Characterisation of a Real-World Søderberg Electrode
, Merete Tangstad 2, Eli Ringdalen 3, Douglas Dall 4, Joalet Dalene Steenkamp 5,6 and Masana Mushwana 5Round 1
Reviewer 1 Report
The manuscript is well-written and practically oriented, and very comprehensive. This study is probably the first of its kind as a published topic.
The abstract is concise and describes the work well.
The introduction describes well the Søderberg electrode process, and the referenced literature is up-to-date. Clear motivation is provided for the present work.
Excellent experimental descriptions were provided.
The DOG measurements: Is this a standard method of measurement used in describing graphitization in industrial carbon materials such as electrodes? Is there an advantage using this over measuring the Lc for example? Some more explanation is required here for the reader.
Figures 5-7: The maps in (b) and (c) are a very nice way to present the data in two dimensions.
Lines 365, 379-381: a more appropriate word is suggested when describing the solid particulate electrode paste component is “aggregate” instead of “filler”.
Errata, improvements in text:
Line 51: should read “...if an electrode break occurs…”
Line 90: “asses” should be corrected to “assess”. :-)
Line 183: “bulked density” should be changed to “bulk density”.
Line 240: should read “3.1. Operational history”.
Line 266: should read “…could be collected on,..”
Line 307: shoud read “…times higher...”
Figure 5: the length scale on (b) should be 2.7 m, not 2.7 cm.
Line 315, 353, 417, 445: “…spatially interpreted…” It is redundant to use the same text about using the “grid data” function in Matlab – you could mention it once in the text for brevity.
Lines 320-326, Table A1: use proper times symbols (´) , not the letter “x”.
Line 372: “opposing” not “apposing”.
Line 472: “strength” not “strenght”.
Author Response
Response to Reviewer #1 comments
Point 1: The manuscript is well-written and practically oriented, and very comprehensive. This study is probably the first of its kind as a published topic.
The abstract is concise and describes the work well.
The introduction describes well the Søderberg electrode process, and the referenced literature is up-to-date. Clear motivation is provided for the present work.
Excellent experimental descriptions were provided.
The authors thank Reviewer #1 for the positive comments.
Point 2: The DOG measurements: Is this a standard method of measurement used in describing graphitization in industrial carbon materials such as electrodes? Is there an advantage using this over measuring the Lc for example? Some more explanation is required here for the reader.
The method for determining DOG in this study is very commonly applied and is well documented in numerous papers published in high impact factor journals. However, we understand that some readers might be used to other methods, which are also commonly applied. Therefore, instead of citing multiple additional papers to prove that there are a couple of methods that can be used, we have added one additional reference ([18]), which specifically refer to three of the most commonly applied techniques to determine DOG. The revised text (manuscript without track changes) in lines 166-168 now reads “The degree of graphitisation (DOG) was determined with the so-called interlayer spacing or d002 method, based on XRD analysis [17]. This method is one of at least three recognised methods to determine DOG [18].”
Point 3: Figures 5-7: The maps in (b) and (c) are a very nice way to present the data in two dimensions.
The authors thank Reviewer #1 for the positive comments.
Point 4: Lines 365, 379-381: a more appropriate word is suggested when describing the solid particulate electrode paste component is “aggregate” instead of “filler”.
The authors agree and have replaced the word “filler” with “aggregate” at 7 locations in the text.
Point 5: Errata, improvements in text:
Line 51: should read “...if an electrode break occurs…”
The authors thank the reviewer for pointing out this oversight, the text has been corrected in the revised version.
Line 90: “asses” should be corrected to “assess”. :-)
The authors thank the reviewer for pointing out this obvious oversight (which made us all smile!). The text has been corrected.
Line 183: “bulked density” should be changed to “bulk density”.
The authors thank the reviewer for pointing out this typo, the text has been corrected.
Line 240: should read “3.1. Operational history”.
The authors thank the reviewer for pointing out this typo, the text has been corrected.
Line 266: should read “…could be collected on,..”
The authors thank the reviewer for pointing out this typo, the text has been corrected.
Line 307: should read “…times higher...”
The authors thank the reviewer for pointing out this typo, the text has been corrected.
Figure 5: the length scale on (b) should be 2.7 m, not 2.7 cm.
This is a very important oversight indicated by Reviewer #1. It has been corrected in all the relevant figures.
Line 315, 353, 417, 445: “…spatially interpreted…” It is redundant to use the same text about using the “grid data” function in Matlab – you could mention it once in the text for brevity.
The authors agree and have removed the repeated text in the captions of the figures and in the main text. In the revised manuscript, a brief explanation is given upon first introduction of the spatial interpolation with Matlab concept, in the main text in lines 292-293. This revised text reads “… were spatial interpolated across the entire investigated area (0.7 to 2.7 m below the contacts shoes), as indicated in Figure 5b. This was done using the “grid data” function in Matlab, with triangulation-based linear interpolation.”
Lines 320-326, Table A1: use proper times symbols (´) , not the letter “x”.
The authors agree and have replaced all “x” with “×” (the multiplication symbol) everywhere in the text and in Table A1.
Line 372: “opposing” not “apposing”.
The authors thank the reviewer for pointing out this typo, the text has been corrected.
Line 472: “strength” not “strenght”.
The authors thank the reviewer for pointing out this typo, the text has been corrected.
Reviewer 2 Report
There are not many studies regarding the operation of the Soderberg electrodes consequently this study is of high significance.
The results are very well presented but some minor changes should be performed. For example, in Fig. 5a, the font size should be increased, while in Fig. 5b the "Unsampled tips" are on the image. Similarly, in Fig. 6a, 7a, 8a the font size should be increased.
The units of the resistivity should use the symbol \cdot.
Author Response
Response to Reviewer #2 comments
Point 1: There are not many studies regarding the operation of the Soderberg electrodes consequently this study is of high significance.
The authors thank Reviewer #1 for the positive comments.
Point 2: The results are very well presented but some minor changes should be performed. For example, in Fig. 5a, the font size should be increased, while in Fig. 5b the "Unsampled tips" are on the image. Similarly, in Fig. 6a, 7a, 8a the font size should be increased.
The authors have increase font sized in Figures 5a, 6a, 7a and b, 8a, as well as 10.
Regarding the "Unsampled tips" text that is positioned on the image in Figures 5b, 6b, 7c and 8b. This was done on purpose, so that the reader can see that the tips were not sampled and characterised. Similarly, the text “Unsampled electrode” is indicated on all these figures in the area below the contact shoes that were not sampled (since it was not removed from the submerged arc furnace). Therefore, with the permission of Reviewer #2, we would prefer to keep the text “Unsampled tips” on the image. But, this comment by Reviewer #2 made us realise that we needed to better indicate to the reader the “unsampled” portions and the associated text. Therefore, we have added the following text where the interpolated figures are introduced first, i.e. Figure 5b that is introduced in lines 292-295 in the revised manuscript. This text now reads “… were spatial interpolated across the entire investigated area (0.7 to 2.7 m below the contacts shoes), as indicated in Figure 5b. This was done using the “grid data” function in Matlab, with triangulation-based linear interpolation. In effect, this representation gives a 3-dimensional (3D) cross section perspective of the investigated electrode, excluding the unsampled electrode area directly below the contact shoes and the uneven electrode tips, with colour indicating the 3rd dimension.”
Point 3: The units of the resistivity should use the symbol \cdot.
The authors thank Reviewer #2 for pointing out this oversight. All the resistivity units are indicated in the revised manuscript as “Ω∙m”.
