What is the gold crushing process flow? how to extract gold from its ore? In the paper, I make details from the gold crushing circuit, crushing equipment, primary crusher, secondary crusher and tertiary crusher, screening. Join us.
Every gram of gold from the stones is indispensable to experience mining – crushing – grinding – sorting – smelting – casting, etc., from the perspective of mineral processing, the crushing is the first mineral beneficiation process step, and it is almost a preparatory section for any gold processing plant. By crushing process, reduce the large ore to ideal particle size for grinding.
The gold crushing process design is determined by the ore amount, hardness and the crushing ratio.
The most commonly used rock crushers are jaw crushers and cone crushers; in addition, vibrating screens (round vibrating screens) are required to complete the closed circuit with the crushers.
From the structure, the drive system and control system, the jaw crusher and the cone crusher are subdivided into different types. We are here to help model selection.
Jaw crusher is generally used as the primary crusher in the crushing circuit and connects to the ore feeding machine.
In the early years, common used plate feeder, but now, the vibrating feeder is more popular. Practice has proved that the vibrating feeder has advantages of low power consumption, strong transportation capacity, low failure rate and easy maintenance, which can fully meet the needs of both of large scale gold plant ore small scale processing plant.
How to choose a jaw crusher? There are two factors need to take into consideration, that is maximum feed size and ore hardness.
For medium hardness ore, the ore can be gradually crushed from the crusher mouth. For the ore with higher hardness, the material may be broken in the middle of the jaw plate, so that the opening width of the crusher mouth needs to be wider.
Each crusher has a maximum feed size, which surely is not a fixed value. For medium hardness ore, adopt extrusion type feeding mode, even if there is a small amount of large ore exceeding the maximum feed size, has no effect on the work of the crusher. On the contrary, if the material is high hardness ore, it is better to intermittently feed to avoid clogging.
Once the jaw crusher is stuck, turn off the feeder and crusher first, and increase the discharge clearance.
In addition to the maximum feed size, an important parameter of the crusher is the discharge gap. The discharge gap is not equal to the maximum discharge size. The maximum discharge size of the jaw crusher is usually 1.5-1.8 times of the discharge gap.
Each crusher has a minimum discharge clearance. In order to ensure the stability of the crushing process, 1.5-2 times the minimum clearance is selected to complete the first stage of the fracture.
Medium crushing & fine crushing
After coarse crushing, the ore is directly or screened into a secondary crusher or tertiary crusher. Secondary crusher uses standard cone crusher, tertiary fine crusher use short-head cone crusher.
The iron is fatal to the cone crusher, so the ore must be removed before enters the cone breaks. An iron remover (in fact, a magnet) can be added to the upper part of the belt conveyor to preclude the wire, nails, welding heads and the like.
For the cone crusher, it is must use the extrusion feeding method, intermittent feeding method damages the equipment very much.
Therefore, professional cone crusher manufacturers will configure a small buffer tank for the cone crusher. The material from the fine crushing bin can be fed into the buffer tank through a belt feeder or a small vibrating feeder. If use a chute, you can remove the buffer and let the material accumulate directly in the chute.
Similarly, the cone crusher also has the maximum feed size. This parameter value is a mandatory parameter. Never try to exceed it. Once it is stuck due to excessive material, it is very troublesome for the cone crusher.
It should be noted that, due to the closed-circuit crushing formed by the vibrating screen, the cone crusher is not the larger the discharge gap, larger the processing capacity. Different discharge gap determine the different qualified product rates and the ore recrushing rates.
As the gap increases, the actual processing capacity of the crusher increases, the gap becomes smaller, and the speed of the crushing decreases. Both of these two conditions are harmful in production. We should find the best gap in the commissioning to make the production smoother.
As the vertebral body wears, the gap will increase accordingly. In addition, the maximum discharge size of the cone crusher will reach 2-3 times of the discharge gap, so the gap size can be judged according to the granularity of the discharge during the adjustment.
Never blindly adjust without a clue.
Vibrating screens are the important equipment in the crushing process, to check whether the crushing ore is size qualified.
Generally speaking, small scale gold plant use single-layer screen, medium and large mines use double-layer screen, but the purpose of double-layer screens is not to grade three products, but to improve screening efficiency.
Most will choose a long strip of mesh, the length is about 1.5-1.8 times the width.
As for the choice of materials for the screen, it depends on the user’s usage habits. It is certain that the polyurethane (rubber) screen has a longer service life, a lower screening efficiency, and a steel-wire mesh that is more fragile, but has a higher screening efficiency and is easier to maintain.
Screening equipment work at long-term high-speed operation, and its product quality is the key guarantee for the stable operation of the entire mineral processing line.
Due to the relatively harsh environment of the crushing operation, the single shift time is less than 6 hours. Therefore, when selecting the gold crushing machine, the working time is generally determined by two shifts of 6 hours or three shifts of 5 hours.