Review Reports

Round 1

Reviewer 1 Report

The topic of the work is relevant because it touches on one of the most important issues for mankind - the disposal of industrial waste.

 

1. Literature review mainly consists of contemporary sources. The review is quite detailed and gives a complete picture of the current state of research. The research problem is clearly identified, but the goal is not formulated.
2. The second section describes the research methods and the results of studying the properties of the materials under study (slag, coal ash). The description is detailed and the methods are adequately chosen. The results are also well described and clearly illustrated.

In this section, there are minor errors in the presentation of the results. Some of them are noted below in the remarks.

3. The third section presents the results of the analysis of experimental data. The results are mainly focused on the analysis of various variants of the mixture of the studied materials and its mechanical strength (in compression).
4. The fourth section discusses the results of the performed optimization. Optimization was performed on the basis of experimentally obtained dependencies.
5. The fifth section presents the main conclusions based on the results obtained.

 

Notes:

1. Misprint line 141. The sentence starts with a small letter.
2. Line 160 no dot at the end of the sentence.
3. Figure 3 vertical axis labels are not rotated correctly. The same is in figures 10 and 12.
4. Figure 5. Figure caption (a) needs to be aligned with the others. Apparently you need to correct the size of the picture vertically or paragraph indentation.
5. At the end of the first section, a brief description of the work performed is given. At the same time, the specific purpose of this work should be briefly formulated.

Author Response

Response to Reviewer 1 Comments：

Point1: Misprint line 141. The sentence starts with a small letter.

Response 1:We are very sorry for our incorrect writing. We have corrected the error that the first word of the sentence in 141 lines of the original manuscript is lowercase, which is now located in 147 lines of the submitted manuscript. The original sentence is "gasification slag is the waste slag after high-temperature gasification reaction of coal in the process of coal chemical utilization." and now it is revised to "As a product in the process of coal chemical utilization, gasification slag is the waste residue produced by coal gasification reaction at high temperature."

Point2: Line 160 no dot at the end of the sentence.

Response 2:We are very sorry for our incorrect writing. We have corrected the error that there is no full stop at the end of the sentence on line 160, which is now located on line 166 of the manuscript. We have made correction according to the Reviewer’s comments. In the submitted manuscript, we re worded and revised the 15-18 long sentences in the abstract on page 1. The original sentence is "At the same time, the method specified in the "Standard for Geotechnical Test Methods" was adopted (GB/T 50123-2019), the main chemical component was kaolinite, accompanied by quartz, and the XRD analysis is shown in Fig. 5(b)" and now it is revised to "Meanwhile, the method specified in the standard for test methods of Geotechnical Engineering (GB/T50123-2019) shall be used as the benchmark. The main chemical component was kaolinite, accompanied by quartz, and the XRD analysis is shown in Figure 5(b)."

Point3:Figure 3 vertical axis labels are not rotated correctly. The same is in figures 10 and 12.

Response 3:We are very grateful to the editors and reviewers for their valuable comments. The vertical axis labels in figures 3, 10 and 12 of the original manuscript are not rotated correctly. We have completed the modification in the revised manuscript.

Point4: Figure 5. Figure caption (a) needs to be aligned with the others. Apparently you need to correct the size of the picture vertically or paragraph indentation.

Response 4:We are very grateful to the editors and reviewers for their valuable comments. We corrected the vertical size of the picture on Figure 5. Figure caption (a) in the original manuscript, and completed the alignment of the title.

Point5: At the end of the first section, a brief description of the work performed is given. At the same time, the specific purpose of this work should be briefly formulated.

Response 5：We are very grateful to the editors and reviewers for their valuable comments. We added the specific purpose of this section at the end of the first section in the revised manuscript. The main purpose of this section is to design the factors affecting the performance of the filling body based on the box Behnken design of response surface method, as shown in Table 1. In order to get a more in-depth and rigorous experimental scheme, different gradient numerical arrangements were made for the four design factors.

Author Response File: Author Response.pdf

Reviewer 2 Report

The topic of the article relates to the relevant direction in the development of new structural materials with reduced cost and improved performance. However, multiple inaccuracies in the article do not allow a full assessment of its scientific content. Before reviewing, a thorough proofreading of the article should be carried out and such shortcomings as not introduced abbreviations (even in the abstract), the beginning of paragraphs with capital letters and inconsistent sentences should be corrected. Only after that the article can be re-examined  by the reviewer.

