## 6 Conclusions  
In this paper, a pressure filtration calculation model for mud slurry after flocculation consolidation was established based on the one-dimensional large strain consolidation theory and was verified with the help of a laboratory pressure filtration model test. The pressure filtration parameters were extended on an engineering scale to further analyze the influence of the pressure filtration parameters on the compression deformation of a mud cake, and the recommended values of the filtration parameters for practical application were given. The main conclusions are as follows.  
1. The mud cake thickness after pressure filtration obtained by the calculation model proposed in this paper combined with the one-dimensional large-strain consolidation theory is only slightly larger than the measured mud cake thickness, and the trend of the mud cake thickness against the dewatering time is basically the same. It is feasible to use the calculation model proposed in this paper to analyze the relationship between mud cake deformation and dewatering time.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Initial Thickness (mm)**} & \multicolumn{6}{c}{**Filtration Pressure (MPa)**} \\ \cline{2-7}  & **0.4** & **0.6** & **0.8** & **1.0** & **1.2** & **1.4** \\ \hline
180 & 8.61 & 12.14 & 15.10 & 17.28 & 18.23 & 19.30 \\
240 & 6.40 & 9.61 & 12.05 & 14.12 & 15.09 & 16.29 \\
300 & - & 7.73 & 10.06 & 11.56 & 12.84 & 13.73 \\
360 & - & 6.71 & 8.77 & 9.97 & 11.07 & 11.98 \\
420 & - & 5.91 & 7.51 & 8.88 & 9.89 & 10.82 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Treatment efficiency v at different initial cake thicknesses and filtration pressures.  
2. An increased initial cake thickness greatly affects the pressure filtration efficiency. In order to achieve the same dewatering effect, doubling the initial cake thickness will lead to an increase several times over in the dewatering time. Reducing the initial cake thickness within a certain range can improve the pressure filtration efficiency.
3. An increased filtration pressure increases the final compression deformation of the mud cake. In order to treat the mud cake to the same water content, an increase in pressure when the filtration pressure is small effectively reduces the dewatering time, but a continuous increase in the filtration pressure after the pressure has been increased to the critical value had less effect on the dewatering time.
4. Considering the processing efficiency and energy consumption, the initial mud cake thickness of 240 mm, filtration pressure of 1.0 MPa, and dewatering time of 30 min obtained from the calculation model in this paper are recommended for slurry treatment.  
Although this study provides a comprehensive study on the factors affecting the performance of mud treatment using the PF-FSCM, there still are some limitations in this paper, such as a single slurry type and no consideration of mud viscosity, which need to be further investigated to improve the applicability of the PF-FSCM to practical engineering.  
Conceptualization, C.H., H.X. and B.B.; methodology, D.L., Y.H. and R.Z.; software, D.L. and Y.H.; investigation, H.X., B.B. and Y.H.; data curation, C.H., H.X., B.B. and D.L.; writing--original draft preparation, C.H. and D.L.; writing--review and editing, C.H., D.L. and R.Z.; visualization, D.L.; supervision, C.H. and D.L.; project administration, C.H. and R.Z.; funding acquisition, R.Z. All authors have read and agreed to the published version of the manuscript.  
This work was funded by the Science and Technology Project of State Grid Jiangsu Electric Power Co., Ltd. (grant NO. J201047).  
Not applicable.  
Authors [PERSON], [PERSON], [PERSON] were employed by the company State Grid Jiangsu Electric Power Co., Ltd. Construction Branch, Nanjing 210000, China.