Flotation concentrates

Pressure filters can treat feeds with concentrations up to and in excess of 10% sohds by weight and having large proportions of difficult-to-handle fine particles. Typically, slurries in which the sohd particles contain 10% greater than 10 ]lni may require pressure filtration, but increasing the proportion greater than 10 ]lni may make vacuum filtration possible. The range of typical filtration velocities in pressure filters is from 0.025 to 5 m/h and dry sohds rates from 25 to 250 kg nY/h. The use of pressure filters may also in some cases, such as in filtration of coal flotation concentrates, eliminate the need for flocculation. 

The KDF Filter. The KDP filter (Pig. 23) (Amafilter, Holland) is based on the same principle as disk filters. It was developed for the treatment of mineral raw materials, like coal flotation concentrates or cement slurries, and can produce a filter cake of low moisture content at very high capacities, up... 

The basic flow sheet for the flotation-concentration of nonsulfide minerals is essentially the same as that for treating sulfides but the family of reagents used is different. The reagents utilized for nonsulfide mineral concentrations by flotation are usually fatty acids or their salts (RCOOH, RCOOM), sulfonates (RSO M), sulfates (RSO M), where M is usually Na or K, and R represents a linear, branched, or cycHc hydrocarbon chain and amines [R2N(R)3]A where R and R are hydrocarbon chains and A is an anion such as Cl or Br . Collectors for most nonsulfides can be selected on the basis of their isoelectric points. Thus at pH > pH p cationic surfactants are suitable collectors whereas at lower pH values anion-type collectors are selected as illustrated in Figure 10 (28). Figure 13 shows an iron ore flotation flow sheet as a representative of high volume oxide flotation practice. 

The abundance of indium in the earth s cmst is probably about 0.1 ppm, similat to that of silver. It is found in trace amounts in many minerals, particulady in the sulfide ores of zinc and to a lesser extent in association with sulfides of copper, tin, and lead. Indium follows zinc through flotation concentration, and commercial recovery of the metal is achieved by treating residues, flue dusts, slags, and metallic intermediates in zinc smelting and associated lead (qv) and copper (qv) smelting (see Metallurgy, EXTRACTIVE Zinc and zinc alloys). 

Sizing. In most flotation plants, flotation concentrates, after being dried, are sized into three fractions and each serves a specific agricultural market. The fractions are coarse-, standard-, and suspension-grades of muriate of potash. Typical screen analyses are presented in Table 6 other physical characteristics are summarized in Table 7. 

The flash roaster is flexible ia handling various flotation concentrates and reaching the degree of desulfurization desired, ie, 0.5—3.0% sulfate sulfur. Waste heat is easily recovered. However, grinding and rabbling must be done mechanically. 

CMC), reverses the effect that the surfactant has on contact angle at lower concentrations, and at or above the CMC there is no further lowering of surface tension. At the higher concentrations, the surfactant loses some of its beneficial effect on dewateriag, as shown ia Figure 5. The beneficial effects of surfactants on dewateriag are most pronounced ia cakes that have been partially deslimed or ia cakes of partially hydrophobic particles (eg, flotation concentrates) that are adsorbed onto each other. Surfactants at or above CMC have Httle practical effect on extremely fine cakes, where pores are small and the cake has no further opportunity to consoHdate. A number of filter cakes do not respond to surfactant addition at any level. 

The beneficiation of this ore type usually involves a combination of gravity concentration, cyanidation and flotation. For an ore with coarse gold, gold is often recovered by gravity and flotation, followed by cyanidation of the reground flotation concentrate. In... 

Figure 7.16. Delkor horizontal belt filter dewatering copper flotation concentrate (filter area 21 m2)...

Tests have been done further on the separation of a Cu-Pb mixed concentration of ethyl xanthate flotation of copper-lead-iron sulphide ore by E- control modifying with H2O2. Test results are presented in Table 10.3. It indicates the possibility of selective flotation separations of copper-lead flotation concentration by control. The feed of copper-lead mixed concentrated assayed Cu 6.53% and Pb 62.38%. Using hydrogen peroxide as a potential modifier, a copper concentration with 24.19% Cu and recovery with 89% can be obtained after separation. 

Figure 10.12 Pulp potential as a function of pH in Xitieshan flotation concentrator...

Applications of OPCF Technology in Several Flotation Concentrators... 

The disintegration degree of a phosphorite flotation concentrate in the functions of temperature and impurity contents in phosphorous acid has been described by a second-order regression model ... 

The conventional method of ore concentration after mining involves (a) crushing and grinding to size, which is determined by the degree of liberation of the minerals from the bulk of the ore and (b) beneficiation of the ore, either by physical means or by flotation technique, whenever applicable to produce a concentrate acceptable to the smelter. In a typical copper operation, the mill feed averages 0.70% copper and the flotation concentrate is anywhere from 25 to 30% copper. 

Lundquist (L17) proposed a leaching scheme in which silica and some silicate minerals are removed by sodium hydroxide solution from very-low-grade manganese ores and manganese flotation concentrates, leaving a product with an upgraded manganese content. Separation of the residue by filtration was carried out at 60-70°C. The spent leach liquor was... 

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