Seawater dissolved organic matter separation and enrichment method

The invention relates to a seawater dissolved organic matter separation and enrichment method, and belongs to the technical field of seawater separation and enrichment. The method comprises the following steps: building a seawater separation and enrichment system on a ship according to the condition of a required sample, wherein the seawater separation and enrichment system comprises an extraction pump, multiple stages of tangential ultrafiltration devices connected in series, booster pumps arranged between every two adjacent stages of tangential ultrafiltration devices, and sample collection boxes arranged stage by stage; extending a water inlet pipe of the extraction pump into seawater to be separated, opening the extraction pump and a booster pump to pump the seawater to be separated into each stage of tangential ultrafiltration device, and enabling the flow velocity of a backflow component of each stage of tangential ultrafiltration device to be 10-20 times of the flow velocity of a permeation component;