistance to surface cutting or cutting wear; the surface microscopic resistance to impact fatigue and wear Kind of operating conditions.