Guided Wave News / By Ryan Lerud

Near-infrared (NIR) technology can overcome the major problems associated with real-time inline monitoring of process hydrocarbon streams. In the case of the Naptha Steam cracker and other olefin units in the Refinery, PIONA (Paraffins, Isoparaffins, Olefins, Napthenes, Aromatics) are important properties. Naphtha feed streams can in principle be measured on-line by GC techniques, but the parameter measurements required for effective control include PIONA and %Distillation curve, which require long elution times and the added cost of a sample conditioning system.

PIONA Petrochemcial (Hydrocarbon) molecules measured by NIR Spectroscopy.

PONA vs PIONA, what’s the difference?

PIONA is a more exact measurement standard. PIONA considers n-paraffins and isoparaffins to be different.  N-paraffins have long straight chains and provide higher cetane values for diesel fuels. The melting point of n-paraffins often occurs between 230-370°C, which results in a worsening of the cold flow properties (cold filter plugging point, pour point) of the diesel fuel. Isoparaffin molecules, such as iso-butane, contain branched side chains. As a result, isoparaffins increase the viscosity, lower pour point, and increase the octane of the fuel. The ratio of n-paraffins to iso-paraffins is an important parameter in some fuel blending operations.