Anaerobic digestion tank adjusting system with detection function and adjusting method

An anaerobic digestion tank adjusting system with a detection function comprises a material receiving barrel, a sampling barrel, at least one acid/alkali solution adding barrel, at least one trace element solution adding barrel and a PLC (programmable logic controller) electric control cabinet which are arranged outside a fermentation tank, a sampling opening is formed in the fermentation tank and communicated to the material receiving barrel or the sampling barrel through a sampling connecting pipe, and the sampling connecting pipe is connected with the PLC electric control cabinet. A pH electrode and an ORP electrode are arranged in the sampling barrel, the pH electrode and the ORP electrode automatically detect the pH value and the ORP value of a sample and then transmit the pH value and the ORP value to the PLC electric control cabinet, the acid/alkali solution adding barrels and the trace element solution adding barrels are respectively connected with metering pumps, and the metering pumps are respective