Online automatic detection device for arsenic in water environment and detection method thereof

The invention discloses an on-line automatic detection device for arsenic in a water environment and a detection method thereof. The on-line automatic detection device comprises a power source, a metering module, a multi-way drain valve, an expelling module, an absorption detection module and a three-way closed valve, one end of the metering module is communicated with a power source, the other end of the metering module is communicated with a material port of the multi-way discharge valve, a first output end of the multi-way discharge valve and a second output end of the multi-way discharge valve are respectively communicated with the material port through electromagnetic valves, the first output end of the multi-way discharge valve is communicated with a first branch pipe, and the second output end of the multi-way discharge valve is communicated with a second branch pipe; the second output end of the multi-way discharge valve communicates with a second branch pipe, and the output end of the first branch pi