Towards a Cleaner Textile Industry: Using ASEC to Decrease the Water Footprint to Zero Liquid Discharge

Round 1

Reviewer 1 Report

In this study the authors investigated efficiency of ASEC technology for the textile industry waste.  Although the study done is very interesting and well written, the coverage is not sufficiently balanced, comprehensive and critical, and the scientific conclusions should be justified by the literature presented - a more detailed discussion of the obtained results is necessary. In addition to this general comment, the authors should take into account the following corrections to improve their paper:

1. The title does not adequately describe the point of the study. Correct it

2. The Abstract is too long. It should highlight the purpose of the study, describe briefly the main methods applied, summarize the main experimental findings and results, and indicate the main conclusion. Rewrite this section.

3. In Introduction part highlight the novelty and scientific contribution of this study

4. Indicate the exact origin of the investigated samples

5. Provide a more detailed description about ASEC technology

6. It is also suggested to tabulate and compare results obtained in this study with previously published data

7. since the paper presents a large number of results, it would be advisable to use some statistical method for their processing (for example ANOVA RSM...)

8. Conclusion is too long and informative. It should report more results and not only observations. I suggest rewriting this part avoiding descriptive sentences and reporting more data

Author Response

#Reviewer 1

1. The title does not adequately describe the point of the study. Correct it.

Following the reviewer's suggestion, the title has been changed.

2. The Abstract is too long. It should highlight the purpose of the study, describe briefly the main methods applied, summarize the main experimental findings and results, and indicate the main conclusion. Rewrite this section.

Following the reviewer's suggestion, the abstract was shortened following the different parts.

3. In Introduction part highlight the novelty and scientific contribution of this study

Following the reviewer's suggestion new information was added […] An innovative and disruptive technology based on adiabatic and sonic acceleration was designed for a total recovery of water from liquid residues, obtaining freshwater and crystallized solids as useful byproducts. This is named Adiabatic Sonic Evaporation and Crystallization (ASEC), which can completely separate water from particulate and dissolved solids. Recently, [18] already tested the technology with mining residues with 100% of efficiency (100% water recovery as distilled water) and obtaining valuable crystallized solids for raw material recovery.[…] This is the first time, that the depuration technology is used with textile wastes, and characterization of the byproducts are here presented.

4. Indicate the exact origin of the investigated samples

Samples were provided by the industries. The information required is included in the manuscript[…] The scheme of the industrial processes for both, synthetic fibers (Sf) and natural fibers (Nf), comprises a series of phases (partially cyclical) summarized according to the schemes in Figure 1. For the Sf, different amounts of water at different temperatures intervene through baths with glues, detergents, dyes, fixatives, etc. These compounds will be in solution in the output effluents, with a total of averaged volume of 150 m³ used in the industrial process per day. These volumes liquid waste from the factory´s domestic uses are treated at the wastewater treatment plant (WWTP). Aliquots of three different liquid residue samples were collected from the different phases of the Sf textile processing line (Figure 1). Sample S1 was water from the preparation phases of the autoclaves. The second sample (S2) was collected from the staining and dyeing phases called jiggers mixture with fluid from the previous treatment (Figure 1). Finally, sample S3 was the effluent from the two previous phases of fabric treatment plus residual water sewage from the different facilities of the textile company collected before the WWTP.  In the case of the Nf textile manufacture, some of the processes were different (Figure 1), but also chemicals and treatments (dispersants, surfactants, colorants, etc.). The fourth sample was collected from the Nf textile manufacturer after all the treatments and together with the domestic wastes but before the WWTP (homologous to S3). The daily volume employed by this industry is 950 m³. […]

5. Provide a more detailed description about ASEC technology

A greater detailed about the ASEC technology can be found in the reference 18, which is included in the section 2.2. In any case, new paragraphs have been included through the text describing more precisely the ASEC technology and process.

6. It is also suggested to tabulate and compare results obtained in this study with previously published data

Previous data was included in reference 18. Elemental composition from other residues are different, due to previous samples had different origins (mining, acid water and brines).  A comparative table would be incomplete.

7. since the paper presents a large number of results, it would be advisable to use some statistical method for their processing (for example ANOVA RSM...)

