CORROSION PREVENTING METHOD AND DEVICE FOR STAINLESS STEEL CARGO TANK OF LIQUID CARGO TRANSPORTATION SHIP

摘要

PURPOSE: To provide a method and a device for restricting corrosion of stainless steel in contact with a gas phase part above a liquid face in a stainless steel cargo tank of a liquid cargo transportation ship for transporting liquid crude phosphoric acid. CONSTITUTION: This device comprises a gas intake part and a gas discharge part. The gas intake part comprises a blower arranged on an upper deck, a main an air duct, branch air ducts communicating with the main duct and the gas phase part above the liquid level in the cargo tank, equipped with one or more valves therein. The gas discharge part comprises an access hatch arranged to communicate with the gas phase part above the liquid level in the tank, a vent branch pipe communicating with the access hatch, and a vent post comprising a control outlet, a control inlet and a gas free cover at an upper end.