Improved Flotation of High-Clay-Content Gold Ore Using Fenugreek Polysaccharide Gum as the Depressant
, Kaile Zhao 1, Zhiyong Gao 3,*, Wenpu Zhang 1, Mengyao Zhou 2 and Qiang Deng 4
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsInnovation: The introduction of FGM (flocculation-grade modifier), commonly used in the food/pharmaceutical fields, as a depressant in mineral flotation is a novel approach. Compared to traditional polysaccharide depressants (e.g., guar gum), this topic provides a new strategy for processing high-clay gold ores.
Application Value: Industrial trials demonstrated that FGM significantly improves concentrate grade (+4.7 g/t) with a slight increase in recovery (+0.37%), generating an additional profit of $1.715 million over two years. The economic benefits are substantial, offering valuable insights for similar mining operations.
Methodology and Experimental Design
The experimental design is generally reasonable but requires the following additions:
The flotation flowchart in Figure 1 is disorganized. Optimize chart layout and explicitly highlight differences between old and new systems (e.g., FGM addition points, dosage adjustments of reagents).
Clarify whether the control conditions for old and new reagent systems were strictly identical (e.g., were other reagents unchanged when replacing FGM?) to ensure result reliability.
Include trial repetition counts and error analysis (e.g., standard deviations for concentrate grade and recovery) to enhance data credibility.
Results and Discussion
Data presentation: Table 1 provides clear industrial trial comparisons but lacks performance metrics (e.g., cost, inhibition efficiency) between FGM and other depressants (e.g., guar gum, lignosulfonates) to highlight its advantages.
Mechanistic limitations: While the paper hypothesizes that FGM inhibits pyrophyllite/mica by dispersing their interactions with pyrite surfaces, direct evidence (e.g., zeta potential, FTIR, or adsorption tests) is missing. Supplement with characterization data to clarify the mechanism.
Recovery analysis: Although the 0.37% recovery increase appears marginal, discuss its practical significance at industrial scales (e.g., total annual revenue impact based on throughput).
Conclusions
Address potential limitations of FGM application:
Applicability to ores with higher clay content or differing mineralogy.
Long-term stability (e.g., degradability) and environmental risks of FGM.
Revision Recommendations
Improve chart clarity and supplement reproducibility/error analyses.
Strengthen mechanistic discussions with characterization data.
Compare FGM’s cost and performance against competing depressants.
Define scope and limitations in conclusions.
Polish language and standardize formatting.
Recommendation
This study addresses a practical industrial challenge with well-supported data. While revisions are required to address the above issues, the manuscript is recommended for acceptance pending necessary amendments.
Comments for author File: 
Comments.pdf
Language issues: Correct grammatical errors (e.g., in the abstract, specify the timeframe and methodology for the "$1.715M profit").
References: Ensure consistent formatting (e.g., complete years for Zhao et al., 2019a,b) per journal guidelines.
Terminology: Replace informal terms like "2# oil" with standardized names (e.g., "pine oil").
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThis is an interesting study with an objective approach and a basic but economically attractive result. I recommend that the article may be published, after considering the following question:
The use of the depressant is compared only with the condition without depressant. Was there any prior evaluation or comparison with the use of other types of conventional depressants? Is there any specific justification for choosing “fenugreek polysaccharide gum” over any other? How mutch it is cheaper than carboxymethyl cellulose, guar gum, and lignosulphonate, for example. Is possible explore its on the text?
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThe authors prepared the technical note on potential of using FGM as depressant for flotation of high
clay-content sulfide ores. There are some comments to enhance the quality of paper:
1- It would be beneficial to add a summary of the mechanism by which FGM works as a depressant.
2- As the industrial application is discussed in the paper, it is recommended to add a short economic analysis of using FGM. For example the price of FGM (comparing to other depressants) and final cost of the product considering using FGM.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
