Background Titanium was first used in chemical plant in the mid-1960’s. Its outstanding resistance to corrosion in oxidising chloride environments, sea water and other aggressive media were rapidly established. In several processes titanium was the first and only choice for effective plant performance and acceptable levels of life cycle cost.
Performance of Titanium in Various Chemical EnvironmentsToday as shown below titanium is more widely used. Costs of material and fabrication have both stabilised and titanium equipment, properly designed can compete with most of the more common but usually less effective corrosion resistant alloys.
Table 1. Process media where titanium’s oxide film is stable (within operating boundaries).
Environment Performance Chlorine and chlorine compounds a. Moist chlorine gasb. water solutions of chlorites, hypochlorites, perchlorates and chlorine dioxidec. Chlorinated hydrocarbons and oxychloro compounds Other halogens a. Bromine; moist gases, aqueous solutions and compoundsb. Iodine; moist gases and compounds Water a. Fresh water, steamb. River waterc. Seawaterd. Water containing organisms that cause biofoulinge. Water containing micro-organisms that would typically cause microbiologically influenced corrosion in other materials of construction Oxidising mineral acids a. Nitricb. Chromicc. Perchloricd. Hypochlorous (wet chlorine gas) Inorganic salt solutions a. Chlorides of such minerals as sodium, potassium, magnesium, calcium, copper, iron, ammonia, manganese, nickelb. Bromide saltsc. Sulfides, sulfates, carbonates, nitrates, chlorates, hypochlorites Organic acids a. Aceticb. terephthalicc. Adipicd. Citric (aerated)e. Formic (aerated)f. Lacticg. Stearich. Tartarici. Tannic Organic chemicals (with moisture or oxygen) a. Alcoholsb. Aldehydesc. Estersd. Ketonese. Hydrocarbons Gases a. Sulfur dioxideb. Ammoniumc. Carbon dioxided. Carbon monoxidee. Hydrogen sulfidef. Nitrogen Alkaline Media a. Sodium hydroxideb. Potassium hydroxidec. Magnesium hydroxided. Ammonium hydroxide
Fabrication CostsFabrication costs for titanium pressure vessels are surprisingly lower than for some other widely used corrosion resistant alloys.