2 What is Shale gas? And why is it important? Is natural gas trapped within shale formations.And why is it important?Energy dependenceReduce greenhouse gas emissions
3 Purpose Take raw shale gas and purify. Produce compressed natural gas/pipeline gas.Produce liquefied natural gas (LNG)Supply methane for Ammonia Plant, Air Separations and Syngas Plant, the Direct Iron Reduction Plant, and Combined Heat/Power plant.Supply Nitrogen (N2) to Ammonia Plant.Produce natural gas liquids (NGL) for sale.
7 First Step: Water Removal and Condensation Gravity SeparationExample of Horizontal Separator
8 First Step: Water Removal and Condensation Purpose: To separate gas/liquid phases.Additionally water and NGLs may be separated within the same unit given proper settling time.Proper pressure and liquid-level controls required.A mist extractor at gas exit captures droplets too small to settle by gravity.The sudden change in momentum generates the separation of liquid from gas.
10 Second Step: Acid Gas Removal Amine TreatingMost commonly used process for removing sour gas in natural gas purification plantsMost Common Amines UsedMonoethanolamineDiethanolamineMethylethanolamineDiisopropylamine
11 Second Step: Acid Gas Removal Pressure Swing Adsorption (PSA)
12 Second Step: Acid Gas Removal BenfieldProcessThermally regenerated cyclical solvent processUses an activated, inhibited hot potassium carbonate solution to remove CO2, H2S and other acid gas components
13 Second Step: Acid Gas Removal Sulfinol ProcessFor selective absorption of H2S, COS and mercaptans, while co-absorbing only part of the CO2The solvent is composed of Sulfolane, DIPA or MDEA and waterGreat for treating large quantity of gas such as natural gas which are at elevated pressure
15 Second Step: Separation H2S and CO2 Room-Temperature Ionic Liquid (RTILs)An ionic liquid comprising an anion having a carboxylate function and an effective amount of water is used as an adsorbent to selectively complex the CO2 yielding a gaseous stream with a greatly reduced CO2 content.
23 Fifth Step: Nitrogen Removal Methods: Cryogenics, Pressure Swing Adsorption, Membrane separation and lean oil absorption.Cryogenics: The only widely acceptable method on the industrial scale.Costs $ /Mscf for plants handling 75 MMscfdCosts $1.00+/Mscf for plants handling 2 MMscfd or less.Methane and Nitrogen condense at different temperatures -256F and -346F respectively.Membrane Process: No membrane alone has the Nitrogen/Methane separation characteristics.PSA and Lean Oil Absorption: Prohibitively high capital costs and require lower volume flows.
25 Sixth Step: Natural Gas Liquid Recovery Turbo Expander and DemethanizerTurbine through which a high pressure gas is expanded to produce work that is often used to drive a compressorLow-temperature distillation column to separate CH4 and Natural Gas Liquids (NGLs)