Alarming device and method for detecting bilge water

The invention discloses an alarming device and method for detecting bilge water. The device comprises a detection sensor, a single-chip-microcomputer processing module, a display-alarm-storage module and a control output module, wherein the detection sensor is connected with the single-chip-microcomputer processing module which is connected with the display-alarm-storage module and the control output module. The method comprises the following steps that: the single-chip-microcomputer processing module obtains the change range of an instantaneous-variation maximum value to judge the measured values according to all the previous measured values A1-An of the oil content in sewage from detection of the detection sensor; and then sliding average is carried out on the valid measured values of the oil content in the sewage and the previous n-times measured values, and the obtained result is used as alarming-judgment basis. The alarming device and method disclosed by the invention have the advantages that concentrate