Recess plate and method for detecting membrane leakage

A method for detecting a membrane leakage in a membrane filter device,

• wherein a membrane filter device includes a stack of adjacent essentially identical recess plates,
• wherein the adjacent recess plates include recesses and the recesses form filter chambers between the adjacent recess plates of the stack,
• wherein a suspension is supplied into the filter chambers on a cake side of a filter cloth,
• wherein the suspension permeates the filter cloth to a filtrate side of the filter cloth, so that a solid content of the suspension deposits on the filter cloth as a filter cake,
• wherein each filter chamber includes a movable membrane,
• wherein the membrane and the recess plate enclose a squeezing chamber,
• wherein the recess plate includes an inlet duct for introducing a pressurizing medium into the squeezing chamber for pressing respective filter cake out mechanically, the method comprising the steps:
• for each of the filter chambers supplying the pressurizing medium into the respective squeezing chamber;
• after supplying the pressurizing medium closing the respective inlet duct tight, monitoring a pressure inside the squeezing chamber;
• and
• detecting a decrease in the pressure as evidence for a leakage of the membrane.