Pulp and Paper Mill Fly Ash: A Review

Round 1

Reviewer 1 Report

This manuscript reviews the properties of fly ash from pulp and paper mill and the possible applications of it. The manuscript is well-organized and well written. Please check the following points to improve the quality of the manuscript.

1. In line 47

Further, high pH and pore water electrical conductivity of wood~~

Pore --> poor ??

2. In line 82 and 83, it is mentioned as:

The white liquor is passed through filters and reused in the boiler unite for digestion process.

It might be misunderstood like that the white liquor is used in the boiler.

How about modifying the sentence like:

The white liquor is passed through filters and reused in the digestion process for pulping.

3. In Figure 1, type of line in plot and that in legend box are not matched (check *PPFA(Experimental data)).

Dash-dot format is used in the legend box while solid line is used in the plot for PPFA (Experimental data). Please correct it.

4. In line 136, it is written as:

~~ K, Na, and carbonate (CO32-)

Please correct “CO32-“

5. What is the source of the fry ash in fig. 2? It will be great if the source of the PPFA in fig. 2 is mentioned. At least, it will be an idea to put a reference in Fig. 2.  

In left side SEM picture, a debris of wood fiber is shown, which looks like vessel.

6. Lines 250-252, the sentences:Please consider that these sentences are necessary in this position of this manuscript.

"Authors should discuss the results and how they can be interpreted in perspective of previous studies and of the working hypotheses. The findings and their implications should be discussed in the broadest context possible."

Author Response

Please see the attached document.

Author Response File: Author Response.docx

Reviewer 2 Report

The authors have done excellent job on explaining fly ash and the pulping process. They have provided detailed overview of PPFA characteristics and its applications in different fields. The most important thing is to analyze previous data and suggest how to economically commercialize the usage of PPFA. The authors are encouraged to include this information in the summary section. This article will be a good contribution in the scientific field after making the corrections listed in this review.

The authors have included their experimental data only at one place (Figure 1) without any information on samples, experimental methods and equipment used. I would suggest that authors either add their experimental data in all tables and figures or completely remove it and just focus on literature references. The partial information seems odd.

Comments for author File: Comments.pdf

Author Response

Please see the attached document.

Author Response File: Author Response.docx