Author Response

Response to Reviewer 2 Comments

Point 1: The topic of the article relates to the relevant direction in the development of new structural materials with reduced cost and improved performance. However, multiple inaccuracies in the article do not allow a full assessment of its scientific content. Before reviewing, a thorough proofreading of the article should be carried out and such shortcomings as not introduced abbreviations (even in the abstract), the beginning of paragraphs with capital letters and inconsistent sentences should be corrected. Only after that the article can be re-examined by the reviewer.

Response 1:We are very grateful to the editors and reviewers for their valuable comments. We have made correction according to the Reviewer’s comments. We have proofread the article and corrected the lack of abbreviations (even in the abstract), the use of capital letters at the beginning of paragraphs, and inconsistencies in sentences.

 

Author Response File: Author Response.pdf

Reviewer 3 Report

 

Comments to the Authors:
The authors of this paper present an interesting investigation on the use of  fly ash instead of the crushed gangue as the filling proportion material aggregate, in order to reduce crushing cost and energy consumption. However, some details should be considered by the authors:

GENERAL COMMENT: Please check the punctuation throughout the text.

GENERAL COMMENT: English should be checked throughout the text.

GENERAL COMMENT: The abstract is a bit long and not helpful for the readers. Thus, it could be reduced/rewritten by the authors.

COMMENT: Page 1, Abstract, lines 15-18: Long sentence. Please rephrase.

COMMENT: Page 1-2, Introduction, lines 43-49: Long sentence. Please rephrase.

COMMENT: Page 2, Introduction, line 83: More recent references should be added.

COMMENT: Page 2, Introduction, lines 90-95: Long sentence. Please rephrase.

COMMENT: Page 4, Fig. 2: Since photos of the instrumentation used are shown in this paper, I also suggest the authors to add some experimental details/parameters used for the measurements acquitision.

COMMENT: Page 5, Fig. 5: The XRD patterns are hardly seen. For the patterns shown in Fig. 5c & d the signal-to-noise ratio is relatively low and several peaks are unidentified/not commented.

COMMENT: Page 6, lines 189-196 and Table 1(page 7): Long sentence. Please rephrase. Also, the results shown in Table may be further commented.

COMMENT: Page 8, Fig. 8: The caption should be corrected.

COMMENT: Page 12, Fig. 12: “Influence analysis of strength response surface factor interaction on 3 d”. What about the analysis on 7 d ?

This work is interesting, however it deserves publishing after major revision.

 

Author Response

Response to Reviewer 3 Comments

Point 1: Please check the punctuation throughout the text.

Response 1:We are very grateful to the editors and reviewers for their valuable comments. We are very sorry for our incorrect writing. We checked the punctuation marks of sentences in the manuscript in detail and completed the modification.

Point 2: English should be checked throughout the text.

Response 2:Thank you for your valuable and thoughtful comments. We have carefully checked and improved the English writing in the revised manuscript. We have revised the English expression of the whole text, including punctuation and the use of more concise short sentences.

Point 3: The abstract is a bit long and not helpful for the readers. Thus, it could be reduced/rewritten by the authors.

Response 3:

We have re-written this part according to the Reviewer’s suggestion. The number of some words was reduced from 307 to 264. We rewrote the conclusion of the abstract and abridged the research methods and purposes of the article in order to make the abstract more concise. “In order to solve the problem of high cost of coal-based solid waste bulk stacking and paste filling in the large-scale coal electrification base in the east of Ningxia. In this paper, fly ash is skillfully used to replace the broken coal gangue as the filling mix material. As a jaw crusher for crushing large coal gangue, its cost is expensive and its energy consumption is relatively high. The paste filler with fly ash as aggregate is studied through micro and macro test analysis. Using response surface methodology design software, 29 groups of mix proportion schemes are designed to obtain the best mix proportion. Meanwhile, the radar results of slump, slump flow and comprehensive strength are obtained by normalization method. According to the radar chart results of the three normalized indexes, the optimal ratio parameters are as follows: fly ash in solid is 79 % , the mass of fly ash: the mass of cement(FA: C)is 6:1, the solid mass concentration is 78 %, fly ash: gasification slag is 1:1, and the result shows: σ_3d=2.20 MPa, slump=205 mm and flow=199 mm. Taking solid mass concentration, FA:C, fly ash content in solid and coal gangue: gasification slag as independent variables, the influence of single factor and multi factor interaction of independent variables was analyzed based on response surface model. It is found that the solid mass concentration and FA:C have a very significant effect on the early strength. Replacing coal gangue base with fly ash base can effectively reduce crushing cost and energy consumption, and provide low-cost and high reliability technical reserves for large-scale filling.”

