Table 5. Observations During 11 h of Semicontinuous Operation of the CFD25; Includes the Time of Occurrence, Number of Cakes Where the Issue Was Observed, and Solutions to the Challenges.

observation during semicontinuous run	solution(s)
filtration (port 1, 2, and 3) did not halt at dry land due to slurry splashes on the walls of the tube. This resulted in non-consistent deliquoring in port 4	splashes on the tube walls may cause the camera to briefly detect the splashes as a light-to-dark transition, therefore incorrectly measuring this splash as the liquid level
	to prevent this, if the liquid level detected by the camera momentarily jumps to another position, the software will ignore this and continue to measure the true liquid level
note: in cases where filtration and/or washing is protracted, the process was set to stop after a defined period and index to the next stage regardless of the residual solvent volume left behind, as described in Section 2.4.3.1	other vision system software improvements will be made to increase robustness of dryland detection, e.g., viewing windows and time windows will be adjusted to improve reliability
blockage of filter plate, resulting in liquid volume not being fully drawn through the cake. This resulted in the cake being indexed to the next stage with a larger quantity of solvent on top of the cake than desired	the filter plate in port 1 will contain the most fines, and therefore most likely be the first filter plate to blind. A “back pulse” feature will be added to port 1 where a back pulse of compressed air will be applied to the filter plate before each aliquot of slurry is dispensed, helping to clear fines from the filter plate therefore improving filtration performance
	improvement to WIP sequence. For example, WIP sequence will now include a “contact time” to allow more time for WIP solvent to dissolve material within the filter plate before being drawn through the filter plate
drops of solvent falling into the tube, resulting in disturbance of meniscus, leading to loss of liquid level detection	reduction of solvent dropping from the atomizer by reversing the pump after dispensing
	a “drip-check” feature will be added to the software to ignore any disruption to the meniscus