The invention belongs to the field of
water pollution monitoring, and particularly relates to an online measurement method for
petroleum in water, which comprises the following steps: step 1,
water sampling: a trigger unit transmits the detected
fluorescence intensity of the water surface to a
control unit, and the
control unit controls the
water sampling frequency of a sampling pump in the
water sampling unit according to the
fluorescence intensity detected by the trigger unit; step 2, extraction: sending the
water sample extracted by the sampling pump into a sample storage container, and extracting oil substances into an extraction
reagent; step 3, separation: conveying into a separation container through a conveying pump; and 4, measuring, namely feeding the extraction
reagent into a
cuvette of a measuring unit for measuring the content of the oil substances. According to the design, a method of combining water surface early warning measurement and
underwater quantitative measurement is adopted,
pollution occurrence can be judged in time, and the content of
underwater oil substances can be measured online, so that
pollution sources can be conveniently fed back and controlled in time, and the timeliness of online
water environment monitoring is guaranteed.