Study on the Influential Factors of CO2 Storage in Low Permeability Reservoir
Round 1
Reviewer 1 Report
Overall, the work is worth publishing in the Special Issue of CO2 Injection and Storage in Reservoir in Energies. However, there are some minor issues need to be addressed before publishing.
On Page 2: Since this work is mainly experimental, the authors may improve the Introduction Section via replacing the review of the advancement of numerical simulations with experimental advancement.
On Page 3: When explaining experimental procedures, I would recommend the authors add more explanatory sentences, such as “We conduct the caprock breakthrough pressure test. The following procedures were adopted…”
On Page 4: Step numbers (5) and (6) were missing.
On Page 4: Section 3.1 needs a major improvement because many necessary info are missing, such as:
- What is threshold breakthrough pressure? Numbers?
- Figures were missing when explaining the results.
- The authors claim that “It has been concluded that…”. But how would the authors conclude so? any evidence or supporting info？
- The statement of “Under the condition of …100 MPa /m (Fig.3)” is not clear as the logics is hard to follow. Advise to rewrite the section.
On Page 5: Section 3.2, The authors need to explain M_CO2stored and other symbols. Is it mass? If so, please state it explicitly.
On Page 6: When the authors are explaining the results such as “when the gas injection rate is 0.7-1.5 PV…”, it is not clear which figure the authors are referring to; therefore, it is hard to follow the results discussion. Please add figure references.
On Page 6: There is a grammar mistake. Should be “Therefore, a low-permeability reservoir is more prone to store CO2.”
On Page 8: There is an incomplete comparison. Should be “At the same storage percentage, the recovery factor of crude oil is higher in a core with higher permeability.”
Author Response
Thank you for reviewing the manuscript, I accept your comments.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Dear Authors
I have finished reviewing your paper and found it to be an interesting work. However, some modifications are required before it can move towards publication. The changes are mainly on the grammatical side and overall structure of the paper. I suggest that the authors consider a revision of their work along with the suggestions that are made in the attached file.
In brief:
- More references are needed to be added to your work. Basically, the introduction has to be improved in terms of discussing the consequences of CO2 leakage from the caprock.
- You need to further highlight the applications and significance of study results.
- Some of the experimental procedure is not well described. Please add the details of test protocols for clarification.
- Results section needs improvement as some of the graphs are not discussed in adequate detail.
- Also, the limitations of the study results should be mentioned.
- There are spelling, grammar, or other forms of formatting problems that has to be fixed.
Best Regards,
Comments for author File: 
Comments.pdf
Author Response
Thank you very much for your careful review, your help and questions have benefited me a lot.
Author Response File: Author Response.pdf
