Safe Handling and Storage of Ethylene oxide: Properties of Ethylene oxide are: Colourless gas, mp – 111.3 degree C, bp 10.7 degree C, LEL 3%, UEL 100%, fp – 17.8 degree C. It is toxic, flammable and explosive, Fire & explosion hazard when exposed to heat or flame, To fight fire use Co2, DCP. It can react with acids and bases, alcohol, ammonia, copper, mercaptans, potassium, tin chlorides etc. Vaporises rapidly at ambient temperature, can cause cold burns and it is soluble in water.
PVC gloves, aprons, gum boots, goggles or face shield and breathing apparatus are necessary equipment to handle EO.
Safety Measures: Avoid heat, flame and ignition sources. Dilute spillage with plenty of water. Provide N2 blanking and preferably keep storage tank refrigerated. Its pressure should be kept within operating limits. Equipment cleaning may be done by citric acid. Prevent backflow of any chemical into the EO vessel.
Storage tank should be separated at least 15 mtr from plants and building. Collusion of vehicles should be prevented by fencing and barricade. Spillage should be directed to a remote catch pit by an impermeable and sloppy floor.
It polymerises by iron rust, acids, bases and by chlorides of iron and other metals. Polymerisation is highly exothermic and may result in explosion.
Material of construction – stainless steel or MS aluminised from interior. Insulation – mineral wool covered by galvanised or SS cladding.
Level gauges are float differential pressure type torque tube type or magnetic float type. Compound pressure and vacuum gauge is preferable. Temperature gauge with high and low temperature alarm necessary. Double safety valves (at least one must be locked open) with 2 mtr discharge outlet pipe, flame arrester on outlets and N2 purging connections are required. Lines should not be of less than 1 inch diameter. To prevent reverse flow of EO, NRV and double block and bleed valve system is required.