Point 4: Page 1, Abstract, lines 15-18: Long sentence. Please rephrase.

Response 4:We have made correction according to the Reviewer’s comments. In the submitted manuscript, we re worded and revised the 15-18 long sentences in the abstract on page 1. The original sentence is "In order to solve the problems of bulk coal-based solid waste storage, high paste filling cost in East Ningxia large coal electrification base, fly ash was skillfully used to replace the crushed gangue as the filling proportion material aggregate,while high energy consumption and high cost in the crushing of large-size gangue by a jaw crusher." and now it is revised to " In order to solve the problem of high cost of coal-based solid waste bulk stacking and paste filling in the large-scale coal electrification base in the east of Ningxia. In this paper, fly ash is skillfully used to replace the broken coal gangue as the filling mix material."

Point 5: Page 1-2, Introduction, lines 43-49: Long sentence. Please rephrase.

Response 5:We are very grateful to the editors and reviewers for their valuable comments. In the submitted manuscript, we re worded and revised the 43-49 long sentences in the introduction on page 1-2. The original sentence is "East Ningxia Coal and Electricity Base is one of the 14th hundred million-tons coal bases,from the perspective of East Ningxia Coal and Electricity Base, with the rapid development of the modern coal chemical industry, the ecological risk level of the coal industry Base in East Ningxia urgently needs to be effectively controlled(Wang et al. 2013), industrial solid waste, mainly fly ash, gasification slag, coal gangue, desulfation gypsum, and bottom slag, have increased rapidly." and now it is revised to "East Ningxia Coal and Electricity Base is one of the 14th hundred million-tons coal bases. From the perspective of East Ningxia Coal and Electricity Base, with the rapid development of the modern coal chemical industry, the ecological risk level of the coal industry Base in East Ningxia urgently needs to be effectively controlled(Wang et al. 2013). Industrial solid waste, mainly fly ash, gasification slag, coal gangue, desulfation gypsum, and bottom slag, have increased rapidly."

Point 6: Page 2, Introduction, line 83: More recent references should be added.

Response 6: We tried our best to improve the manuscript and made some changes in the manuscript. These changes will not influence the content and framework of the paper. We added two references in 2021 and 2022 to line 83 of the introduction on page 2, that is, we modified lines 78 and 86 in the manuscript. The original reference is "Coal gangue as aggregate has been used to study the mechanical properties of the filling body through uniaxial and triaxial tests(Zhang et al. 2012); Coal gangue with a particle size of about 5mm as aggregate, and various methods to prepare coal gangue conglomerate-like paste filling materials and their related properties has been obtained(Cui et al. 2010)." and now it is deleted and added as "A three-dimensional simulation method for the compaction fracture of crushed rock and coal particles is proposed, and the effects of the strength and size of crushed samples on the fracture characteristics and stress evolution of the crushing model during loading are further discussed.(Zhang et al. 2021); This study focuses on the method of estimating the load and strength of the pillar system, points out the main factors for evaluating the stability of the coal pillar, and concludes that the failure criterion of the coal pillar is an important factor for calculating the strength of the coal pillar(Zhang et al. 2022)."

Point 7: Page 2, Introduction, lines 90-95: Long sentence. Please rephrase.

Response 7: We are very grateful to the editors and reviewers for their valuable comments. In the submitted manuscript, we re worded and revised the 90-95 long sentences in the introduction on page 2. The original sentence is "According to the statistics of the power consumption of crushing operations accounts for more than 50 % of the total power consumption of the concentrator, and the total power consumption for crushing operations in the country is more than 2×10⁹kW*h(Li et al. 2009), as the cost of crushing coal gangue becomes higher, the utilization energy consumption is large, and the particle size requirements are high, it is no longer conducive to anemission reduction and economic effects." and now it is revised to "According to the statistics of the power consumption of crushing operations accounts for more than 50 % of the total power consumption of the concentrator. And the total power consumption for crushing operations in the country is more than 2×10⁹ kW*h(Li et al. 2009). With the increase of the crushing cost of coal gangue, the energy consumption becomes larger and the particle size requirement becomes higher, which is no longer conducive to emission reduction and economic benefits."

Point 8: Page 4, Fig. 2:Since photos of the instrumentation used are shown in this paper, I also suggest the authors to add some experimental details/parameters used for the measurements acquitision.

Response 8: We have made correction according to the Reviewer’s comments. We added some experimental detail parameters for measuring acquisition to the instrument used in Figure 2, which are located in lines 120-125 of section II of the revised manuscript.

