Reverse Osmosis Coupled with Ozonation for Clean Water Recovery from an Industrial Effluent: Technical and Economic Analyses
, Gabriela Roa-Morales 2,*, Edith Erialia Gutiérrez Segura 2, Vianney Díaz-Blancas 1, Germán Eduardo Dévora-Isiordia 3 and Jesús Álvarez-Sánchez 3
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe work focused on the technical and economic feasibility of the coupling process of ozone oxidation and reverse osmosis for treating food industry wastewater to achieve water recycling, which shows a certain degree of innovation. In particular, the research on the coupling process of activated carbon-catalyzed ozone oxidation (ACO) and reverse osmosis (RO) (ACO-RO) has certain advantages in terms of treatment time and effect. I think the article can be published after being revised. The following are some suggestions for revision.
1.For the description of the treatment process, more bases for the selection of equipment and the determination of operating conditions should be supplemented, such as the reasons for choosing specific models of ozone generators and reverse osmosis membranes and determining their operating parameters (such as pressure, flow rate, etc.).
2.When discussing the pollutant removal effects of different treatment processes, the mechanisms of the removal of various pollutants have not been elaborated in detail.
3.The number of wastewater samples collected in the experiment was limited. Only samples were collected for a period of one month, with four samples collected each month, which was unable to fully reflect the long-term changes and fluctuations in the wastewater quality of this industry.
4.In the economic analysis, only the deterministic cost and revenue factors were taken into account, and a comprehensive assessment and uncertainty analysis of the risk factors during the implementation process of the process were not carried out.
5.Some abbreviations of journal names in the reference list are not standardized enough, and the formats of the publication years of some references are inconsistent when cited. The author is requested to check them.
6.There are some inconsistencies in the units and symbols of physical quantities in some places. For example, when expressing electrical conductivity, two formats, namely "EC (mS/cm)" and "mS/cm", are used simultaneously in the text.
7.Some abbreviations (such as "AC", "RO", etc.) do not have the full name explanations when they first appear in the text.
Author Response
Manuscript MEMBRANES ID: membranes-3389474
REVIEWER 1
The work focused on the technical and economic feasibility of the coupling process of ozone oxidation and reverse osmosis for treating food industry wastewater to achieve water recycling, which shows a certain degree of innovation. In particular, the research on the coupling process of activated carbon-catalyzed ozone oxidation (ACO) and reverse osmosis (RO) (ACO-RO) has certain advantages in terms of treatment time and effect. I think the article can be published after being revised. The following are some suggestions for revision.
1.For the description of the treatment process, more bases for the selection of equipment and the determination of operating conditions should be supplemented, such as the reasons for choosing specific models of ozone generators and reverse osmosis membranes and determining their operating parameters (such as pressure, flow rate, etc.).
RESPONSE: Thank you very much for the comments.
To select the equipment and operating conditions that make up the proposed effluent treatment process at industrial level, we conducted a preliminary study at the laboratory scale and obtained the indicated information in Table 2.
Later, based on the laboratory results, we scaled up and reviewed the equipment that exists on the market to cover the demands previously established in the treatment process proposal.
The purpose of reporting on the equipment and operating conditions was to make known that there is commercial technology that can be used for the proposed process and therefore, it has a technical feasibility of implementation at an industrial level. However, other equipment can be selected to make up the treatment process plant, if it meets the conditions previously established at the laboratory level. The recent version of manuscript contains the explanation on this procedure in lines 232-253.
2.When discussing the pollutant removal effects of different treatment processes, the mechanisms of the removal of various pollutants have not been elaborated in detail.
RESPONSE: Thank you very much for the comments.
The new version of manuscript describes the mechanism of colorants degradation by ozone (lines 299-326).
3.The number of wastewater samples collected in the experiment was limited. Only samples were collected for a period of one month, with four samples collected each month, which was unable to fully reflect the long-term changes and fluctuations in the wastewater quality of this industry.
RESPONSE: Thank you very much for the comments.
The manuscript information is supported by previous information of the effluent. The four samples represent the data variation from previous screening of samples. The recent version of manuscript includes this explanation, lines 141-143. In addition, we collected the effluent samples to establish ranges of quality parameters, with the aim of having a range of variation and knowing the behavior of the treatment process in the face of this range of changes.
Also, the treatment proposal indicated that part of the clean water obtained is recirculated in the feed effluent to maintain a constant range of variation in the feed of the treatment process.
