Most liquefied hydrocarbon mixtures are supplied with additional head space pressurization using a high purity inert gas such as helium to prevent the lighter hydrocarbon components from separating after final production. To maintain composition during use, the mixture may supplied in a cylinder using a dual port valve to allow additional pressure to be introduced as required to keep the head space pressure consistent.
As the liquid mixture is consumed, and the cylinder pressure begins to reduce, additional head space helium is introduced to keep conditions constant. To maintain mixture quality, a purity minimum of 5.0 is recommended, with a BASELINE C106 series regulator for pressure control. The outlet pressure of the helium is set to the supplied head space pressure. Mixture pressure control requirements will vary based on mixture properties.
In addition to hydrocarbon blends, dual port valves may be supplied on cylinders used with liquefied products such as Carbon Dioxide, 1,3 Butadiene, Propane, or various refrigerants. They allow the product to be used in either liquid phase with the withdrawal tube, or through the vapour port. For vapour withdrawal, our BASELINE C106 series regulator is recommended.