A Complete Mobile Treatment Chain to Produce Drinking Water from Sources Heavily Contaminated by Inorganic and Organic Compounds

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript entitled “A Complete Treatment Chain to Produce Drinking Water from Sources Heavily Contaminated by Inorganic and Organic Compounds” presents a comprehensive and well-structured study. The experimental design and discussion are complete and technically sound. After careful review and revision, I recommend this manuscript for publication in Water, pending minor revisions as outlined below:

1. Introduction:
The authors are encouraged to expand the Introduction section by including a brief comparison of different existing technologies or methods for producing drinking water from contaminated sources, highlighting their respective advantages and limitations.

2. Figure 1 – Process Description:
The explanation accompanying Figure 1 should be enhanced by clarifying the individual roles and removal mechanisms of the different filter media with respect to turbidity, total dissolved solids (TDS), hardness, and iron.

3. System Evaluation and Cost Analysis:
It is recommended to include a cost estimation or comparative cost analysis for the proposed system, in order to evaluate its economic feasibility relative to other conventional water purification methods.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript entitled “A complete treatment chain to produce drinking water from two sources heavily contaminated by inorganic and organic compounds” presents the development and testingof an integrated system designed to produce drinking water from raw water sources impacted by multiple contaminants. The topic is relevant and of potential practical significance. However, the manuscript requires substantial improvement in writing, organization, and presentation before it can be considered for publication. Specific comments are provided below.

 

Abstract

The abstract should be rewritten to follow a more logical and reader-friendly sequence, including (i) context and background of the problem, (i) objective of the study, (iii) methodology, with explicit mention of the system development process, (iv) main results, and (v) principal conclusion or implication.

 

1. Introduction

The introduction is generally acceptable in content and structure.

 

2. Materials and Methods

- The acronym “ICP” should be defined at its first appearance.

- For a study that claims to have developed and successfully tested a water treatment system, the system development should be described before the preparation of the water to be treated. The current structure gives the opposite impression. Please consider revising the manuscript for a more fluid structure.

- The title of section “2.1 Test bench sand filtration unit” does not differ meaningfully from the following section’s title (“2.2”) and does not accurately reflect its content.

- Section “2.1” should be divided into two subsections to improve clarity: “2.1.1 Characteristics of sand filters”, and “2.1.2 Filtration tests of sand filters”

- In Table 2, please provide the meaning of all abbreviations used.

- It is strongly recommended that the bench-scale tests conducted to identify the best-performing components for the pilot system be included in the supplementary material, since they are ancillary to the main study objective.

 

“2.5 Description of the Pilot-Scale Drinking Water Production Unit”

- A schematic diagram and an actual photograph of the treatment system should be included in the main text to aid understanding.

- The system configuration and assembly procedures should be described in sufficient detail to allow replication.

- The preparation of the test water should be detailed in a separate section, ensuring clarity regarding sources, proportions, and preparation procedures.

- The statement “After modifying the water treatment system, it was installed in a mobile trailer” requires clarification: Which version was modified, and what specific modifications were made?

- The statement “The water used for these tests came from the Environmental Hydraulics Laboratory 226 (LEE) at INRS, (…)” appears inconsistent with the earlier information that the water consisted of 20% wastewater and 80% river water. Please clarify.

- The phrase “The next step is a 25.4 × 111.8 cm anionic resin tank with a head controller” next step?

- Overall, section 2.5 requires substantial revision for clarity and conciseness. The subtitle does not reflect the section’s content adequately. The information is presented in a disorganized and repetitive manner; secondary details are sometimes emphasized, while essential information is missing. The text should be reorganized to follow a logical progression: system description, operational conditions, test water, and analytical methods.

- Avoid unnecessary details about commercially preassembled components, but provide enough technical information for the reader to understand their function within the system.

- Before describing Analytical methods, explain how the water was treated (treatment duration, flow rate, sampling procedures, storage, and transportation).

- Figure 2 would be more appropriately placed within the Methodology section. The font size in the figure should be significantly increased to enhance readability.

- Up to the end of the Materials and Methods section, it remains unclear whether the system was designed to treat water contaminated with all contaminants simultaneously or separately. Please clarify this aspect explicitly.

 

General Comment: The Materials and Methods section requires major revisions to enhance clarity, precision, and objectivity, ensuring that the description of procedures and results aligns closely with the stated objectives of the study.

