Water quality detection method and system in sewage treatment process

The invention relates to a water quality detection method and system in a sewage treatment process. The method comprises the following steps: detecting a water sample to be detected by adopting an ion detection sensor; judging whether a time node of the chemical detection period is reached or not; if yes, conveying the to-be-detected water sample into a chemical detection instrument for detection, comparing detection results of the chemical detection instrument and the ion detection sensor, and if a difference value between an ion detection value of the ion detection sensor and a chemical detection value of the chemical detection instrument exceeds a set allowable range, calibrating the ion detection sensor; otherwise, taking an ion detection value of the ion detection sensor as a water quality detection result; inputting a detection result of the ion detection sensor into the error compensation model to obtain a calibration value; and superposing an ion detection value of the ion detection sensor and the cal