Selection of precious liquid purification equipment and replacement equipment

First, the precious liquid purification equipment

Before the replacement of the cyanide plant precious liquid, it needs to be purified to remove the slime and other suspended solids. Generally, the suspended matter content is below 5mg/L. In addition, in order to ensure the replacement effect, it is also necessary to remove the dissolved oxygen in the noble liquid. Therefore, the purification equipment includes a clarifier and a deoxidizing device.

The clarifier can be a plate and frame vacuum filter and a tube filter. The former has a simple structure and a good purification effect, but the filter cake is inconvenient to clean and labor intensive, and the newly designed cyanide plant is less used. Production practices in some cyanide plants indicate that the plate-and-frame vacuum filter has a unit capacity of 2.7 m ³ /(m ² ·d). The tubular filter is a better purification device at present, and has a simple structure, reliable operation and convenient operation. Its technical performance is shown in Table 1.

Table 1 Tube filter technical performance

Note: LSA is a PE microporous sintered tubular filter. The unit of filtration is m ³ /h per unit.

The deoxidation equipment is generally used in the vacuum deoxidation tower. It is a cylindrical cone bottom tower. The upper part of the tower is equipped with a solution shower, the middle part is a plastic point wave packing layer to prevent the liquid from falling directly, and the packing layer is sieved by the lower part of the tower. Board support. The solution in the deoxidation tower is sucked into the top of the tower by vacuum, and then sprayed onto the packing layer by the sprayer, and the dissolved gas in the liquid is released under the action of vacuum to achieve the purpose of deoxidation. The deoxidizing liquid is sent to the replacement operation by the cone bottom liquid discharge port. The height of the deoxidation tower is generally not less than 3m, and the cross-sectional area is related to the amount of precious liquid, which can be calculated according to the formula A=W/q; Where A is the cross-sectional area of ​​the deoxidation tower, m ³ /d; q. The solution volume per unit cross-sectional area, m ³ /(m ³ ·d); the value is determined by the test, and no test data can be used: q _o =400 ~900m ³ /(m ² ·d).

At present, the specifications of the deoxidizing tower are: ф1.0×3.5; ф1.2×3.6; ф1.5×3.6; ф1.8×4.0. The vacuum equipment associated with the deoxidizing tower is generally the jet pump, and its technical specifications are shown in Table 2.

Table 2 Water jet pump specifications

Second, the replacement equipment selection

In addition to completing the displacement reaction, the replacement device simultaneously separates the solid and liquid to obtain a filter cake and a lean liquid. Replacing the same zinc powder substitution host, there are three: plate and frame filter press, and the replacement filter bag filter press. Since the amount, grade and gold content of the gold mud of each plant fluctuate greatly, and the time for extracting the gold mud can be customized, the replacement equipment can be selected without reference to the standard zinc powder replacement device (see Table 3).

Table 3 Strive for the standard zinc powder replacement device