Efficiently effectively inserting inert gases into the entire volumes and ullage spaces of ships' steel ballast tanks to retard interior corrosion

摘要

A (1) piping grid, nozzles and/or deflectors and/or diffusers placed on the piping at a certain intervals, and (2) header pipes connecting the piping grid to (3) an inert gas generator via (4) a compressor and (5) an optional cooler support efficient and effective injection of inert gases into all regions and volume of ships' steel ballast tanks, retarding or avoiding corrosion. Efficiency in use of generated inert gas, effective entrance of inert gas into ballast tank spaces that may be remote and/or difficult of access, and minimization of the elapsed time to fill the tank with inert gas while discharging essentially all oxygen-containing air previously within the tank, are all realized by progressive, staged, insertion of cooled inert gases from tank bottom to tank top, marshaling contained air and expelling it out the tank tops.

主权项

1. A method of retarding such corrosion as would normally occur in air of the interior of a ship's steel ballast tank of complex geometry, the method comprising:
entering a mixture of gases depleted in oxygen into the ship's ballast tank from a multiplicity of gas emission points at a corresponding multiplicity of locations selected in respect of the complex geometry of the tank so as to, insofar as is possible, “coral” existing atmospheric air within the tank, and force this air from the bottom and from the farthest lateral regions of the tank onwards and upwards to ejection from vents at the top of the ballast tank; wherein by strategic selection of the multiplicity of locations less of the gaseous mixture is used to develop an inerted condition inside the tank than would be the case if the gaseous mixture was simply pumped into the tank at one or at two tank bottom locations; wherein by strategic selection of the multiplicity of locations less of the gaseous mixture is used to faster develop an inerted condition inside the tank than would be the case if the gaseous mixture was simply pumped into the tank at one or at two tank bottom locations; wherein by strategic selection of the multiplicity of locations less of the gaseous mixture there are a reduced number, or no, isolated regional volumes within the tank that still contain air as would be the case if the gaseous mixture was simply pumped into the tank at one or at two tank bottom locations; wherein the gaseous mixture entered into the ballast tank retards such corrosion as would normally occur in air throughout the entire interior of the tank without significant omitted volumes or “hot spots” nonetheless that this gaseous mixture is judiciously entered in minimal effective quantity; wherein the entering provides (1) better coverage of the tank interior volume with (2) less wastage of gaseous mixture out the vents than would alternatively be the case if the gaseous mixture was simply pumped into the tank at one or at two tank bottom locations.