 

3. Results and Discussion

- Given that this is an innovation-focused study, the technical procedures describing the system’s development should be presented clearly and sequentially, following a logical and intuitive order, and with an appropriate balance of detail. Nonessential or secondary information should be avoided.

- Similarly, the Results should ideally be presented separately from the Discussion, to ensure objectivity and clarity. Please consider restructuring these sections accordingly.

- As suggested for the Methodology section, the preliminary test results of individual components (subparts) used in building the system should be transferred to the supplementary material, since these experiments were performed prior to the current work and served only to guide the selection of components. Including extensive detail on these parts in the main text may give the impression of commercial promotion, particularly if the components were purchased from specific suppliers. Therefore, please focus the main text exclusively on the results obtained from the developed and tested system.

- The sections “3.1 Evaluation of the performance of different filter media” and “3.2 Evaluation of the performance of different membranes” should also be moved to the supplementary material.

- In “3.3 Evaluation of the performance of the initial water treatment process,” please clarify whether the expression “initial water treatment process” refers to the performance of the initial system configuration. If so, adjust the subsection title accordingly for greater precision.

- Note that most of section 3.3 reads as Materials and Methods, except for Table 8. Ensure that only results are included in the Results section, and reserve interpretation for the Discussion.

- Toward the end of the manuscript, information regarding the microbiological quality of the treated water is insufficient; it is unclear whether this is due to missing methodological details or absent results. Please clarify and ensure this information is fully presented.

- Finally, the manuscript would benefit from a dedicated Limitations section and a brief Recommendations for Future Studies section, which are essential in applied and innovative research to contextualize findings and guide subsequent investigations.

Comments on the Quality of English Language

The manuscript would benefit from thorough English language revision to enhance clarity and fluency.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript addressed the development and evaluation of a complete treatment chain to produce potable water from sources contaminated by inorganic, organic, and energetic compounds. It demonstrated a comprehensive experimental design combining sediment filtration, Greensand, ion exchange, activated carbon adsorption, ultrafiltration, UV disinfection, and reverse osmosis, effectively meeting water quality standards under simulated field conditions. However, its limitations included a lack of long-term performance evaluation, insufficient discussion on energy consumption, membrane fouling mitigation, and cost-effectiveness under variable field conditions. The work contributed valuable insights but required deeper comparative analysis with existing technologies and more robust statistical treatment of results. Therefore, I suggest the manuscript has to be reviewed after a Major Revision. The specific comments are as follows:

 

Major Concerns:

• Lines 89–90. The study described the preparation of highly contaminated water but did not provide justification for choosing concentration levels 5–50 times higher than standard criteria, which limited the environmental relevance of the test conditions.
• Lines 70–93. The contamination procedure used ICP standard solutions and stock mixtures, but the reproducibility and homogeneity of spiking were not statistically validated, reducing experimental reliability.
• Section 2.3. The discussion of reverse osmosis limitations remained general and lacked quantitative evaluation of membrane fouling rates or recovery efficiencies.
• Lines 152–176. The membrane filtration protocol listed operational steps in detail but omitted replicate trials and uncertainty ranges, preventing assessment of data consistency and repeatability.
• Lines 189–196. The operation parameters for each filtration system were reported without error margins or variance, leaving uncertainty about performance variability under dynamic flow conditions.
• Lines 206–225. The pilot unit description emphasized equipment details but did not evaluate the scalability of the system or its resilience to fluctuating field conditions, which limited practical applicability.
• Lines 295–316. The filtration media evaluation focused on removal percentages but did not address long-term media exhaustion or regeneration efficiency, making sustainability of performance unclear.
• Lines 360–385. The membrane comparison table summarized removal rates but omitted discussion of energy consumption and transmembrane pressure trends, leaving gaps in process optimization analysis.
• Lines 420–450. The integrated treatment chain design was technically sound, yet the manuscript did not analyze the sequence optimization or potential redundancy among filtration steps.
• Lines 452–458. The final performance test used 400 L contaminated water but lacked microbial data and did not assess biological safety, which was essential for a potable water system validation.
• The title claimed that heavily contaminated sources were directly processed to produce drinking water, which might have overstated the applicability and safety of the system. Given the extreme contamination levels, an ethical clearance or biosafety assessment should have been documented to ensure no health risk occurred during testing or handling.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors improved the manuscript based on my comments.

Reviewer 3 Report

Comments and Suggestions for Authors

The paper has been appropriately revised and the current version can be accepted.