4.In the economic analysis, only the deterministic cost and revenue factors were taken into account, and a comprehensive assessment and uncertainty analysis of the risk factors during the implementation process of the process were not carried out.
RESPONSE: Thank you very much for the comments.
The objective of the manuscript was to show the technical and economic feasibility of implementing at an industrial level a proposal for treating effluent from the a food industry. Therefore, we did not perform a risk factor analysis in this work.
We consider that an economic risk analysis in the implementation of the proposed process implies analyzing operational risks, technological risks, and supplier risks, so it could be the subject of another manuscript.
5.Some abbreviations of journal names in the reference list are not standardized enough, and the formats of the publication years of some references are inconsistent when cited. The author is requested to check them.
RESPONSE: Thank you very much for the comments.
We have reviewed the references in the manuscript and the list and have corrected those that had errors.
6.There are some inconsistencies in the units and symbols of physical quantities in some places. For example, when expressing electrical conductivity, two formats, namely "EC (mS/cm)" and "mS/cm", are used simultaneously in the text.
RESPONSE: Thank you very much for the comments.
We have reviewed the units and symbols of physical quantities in all the manuscript and have corrected the errors.
7.Some abbreviations (such as "AC", "RO", etc.) do not have the full name explanations when they first appear in the text.
RESPONSE: Thank you very much for the comments.
We have reviewed the abbreviations in all manuscript and have reviewed the abbreviation section
Reviewer 2 Report
Comments and Suggestions for AuthorsIn this manuscript, technical and economic criteria were used to evaluate the feasibility of the treatment of an industrial effluent for water recovery and reuse. After a detailed evaluation, the manuscript could be published in Membranes after addressing the following aspects.
1. Please provide specific details, parameters used, and estimated errors for industrial-scale amplification methods.
2. The economic model equations require further clarification.
3. Please distinguish the wavelengths for the red, yellow, and blue colors in Table 2 and Table 3.
4. The membrane surface morphologies of the three treatment methods show significant differences, suggesting a further analysis of the contaminants would be appropriate. The membrane fouling might be more suitable than membrane polarization.
5. Please adjust the aspect ratio of the Figure 4 d and e.
6. How to prove the technical feasibility of the selected industrial-scale equipment for treatment.
Comments on the Quality of English LanguageNone
Author Response
Manuscript MEMBRANES ID: membranes-3389474
REVIEWER 2
In this manuscript, technical and economic criteria were used to evaluate the feasibility of the treatment of an industrial effluent for water recovery and reuse. After a detailed evaluation, the manuscript could be published in Membranes after addressing the following aspects.
- Please provide specific details, parameters used, and estimated errors for industrial-scale amplification methods.
RESPONSE: Thank you very much for the comments.
The parameters used to scale up the process were presented in Table 2. To carry out the scaling, we start from laboratory data and data required at the scale under study; the scaling parameters are related by similarity to sizes or volumes, or flows used at laboratory scale with the industrial scale. For example, the air flow used in ozone treatment with the effluent flow and the effluent flow to be treated at industrial level. Later, according to the data obtained, equipment that is on the market and meets the needs of the industrial scale is sought and adjusted.
The recent version of manuscript contains the explanation on this procedure in lines 232-253.
Regarding to estimate the errors in the scaling up process, we do not understand the comment. If this is referring to the scaling method, of course there is a margin of error, but this is how scaling is done by similarity to determine the size of the equipment required at larger scales, taking as a base a smaller or larger scale.
The purpose of the manuscript is to report that the equipment to form the designed plant is commercially available and that its availability is not a difficulty to the implementation of the process at an industrial level, thus fulfilling one of the factors that make up technical feasibility. However the recent version of manuscript contains further explanation on this topic. Lines 234-254 and Table 5.
- The economic model equations require further clarification.
RESPONSE: Thank you very much for the comments.
We have expanded the explanation of the models used in the economic analysis, lines 264-271.
- Please distinguish the wavelengths for the red, yellow, and blue colors in Table 2 and Table 3.
RESPONSE: Thank you very much for the comments.
We have included the yellow, red and blue dyes at the corresponding wavelengths in Tables 1 and 3
- The membrane surface morphologies of the three treatment methods show significant differences, suggesting a further analysis of the contaminants would be appropriate. The membrane fouling might be more suitable than membrane polarization.
RESPONSE: Thank you very much for the comments.
The new version of manuscript contains principal date of membrane fouling. Lines 376-399
- Please adjust the aspect ratio of the Figure 4 d and e.
RESPONSE: Thank you very much for the comments.