The number of samples is not enough for proper statistical analyses.

8. Conclusion is too long and informative. It should report more results and not only observations. I suggest rewriting this part avoiding descriptive sentences and reporting more data

Following reviewer´s suggestion, the conclusion section was modified and information was added.

Reviewer 2 Report

Manuscript ID: water-2603532

Type of manuscript: Article

Title: Towards a cleaner textile industry: the liquid residue treatment challenge

Comments:

·       The text is not free of grammar, punctuation, spacing, and syntax errors. For example; in line 56 please change the “chromium (VI)” to “chromium(VI)”, line 76 “55 %” change to “55%”, line 72 “to” change to “according to”, line 147 “50 litres” change to “50 liters” or “50 L”, line 179 “7 g per litre” change to “7 g/L”, line 213 “an 8%” change to “to 8%”, line 220 “5187 ton” change to “5187 tons”, line 221 add “, and” before “3833”, line 224 “[24,25,26,27]” change to “[24-27]” etc. These are just some examples of mistakes in the text and there are more in the text. Ensure that your English manuscript is guaranteed free of language issues.

·       Use identical format for units through whole the text.  

·       Ensure predefined all abbreviated words before use and used in the proper place.

·       In the introduction, the authors more than the main contribution of this work (advantages of Adiabatic Sonic Evaporation and Crystallization, ASEC), have discussed the importance of the removal of dyes. Therefore, I recommend the authors highlight the importance of the ASEC by referring to the relevant literature published recently. Also, they can prepare a comparative table of recently published articles in this field and go into deep explanations and related developments in ASEC.

·       Please improve the quality of the Figure 1.

·       Please discuss the details of Figure 1 further in Section 2.1. You can separate Figure 1 into 2 parts (a) and (b) to avoid repetition of “Figure 1” in the text and make it easier for the reader to understand.

·       Please explain about the role and effect of pH, how to choose the optimal pH and its performance in highly acidic and alkaline environments using the ASEC method to remove of contaminants.

·       Please provide a general schematic mechanism for contaminant treatment via the ASEC method.

·       Please write the name of the physicochemical analysis used to prepare Table 1 in the table title.

·       The study of electrical conductivity is mentioned in the abstract and the text. Please discuss more about its importance and application.

·       In this method, is the pollutant completely treated or is it only separated from the water environment? What is the purity percentage of crystallized solid metals remaining after the test operation? Considering that the separation of these metals also requires secondary separation steps for industrial applications, can this method alone be a green method for removing contaminants?

·       What are the bottlenecks of this work and how did you mitigate the impacts attributed to them?

·       How did you do quality control (QC) and quality assurance (QA) on the obtained data to validate the conclusions?

·       Based on the data obtained, what are the implications of this work (a) to the field of study, (b) to industry, (c) economy, and/or (c) to the wider public/society in general?

·       Please develop the adverse effect of textile organic dye pollutants on environmental pollution based on the following works:

·       https://doi.org/10.1016/j.jmmm.2018.02.067

·       https://doi.org/10.1016/j.ultsonch.2018.06.003

 

·       Check the format of all references and write them in the same format.

The text is not free of grammar, punctuation, spacing, and syntax errors. Ensure that your English manuscript is guaranteed free of language issues. 

 

 

Author Response

#Reviewer 2

The text is not free of grammar, punctuation, spacing, and syntax errors. For example; in line 56 please change the “chromium (VI)” to “chromium(VI)”, line 76 “55 %” change to “55%”, line 72 “to” change to “according to”, line 147 “50 litres” change to “50 liters” or “50 L”, line 179 “7 g per litre” change to “7 g/L”, line 213 “an 8%” change to “to 8%”, line 220 “5187 ton” change to “5187 tons”, line 221 add “, and” before “3833”, line 224 “[24,25,26,27]” change to “[24-27]” etc. These are just some examples of mistakes in the text and there are more in the text. Ensure that your

Following reviewer´s suggestion, those and similar issues have been corrected

English manuscript is guaranteed free of language issues. Following reviewer´s suggestion, English was reviewed by experts.

