Study on Beneficiation Process for Recovery of Black and White Tungsten from Original Secondary Mud

Fine mud crushing system and crushing wash raw mineral beneficiation plant is native fine mud, fine grinding mill system for secondary raw mineral mud fine mud. A tungsten mine in Jiangxi uses tungsten to re-selection method; daily processing capacity is 2200-2500t, daily raw fine mud is 150-400t, WO ₃ grade is 0.13%-0.3%, secondary fine mud is 300-400t, and WO ₃ grade is 0.15%- 0.3%, mixed fine mud daily production of 500-800t, WO ₃ grade 0.13%-0.3%. Via multi-program comparison, gravity separation Preconcentration - Flotation - sorting process combined reselection mine mixing fine mud, small closed-circuit test obtained 55.30% of WO ₃ grade scheelite flotation concentrate grade of 38.76% and WO ₃ the wolframite concentrate recoveries were 38.25%, 41.76%, WO ₃ grade tungsten concentrates total 45.26%, 62.33% recovery. After the ACID leaching of the white tungsten flotation concentrate, a final scheelite concentrate containing 70% of WO ₃ can be obtained.

First, the nature of the ore

Slimes mixed (Primary and Secondary Slimes mixed 1 to 1 ratio) useful minerals wolframite, scheelite, followed by a molybdenite, bismuthinite, natural bismuth, tungsten China, pyrite, pyrrhotite, yellow copper ore and a small amount of malachite, zircon, gangue minerals as quartz, mica, calcite, tourmaline, garnet and rutile, etc. beryl. The mixed fine mud contains W0 ₃ 0. 21%, of which the scheelite content is 0.094%, the total tungsten occupation rate is 45.30%, the wolframite content is 0.11%, and the total tungsten occupation rate is 53.01%. The multi-element chemical analysis of mixed fine mud and the results of sieve water analysis are shown in Tables 1 and 2, respectively.

Table 1 Multi-element chemical analysis results of mixed fine mud %

Table 2 Mixing fine mud sieve water analysis results

It can be seen from Table 2 that the fine fine fraction in the mixed fine mud is very high, the yield of -0.02 mm is 31.95%, and the tungsten occupation rate is 25.92%.

Second, the beneficiation process test

From the nature of the ore, it is known that the tungsten in the mixed fine mud is mainly black tungsten ore and scheelite. The ratio of the two is about 5:6. It is identified under the microscope. The wolframite is unevenly distributed, and the coarse particles are above 0.074 mm. Only 0.04-0. 0l mm, scheelite is generally finer than wolframite. According to the characteristics of black and white tungsten ore in the mixed fine mud, the flotation process is carried out by flotation-re-election process, re-election pre-enrichment-flotation-re-election process, re-election pre-enrichment-flotation-magnetic separation-heavy A comparison test of the three processes of the selection process.

(1) Flotation-re-election dressing process test

With butyl xanthate flotation oil ^# 2 and sulfide ore tailings by NF adjusted desulfurization agent gangue minerals inhibitor, an inhibitor of modified sodium silicate, lead nitrate tungsten activator, TA-4 as tungsten Collecting agent , black and white tungsten mixed flotation, mixed flotation concentrate, improved flounder flotation by modified "Peterlow method" to obtain white tungsten flotation concentrate, heated floatation tailings with shaker to recover black Tungsten. The flotation-reselection method for small closed circuit test is shown in Figure 1, and the test results are listed in Table 3.

Table 3 Flotation-re-election process small closed-circuit test results %

Figure 1 Mixed fine mud flotation - re-election process small closed circuit test process

The white tungsten flotation concentrate can be obtained by acid leaching to obtain WO ₃ 59.55 % of the final scheelite concentrate.

(II) Re-election pre-enrichment-flotation-re-election dressing process test

The mixed fine mud is first pre-concentrated by re-election using a centrifuge-shaker, the centrifuge is used for one rough selection and one selection, the shaker is used for sweeping, and the centrifuge selects the concentrate and the shaker concentrate into a heavy weight. Pre-concentrated concentrate, re-selected pre-enriched concentrate, concentrated with Dinghuang, 2 ^# oil flotation sulfide, sulfide ore flotation tailings with NF as modifier, modified water glass as inhibitor, nitric acid Lead activator, FB and TA3 as collectors for black and white tungsten mixed flotation, black and white tungsten mixed flotation concentrate with modified "Peterlow method" after heating and flotation to obtain white tungsten flotation concentrate, The warm flotation tailings are recovered by a shaker to recover the wolframite. The re-selection pre-enrichment-flotation-re-election method is shown in Figure 2, and the test results are listed in Table 4.

Figure 2 Mixing fine mud re-preconcentration-flotation-re-election process small closed-circuit test procedure

Table 4 Mixed fine mud re-preconcentration-flotation-re-election process small closed-circuit test results %

After the acid leaching of the white tungsten flotation concentrate, W0370. 00% of the final scheelite concentrate can be obtained.

