Analytical Instrumentation

Gas Analyzer Sampling System

Sample Handling System in Gas Analyzers
  • Effective gas analysis depends heavily on the proper collection of gas samples from the pipeline. 
  • The sampling system equipment must constantly filter and deliver gas samples to the gas analyzer. 
  • Dust, condensate, and corrosive chemicals can interfere with gas analyzer performance and limit their lives. 
  • As a result, the sample system is an extremely important component in the process of addressing these difficulties. 
  • Key characteristics include sample conditioning, particle filtration, condensate management, corrosion-resistant materials, hot sampling lines, continuous purification, precise flow control, and automatic calibration. 
  • A well-designed and maintained sampling system provides accurate gas analysis results while also extending the life of gas analyzers by reducing the influence of potentially dangerous elements and conditions.

The sample handling system is an essential element in process analysis. It is the physical assembly of fluid-processing components designed to prepare the sample in a way that is compatible with the analyzer being used.

What is Sample Handling System?
  • The gas extractor designed for process gas analyzers has advanced features such as a heating system a stainless steel filter with a standard mesh size of 40 micrometers, a Teflon-heated sample line, and standard pneumatic blowback. 
  • This combination not only assures accurate gas analysis in industrial circumstances but also allows for easy monitoring of dust remaining conditions on the gas analyzer’s front panel.
Sample Gas Extractor for Process Gas Analyzer
  • The stainless steel filter, with a standard mesh size of 40 micrometers, acts as a strong filtration component, eliminating particulate matter and contaminants from the sampled gas stream. 
  • This protects downstream components, which contributes to the gas analyzer’s durability and performance.
Teflon Sample Line:
  • Complementing the filtration process is the Teflon heated sample line, known for its chemical inertness and high thermal stability. 
  • This component plays a crucial role in maintaining the integrity of the gas sample during transportation to the analyzer. 
  • The integrated heating element prevents condensation, guaranteeing that the sampled gas remains in a gaseous state for accurate analysis.
  • The gas extractor includes a standard pneumatic blowback mechanism, enhancing efficiency and longevity. 
  • This self-cleaning feature for the stainless steel filter prevents clogging by dislodging accumulated particles at regular intervals, ensuring consistent performance over extended operational periods.
  • The Teflon heated sample line, which is known for its chemical inertness and great thermal stability, complete up the filtration process. 
  • This component is critical in ensuring the gas sample’s integrity throughout transportation to the analyzer. The integrated heating element avoids condensation, ensuring that the collected gas is gaseous for reliable analysis.
  • This gas extractor is unique in that it can monitor dust adhering conditions on the front panel of the gas analyzer. 
  • This means that maintenance workers can easily assess the cleanliness of the analyzer’s front panel, allowing proactive measures to be taken to eliminate any dust accumulation that may impair performance.
  • The gas extractor’s extensive features not only assure precision in gas analysis, but also provide a comprehensive solution by adding a heating mechanism and the ability to monitor dust adhering conditions. 
  • This makes it a great option for industries that require both accurate analysis and real-time maintenance monitoring in demanding industrial conditions.
  • A gas sampling line with a mist filter is essential to gas analysis systems because it effectively removes drain, mist, and dust from the measured gas. 
  • The mist filter keeps the gas sample free of liquid droplets, fine aerosols, and particulate matter, ensuring gas measurement accuracy and preventing analyzer damage. 
  • This filtering is particularly important in areas subject to condensation or containing airborne pollutants. 
  • Gas sample lines with mist filters are used in a variety of industries, ensuring the reliability and precision of gas analysis instruments in a wide range of applications, from environmental monitoring to manufacturing operations
  • A safety drain trap, which is split into two chambers for positive and negative pressure, maintains safety by monitoring and regulating sampling gas pressure. 
  • This design prevents cross-contamination while maintaining controlled pressure conditions. 
  • The trap’s dual-room construction improves safety precautions, making it an essential element in gas sampling systems that require precise control of pressure for accurate and reliable analyzes in a variety of industries.
  • The gas aspirator pump efficiently extracts sample gas, making it easier to transfer for analysis. 
  • This pump uses suction to draw gas into the sampling system, providing for accurate and dependable observations. 
  • The gas aspirator pump is an essential component in gas analysis arrangements, ensuring efficient sample collecting and accurate analytical findings.
  • The electronic gas cooler is a critical component in gas analysis systems, using complex thermoelectric cooling to reach a low dew point of around 2 degrees Celsius. 
  • This cooler protects the integrity of gas samples by efficiently eliminating moisture from the sampling gas and preventing condensation within the analyzer. 
  • Its precise temperature control and energy-efficient design make it perfect for applications that require low dew points for accurate and dependable gas measurements, such as environmental monitoring and industrial processes.
  • The solenoid valve is essential for introducing calibration gas and is used in both automatic and manual calibration processes within gas analysis systems. 
  • In automated calibration, the solenoid valve responds to electrical impulses to accurately control the flow of calibration gas. It allows operators to fine-tune the calibration process by making manual adjustments. 
  • This dual feature offers flexibility in calibration methods, contributing to the accuracy and reliability of gas analyzers across varied applications
  • The membrane filter, constructed of PTFE (polytetrafluoroethylene), plays an important function in gas analyzers by removing dust particles from the sampled gas. 
  • This particular filter not only improves gas analysis accuracy, but it also allows you to monitor dust adhering conditions on the gas analyzer’s front panel. 
  • Its PTFE substance provides excellent filtration while also being chemically resistant and easy to maintain. This combined feature of dust removal and real-time monitoring improves the reliability of gas analysis systems.
  • The flowmeter(flow checker) is an important component in gas analysis systems since it allows the sample gas flow rate to be adjusted and monitored. 
  • The device provides exact control over the gas flow, allowing for reliable measurements. It plays a critical role in ensuring optimal conditions for accurate and repeatable gas analysis across many applications.
  • Standard gas cylinders play an important role in gas analysis by performing as reference gasses for calibrating the zero and span of analyzers. 
  • Six cylinders containing zero gas, air, and span gasses such as NO, SO2, CO, CO2, and O2 are required to ensure accurate and reliable readings in a variety of applications including environmental monitoring, industrial processes, and laboratory environments.
Standard Gas Cylinders
  • The NO2/NO converter is a critical component in NOx analyzers, using a specific catalyst that efficiently converts NO2 gas to NO. 
  • This conversion technique provides precise detection of nitrogen oxides. The converter is important in environmental monitoring and industrial processes since it helps to accurately analyze NOx emissions.
  1. Particle Filtration: Removes particulate matter, safeguarding downstream components and ensuring consistent analyzer performance.
  2. Condensate Management: Prevents condensation in the gas sample, maintaining its gaseous state for accurate analysis.
  3. Corrosion Resistance: Utilizes corrosion-resistant materials, extending the life of components and ensuring long-term accuracy.
  4. Hot Sampling Lines: Prevents sample cooling during transportation, avoiding condensation and preserving sample integrity.
  5. Continuous Purification: Eliminates impurities from the gas stream, providing a consistently clean sample for analysis.
  6. Precise Flow Control: Maintains a controlled flow rate, crucial for accurate measurements and reliable gas analysis.
  7. Automatic Calibration: Enables regular calibration without manual intervention, enhancing accuracy over extended operational periods

