Natural Gas
Authors: Hammer Georg , Lübcke Torsten , Kettner Roland , Pillarella Mark R. , Recknagel Herta , Commichau Axel , Neumann Hans‐Joachim , Paczynska‐Lahme Barbara 
Published: September 2006

AbstractThe article contains sections titled:1.Introduction1.1.Composition1.2.Physical Properties1.3.Combustion Properties1.3.1.Calorific Value1.3.2.Wobbe Index2.Treating2.1.Objectives of Natural Gas Treating2.2.Natural Gas Wells and Field Installations2.3.Processing Steps During Production2.3.1.Use of Sulfur Solvents2.3.2.Removal of Mercury2.3.3.Dehydration2.3.4.Removal of Hydrocarbons2.4.Removal of Carbon Dioxide and Sulfur Components2.4.1.Absorption Processes2.4.1.1.Physical Absorption Process2.4.1.2.Chemical Absorption Processes2.4.1.3.Physical ‐ Chemical Absorption Processes2.4.2.Liquid Oxidation Processes2.4.3.Adsorption Processes2.4.3.1.Adsorption of Carbon Dioxide2.4.3.2.Adsorption of Hydrogen Sulfide2.5.Membrane Processes2.6.Cryogenic Natural Gas Separation2.7.Recovery of Sulfur2.7.1.Claus Process2.7.2.Tail‐Gas Cleanup Processes2.7.3.Incineration2.8.Example of an Integrated Plant3.Liquefaction3.1.Physical Properties of LNG3.2.History3.3.Production3.3.1.Baseload Liquefaction Processes3.3.2.Peak‐Shaving Liquefaction Processes3.4.Storage3.5.Transportation3.5.1.Peak Shaving3.5.2.Baseload3.6.Safety Aspects4.Transmission, Storage, and Distribution4.1.Transportation4.1.1.Pipeline Transmission4.1.2.LNG Transportation4.1.3.Gas Transmission Pipeline Design4.1.4.Increase in Capacity4.1.5.Transient Flow in Gas Transmission Systems4.2.Storage4.2.1.Determination of Storage Requirements4.2.2.Storage Systems4.2.3.Optimized Storage Planning4.3.Distribution5.Economic Aspects6.Testing and Analysis6.1.Analysis of Natural Gas Composition6.1.1.Sampling6.1.2.Gas Chromatography6.1.3.Analysis of Nonhydrocarbons6.2.Determination of Physical Properties6.2.1.Density6.2.2.Calorific Value6.2.3.Molecular Mass6.2.4.Dew Point7.AcknowledgementNatural gas is a mixture of gaseous hydrocarbons with impurities mainly made of nonhydrocarbons. It occurs in subsurface deposits of many geologic formations. Natural gas is recovered with wells that are drilled into these deposits and is produced at the well site in compositions of considerable variety. The most important method for chemical analysis of natural gas is gas chromatography. TheWobbe indexis the most important physical characteristic for the classification of natural gases. Natural gas is primarily employed as clean heating fuel in industry, power plants, commercial installations, and households. The objectives of natural gas treating are the adjustment to the required quality standards and the recovery of byproducts. Removal of the sour gas components hydrogen sulfide and carbon dioxide is one of the most common aims of natural gas treating. Of the gas traded across international borders, 75 % is shipped by pipelines, and 25 % is carried by liquified natural gas tankers. A large share of internationally traded natural gas is normally sold by producers under long‐term contracts of up to 35 years' duration in order to compensate for the heavy front‐end investment in production, purification, and transportation facilities.