(III) Re-election pre-enrichment-flotation-magnetic separation-re-election dressing process test

The mixed fine mud is first pre-concentrated by re-election using a centrifuge-shaker, the centrifuge is used for one rough selection and one selection, the shaker is used for sweeping, and the centrifuge selects the concentrate and the shaker concentrate into a heavy weight. Pre-concentrated concentrate, re-selected pre-enriched concentrate, concentrated with Dinghuang, 2 ^# oil flotation sulfide, sulfide ore flotation tailings with NF as modifier, modified water glass as inhibitor, nitric acid Lead activator, FB and TA3 as collectors for black and white tungsten mixed flotation, black and white tungsten mixed flotation concentrate with modified "Peterlow method" after heating and flotation to obtain white tungsten flotation concentrate, The heated flotation tailings is strongly magnetically selected by a high gradient magnetic separator, and the magnetic products are washed with black tungsten concentrate. The re-selection pre-enrichment-flotation-magnetic separation-reselection process is shown in Figure 3, and the test results are listed in Table 5.

Figure 3 Mixed fine mud re-preconcentration - flotation - magnetic separation

-Reselection process small closed circuit test process

Table 5 Mixed fine mud re-preconcentration - flotation - magnetic separation - re-election process small closed-circuit test results %

After the acid leaching of the white tungsten flotation concentrate, W0370.00% of the final scheelite concentrate can be obtained.

Third, analysis

(1) Analysis of beneficiation efficiency

Three kinds of beneficiation process tests of black and white tungsten mixed fine mud. See Table 6 for the beneficiation efficiency of total tungsten concentrate.

From the perspective of the beneficiation efficiency of the total tungsten concentrate, the flotation-re-election process is similar to the re-election pre-enrichment-flotation-re-election process.

Table 6 Three ore dressing process tests of black and white tungsten mixed fine mud test for the ore dressing efficiency of total tungsten concentrate

Note: The beneficiation efficiency is calculated by the Fleming-Stevens formula, the same below.

(II) Analysis of recovery effect of scheelite and wolframite in mixed fine mud

The recovery effects of the scheelite and wolframite in the three types of beneficiation processes for the recovery of mixed fines are shown in Table 7.

Table 7 Recovery effect of scheelite and wolframite in mixed fine mud

It can be seen from Table 7 that the recovery of scheelite from the flotation-re-election process is better than the other two processes, while the recovery of the wolframite is worse than the other two processes. The white tungsten flotation concentrate obtained by the flotation-re-election process is acid leached to obtain WO ₃ 56.55% scheelite concentrate, and the other two processes obtain the white tungsten flotation concentrate after acid leaching. WO ₃ 70.00% scheelite concentrate.

(III) Analysis of the loss of tungsten in tailings

Preconcentration using reselection process, tailings reselection preconcentration WO ₃ loss rate of 22.04%, Wolfram flotation tailings WO ₃ loss rate of 2.01%. Without the re-selection pre-enrichment flotation-re-election process, the loss rate of WO ₃ in black and white tungsten mixed flotation tailings is 19.83%, which indicates that there is a considerable part of the fine-grained tungsten float in the mixed fine mud. It is also difficult to recover effectively, and it can be discarded by re-concentration pre-enrichment, so that the tungsten in the mixed fine mud can be pre-enriched.

(4) Analysis of mineral processing

The re-election pre-enrichment process can pre-discard 88.23% of the mixed fine mud, which not only greatly reduces the amount of minerals entering the subsequent operations, but also acts as a de-sludge and pre-enrichment for the fine mud, so that the grade of the mixed fine mud is included. WO ₃ 0.21% was increased to 1.5%-2%, the yield of black and white tungsten mixed flotation concentrate was 13.26%, and the yield of mixed fine mud was 1.56%. The flotation-re-election process is not de-sludged, affected by a large amount of slime, the flotation foam volume is large, the flotation process is unstable, the yield of black and white tungsten mixed flotation concentrate is 7.219%, and the mixed fine mud WO ₃ grade is 3.30%. This increases the difficulty of heating and subsequent flotation and re-election operations and the difficulty of black and white tungsten sorting, and increases the ore dressing cost of these operations.

(5) Analysis of pharmaceutical expenses

The agent costs for the three types of beneficiation process tests are shown in Table 8.

Table 8 Pharmacy cost results of three kinds of beneficiation process tests

It can be seen from Table 8 that the cost of processing the chemical per ton of mixed fine mud by the re-concentration pre-enrichment process is 3.20 yuan, which is much smaller than the 19.64 yuan using the flotation-re-election process.

In summary, for the ore containing low tungsten, 0.1%-0.4%, -0.043 mm fractional yield of about 78%, -0.02 mm fractional yield of 31.95% of black and white tungsten mixed fine mud, should be re-selected The enrichment-flotation-re-election beneficiation process recovers the wolframite and scheelite.

Fourth, the conclusion

(1) Black and white tungsten mixed fine mud (the original secondary fine clay is mixed in a ratio of 1:1) containing WO ₃ 0.21%, of which white ore content is 0.094%, total tungsten occupation rate is 45.30%, and black tungsten ore content is 0.11%. The tungsten occupation rate is 53.01%.

(2) The black and white tungsten mixed fine mud has a high fine particle content, the -0.043mm tungsten occupation rate is 89.07%, and the -0.22 mm tungsten occupation rate is 25.92%.

(III) Experimental studies on three beneficiation processes indicate that the re-election pre-enrichment-flotation-re-election process should be used to recover the black tungsten ore and scheelite in the original secondary sludge, the selection index, and the white tungsten flotation Concentrate recovery rate was 29.82%, WO ₃ grade was 55.38%, black tungsten concentrate recovery rate was 32.00%, WO ₃ grade was 37.00%-39.00%, total tungsten concentrate grade was 45.26%, and recovery rate was 62.33%. After soaking the white tungsten flotation concentrate, a white tungsten concentrate containing WO ₃ 70.00% can be obtained.