How to Conduct a JinChan Laboratory Test on Gold-Bearing Ore

Source Data

Before starting the laboratory program, it is advisable to obtain:

• material type: ore, concentrate, or tailings;
• gold grade;
• available data on copper, arsenic, and sulfur;
• a description of the current process flowsheet;
• results of previous testwork, if available;
• the anticipated throughput or processing volume.

After the source data have been reviewed, the test program and the required quantity of representative sample are defined.

Preparing a Representative Sample

A laboratory result is meaningful only when the sample adequately characterizes the material being investigated.

The sample is crushed, homogenized, and split so that the test portion does not represent a randomly enriched or depleted fraction of the original ore.

Grinding

Particle size is one of the key factors. Inadequate liberation of gold may limit contact between the leaching solution and gold-bearing minerals.

The degree of grinding is therefore recorded in the test program, and several alternatives are compared when necessary.

Developing the Test Program

A single test cannot define suitable operating conditions. A series of comparable tests should be conducted while varying individual process parameters.

• JinChan dosage
• pH
• Duration
• Slurry density
• Particle size
• Temperature — if it is included in the program

There is no universal set of conditions that applies to every ore: the parameters must be verified on the specific material.

pH Control

The acid–base condition of the slurry is monitored during the test. JinChan is used under alkaline conditions. According to the official Guangxi Senhe instructions, alkalinity is normally adjusted with lime or caustic soda and maintained at pH 11–12.

If the pH decreases, alkalinity is corrected. The manufacturer also notes that maintaining pH above 12 for an extended period may adversely affect the process and subsequent adsorption on activated carbon.

The specific conditions must be documented in the test program and verified on the ore being investigated.

Monitoring Leaching Kinetics

Final recovery is not the only indicator. It is important to understand how quickly the process proceeds.

During a kinetic test, the solution may be analyzed at several time intervals. This helps determine whether recovery is continuing and whether extending the leaching time is justified.

Solution and Tailings Analysis

After the test is completed, both the gold concentration in the solution and the residual gold grade in the solid product are evaluated.

Tailings analysis helps verify the material balance and determine whether unrecovered gold remains in the material under investigation.

A high gold grade in the tailings is a reason to investigate the cause, not to automatically increase reagent consumption.

Comparing Operating Conditions

Operating conditions should be compared across several parameters at the same time:

• gold recovery;
• reagent consumption;
• process duration;
• grinding requirements;
• behavior of associated components;
• subsequent adsorption;
• potential applicability at the plant.

The highest laboratory recovery does not always represent the most economical industrial operating conditions.

What the Laboratory Program Delivers

• Recommended dosage
• Operating pH range
• Required particle size
• Leaching duration
• Indicative recovery under the test conditions
• Recommendations for an industrial trial

These parameters apply to the sample investigated and are not universal JinChan specifications for every ore.

From Laboratory to Plant

A successful laboratory test provides the basis for the next stage; it is not final confirmation of industrial operating conditions.

Before full-scale implementation, the selected parameters must be verified under plant conditions, taking into account the equipment, hydrodynamics, recycled water, adsorption, and actual process stability.