Size Classification and Material Sorting of Fine Powders with a Deflector Wheel Air Classifier and an Electrostatic Separator
, Annett Wollmann 1, Bernd Benker 2, Alexander Plack 1, Mehran Javadi 1 and Alfred P. Weber 1
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors1.The significance and innovative nature of the study should be clearly stated.
2.The numerical simulation and experimental validation results in Figure 4 should be presented simultaneously on the same plot.
3.In the first part of the CFD simulation study, mesh type and accuracy is a non-negligible issue, but the authors did not explain it accordingly. The authors should add to this part of mesh type and mesh independence verification.
4.The authors should have provided a more comprehensive description of the experimental setup, experimental methods, etc.
5.Figure 6 in the manuscript is so poorly readable that the authors should have redrawn it.
6.In subsection 3.3, ‘Subsequently, by introducing the charged materials into the electrostatic separator, where one electrode is positively charged and the other grounded (cf. Figure 2, No. 3)’, there is a discrepancy between the graphical description and the textual description. Please comb through this manuscript carefully.
Comments on the Quality of English Language
It is noted that your manuscript needs careful editing by someone with expertise in technical English editing paying particular attention to English grammar, spelling, and sentence structure so that the goals and results of the study are clear to the reader.V
Author Response
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Reviewer 2 Report
Comments and Suggestions for Authors1. The introductory section highlights the charging behavior of the particle separation process and corresponds to the second part of the article content. However, a literature review on the structural improvement of the classifier is missing to highlight the innovation of the research in the first part of the paper.
2. In the experimental section, it is suggested to add the diagram of the experimental system, the specific parameter settings of the cfd simulation, and the verification of the grid-independence. It is also suggested to add the characterization of the charging properties of the two materials, or to illustrate the differences in their charging properties by supporting them with relevant references.
3. Please refer to the journal requirements to standardize the format of the references.
4. The content of part 3.2 is too thin. It is suggested to merge it into part 3.1 and add the corresponding experimental validation.
5. Supplement the description of the brass nozzle in section 3.3.1, and add the corresponding schematic diagrams or real photographs.
Author Response
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Reviewer 3 Report
Comments and Suggestions for AuthorsPlease find the review in the attachment.
Comments for author File: Comments.pdf
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Reviewer 4 Report
Comments and Suggestions for AuthorsThis paper presented a study on particle size classification and material sorting of fine powders using an air classifier, which is interesting. There are a few concerns that need to improve suggested as follows.
1, The title is not clear as the air classifier needs to specify. Also, it has not addressed the study of the electrostatic separator which is another part of this study.
2, keywords: it is better to specify the ‘air classifier’.
3, Some places miss references such as at L30-34, L42.
4, Line 54: ‘RODOS-disperser’, a full name should give before using it.
5, Line 56: ‘in the range of a few micrometers to the submicron size’, English? It suggests ‘in a range from micron to submicron’.
6, Figure 1: It is unclear, especially for (2). There is not any dimension. The inlet and the outlet points have not been shown.
7, Line 80: ‘In [9],’ it would be better to give the reference work rather than a reference number. It is hard to know which work is referred.
8, Line 127: Figure 1 and 2 are too simple to show enough details for the study.
9, Line 145: ‘in the outer annular region’, is there any specification in the figure, which could be identified?
10, L151, Equation 2: any reference?
11, Line 196: missing words.
12, L194: in the equation, is it the same s2?
13, L261: ‘separation efficiency’, what is the definition?
14, L268, Figure 4: are these the simulation results?
15, L314, Figure 6(a): ‘circumferential’, is that the ‘tangential velocity’? In the blades, it the radical velocity difference between solids and air more interested?
16, L335, Figure 7: The results are not very clear. Solids separation cannot be seen as for long blades all particles seem to all go outside of the blades, but for short blades all large particles go to the centre.
17, L407: ‘0.75-meter electrodes (cf. Figure 2 No. 3).’, it is not the Figure 2?
18, L448: ‘the mass specific charge’, definition?
Comments on the Quality of English LanguageEnglish needs to improve as there are many errors and mistakes occurred.
Author Response
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Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsFrom the reliability of the experimental design and numerical simulation, as well as the comprehensive analysis of the data, the author has made substantial improvements to the manuscript. The overall quality of the manuscripts has improved significantly. I consider this manuscript is worthy for publication.
Comments on the Quality of English LanguagePlease appropriately revise the language expressions in the "Introduction" and "Results and Discussion" sections to enhance the scientific nature and conciseness of the paper. This will not only help improve the readability of the paper but also enhance its academic quality.
Author Response
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Reviewer 4 Report
Comments and Suggestions for AuthorsThe paper has been improved accordingly and all comments have been addressed. It is seen that more data and figures have been added to the manuscript. However, there are a few further comments shown as follows. Also, the English and the format of the paper need to double check as some errors and mistakes can be found.
1, L342, A new figure is added. In the figure, what is the size of the coarse, medium and fine particles?
2, L348, spelling mistakes of ‘develop’.
3, L350, ‘separation sharpness’, definition still needs to be given.
4, L391, should that be ‘Velocity streamlines of air’?
5, L691, in the caption, description of the positions should give.
Comments on the Quality of English LanguageEnglish and the format of the paper need to double check as some errors and mistakes can be found.
Author Response
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