A drainable urine pouch includes a discharge portion that is foldable between a discharge position and a closed position. In the based-on-charge mode control, spike timing and spiking amount of an acid liquid are set for each lot of product. The cover flap includes interior pouches or other storage features which may be removable from the fold over cover or flap. The method also includes determining whether the channel interval list further includes a second channel interval that needs to be processed based on at least first linkage information, and if needed, generating a second list of contiguous channels and performing at least second channel measurement to determine a second channel availability for each of the second list of contiguous channels. The wastewater is the flowed into a second microbubble chamber having a plurality of diffusers for injecting microbubbles into the wastewater. The current detection circuit detects a current flowing through the first N-channel FET to output current detection signal Vc.