CROSS-FLOW FILTRATION DEVICE AND CROSS-FLOW FILTRATION METHOD

A cross-flow filtration device includes: a filter module which includes an inner chamber and an outer chamber separated by a semipermeable membrane; a process liquid tank which is configured to accommodate a process liquid; a pump which is configured to cause the process liquid to circulate to the inner chamber in the filter module and the process liquid tank; a replenisher tank which is configured to accommodate a replenisher liquid to be replenished into the process liquid tank, at least one or more sensors which are configured to measure a pressure of the circulating process liquid; and a replenisher measurement unit which is configured to measure an amount of the replenisher liquid supplied from the replenisher tank to the process liquid tank. The process liquid tank is configured to be continuously replenished with the replenisher liquid.