Gas Quality Measurement Peter Schley marcogaz, Paris 13 September 2007

5. Mai 2015 Seite 2 Gas Quality Measurement  Energy billing (superior calorific value, normal density, gas composition) V p x i H s,n E = V n · H s,n VbVb  Quality control (dewpoint, sulfur, etc.) T V n = V b · U Z

5. Mai 2015 Seite 3 Gas Property Data from Measurement Stations  Gas composition CH 4... C 6 +, N 2, CO 2 Superior calorific value Normal density  Sulfur and sulfur compounds H 2 S, COS, mercaptans Total sulfur  Water dewpoint / Hydrocarbon Dewpoint Process gas chromatograph Sulfur GC Water dewpoint The gas properties of the main natural gas flows are measured continuously, stored on an hourly basis and retrieved monthly.

5. Mai 2015 Seite 4  Analyses up to C 14 (in special cases up to C 40 )  Sulfur compounds  Water dewpoint  Hydrocarbon dewpoint  Other trace components Laboratory Analysis (Gas Quality Competence Centre) Laboratory analyses are made several times a year at entry points and at storage facilities during withdrawal.

5. Mai 2015 Seite 5 Limit Values to G 260 (Germany) - EASEE GAS 12.8 to 15.7 (group H gas) 0.55 to 0.75 Max. ground temperature Dry: 3%; wet: 0.5% 30 mg/m³ 6 mg/m³; 16 mg/m³ (temp) 5 mg/m³; 10 mg/m³ (temp) Not specified EASEE Gas Wobbe index in kWh/m 3 Relative density d Hydrocarbon dewpoint Water dewpoint CO 2 Oxygen (O 2 ) Total sulfur (S) Mercaptans (R-SH) Hydrogen sulfide (H 2 S) Carbon oxysulfide (COS) 13.6 to to °C (1-70 bar) - 8 °C (70 bar) 2.5 mol% 0.01 mol% 30 mg/m³ 6 mg/m³ Total 5 mg/m³ Properties DVGW Code G 260

5. Mai 2015 Seite 6 Future Requirements for Gas Quality Determination (1)  Injection of biogas, liquefied natural gas (LNG), hydrogen (  additional gas constituents)  Growing gas trade leads to stronger variations in gas quality (  gas quality transition zones)

5. Mai 2015 Seite 7 Future Requirements for Gas Quality Determination (2)  Prompt and location-specific determination of gas quality increasingly important  More flexibility required  Computer-assisted simulation tools to trace gas quality (gas quality reconstruction system)  Existing measurement technology to be developed further and optimised in terms of costs

5. Mai 2015 Seite 8 Gas Quality Reconstruction System Being Developed at E.ON Ruhrgas  E.ON Ruhrgas filed an application with PTB (verification authorities) in June 2006 for approval of the system for part of the pipeline network.

5. Mai 2015 Seite 9 Principle of Gas Quality Tracing System Subsequent calculation of  superior calorific value H s  normal density  n  gas composition x i (11 constituents) for delivery stations Input data for calculation  H s,  n, x i at entry points  Volume flow at entry points  Volume flow at exit points  Grid topology  Auxiliary data (pressure,...)

5. Mai 2015 Seite 10  PGC technology  Design to be modified to include additional constituents (inter alia, O2, H2 for biogas)  Outlook: multi-function PGCs for billing and quality control (inter alia, sulfur, hydrocarbon dewpoint)  Correlative measurement systems / sensor measurement systems  Development of simple measurement systems for biogas (e.g. based on infrared technology example: INCA, Union)  Further optimisation of costs Improvement of Measurement Technology

5. Mai 2015 Seite 11 Conclusion / Outlook  Growing natural gas trade and injection of, for example, LNG or biogases lead to stronger gas quality variations in terms of time.  Prompt determination of the relevant gas property data has therefore become increasingly important.  Computer-assisted simulation (gas quality tracing systems) and improved measurement technology will help to meet future requirements.

Thank you for your attention. Gas Quality Centre Accredited calibration laboratory / state-approved test centre