ACCURA: Sampling Device

High-Precision Sampling for Volatile Hydrocarbons

The PAC Accura is technically engineered to solve the challenges associated with sampling and injecting Liquefied Petroleum Gas (LPG) and pressurized gases into analytical instruments. In elemental analysis, the accuracy of the final result is heavily dependent on the quality of the sample introduction. The Accura provides a stable, controlled pathway that ensures the sample remains in its intended state—whether liquid or gas—until the moment of injection. This prevents the loss of light-end components and ensures that the concentration of trace elements like sulfur and nitrogen is representative of the bulk material.

Specialized LPG and Gas Injection Logic

The technical core of the Accura lies in its sophisticated injection logic, which is designed to handle different sample matrices. For LPG, the device ensures that the sample is kept under sufficient pressure to remain in the liquid phase during the measuring process, preventing premature flashing. For pressurized gases, it regulates the flow to ensure a consistent volume is delivered to the combustion furnace. This versatility allows a single sampling device to be used for a wide range of refinery streams, including propane, butane, and various process gases.

Maintaining Sample Integrity and Preventing Contamination

A critical technical requirement for trace analysis is the prevention of sample contamination and adsorption. The Accura utilizes inert materials in its flow path to ensure that polar compounds, such as hydrogen sulfide (H₂S) or mercaptans, do not stick to the internal surfaces of the device. This "surface passivity" is essential for achieving accurate results at the parts-per-billion (ppb) level. By providing a clean, non-reactive environment, the Accura ensures that the elemental analyzer receives the exact chemical profile of the original stream.

Advanced Safety and Leak Detection Systems

Handling pressurized flammable gases requires rigorous technical safety protocols. The Accura is equipped with integrated leak detection sensors and automated shut-off valves. If a pressure drop or a gas leak is detected within the system, the device immediately ceases operation and isolates the sample source. This automated safety response protects laboratory personnel and equipment from potential fire hazards. Furthermore, the system includes a purge sequence to safely clear the lines of residual sample after each analysis, preventing hazardous build-up.

Automated Calibration and System Validation

To ensure long-term analytical accuracy, the Accura features automated calibration routines. It can be programmed to inject certified gas standards at specific intervals to validate the performance of the entire analytical chain, from the sampling point to the detector. This technical validation is crucial for compliance with quality management systems. The device monitors injection pressure and flow rates in real-time, providing the operator with diagnostic data to confirm that the system is operating within its calibrated tolerance levels.

Seamless Integration with Elemental Analyzers

The Accura is designed to function as an integrated extension of PAC’s elemental analyzers, such as the ElemeNtS or Antek series. Technically, the sampling device communicates directly with the analyzer’s software, allowing for "one-software" control of the entire process. This synchronization ensures that the furnace is ready and the detector is stabilized before the Accura initiates the injection. This seamless connectivity reduces the complexity of the laboratory setup and eliminates the need for manual coordination between the sampler and the analyzer.

Compliance with ASTM D6667 and D7183 Standards

The technical configuration of the PAC Accura is strictly aligned with international test methods for pressurized samples, including ASTM D6667 (for sulfur in LPG) and ASTM D7183 (for nitrogen in gaseous hydrocarbons). These standards mandate specific injection volumes and pressure conditions to ensure valid results. By following these standardized protocols, the Accura ensures that the data generated is globally recognized and legally defensible for trade, quality control, and environmental regulatory reporting.

Digital Traceability and Operational Efficiency

The Accura provides comprehensive digital data management for every sampling event. The device records the injection pressure, sample temperature, and time-stamped logs of every run. This technical data is stored alongside the analytical results, providing a complete audit trail. By automating the sampling process, the Accura significantly increases laboratory efficiency, allowing for higher sample throughput with minimal manual intervention. This digital integration supports modern refinery operations that require fast, reliable, and traceable data for process optimization.

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