LPG ACCOUNTING SPECIFICITY DURING ITS STORAGE AND TRANSPORTATION

Criminal activities in a country’s fuel sector adversely affect the country’s sustainable development. To prevent excise tax evasion during petroleum product storage and transportation various methods are used. The most effective methodology is the control of all supply chain and automation of such control. LPG is quite specific product for storage and transportation due to its two-phase composition that continuously changes parameters during storage and transportation. 

In the article, there are considered the problems of measuring LPG volume in a tank and estimation of the error‘s margins. Assessing  the  row of  the errors  that impact the volume calculation  is described. They  include  the reservoir graduation error,  the level measurement error, the temperature measuring error and have to be reduced to the standard conditions (temperature 15 °C) while computing  the  real quantity of LPG.  Incorrect data about LPG  liquid/vapor phase composition can occur  if operator uses only passport data from the last consignment. Redistribution of the component composition occurs every time when the product’s temperature/pressure/quantity in the tank changes. The example of the change of the LPG phasic composition during the process of filling  the  tank  is  also  considered  and  the  related  calculation  errors  are  defined. The  density  calculation  error,  connected with volume  calculation,  is presented as a  function of molar  fraction of propane, mixture  temperature and errors  in composition and temperature. 

It’s concluded  that  the use of accounting  in mass units and volume units should be held together regardless of  the phase state and composition of the LPG.