Study on the enhancement of low carbon-to-nitrogen ratio urban wastewater pollutant removal efficiency by adding sulfur electron acceptors

Erming Luo; Jia Ouyang; Xinxin Zhang; Qian Lu; Dong Wei; Yongcheng Wang; Zhengjiong Cha; Chengwei Ye; Chun ying Li; Li Wei

doi:10.1371/journal.pone.0310222

Peer Review History

Original SubmissionJanuary 15, 2024
4 Jun 2024 Decision Letter - Guanglei Qiu, Editor PONE-D-24-01884Study on the Enhancement of Low Carbon-to-Nitrogen Ratio Urban Wastewater Pollutant Removal Efficiency by Adding Sulfur Electron AcceptorsPLOS ONE Dear Dr. Wei, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Be sure to: Indicate which changes you require for acceptance versus which changes you recommend Address any conflicts between the reviews so that it's clear which advice the authors should follow Provide specific feedback from your evaluation of the manuscript ============================== Please submit your revised manuscript by Jul 19 2024 11:59PM. 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Thank you for stating the following in the Acknowledgments Section of your manuscript: [This study was supported by the Basic and Applied Basic Research Project of the Natural Science Foundation of Heilongjiang Province of China（Grant No.LH2019E068），the Guangzhou Municipal Science and Technology Project(Grant No.202201011743; Grant No.202201011683; Grant No.202201011584；Grant No.2024A03J0392), the International Science and Technology Cooperation Project of the Guangzhou Economic and Technological Development Zone (Grant No.2020GH04), and the zengcheng Innovation and Entrepreneurship Support Program for Leading Talents of Guangzhou City (Grant No.2017012), the livelihood science and technology project of Nansha District, Guangzhou (Grant No.2021MS017).] We note that you have provided funding information that is not currently declared in your Funding Statement. However, funding information should not appear in the Acknowledgments section or other areas of your manuscript. 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The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Partly Reviewer #2: Yes ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: No Reviewer #2: No ****** 3. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes Reviewer #2: Yes ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: No Reviewer #2: Yes ****** 5. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: Manuscript Number: PONE-D-24-01884 Title: Study on the Enhancement of Low Carbon-to-Nitrogen Ratio Urban Wastewater Pollutant Removal Efficiency by Adding Sulfur Electron Acceptors Comment 1: The abstract part seems shallow; not addressed the main points of the study. Comment 2: in introduction part, you provided general issues about C/N. its better if you concentrated on the reality of your study areas. The introduction part also required to summarize more than this. Comment 3: on line 138, you stated figure 1. But there wasn’t it Comment 4: Your research design and methodology the way of sample collection and preservation needs modification Comment 5: the style you wrote the equations not followed the standard Comment 6: your result description wasn’t smart. It needs modification Comment 7: would you followed the reference writing style of PLOSE ONE? Reviewer #2: This study evaluated the removal efficiency of characteristic pollutants during wastewater treatment before and after using sodium sulfate as an electron acceptor in a simulated urban wastewater treatment plant (WWTP) bioreactor. However, the manuscript was not clearly illustrated, and some information is missing. The specific comments and suggestions are as follows. 1. The figures in this manuscript seems very blur. 2. What is the organic matter used for the synthetic wastewater preparation? 3. What is the “The necessary trace elements” added to the domestic wastewater? 4. In my opinion, it is better to add a table to show the operational parameters for phase I and II. 5. What is the meaning of “dynamic changes”? 6. The writing English should be improved. 7. Why did the authors add polyurethane fillers to the aerobic reactor? ****** 6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). 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Revision 1
24 Jul 2024 Author Response Response to Reviewers Dear Editors and Reviewers, The enclosed manuscript entitled “Study on the Enhancement of Low Carbon-to-Nitrogen Ratio Urban Wastewater Pollutant Removal Efficiency by Adding Sulfur Electron Acceptors” is a revised submission (Manuscript Number: PONE-D-24-01884). Many thanks to the editor and reviewers for their valuable comments on the paper. So we have made substantial changes to it, including the language and writing, the introduction, and logical description. All the authors wish it could be considered for publication in PLOS ONE. The comments from the editor/reviewers and the response to editor/reviewers are described as follows, Journal Requirements: 1.When submitting your revision, we need you to address these additional requirements. Reply: OK，additional requirements has been addressed rightly 2＆3.We note that the grant information you provided in the ‘Funding Information’ and ‘Financial Disclosure’ sections do not match. funding information should not appear in the Acknowledgments section or other areas of your manuscript Reply:Funding Information has been removed from the manuscript and update in cover letter. 