# 3D Printed Microfluid Separators for Solid/Liquid Suspensions
## 3 Results and Discussion
### Separation Efficiency
These secondary flows can significantly influence the overall fluid dynamics, potentially affecting separation processes within the channel. The results show that efficiency diminishes significantly at higher flow rates, which can be due to the increased turbulence, causing enhanced mixing. The SLA 2 separator achieves moderate separation at 200 mL min\({}^{-1}\) with a \(\Delta\) of 0.0557. As the flow rate increases, the efficiency drops, with very low \(\Delta\) values at 250 mL min\({}^{-1}\) and 300 mL min\({}^{-1}\). The FFF separator demonstrates minimal separation efficiency across all flow rates, with \(\Delta\) values close to zero. The most notable difference occurs at 250 mL min\({}^{-1}\) with a \(\Delta\) of 0.0472, but overall separation performance remains low. The best overall performance is notable for the SLA 1 separator at a flow rate of 200 mL min\({}^{-1}\). For calcium carbonate (Table 3), the SLA 1 separator demonstrates its highest separation efficiency at 200 mL min\({}^{-1}\) with a \(\Delta\) of 0.0895. The efficiency slightly decreases as the flow rate increases to 250 mL min\({}^{-1}\) and significantly drops at 300 mL min\({}^{-1}\), indicating that lower flow rates are more effective for this separator. The SLA 2 separator shows a relatively consistent separation efficiency across the different flow rates. The \(\Delta\) values at 200 mL min\({}^{-1}\) and 250 mL min\({}^{-1}\) are similar, while the highest efficiency is observed at 300 mL min\({}^{-1}\) with a \(\Delta\) of 0.0883. This suggests that the SLA 2 separator has optimal efficiency at the highest tested flow rate. The FFF separator exhibits a moderate separation efficiency at all tested flow rates, with the highest \(\Delta\) of 0.0719 occurring at 250 mL min\({}^{-1}\). The efficiency decreases slightly at 200 mL min\({}^{-1}\) and 300 mL min\({}^{-1}\). The best overall performance is once again notable for the SLA 1 separator, at a flow rate of 200 mL min\({}^{-1}\), probably due to the increased turbulence at higher flow rates, which causes mixing. For quartz sand (Table 4), the SLA 1 separator shows that the separation efficiency is highest at a flow rate of 200 mL min\({}^{-1}\) with a \(\Delta\) of 0.1255. At a higher flow rate of 300 mL min\({}^{-1}\), the efficiency drops significantly to a \(\Delta\) of 0.0666, suggesting that this separator performs better at lower flow rates. Data for the 250 mL min\({}^{-1}\) flow rate are unavailable due to the constant clogging of the separator channels. These data emphasize the realistic problems in the application of such microsystems, which is of great importance. The SLA 2 separator demonstrates its highest separation efficiency at the highest tested flow rate of 300 mL min\({}^{-1}\), with a \(\Delta\) of 0.1767. This indicates that this separator is most effective at separating powder at higher flow rates. The FFF separator shows the highest separation efficiency at the lowest flow rate of 200 mL min\({}^{-1}\) with a \(\Delta\) of 0.2263. As the flow rate increases to 250 mL min\({}^{-1}\) and 300 mL min\({}^{-1}\), the efficiency drops significantly, with \(\Delta\) values of 0.0523 and 0.0537. This suggests that the FFF separator is most effective at lower flow rates and less effective as the flow rate increases. The best overall performance is notable for the FFF separator at a flow rate of 200 mL min\({}^{-1}\), probably due to the increased turbulence at higher flow rates, which causes mixing. The FFF separator might be a better option for this suspension due to the different channel roughness caused by the manufacturing.