froth flotation equipment for sale

froth flotation method - jxsc machine

froth flotation method - jxsc machine

The Froth Flotation Method is means separating minerals according to their different physical and chemical properties. According to classification, the flotability of gold and silver minerals is included in the first category of natural and non-ferrous heavy metal sulfides, characterized by low surface wettability and easy flotation, which can be flotation by xanthate collectors.

The froth flotation method is widely used to treat various veins of gold and silver ores for the following reasons: (1) In most cases, the froth flotation process can enrich gold and silver in sulfide concentrate to the greatest extent and discard a large number of tailings, thus reducing the smelting cost. (2) When the flotation machine is used to treat polymetallic gold and silver ores, concentrates containing gold, silver and non-ferrous heavy metals can be effectively separated, which is conducive to the comprehensive utilization of valuable mineral resources. (3) For refractory gold and silver ores which cannot be treated directly by mercury amalgamation or cyanidation, a combined process including flotation is needed. However, there are some limitations in flotation, such as ores with gold particles larger than 0.2-0.3 mm or pure quartz gold ores without metal sulfides, which are difficult to deal with by flotation separation alone.

flotation machines & flotation cells

flotation machines & flotation cells

In small plants, it is common practice to include conditioners following the last stage of grinding. Additional conditioners are normally required between flotation operations which produce individual mineral concentrates. Each conditioner stage should consist of a minimum of two separate agitated tanks. Provision must be made to drain and clean conditioner tanks to appropriate flowsheet locations. This is particularly important in the case of conditioners which follow the grinding circuit since these tanks tend to accumulate oversize material produced during grinding circuit upsets.

Conditioners provide positions in the plant flowsheet wherein changes to the ore slurry are brought about by the addition of reagents and pH modifiers. Conditioners must always be designed to provide adequate time for chemical or physical changes induced by reagent additions to proceed to completion. Conditioners also serve a useful function in that swings in ore grade, particle size distribution, or other flotation variable tend to be partially homogenized and dampened during the conditioning unit operation. For example, in small installations it is not unusual to experience wide swings in feed grade. The conditioning unit operation provides the operator an opportunity to modify reagent additions in order to maximize recovery during periods of process instability. If possible, conditioner tanks should be arranged in tiers so that slurry overflows between sequential tanks under the influence of gravity.

The selection of flotation cell size and configuration can have a substantial influence upon installed cost and can contribute to operational efficiency. Two possible flotation configurations for a 500 metric ton per day installation are presented in Figure 5. The computational basis assumes 30 percent solids in rougher flotation, 20 percent solids in cleaner, recleaner and cleaner-scavenger flotation, a ratio of concentration in rougher flotation of 3.07 an overall ratio of concentration of 5.0, and an ore specific gravity of 2.9. This representation indicates that the flotation bay layout employing the larger flotation cells, in this case 2.83 cubic meter (100 cubic feet) machines, occupies less area and reduces installed capital cost by about 25 percent. However, there are instances when the first illustration (selection of small flotation cells) would be chosen for reasons of compactness and symmetry.

Complex multiple product flotation installations usually require a high degree of sophistication regarding operational control. Many times, in small flotation concentrators this level of sophistication is not available. If the facility is located in a remote area, experienced operational personnel may be impossible to acquire. Consequently, the flotation circuits should be as simple as possible. For an installation producing a single mineral product, the flotation scheme illustrated in Figure 6 is recommended. This system, which is compatible with configuration 2 on Figure 5, is simple to operate and eliminates the build-up of a large circulating load of scavenger concentrate. This system is also flexible in that various produced concentrates can be subjected to regrinding should changes in mineralogy or primary grind so dictate.

It must be recalled that the weight of rougher and cleaner concentrates produced from high-grade ores can be substantial. Provision to remove froth by the use of froth paddles on all flotation cells should be included in the original design. The additional capital cost required for froth paddles is a reasonable investment since these devices tend to negate errors in flotation pulp level or frother addition. The open circuit flotation system presented can be operated by individuals having minimal training. The advice of Taggart regarding the inclusion of a small pilot table as a visual sample on rougher tailings is still legitimate.

