Application of Jaw Crushers and Hammer Crushers in Gold CIL Plant

Application of Jaw Crushers and Hammer Crushers in Gold CIL Plant

In a gold CIL (Carbon-in-Leach) plant, the crushing circuit is the first critical stage of size reduction. The PE Jaw Crusher and PC Hammer Crusher are commonly used in combination, with the jaw crusher serving as the primary crushing unit and the hammer crusher handling secondary or fine crushing duties.

PE Jaw Crusher: Primary Crushing

The PE series jaw crusher is typically the first piece of crushing equipment in the circuit. It is designed to handle the large, hard rock directly from the mine.

Role and Function: Its primary function is to reduce Run-of-Mine (ROM) ore, which can be as large as 500–1500mm, down to a size suitable for secondary crushing or grinding . It uses compressive force to break the material .

Key Advantages: PE jaw crushers are known for their high reduction ratio (approximately 6:1) and robust construction, making them ideal for hard, abrasive gold-bearing quartz ores . They feature a reinforced toggle plate for shock absorption and are often equipped with a deep crushing chamber to increase capacity .

Typical Specifications: In a medium-sized gold plant (e.g., 200 TPD), a model like the PE400×600 is often used, with a motor power of 30kW, to crush raw ore down to ≤150mm . Larger operations may use models such as the PE600×900 or PE750×1060 .

PC Hammer Crusher: Secondary and Fine Crushing

The PC hammer crusher is often used after the jaw crusher for secondary or fine crushing, particularly in smaller to medium-sized CIL operations.

Role and Function: It uses high-speed rotating hammers to impact and shear materials, breaking them into smaller pieces . It can accept feed material with a maximum size of up to 600–1800mm and reduce it to less than 25mm . This fine crushing step is crucial for preparing the ore for the grinding mill (such as a ball mill), which will further reduce the particle size to allow gold liberation for cyanidation .

Key Advantages: Hammer crushers offer a high crushing ratio and a relatively simple structure, which translates to lower operating costs . They are suitable for crushing medium-hard and brittle materials with a compressive strength not exceeding 100MPa, which covers many types of gold ores . The discharge size can be adjusted by changing the gap between the hammers and the screen plate .

Typical Specifications: A PC400×300 model is suitable for a small plant, with a capacity of 5-10 t/h and an 11kW motor . Larger models like the PC800×800 can handle 25-50 t/h with a 45kW motor .

Combined Application in the CIL Flowsheet

In a typical gold CIL plant flowsheet, the two crushers work in sequence. The ROM ore is first fed into the PE Jaw Crusher to be broken down from large boulders. The crushed product is then conveyed to the PC Hammer Crusher for further size reduction. The final finely crushed product is then sent to the grinding circuit (e.g., a ball mill) to be ground into a fine slurry, which then proceeds to the CIL tanks for cyanide leaching and gold adsorption . This two-stage crushing setup efficiently prepares the ore for downstream processing, ensuring proper particle size for effective gold extraction.