Prevention of Corrosion by Inorganic Zinc Coating on Petroleum Product Carrier

Abstract

There are many comparatively small oil tankers carrying clean products of petroleum or petrochemicals. Recently, the sizes of these product carriers are being apt to become larger type due to the need in the world wide petroleum situation.
Internal tank surfaces of this carriers are exposed to severe corrosive environment such as high solubility Hydrocarbons, rolling and moving ballast water, high temperature condition of Butterworth cleaning and corrosive moisture contaning active sulfur compound.
Pitting or local corrosion may occur attacking on unprotected internal tank structure and corrosion products often causing cargo contamination and pump trouble.
Method for preventing these corrosion is very difficult and expensive, cathodic protection, use of organic inhibitor in cargo or water, clud of stainless steel or lining of Fiber Reinforced plastics etc. are not so perfect every time and difficult to apply. Protective coating of Inorganic Zinc Silicate is comparatively economical and considered to be endurable against clean cargoes and seawater ballast.
We hereby report the results investigated on the durability of Inorganic Zinc coating to clean products and contamination of cargoes.