# Study on the Ash Deposition Characteristics for Co-Combustion of Zhundong Coal with Cotton Stalk
## 4 Conclusions  
In this paper, based on the ash compositions of Zhundong coal and cotton stalks at different mixing ratios, the liquid phase content at different temperatures was calculated by Factsage. An ash deposition model based on the melting ratio of coal ash was established, and the influence of cotton stalk mixing on the ash deposition characteristics of the wall of the corner tangent boiler was analyzed. On this basis, the formation process of wall ash  
Figure 11: Ash deposition rate under tangential circle diameters.  
Figure 10: Ash deposition distribution under tangential circle diameters: **(a)** 1600 mm, **(b)** 1200 mm, **(c)** 800 mm, and **(d)** 400 mm.  
deposition was further analyzed, and the condition of ash deposition on the heating surface was alleviated by reducing the tangential circle diameter, and the simulation calculation was carried out. The main conclusions are as follows:  
1. With the increase in the blending ratio of cotton stalks, the content of K\({}_{2}\)O increased significantly, from 0.31% without mixing to 9.31% when the mixing ratio was 25%. While the contents of CaO, Fe\({}_{2}\)O\({}_{3}\), and Al\({}_{2}\)O\({}_{3}\) in the ash gradually decreased, the difference was not significant.
2. With the increase in the mixing ratio, the condition of wall ash deposition deteriorated gradually, and the average ash deposition rate increased significantly. The average ash deposition rate on the wall was 0.00327 kg/(m\({}^{2}\cdot\)s) without mixing, and the average ash yield was 0.00581 kg/(m\({}^{2}\cdot\)s) when the mixing ratio was 25%, which was 77.6% higher than that without mixing.
3. Reducing the tangential circle diameter can alleviate the ash deposition on the wall. With the decrease in the tangential circle diameter, the ash deposition changed from a zonal distribution to a point-like distribution, and the ash deposition rate and distribution area both decreased significantly. When the tangential circle diameter was reduced to 400 mm, the average ash deposition rate on the wall was reduced to 0.00207 kg/(m\({}^{2}\cdot\)s), which was 37.6% lower than the original condition. However, the influence of reducing the circumferential diameter on the combustion efficiency of the boiler needs to be further evaluated.  
Conceptualization, K.L. and B.W.; methodology, B.W.; formal analysis, J.W.; investigation, F.W.; resources, B.W.; data curation, Y.Q.; writing--original draft preparation, T.L.; writing--review and editing, T.L. and N.L.; visualization, N.C.; funding acquisition, K.L. and B.W. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Major Science and Technology Projects of Xinjiang Uygur Autonomous Region (2024A01005), the National Natural Science Foundation of China (NO. 22178298), the Special Project of the State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources (Grant No. PYKT2024006), the Tianshan Innovation Team Plan of Xinjiang Uygur Autonomous Region (NO. 2023D14010).  
All data is contained within the article.  
Authors [PERSON] and [PERSON] were employed by the company Xinjiang Xinye State-Owned Property Management (Group) Co., Ltd. Author [PERSON] was employed by the company Xinjiang Xinye Science and Technology Innovation Research Institute Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.