• Use identical format for units through whole the text.  Following reviewer´s suggestion, those and similar issues have been corrected
• Ensure predefined all abbreviated words before use and used in the proper place.

Following reviewer´s suggestion, it was checked.

• In the introduction, the authors more than the main contribution of this work (advantages of Adiabatic Sonic Evaporation and Crystallization, ASEC), have discussed the importance of the removal of dyes. Therefore, I recommend the authors highlight the importance of the ASEC by referring to the relevant literature published recently. Also, they can prepare a comparative table of recently published articles in this field and go into deep explanations and related developments in ASEC.

Following reviewer´s suggestion, removal of dyes literature was introduced. The importance of ASEC was explained in section 3.4 and 3.5. However, we cannot include a comparative table due to the novelty of the treatment system, because wastes, treatment is not comparable with other technologies. Even thought, we have results with seawater brine, and brackish aquifer comparison table that is submitted to other journal. So, we do not wish duplicate information.

• Please improve the quality of the Figure 1.

Following reviewer´s suggestion, quality of the figure 1 was improved

• Please discuss the details of Figure 1 further in Section 2.1. You can separate Figure 1 into 2 parts (a) and (b) to avoid repetition of “Figure 1” in the text and make it easier for the reader to understand.

Following reviewer´s suggestion, figure was separated and was further discussed in section 2.1.

• Please explain about the role and effect of pH, how to choose the optimal pH and its performance in highly acidic and alkaline environments using the ASEC method to remove of contaminants.

The process is designed using the correct material depending on the pH values. Regarding the process that is based on an evaporation and crystallization in one step, the values of pH between 0 and 12 have been successfully demonstrated to work, even pH under 0 values. The approach used when different pH used is based on the resistance of the material to the free proton concentration that is not affecting the material. Because the process does not use chemicals the pH values only should be taken in consideration in this sense, the quality of the material that should be designed to work at different pH values. In our study, the pH values considered are in the interval from 6 to 8 and then the material used was not affected so none special consideration is needed.

 

• Please provide a general schematic mechanism for contaminant treatment via the ASEC method.

Further information can be found in the reference 18 and in the World International Patent Organization: EP3135635. Main mechanisms are explained in section 2.2. and the proper name of the technology, Adiabatic Sonic Evaporation and Crystallization.  […]for contaminated fluid purification using a physical approach without the use of chemicals by distillation for the separation of particulate and dissolved solids and liquids based on adiabatic changes and acceleration of particles[…]. Schematic description of the process is already included in the mentioned patent and the reference.

• Please write the name of the physicochemical analysis used to prepare Table 1 in the table title.

We are not sure that we understood properly the comment of the reviewer regarding ‘name of the physicochemical analysis the description of the apparatus and methods used to obtain the values included in table 1, were described in the material and method section of the paper.

• The study of electrical conductivity is mentioned in the abstract and the text. Please discuss more about its importance and application.

The electrical conductivity (EC) of a liquid (thus, all the fluids treated by ASEC) depends on the number of ions per unit volume and upon their drift velocity. Also, this velocity depends upon different variables such as the mass of the ion and other factors. The ASEC process significantly decrease the values of EC to about distilled water in the output fluid because the efficiency of the processes of which they are based, first evaporation and then crystallization of the fluid. By evaporating all the water in the sample, the solution of ions is almost negligence because the water is obtained after the condensation of the water evaporated being the EC the key parameter to determine the efficiency of the ASEC process.

• In this method, is the pollutant completely treated or is it only separated from the water environment? What is the purity percentage of crystallized solid metals remaining after the test operation? Considering that the separation of these metals also requires secondary separation steps for industrial applications, can this method alone be a green method for removing contaminants?

The ASEC technology allows a complete separation of water and the dissolved elements. Of course, a secondary treatment of the generated solids would require "mining extraction".

• What are the bottlenecks of this work and how did you mitigate the impacts attributed to them?