In almost all new flotation installations, the use of launders fabricated from sheet rubber is recommended. Care must be taken to insure that all launders are sloped properly. In addition, launders must be provided with appropriate sprays and sluice lines to facilitate concentrate transport. The launder water system must be carefully designed to insure functionality without excessive concentrate dilution.

In recent years it has become popular to use vertical pumps for both concentrate and tailing transport in smaller circuits. It is usually possible to employ only one, or at the most two, pump sizes for all of the required flotation pumping installations. The same size vertical pump may also be used in various locations about the plant for cleanup duty. The usage of vertical pumps reduces seal water requirements, and eliminates concrete pump bases, fabricated sumps, and the valving associated with horizontal pumps.

For the past 35 years Sub-A Flotation Machines have been serving faithfully in all parts of the world. Anniversaries of progress such as this make reminiscing very interesting and we thought you would enjoy seeing some of the Firsts in the flotation machine industry as pioneered by the Sub-A.

1928was a pioneer in the use of V-belt drives in the flotation industry. This high-head machine also had wide-spaced greaseless lower bearings. At one time this was the largest flotation machine in the world.

1930 First steel tank flotation machine. Earlier machines had wood tanks. Steel tanks met great opposition at first, later became standard. This high-head, all-steel Sub-A marked the introduction of anti-friction lower bearings.

1932 First low-head flotation machine marked a radical departure from the then accepted principle that the space between bearings must be greater than the distance beyond the lower bearing. This machine was of the cell-to-cell pulp flow design and used a quarter-turn flat belt line-shaft drive.

1933 First steel tank low-head, low-level flotation machine. It had an individual motor and a V-belt drive. This design became very popular with mill operators and thousands of cells were sold similar to those pictured above.

Laboratory Flotation Machines have made progress, too. In our early days the cast-iron tank machine with its round-belt mule drive was the latest word. Contrast it with todays modern Sub-A Laboratory Flotation Machine with its heavy glass tank and stainless steel parts.

1961 Todays demands for Sub- A Flotation Machines keep our modern factory busy. Today more Sub- A Flotation Machines are specified than all competitive makes and is the unquestioned First Choice in Flotation.

vertical froth pumps - sala type

vertical froth pumps - sala type

Froth pumps are vertical shaft slurry pumps with integral sumps generally used on the output from froth flotation cells. Centrifugal pumps cannot pump froths, and therefore require sufficient volume in the sump to hold the froth until broken down to a liquid. The froth is broken down by being sheared in the sump either by reverse swirl spirals at the entrance to the pump, or by mechanical agitators on the pump shaft, or by use of water sprays. To provide enough volume within the sump for froth retention, a froth application factor is applied for pump sizing. This factor is higher the more stable the froth and is multiplied by the flow rate to size the unit. However, power is calculated from the liquid flow rate. Froth factors can generally be estimated only from experience with the slurry and must be supplied by the user.

Froth pumps have been used as general slurry pumps that are self-regulating, in that when the sump empties, the pump partially air locks until the level in the sump rises again. The cantilevered shaft design limits the head that can be generated.

small flotation machines

small flotation machines

These ALL STAINLESS STEEL flotation machines are used to form banks of 2 cells. The can be arranged in series to accommodate small plants of up to 1 TPH (24 Ton/day). View the description below for a flotation cell capacity table you can use to estimate how many machines you need.

Look at the capacity you need in KPH (kilo/hour) or TPD (ton/day) and look for a number of machines, ideally, between 2 and 8. From this, select what cell size (volume) gives you that quantity of machines to form your flotation bank and circuit.

FX Model Continuous Mechanical Flotation Machine is applicable to separation of minerals with float-free method in labs. It is a unit of several combinations of two cells with number of the cell being even, varying from two to ten cells. Left or right type flotation machine can be supplied as required by customer.

To adjust the level of slurry in the cell and the thickness of the scraped froth layer, use wall plates of the two cells to make intermediary cell;install slurry level regulator; and mount orifice plate onto the cover in the cell to avoid negative effects on the froth zone exerted by the chaotic motion of slurry, as well as to avoid the gangue from being taken into the concentrate by the machine.

