Fast Analysis of Extended Natural Gas using the New Transportable INFICON Micro GC Fusion Debbie Hutt PITTCON 2013 Philadelphia, Pa Wednesday March 20th, 2012
Cologne, Germany Shanghai, China 325 employees Syracuse, NY, USA 394 employees 180 employees Balzers, Liechtenstein World wide, publically traded company with offices in 14 countries 900 employees Over 20 years of experience with designing and manufacturing GC and GC/MS instrumentation 2
3 Outline Natural gas application information The Micro GC Fusion for natural gas analysis Industry standard information Future application development
Natural Gas Application Information Natural gas composition analysis is critical for : Producers Gatherers Gas distribution companies Gas utility companies Gas engine and appliance manufacturers Independent testing laboratories Natural gas contains a large percentage of methane (CH 4 ), and smaller amounts of fixed gases, and light hydrocarbons Often, it is desirable to analyze C 6 to C 12 components in order to obtain more information about the gas sample Liquefied petroleum or liquid propane (LP) gas and butane/air mixes can be run using the same method as natural gas 4
5 Natural Gas Analysis Scenarios Scenario 1 Wellhead analysis Gas and electricity supplied externally via a truck Wide BTU range gas Scenario 2 Gas appliance or engine development Gas and electricity supplied in a laboratory Natural gas, LPG, butane/air mixes Scenario 3 Gas utility company - leak detection Gas and electricity supplied in a laboratory Natural gas, landfill gas, transformer fault, cable burn
6 Natural Gas Physical Properties Due to variations in natural gas composition, it is important to measure physical properties, especially for custody transfer situations A small change in value can have a significant financial impact Physical properties of interest include: Heating Value (BTU/ft 3 ) Relative Density/Specific Gravity The amount of heat released during the combustion of a specified amount of a substance The ratio of the density of a substance to the density of water
7 Typical Natural Gas Composition Component Heating Value (BTU/ft 3 ) Wellhead % City gas (pipeline) % Nitrogen (N 2 ) 0 <10 < 2 CO 2 0 <10 < 1-2 Methane (C 1 ) 1010 70-90 93-96 Ethane (C 2 ) 1770 <10 < 1 Propane (C 3 ) 2516 <10 < 0.5 Isobutane (C 4 ) 3252 <2 < 0.5 n-butane (C 4 ) 3262 <2 < 0.5 Isopentane (C 5 ) 4001 <2 < 0.5 n-pentane (C 5 ) 4009 <2 < 0.5 Hexanes Plus (C 6 +) 5126 <2 < 0.2
8 Micro GC Fusion Configuration and Method Configuration Column stationary phases 15 m RT-Q-BOND, 15 m Rxi-1 Injectors Variable volume Detector MEMS TCD Carrier gas pressure 50 psi Carrier gas consumption 0.5 to 1.5 ml/min per channel Dynamic Range 10 6 Method RT-Q-BOND temperature ramp Rxi-1 temperature ramp Injector temperature Column head pressure 80 C (10s hold, 0.35 C/s) 150 C 80 C (90s hold, 1.7 C/s) 250 C 90 C 30 psi Objective: Elute C4 to C12 hydrocarbons on the Rxi-1 column in under 3 minutes
Temperature Programming Preliminary Fusion data was acquired on: 15 m RT-Q-BOND for N 2, CO 2, C1-C4 components 15 m Rxi-1 column for C4 to C8 components Extended component analysis allows for more accurate heating value and other physical property calculations 9
10 Effect of C6-C12 on Heating Value Compound Heating Value (BTU/Ft 3 ) Gas 1 Mol% Gas 2 Mol % N 2 0 1.525 1.515 CO 2 0 1.206 1.199 Methane 1010 88.67 89.12 Ethane 1770 2.994 3.048 Propane 2516 2.006 2.020 isobutane 3252 1.004 1.000 n-butane 3262 0.996 0.999 isopentane 4001 0.300 0.300 n-pentane 4009 0.300 0.300 n-c6 4756 0.603 0.293 n-c7 5503 0.320 0.167 n-c8 6249 0.056 0.028 n-c9 6996 0.019 0.007 n-c10 7742 0.003 0.001 n-c11 8489 0.0003 (3 ppm) 0.0001 (1 ppm) n-c12 9236 0.00009 (0.9 ppm) 0.00004 (0.4 ppm) Total Mol% 100 100 Heating Value (Ideal) - 14.696 psi, 60 C 1140 BTU/ft 3 1120 BTU/ft 3 Heating Value (Real) - 14.696 psi, 60 C 1143 BTU/ft 3 1123 BTU/ft 3
N2 11 ethane n-butane isobutane n-pentane isopentane propane isobutane n-butane Micro GC Fusion Natural Gas 2-Channel CO 2 methane 15 m RT-Q-BOND 80 C (10s hold, 0.35 C/s) 150 C 15 m Rxi-1 80 C (90s hold, 1.7 C/s) 250 C C6s C7s C8s
12 Extended Natural Gas Analysis The Rxi-1 Channel can be used to analyze an extended range of hydrocarbons C6s C7s C8s
13 Isothermal vs. Temperature Programming Isothermal run C4 and C5 hydrocarbons elute late on the RT-Q- BOND Potential for carry over Extended run times Allow 2-4 minutes to clear the column Temperature programmed run C4 and C5 hydrocarbons elute earlier on the RT-Q- BOND C6-C8 compounds elute earlier on the Rxi-1 Ensures a clean column Minimizes time between runs Example: Rxi-1 Component 120 C Isothermal RT (s) Temperature Programming RT (s) nc6 77 69 nc7 116 85 nc8 N/A 110
14 Cycle Time With temperature programming, the columns must be heated and cooled quickly The Micro GC Fusion cycle time is minimized so that more samples can be run in a timely fashion
Industry Standard GC Methods for Natural Gas Gas Processors Association (GPA) 2145-09 Gas Processors Association (GPA) 2261 Gas Processors Association (GPA) 2172 Gas Processors Association (GPA) 2286 (Extended) Gas Processors Association (GPA) TP-17 American Society of Testing and Materials (ASTM) D3588 International Standards Organization (ISO) 6976 Repeatability (r) Difference in measurement for repeat analysis of same sample on same instrument (same method) by same operator Used to check the instrument Measure of precision 15
16 Natural Gas GPA 2261 Repeatability Component GPA 2261 Repeatability (r) +/- % Nitrogen (N 2 ) 2 CO 2 3 Methane (C 1 ) 0.2 Ethane (C 2 ) 1 Propane (C 3 ) 1 Isobutane (C 4 ) 2 n-butane (C 4 ) 2 Isopentane (C 5 ) 3 n-pentane (C 5 ) 3 Hexanes Plus (C 6 +) 10 Example: Component Value (%) r range (%) Nitrogen 2.485 2.435-2.535 Methane 89.468 89.23 89.65
17 Future Application Development Optimize natural gas analysis to analyze up to C12 Rxi-1 column length Shorten column from 15 m to 5 or 10 m to increase run speed and improve peak shape Rxi-1 column film thickness Reduce film thickness from 2 µm to 1.2 µm Fixed volume injector to minimize matrix effects Industry standard repeatability testing Integrated sample conditioning Heated regulator (100-110 C) Pressure reducer
18 Visit booth #1015 or Visit our website www.inficon.com for more information
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