There are two main bottlenecks in the ASEC process to treat contaminated fluid, including those described in this paper coming from the textile industry: energy consumption and potential fouling of specific material from some of fluid treated. In this sense, the ASEC process can be conducted using renewable source of energy (photovoltaic, thermos solar, wind, etc.) and even residual heat when available in the industries that generate these fluids. The ASEC system mainly needs heat instead of electricity to be properly run. The other bottleneck is related to the correct selection and design of the materials to be used in the ASEC process to avoid any fouling or similar problem that could decrease the efficiency of the process. Regarding the approaches used in this work, it has been demonstrated the fully running of ASE using renewable energy and residual heat from the industry where the samples came from. In this work, the correct selection and treatment of the different material used in the ASEC systems were successfully applied to the treatment of the samples.

• How did you do quality control (QC) and quality assurance (QA) on the obtained data to validate the conclusions?

Quality control and quality assurance were ensured by the laboratory where analyses were carried out (ICMAN- Instituto de Ciencias Marinas de Andalucía, CSIC- Consejo Superior de Investigaciones Científicas/ Spanish National Research Council). Also the system efficiency and processess are endorsed by the World International Patent Organization: EP3135635, and the Bureau Veritas certification (ECA, 343ct081-6319925, Inform 1-08-41-E5S-1-1-000130), with data and samples presented in the manuscript.

• Based on the data obtained, what are the implications of this work (a) to the field of study, (b) to industry, (c) economy, and/or (c) to the wider public/society in general?

Following reviewer´s suggestion, that information can be found in the manuscript […]The ASEC technology can work as the hub for the efficient water use transition for the textile industry.  […] It reached important keys in the water print conversion of the textile industries (zero liquid discharges, reusable huge volumes of water) avoiding the contamination of water bodies (zero contaminant discharges in the environment).[…] These are objectives of the European Green Deal (clean and circular economy, protection of nature, green change, and elimination of pollution) and the United Nations Sustainable Development Goals. […] Industries would be benefited from important economical savings from water usage, residue management, and the possibility to obtain new sustainable awards.[…]

and in sections 3.4 and 3.5. where economic revenues, and ecological implications are further detailed.

• Please develop the adverse effect of textile organic dye pollutants on environmental pollution based on the following works:
• https://doi.org/10.1016/j.jmmm.2018.02.067
• https://doi.org/10.1016/j.ultsonch.2018.06.003

Following reviewer´s suggestion, indications were introduced

• Check the format of all references and write them in the same format.

Following reviewer´s suggestion, references were checked and modified.

 

Comments on the Quality of English Language

The text is not free of grammar, punctuation, spacing, and syntax errors. Ensure that your English manuscript is guaranteed free of language issues. 

Following reviewer´s suggestion, mistakes were amended, and language was reviewed

Reviewer 3 Report

Please find enclosed my comments on the manuscript number water-2603532 entitled "Towards a cleaner textile industry: the liquid residue treatment challenge" submitted for publication in Journal of Water. The topic sounds interesting. However, it is needed to do a major revision before consider to publish in this journal.

 

1.       The structure of the last paragraph of the introduction is not good and should be summarized. Please only show the novelty of the research in this paragraph.

2.       Statistical analysis should be added in material and method and results section.

3.       Add more comparisons to other researches in Results and Discussion section.  

4.       Conclusion should be revised. It is too long.

5.       The English language of manuscript should improve.

The English language of manuscript should improve.

Author Response

#Reviewer 3

1. The structure of the last paragraph of the introduction is not good and should be summarized. Please only show the novelty of the research in this paragraph.

Following reviewer´s suggestion, the last paragraph of the introduction was modifies and novelty of research was introduced.

2. Statistical analysis should be added in material and method and results section.

The number of samples is not enough for proper statistical analyses.

3. Add more comparisons to other researches in Results and Discussion section.  

Following reviewer´s suggestion comparison with other researches have been included with new references.

4. Conclusion should be revised. It is too long.

Following reviewer´s suggestion, the conclusion was shortened, but specified with other data following a previous reviewer.

5. The English language of manuscript should improve.

Following reviewer´s suggestion, English was reviewed by experts.

Round 2

Reviewer 1 Report

The authors have revised the Manuscript in accordance with the reviewer's suggestions. I have no further comments on this now. In my opinion the current version of the Manuscript is suitable for publication in Water.

Reviewer 2 Report

The manuscript is currently in good shape, and it can be published in this journal.

Reviewer 3 Report

This paper can be accepted.