Lining plates are installed at the cell so that the bottom of the cell will not be abraded. The lining plate can be replaced. On the outside of the cell bottom is a discharge mouth, which is used to discharge water during its cleaning. The slurry flows through the overflow mouth of wall panel into the intermediary cell and tail cell. It flows to the lower part of the intermediary cell and the duct covered by the lower part of the cell wall and then to the next cell. In this way, it can continue to flow through all the cells of flotation machine. It flows from the feed cell and is discharged from the discharge mouth of the tail cell. The front and back of the lower part of the cell is installed feeding mouth, to make it easy to change the process flow.

The impeller system is a disk impeller which is installed in the center of the cell in the flotation machine and whose blades are radially arranged. It is fixed onto the lower end of the impeller shaft and revolves around the vertical shaft pipe.

The upper end of the pipe lies above the pulp stone and the froth layer while its lower end is supported on the cover. When the impeller rotates, a large amount of air can be sucked along the vertical pipe. Below the cover is fixed protective disk. The gap between the safety disk and the impeller depends on the amount of sucked air. It can not be larger than 3mm at most. When the gap is too large, replace the abraded protective disc and make appropriate adjustment.The holes in the vertical pipe are used to circulate slurry as well as mix the slurry and air. The rolling shaft installed inside the bearing shell above the impeller shaft rotates. The bearing shell is installed on the crossbeam and belt pulley is fixed on the top of the shaft which rotates through the V-belt when the motor is turned on. The tension of the V-belt is adjusted through the nuts.

The froth is scraped along the flotation machine through rotary scraper. The scraper is installed outside the discharge mouth of cell. At one end of the scraping shaft is installed belt pulley which rotates through the drive of worm reducer and V-belt.

laboratory flotation machine

laboratory flotation machine

Flotation utilizes the fact that the metalliferous ore particles, and the gangue minerals have different interactions with water. Fundamentally floatation relies on the fact that hydrophobic ore particles and hydrophilic gangue particles can be separated. Hydrophobic means water fearing and hydrophobic substances fundamentally repel water. Hydrophilic means water loving and layers are attracted to water. In floatation, we create bubbles as a froth that sits on the top of a suspension of crushed ore. The hydrophobic ore particles which dont want to stay in the suspension, preferentially petition to the surface of the bubbles. While the gangue minerals which are happy to stay in the suspension stay in the water below the froth and sink to the bottom. If the froth is continually replenished, then the ore particles float to the surface in the froth which can be skimmed off and the ore particles recovered. To enhance the formation of the froth we had chemicals called frothers, which are surfactants like detergents which help to create small bubbles and stable froth layer at the surface. There are our basic types of floatation cells: Mechanical; column; Jameson and reflux floatation cells. And there are many variations on these basic themes well have a look at the simplest of these the mechanical floatation cell.

Mechanical floatation cells consist of a sturdy tank air is sucked in via a simple motor shaft and the spinning in power extra break the gas into fine bubbles as well as to get the solid particle suspended. The bubbles will rise to the surface forming a froth layer, hopefully carrying the hydrophobic ore particles with them. This froth overflows and is collected as the concentrate. Water results are withdrawn from the base of the cell to remove the uncollected solids in a tailing stream. We can wash the entrain gangue mineral from the froth layer via the wash water.

Coal is somewhat naturally hydrophobic, and so it can be readily floated. However, most mineral ores are naturally hydrophilic. What makes floatation such a powerful tool for mineral processing is that we have learnt how to selectively modify the surface properly through different ore minerals to make them hydrophobic. We use various types of chemicals, remembering that we have already spoken about frothier. But theyre also collectors, activators, and depressants to control the particle surface properties.

A collector makes the surface of a particle hydrophobic. An activator makes the particle surface more responsive to the collector. A depressant makes the surface of unwanted particles less responsive to the collector, we can also add acids or bases as pH modifiers to control the responses of minerals to the collector. Flotation has the capacity to recover at different mineral species at different stages in the process. In this way we can beneficiate complex mixtures of ores, to produce a range of different mineral products. To illustrate the power of the flotation process, consider this sample of low grade copper rock. If this copper is crushed to produce a clean stream for flotation process, we end up with the powder that looks like this. After flotation, we produce a stream of tailings that looks like this and a stream of recovered ore that looks like this.

Flotation is a powerful tool to recover small amounts of valuable minerals from low grade ores. So having generated your product the next task is to get it to the customer, well take a look at how this is done in the next topic.

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