BS EN ISO 16903:2015 pdf free

BS EN ISO 16903:2015 pdf free.Petroleum and natural gas industries
It is recommended that all personnel concerned with the handling of LNG should be familiar with both the characteristics of the liquid and the gas produced.
The potential hazard in handling LNG stems mainly from three important properties.
a) It is extremely cold. At atmospheric pressure, depending upon composition, LNG boils at about -160 °C. At this temperature, the vapour is denser than ambient air.
b) Very small quantities of liquid are converted into large volumes of gas. One volume of LNG produces approximately 600 volumes of gas.
c) Natural gas, similar to other gaseous hydrocarbons, is flammable. At ambient conditions, the flammable mixture range with air is from approximately 5 % to 15 % gas by volume. If vapour accumulates in a confined space, ignition can result in detonation and shock wave overpressure.
This International Standard focuses on LNG, its properties, and resultant hazards. When evaluating the hazards at an LNG site, designers need to consider all systems present. Often, the LNG itself does not present the greatest hazard; other systems such as LPG-based refrigeration at the liquefaction plant or high pressure gas send out at a regasification plant can dominate the overall site risk profile.
LNG is a mixture of hydrocarbons composed predominantly of methane and which can contain minor quantities of ethane, propane, butane, nitrogen, or other components, normally found in natural gas.
The physical and thermodynamic properties of methane and other components of natural gas can be found in reference books (see Annex A) and thermodynamic calculation codes. Although the major constituent of LNG is methane, it should not be assumed that LNG is pure methane for the purpose of estimating its behaviour. When analysing the composition of LNG, special care should be taken to obtain representative samples not causing false analysis results due to distillation effects. The most common method is to analyse a small stream of continuously evaporated product using a specific LNG sampling device that is designed to provide a representative gas sample of liquid without fractionation. Another method is to take a sample from the outlet of the main product vaporizers. This sample can then be analysed by normal gas chromatographic methods, such as those described in ISO 6568 or ISO 6974.BS EN ISO 16903 pdf download.