The Natural Gas Analyzer (NGA) is a high-accuracy gas chromatographic system designed for the comprehensive analysis of natural gas composition and energy properties in accordance with major international standards. Accurate natural gas analysis is critical, as even small deviations in BTU and calorific value can result in significant economic impact. The NGA series provides reliable, repeatable, and standards-compliant measurements for custody transfer, process control, and quality assurance.
The commonly used NGA-2A Extended configuration is a dual-channel gas chromatograph based on the Thermo Trace GC1600 platform, offering high flexibility, modularity, and uptime. The system is equipped with three diaphragm valves, packed and capillary columns, and TCD and FID detectors to enable full compositional analysis of hydrocarbons, permanent gases, and sulphur compounds.
In the TCD channel, CO₂, C₂, and H₂S are analyzed on a Hayesep column, while H₂, O₂, N₂, CH₄, and CO are separated on a molecular sieve column. The FID channel measures hydrocarbons from C1 up to C8 and higher (up to C20) with excellent baseline separation, including neo-pentane. Micropacked columns and valves are housed in an independently heated valve oven for optimal stability, while the capillary column is installed in the GC oven with temperature programming.
The NGA system features integrated data processing and calorific value calculation according to ISO 6976, including gross heating value, density, and compression factor. All calculations are fully embedded in the Chromeleon™ data system, eliminating the need for external software. Calculations and reporting are executed automatically after each analysis, ensuring a streamlined and user-friendly workflow.
A wide range of configuration options allows the NGA to be tailored to specific analytical requirements, including low-level sulphur detection using FPD or PFPD, helium and hydrogen analysis using alternative carrier gases, stream selection for multi-sample analysis, and optional mass spectrometer integration for ppb-level detection of sulphur compounds, siloxanes, terpenes, and ammonia. With robust construction, standardized methods, and flexible configurations, the NGA is a future-proof solution for modern natural gas analysis.
| Details | Specification |
|---|---|
| Analyzer Type | Gas Chromatograph for Natural Gas Analysis |
| Standard Methods | ASTM D1945, D1946; ISO 6974, 6975, 6976; GPA 2261, 2177, 2186, 2286 |
| Typical Configuration | NGA-2A Extended |
| GC Platform | Thermo Trace GC1600 |
| Channels | 2 (TCD + FID) |
| Valves | 3 diaphragm valves (long lifetime) |
| TCD Analysis | CO₂, C₂, H₂S (Hayesep); H₂, O₂, N₂, CH₄, CO (Molsieve) |
| FID Analysis | Hydrocarbons C1 to C8+, up to C20 |
| Columns | Packed, micropacked, and capillary |
| Calorific Value Calculation | Integrated per ISO 6976 |
| Data System | Chromeleon™ CDS |
| Analysis Time | 9 min (up to C8); 20 min (up to C20) |
| Minimum Detectability | TCD: <0.01%; H₂S: 0.05% FID: <10 ppm hydrocarbons MS: <1 ppb (sulphur, siloxanes, terpenes) FPD: <200 ppb sulphur PFPD: <25 ppb sulphur |
| Dynamic Range | TCD: 4 decades; FID: 7 decades |
| Repeatability | <0.1% RSD for CH₄ |
| Sample Tubing | Sulfinert® inert tubing (H₂S compatible) |
| Power Supply | 220 V ±10%, single-phase, 16 A, 2.5 kVA |
| Optional Modules | FPD/PFPD, MS, helium & hydrogen channel, stream selector |
| Compact Version | CompactGC 4.0 (≈2 min runtime) |
- Natural Gas Quality Control
Determination of gas composition, calorific value, and heating value. - Custody Transfer & Commercial Gas Trading
Accurate BTU and energy value determination for billing and contracts. - Gas Processing & Transmission
Monitoring of permanent gases, hydrocarbons, and sulphur compounds. - Pipeline & Distribution Networks
Compliance testing with international gas standards. - LNG & Gas Storage Facilities
Verification of composition consistency and purity. - Environmental & Sulphur Monitoring
Trace-level detection of H₂S and sulphur compounds.