There is no direct relationship between the SEM images and the behavior of water flux (Figure 4d) and salts rejection (Figure 4e), because SEM images showed the membrane surface after of different treatments to expose the degree of fouling of the osmosis membrane due to the salt in the effluent, and Figures 4d and 4e show the percentage of clean water flux and the percentage of salt rejection during treatment with the osmosis membrane.
To avoid confusion, in the new version of manuscript we have separated the figures 4d and 4e as Figure 5 and also expanded the explanation of these figures.
- How to prove the technical feasibility of the selected industrial-scale equipment for treatment.
RESPONSE: Thank you very much for the comments.
The technical feasibility of a process was evaluated in various steps, which were indicated in the manuscript, in the previous version in lines 112-120. However, a further explanation was included in the new version of the manuscript. Lines.113-129.
Reviewer 3 Report
Comments and Suggestions for AuthorsIn this paper, the authors report the results of a comparative study on hybrid membrane processes combining single ozonation (SO) or catalyzed ozonation by activated carbon (ACO) with reverse osmosis (RO). This paper deals with an interesting topic, but I think many parts need to be revised to be published in "Membranes". My detailed comments are as follows:
1. The paragraphs are not properly divided, making the article very difficult to read. In particular, please write the abstract as one paragraph.
2. There are various expressions for the amount, such as "USD 19", "15 USD", and "$1.4 USD", so please use a unified expression.
3. In Equation 2, "MAAR" should be changed to "MARR".
4. It is preferable to express it as "Reverse osmosis" rather than "Inverse osmosis".
5. The experimental conditions should be presented in more detail. In particular, please indicate the manufacturer and product name of the RO membrane and activated carbon used. The authors should also provide detailed specifications of these materials.
6. Please provide detailed explanations of the oxidation mechanisms of ACO and SO with a schematic drawing.
7. (L99) I don't know what "industrial level Th evaluation..." means.
8. Performance results under various operating conditions should be available to accurately compare the characteristics of each process. In addition, the results of cycle tests that can determine the membrane cleaning cycle should be presented.
Author Response
Manuscript MEMBRANES ID: membranes-3389474
REVIEWER 3
In this paper, the authors report the results of a comparative study on hybrid membrane processes combining single ozonation (SO) or catalyzed ozonation by activated carbon (ACO) with reverse osmosis (RO). This paper deals with an interesting topic, but I think many parts need to be revised to be published in "Membranes". My detailed comments are as follows:
- The paragraphs are not properly divided, making the article very difficult to read. In particular, please write the abstract as one paragraph.
RESPONSE: Thank you very much for the comments.
We made some changes to the abstract and adjusted it to a single paragraph.
- There are various expressions for the amount, such as "USD 19", "15 USD", and "$1.4 USD", so please use a unified expression.
RESPONSE: Thank you very much for the comments.
We have reviewed the document and corrected the errors regarding the investment cost.
- In Equation 2, "MAAR" should be changed to "MARR".
RESPONSE: Thank you very much for the comments.
The MAAR was replaced by MARR
- 4. It is preferable to express it as "Reverse osmosis" rather than "Inverse osmosis".
RESPONSE: Thank you very much for the comments.
We have changed Inverse osmosis by Reverse osmosis in all manuscript.
- The experimental conditions should be presented in more detail. In particular, please indicate the manufacturer and product name of the RO membrane and activated carbon used. The authors should also provide detailed specifications of these materials.
RESPONSE: Thank you very much for the comments.
The recent version of manuscript contains more detail of RO system. Lines .440-454
- Please provide detailed explanations of the oxidation mechanisms of ACO and SO with a schematic drawing.
RESPONSE: Thank you very much for the comments.
We included the mechanisms of oxidation processes. Lines 300-326.
- (L99) I don't know what "industrial level Th evaluation..." means.
RESPONSE: Thank you very much for the comments.
L99 was corrected with the word The
- Performance results under various operating conditions should be available to accurately compare the characteristics of each process. In addition, the results of cycle tests that can determine the membrane cleaning cycle should be presented.
RESPONSE: Thank you very much for the comments.
Table 2 includes de operating conditions at laboratory scales, which were used in the scaling up procedure. We included more data of the scaling in Table 5.
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsNone
Reviewer 3 Report
Comments and Suggestions for AuthorsThe authors have carefully revised the manuscript according to the referees’ comments. In my opinion, this manuscript could be accepted for publication in membranes. However, the proper paragraph division in the text needs further improvement.
