Energy and Nutrients’ Recovery in Anaerobic Digestion of Agricultural Biomass: An Italian Perspective for Future Applications
Round 1
Reviewer 1 Report
Dear authors,
I read your article, in which you deal with an interesting topic.
In my opinion, a revision appropriate should be done. Please, focus on the following notes:
Figure 1: State the data source.
Tables 1 and 2: Again, the source from where the data were obtained should be listed.
Chapter Results and Discussion (RaD) is a more or less mix of RaD and Introduction.
It should be more obvious which results are original (from author) and that are taken from the literature.
The Conclusion chapter is quite short and it deserves some extension for example of the main study's points.
Author Response
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Reviewer 2 Report
This manuscript described the anaerobic digestion for biogas production in Italy. The heterogeneity of the biogas production by different areas was pointed out. However, this point is not new. Different feedstocks was also analyzed by Biomethane potential test. The third part on different techniques for digestive valorization was not specific to Italy and fall out of the topic of the manuscript. Besides, the manuscript overall was long and lack of logic and structure. It is really hard for readers to grasp the main idea. Besides, the whole manuscript is full of careless grammar and misspelling mistakes. A lot of sentences lack logic. Please see the comments below. Therefore, this manuscript cannot be accepted for publication.
in line 6 in Abstract, “although this encouraging situation” should be changed to “despite this encouraging situation”
In Abstract, when BMP was first introduced, the full name-biomethane potential should be given.
In Table 1 and 2, the dot in numbers should be changed to comma to avoid confusion. For example, “11.178” should be “11,178”.
Where does the data in Figure 1 come from? Proper references need to be included.
In the second paragraph on Page 5, “In 2018 a new Decree came on force with the aim to incentive the biogas valorization in the biomethane”, “incentive” should be changed to “encourage”.
Detailed description in 2.2 Analytical methods should be included in the paper as I have a hard time to find the reference 25 paper.
In 12th line in 2.3 Biomethane potential of substrates, what is “as it is usual n our lab” ? In 16th line, what is “liquid surnatant”?
In Line 8 on Page 2, “as they are not in competition with human nutrition or land degradation.” The logic is wrong.
In Line 15 on Page 9, “concentrate” should be “concentrated”
In Line 9 on Page 11, “or undergoes a solid/liquid separation process to obtain the distinct streams, one liquid and one solid, with different fertilizing characteristics.” What is the subject of the sentence?
Author Response
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Reviewer 3 Report
In this article, the authors provide the perspectives on the energy and nutrients recovery in anaerobic digestion of Agricultural Biomasses. The biogass production, feedstock and the nutrition recovery were discussed in different region of Italy. The article is well organized and of great significance in the field of biorenewable resource. Several minor issues, however, need to be addressed before the article is suitable to be published, as listed below:
1) Figure 1 summarize the number and the power capabilities of biogas plants in different regions. However, the figure is hard to understand for readers who are not familiar with Italian map. Therefore, this Figure is recommended to be coupled with the a map or be better categorized (such as label whether the city is in northern or southern region, as Table 1 shows).
2) The paper has summarized the energy generation from different feedstock in different region. At the same time, the digestion process, along with the planting process, also requires the energy input. Therefore, a overall energy and economic analysis is recommended in different regime to show whether it is a profitable process.
3) Moderate English changes are required (there are several mistakes of grammar). Also, there are several very short paragraphs (1 or 2 sentences) in the introduction part. Please also reorganize this part in a logical sequence.
Author Response
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Round 2
Reviewer 2 Report
It seems that the authors corrected the errors from the last round, but also created some errors in their revised version. See below.
On page 2, there two of the same paragraphs "Italy is an important actor in the depicted scenario: with its 1500 AD plants, mainly in the rural areas, it represents the second European market after Germany and the third in the world after China".
In the third line in last paragraph on page 2, "ive our vision"?
Author Response
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