4.We note that your Data Availability Statement is currently as follows: [All relevant data are within the manuscript and its Supporting Information files] Reply:yes , I confirmed that my submission contains all raw data required to replicate the results of your study Reviewer #1: 1) The abstract part seems shallow; not addressed the main points of the study. Reply: → ‘We had modified the Abstract to highlight the purpose of this article, the experimental approach, the results and future research..’ 2) In introduction part, you provided general issues about C/N. its better if you concentrated on the reality of your study areas. The introduction part also required to summarize more than this. Reply: → the reality of your study areas has been Added into the introduction and the logical description in introduction had been modified . 3) on line 138, you stated figure 1. But there wasn’t it Reply: → figure 1 was added on the bottom of manuscript(line 883) 4) Your research design and methodology the way of sample collection and preservation needs modification Reply: → The design and methodology the way of sample collection and preservation has been revised in the manuscript. ‘2.2 Inoculation sludge and synthetic sewage In this study, the inoculated sludge came from a sewage treatment plant in Nansha, Guangzhou, which operated stably for a long time. Before the sludge was inoculated, the sludge was cleaned to remove impurities in the sludge. 5L of anaerobic sludge was inoculated in each of the two UASB bioreactors with a sludge concentration of about 4000 to 5500 mg / L. At the same time, 3L aerobic sludge was inoculated in the aerobic reactor and 30% polyurethane fillers was added to the aerobic sludge for mixing. In order to investigated the purification capacity of bioreactor to low C / N urban sewage, Synthetic low C/N ratio wastewater prepared with tap water was used in this experiment. Ingredients included C6H12O6(carbon source, 110 mg COD/L); NH4Cl(source of NH3-N,25mg N/L); NaH2PO4(source of P, 1.15mg P/L). At the same time, 1.0ml/L trace elements concentrate was added to the domestic wastewater[24]. The trace element concentrate is composed of :EDTA 5000 mg/L，FeCl 2 3000 mg/L，MnCl2·4H2O 1000mg/L, ZnCl2·7H2O 450 mg/L, CuCl2 ·5H2O 270 mg/L， NiCl 2 ·6H 2 O 200 mg/L ， CoCl 2 ·6H 2 O 240 mg/L. 2.3 Chemical analysis All samples of the water were filtered through 0.45μm filter paper before analysis. COD concentration using COD rapid measurement analyzer (DR1010,HACH, USA). Ammonia nitrogen (NH4+-N) was measured by ammonia nitrogen tester (5B-3N, LianHua, China). The nitrite nitrogen (NO2--N), nitro nitrogen (NO3--N), total , Sulfate (SO42--S) and the sulfide (S2--S) was measured using a multi-parameter analyzer (DR3900, HACH, USA). The WTW real-time water quality testing equipment (Multi 3420, WTW, Germany) was used to monitor the pH and temperature.All water samples were measured in triplicate.’. 5）the style you wrote the equations not followed the standard Reply: → The equations has been revised in the manuscript.For example （1） ΔG= -120.1kJ/mol 6）your result description wasn’t smart. It needs modification Reply: → The logical description and structure of result has been revised in the manuscript. 7）would you followed the reference writing style of PLOSE ONE? 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27 Aug 2024 Decision Letter - Guanglei Qiu, Editor Study on the Enhancement of Low Carbon-to-Nitrogen Ratio Urban Wastewater Pollutant Removal Efficiency by Adding Sulfur Electron Acceptors PONE-D-24-01884R1 Dear Dr. Wei, We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Guanglei Qiu Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation. Reviewer #2: All comments have been addressed ******** 2. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #2: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #2: Yes ****** 4. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #2: Yes ****** 5. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #2: Yes ****** 6. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #2: The authors have revised the manuscript according to the reviewers' comments and suggestions. However, the figures were still blur. Please provide sharp figures before final publication. ****** 7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #2: No ******** https://doi.org/10.1371/journal.pone.0310222.r003
Formally Accepted
14 Oct 2024 Acceptance Letter - Guanglei Qiu, Editor PONE-D-24-01884R1 PLOS ONE Dear Dr. Wei, I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now being handed over to our production team. At this stage, our production department will prepare your paper for publication. This includes ensuring the following: * All references, tables, and figures are properly cited * All relevant supporting information is included in the manuscript submission, * There are no issues that prevent the paper from being properly typeset If revisions are needed, the production department will contact you directly to resolve them. If no revisions are needed, you will receive an email when the publication date has been set. At this time, we do not offer pre-publication proofs to authors during production of the accepted work. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few weeks to review your paper and let you know the next and final steps. Lastly, if your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. If we can help with anything else, please email us at customercare@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Guanglei Qiu Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0310222.r004

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