The invention relates to a method and a
system for monitoring
total phosphorus and
total nitrogen of
water quality on line. The monitoring method comprises the following steps of: a, acquiring a
water sample; b, performing
ultraviolet digestion on the acquired
water sample according to the principle of
ultraviolet digestion and
ultraviolet absorption methods; and c, discharging the digested
water sample into a
cuvette to perform
ultraviolet absorption through
ultraviolet light, and meanwhile calculating
light intensity through a
light sensitive sensor to obtain the concentration of pollutants. The detection
system comprises a PLC, a CPU, a sample pretreatment device, a multi-way
sampling valve, an
injector, a reactor, a
detector, a human-computer interface and a
communication interface, wherein the sample pretreatment device, the
injector, the reactor and the
detector are connected to the multi-way
sampling valve through pipelines respectively. The method and the
system can efficiently, quickly, stably and accurately perform continuous detection, storage and forwarding on the concentrations of the
total phosphorus and the
total nitrogen, and have the advantages of high
measurement precision, stable performance, high efficiency, small volume, light weight, convenient
assembly and debugging, low cost, low
energy consumption, independent use, long-term continuous work and the like.