Gas Quality MeasurementPeter Schley

marcogaz, Paris13 September 2007

Seite 218. April 2023

Gas Quality Measurement

Energy billing(superior calorific value, normal

density, gas composition)

V

p

xi

Hs,nE = Vn · Hs,n

Vb

Quality control(dewpoint, sulfur, etc.)

T

Vn = Vb · UZ

Seite 318. April 2023

Gas Property Data from Measurement Stations

Gas composition

CH4 ... C6+, N2, CO2

Superior calorific value

Normal density

Sulfur and sulfur compounds

H2S, 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.

Seite 418. April 2023

Analyses up to C14

(in special cases up to C40)

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.

Seite 518. April 2023

Limit Values to G 260 (Germany) - EASEE GAS

12.8 to 15.7 (group H gas)

0.55 to 0.75

Max. ground temperature

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/m3

Relative density d

Hydrocarbon dewpoint

Water dewpoint

CO2

Oxygen (O2)

Total sulfur (S)

Mercaptans (R-SH)

Hydrogen sulfide (H2S)

Carbon oxysulfide (COS)

13.6 to 15.81

0.555 to 0.700

- 2 °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

Seite 618. April 2023

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)

Seite 718. April 2023

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

Seite 818. April 2023

Gas Quality Reconstruction System Being Developed atE.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.

Seite 918. April 2023

Principle of Gas Quality Tracing System

Subsequent calculation of

superior calorific value Hs

normal density n

gas composition xi (11 constituents)

for delivery stations

Input data for calculation

Hs, n, xi at entry points

Volume flow at entry points

Volume flow at exit points

Grid topology

Auxiliary data (pressure, ...)

Seite 1018. April 2023

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 technologyexample: INCA, Union)

Further optimisation of costs

Improvement of Measurement Technology

Seite 1118. April 2023

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 CentreAccredited calibration laboratory / state-approved test

centre