Point 9: Page 5, Fig. 5:The XRD patterns are hardly seen. For the patterns shown in Fig. 5c & d the signal-to-noise ratio is relatively low and several peaks are unidentified/not commented.

Response 9: We are very grateful to the editors and reviewers for their valuable comments. We did not comment on several peaks in several XRD figures in Figure 5 on page 5, for the purpose of explaining the main components of the filling raw materials. We also analyzed and plotted the XRD pattern shown in Figure 5d.

Point 10: Page 6, lines 189-196 and Table 1(page 7):Long sentence. Please rephrase. Also, the results shown in Table may be further commented.

Response 10: We are very grateful to the editors and reviewers for their valuable comments. In the submitted manuscript, we re worded and revised the 189-196 long sentences in the introduction on page 6. At the same time, we reword the title of Table 1. And further comment on the results and contents shown in the table. Our revised sentence is “By reading relevant documents (Yan et al.2007; sun et al.2012), combined with the characteristics of large coal-based solid waste storage yard in the mining area of the eastern base of Ningxia. These characteristics mainly include fly ash, gasification slag and coal gangue. And after comprehensively considering the cost of bulk crushing of coal gangue and the performance requirements of coal-based solid waste filler, the coal gangue with particle size less than or equal to 16 mm after crushing is used, supplemented by fly ash as aggregate.And the experimental factors and levels shown in Table 1 are obtained.

Based on the Box-Behnken design method of response surface method, the following design is made for the factors affecting the performance of filling body, as shown in Table 1. Different gradient numerical arrangements are made for the four design factors in order to get a more in-depth and rigorous experimental scheme.” 

Point 11: Page 8, Fig. 8: The caption should be corrected.

Response 11: We have made correction according to the Reviewer’s comments. We correct the title of figure 8 on page 8. The original title is "Statistical histogram of compressive strength at different ages" and now the title is "Fracture morphology of mix proportion test block at three days of age under different schemes". This picture mainly shows the fracturing morphology of 3d early filling body, demonstrates the accuracy of the compressive strength data in this paper from many aspects, and describes some crack propagation morphology. The content added about figure 8 is "According to the calculation of the mean value of 3 d compressive strength of the above filling body, this paper divides the compressive strength data of 29 groups of three-day design schemes into four gradients, as shown in Figure 8. By comparing the divided compressive strength range with the strength of the optimized proportioning scheme, the reliability of the optimized proportioning scheme is further improved. According to the failure characteristics of the test block at the age of 3 d, the brittleness of the test block is large, the surface block falls off greatly during fracture failure, and the development of cracks after failure is chaotic.".

Point 12: Page 12, Fig. 12: “Influence analysis of strength response surface factor interaction on 3 d”. What about the analysis on 7 d ?

Response 12: We have made correction according to the Reviewer’s comments. At the same time, we also analyzed the 7 d two factor interaction regression model. This is to demonstrate the two factor interaction model under 3 d early compressive strength. Through the 7 d regression model, we can see that it is consistent with the regression model under 3 d age. As shown in Figure 13 (a), (b) and (c), the solid mass fraction has a significant effect on the compressive strength.

 

 

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

 

The manuscript has been substantially improved by the authors and since the reported data are discussed and commented, I think that this paper may be published. However, English and punctuation should be checked again throughout the text.

Author Response

Dear Sustainability editors and reviewer,

We appreciate for Editors and Reviewers’ warm work earnestly, and hope that the correction will meet with approval.

On behalf of all the authors, I am pleased to submit the details of the revisions to the manuscript and your responses to the references' comments for your appreciation, such that any changes can be easily viewed by the editors and reviewers. We downloaded the latest manuscript from the link. In the latest submission, we revised the comments of editors and reviewers. For full-text manuscripts, we use punctuation marks and English letters to express, or even more pure English expressions. We marked it with red and annotations.

Once again, thank you very much for your comments and suggestions.

 

Responds to the reviewer’s comments:

Reviewer :

1-Please check that all references are relevant to the contents of the manuscript.

Answer：We have made correction according to the Reviewer’s comments. In the latest manuscript submitted, we rearranged all references so that they can be clearly displayed in the whole manuscript. Throughout the manuscript, we have mapped references to their contents in the text.

 

 

 

 

Many thanks for your time and consideration.

 

 

Yours sincerely, Denghong Chen

Room A221，School of Mining Engineering, Anhui University of Science and Technology, No. 168 Taifeng Road, Huainan, Anhui Province, P. R. China 232001

Tel:(+86)18155465228  Email:ahhncdh@163.com

Author Response File: Author Response.pdf

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.