DCS-controlled bio-based isocyanate product rectification device and method

The invention relates to a DCS-controlled bio-based isocyanate product rectification device and method. The DCS-controlled bio-based isocyanate product rectification device is characterized by comprising an isocyanate crude product storage tank, a rectification tower, a tower top condenser, a tower top gas-liquid separation tank, a heater and a rectified product storage tank, dCS control points are respectively arranged between the rectifying tower and the isocyanate crude product storage tank, between the rectifying tower and the rectified product storage tank, between the steam heating system and the heater, between the circulating cooling water system and the tower top condenser, between the tower top gas-liquid separation tank and the gas phase outlet, and between the rectified product storage tank and the product packaging line. While renewable biomass resources are used for replacing traditional petrochemical products, green chemical production is combined with refined and DCS operation processes, manua