Simulation and Dynamic Properties Analysis of the Anaerobic–Anoxic–Oxic Process in a Wastewater Treatment PLANT Based on Koopman Operator and Deep Learning
Round 1
Reviewer 1 Report
Comments:
The manuscript entitled “Simulation and dynamic properties analysis of the Anaerobic-Anoxic-Oxic process in a wastewater treatment plant based on Koopman operator and deep learning” has many grammatical issues that need to be corrected. The authors need to proofread the manuscript thoroughly. I suggest the following changes and improvements:
1. Authors need to improve the abstract section and underscore the scientific value added to your manuscript in your abstract.
2. The current structure of the introduction is not well organized and long. The authors need to be improved. Additionally, the last part needs to be revised considering the main theme/objectives and findings of the study.
3. According to the results, the combination of Koopman operator and deep learning achieves accuracy prediction……… need to revise and eliminate the grammatical issue.
4. The novelty of this work should be stated clearly in the introduction section.
5. What are the current research gap and the significance of this work?
6. These method is able to quickly find the representation and linearized………. Need to be rewritten and eliminate the grammatical issue.
7. Line 129: Eliminate typos issues such as nitrate nitrogen (NO3)
8. Based on the above data, a simulation model for the dynamic of A2O process is constructed using deep learning method. A too short paragraph.
9. Figures 3, 4, and 5: Figures legends should provide enough information. Additionally, improve the quality and care about subscripts such as NO3, NH3, etc.
I mentioned it in the comments section in detail.
Author Response
Authors: Wenchong Tian, Kunlun Xin, Zhiyu Zhang, Zhenliang Liao, and Fei Li.
Dear Editor, Dear Reviewer,
Thanks for your review. We consider the comments and provide a new version of the manuscript through which the originality and significance of the contribution are further articulated. Please find our point-by-point reply below.
Yours sincerely,
Kunlun Xin, Wenchong Tian
College of Environmental Science and Engineering, Tongji University.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The authors developed a new simulation model for A2O process in wastewater treatment. Following revisions were suggested by this reviewer.
1) According to the authors, the frequency for inflow data on water quality parameters were 5 minutes intervals. However, the reviewer thinks that some of the parameters such as TN, TP are very difficult to be monitored with such a high frequency, while nitrate and ammonia can be monitored with sensory devices. Measurement of COD by an authorized method with a high frequency is also difficult. Authors are advised to show the methods for the measurement of water quality parameters. The reviewer thinks that the methods may include simplified methods.
2) Only aeration volume is included in the model. This means the reactor volumes of anaerobic-anoxic-oxic tanks are fixed in the operation. The reactor volumes of three steps in the real wastewater treatment plant has to be shown.
3) The authors mention about the limitations for mechanism-oriented models and conventional data-driven models. However, the reviewer did not understand the advantage of the proposed model based on the results in this study. The reviewer still feels that the model proposed by the authors is still a black-box. Authors are advised to show the advantage based on their results possibly in the conclusion. In addition, the authors mention about the constructed model in the discussion to clarify the contents of the black box.
4) Most of the sentences in the method section and sentences for results have to be written with a past form. For example, "data cleaning is performed " should be "data cleaning was performed" and "extreme outlier data is removed" should be "extreme outlier data were removed". A part of the discussion can be written with a present form. Please follow the general rule of scientific presentation.
Several problems on language were found, while most of the contents can be understood. Please carefully edit the language again.
Author Response
Dear Editor, Dear Reviewer,
Thanks for your review. We consider the comments and provide a new version of the manuscript through which the originality and significance of the contribution are further articulated. Please find our point-by-point reply below.
Yours sincerely,
Kunlun Xin, Wenchong Tian
College of Environmental Science and Engineering, Tongji University.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
I suggest the following minor changes.
1. Lines 17 and 24: Eliminate the space issue throughout the manuscript.
2. Line 20: Avoid capitalization in a sentence throughout the manuscript such as These This methods…..
3. Lines 79-83: Please check the reference format.
4. Lines 127-128: connect the sentence.
5. Please eliminate the typos errors such as Line 183 and 184: wais, Line 185: iis, etc. Authors need to proofread the manuscript thoroughly.
6. Lines 183-187: Need to rephrase and eliminate the grammatical issue.
I mentioned it in the comments section. Additionally, the authors need to proofread the manuscript thoroughly.
Author Response
Dear Editor, Dear Reviewer,
Thanks for your review. We proofread the manuscript thoroughly. Most of the issues are because of the mark in the uploaded version. We uploaded a clean version and all the issues were fixed. Please find our point-by-point reply below.
Yours sincerely,
Kunlun Xin, Wenchong Tian
College of Environmental Science and Engineering, Tongji University.
Author Response File: 
Author Response.pdf
