EXTRACTING DEVICE FOR FULVIC ACID DISSOLVED IN FRESH WATER BODY AND PREPARATION METHOD THEREFOR

An extracting device for fulvic acid dissolved in a fresh water body. The extracting device comprises a raw water supply unit, a pretreatment unit, a reverse osmosis concentration unit, a pH adjustment unit, a water tank (9), a general control system (5), a filtration and purification unit and a fulvic acid extracting unit. Further disclosed is a method for extracting fulvic acid dissolved in a fresh water body. The method comprises the following steps: separating purified water from concentrated water by means of the reverse osmosis concentration unit, letting the concentrated water enter into the water tank (9) once again for circulation and concentration until the concentration ratio is suitable, and closing the concentrating system; achieving automatic pH adjustment of the water body after concentration by means of the pH adjustment unit, which not only saves labor and reduces production costs, but also has a higher accuracy for the pH adjustment; separating fulvic acid from insoluble impurities by means