Municipal-to-Industrial Water Reuse via Multi-Stage and Multi-Pass Reverse Osmosis Systems: A Step from Water Scarcity towards Sustainable Development
Round 1
Reviewer 1 Report
The manuscript that I was asked to assess is devoted to municipal-to-industrial water reuse via multi-stage and multi- 2 pass reverse osmosis systems. The manuscript will not represent interest to the readers since it reports rather trivial results. In their conclusions, the authors do not perform comparisons with the competitive solutions.
Author Response
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Author Response.pdf
Reviewer 2 Report
Please, see attached file. Minor corrections are suggested.
Comments for author File: Comments.pdf
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
Refer to attached pdf.
Comments for author File: Comments.pdf
Author Response
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Author Response File: 
Author Response.docx
Reviewer 4 Report
The paper titled “Municipal-to-industrial water reuse via multi-stage and multipass reverse osmosis systems: a step from water scarcity towards sustainable development” and written by Shih-Shuo Chan and Jung-Hua Wu is interesting and reports a RO system configuration able to produce high quality permeate to be reused from treated wastewater. The paper in general is well written and structured. I recommend a minor revision based on the following comments:
- Page 2, line 48. Meaning of ERFs. I know it is written in the abstract but, it should be also written in the paper itself
- Page 2, line 63. The authors wrote about the problem of boron rejection by RO systems. Beside the aspects mentioned by the authors such as pH adjustment to increase boron rejection, they should also mention that boron permeation could be increased due to fouling along the operating time as well as de operating conditions, this statement could be support by some references about boron rejection behavior in full-scale SWRO desalination plants and boron rejection in SWRO system under variable operating conditions.
- Page 3, lines 103-106. Authors should not mention results in the section Material and methods.
- Page 3, line 112, kilometers should be abbreviated to km.
- Figure 2 shows a flow diagram of the pilot plant. Why the authors did not recirculate the brine of the second pass to the feed?
- The authors should show the impact of the proposed pilot plant in terms of performance. I mean:
- First, seawater RO membrane is used instead of brackish water RO membrane due to have higher boron rejection ratio but, the problem is the high specific energy consumption in comparison with BWRO membrane.
- Second, 2 passes decrease the flux recovery as well as the performance of the plant in terms of water production. Did the authors evaluate to use BWRO membrane in the second stage? Or they wanted to remove maximum of boron concentration?
- What was the flux recovery of the plant B? and the specific energy consumption?
- Did the authors find any issues about organic fouling in the RO system?
Author Response
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Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
The response provided by the authors is irrelevant to the posed criticisms.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
The initial recommendations have been carefully considered. However, the data presentation would benefit from some fine-tuning, such as improved readability of embedded texts, consistent figure legend writing, and clearer figure and table titles. Also, check for some typographical errors.
Author Response
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Author Response File: Author Response.pdf
Round 3
Reviewer 1 Report
The manuscript reports very trivial results. It will unlikely interest a broad readership of Water. Furthermore, the manuscript is poorly written, e.g. "... We propose using measurements of electrical conductivity (EC) as a proxy for boron concentration. We tested our approach to boron estimation and the proposed split partial second pass (SPSP) system at an established WRRF and a pilot plant we constructed at the same location. Results showed that boron in the effluent was directly related to the concentration of EC.... " What is concentration of electrical conductivity? I do not find a work written in such a way suitable for publication.