Infrared Gas Analyzers (IR-GAs) are used in the last stage of the sample handling system in a process plant’s analyzer shelter to monitor and manage gas concentrations. The NOx, SO2, CO, CO2, and H2 Infrared Analyzers, together with an O2 Analyzer, provide an entire suite for monitoring gasses in industrial processes.

These infrared gas analyzers work on the principle of infrared absorption, which uses the specific wavelengths absorbed by different gasses to calculate their concentrations. The analyzer shelter creates a controlled environment to provide stable and accurate results while protecting the instruments from external factors that could impair their performance.

  1. NOx (Nitrogen Oxides): Measures the concentration of nitrogen oxides, crucial for assessing emissions and combustion efficiency.
  2. SO2 (Sulfur Dioxide): Monitors sulfur dioxide levels, aiding in pollution control and compliance with environmental standards.
  3. CO (Carbon Monoxide): Analyzes carbon monoxide levels, essential for combustion optimization and workplace safety.
  4. CO2 (Carbon Dioxide): Measures carbon dioxide concentrations, providing insights into combustion efficiency and environmental impact.
  5. H2 (Hydrogen): Monitors hydrogen levels, particularly relevant in industrial processes where hydrogen may be present.
  6. O2 (Oxygen): Analyzes oxygen levels, crucial for combustion control and optimizing fuel-to-air ratios.

The Infrared Gas Analyzers generate electrical signals as output, representing the concentrations of the respective gasses being analyzed. These signals are utilized for various purposes in monitoring and controlling industrial processes.

  • The signals from NOx, SO2, CO, and CO2 analyzers are essential for monitoring and controlling emissions. Compliance with environmental regulations and assessing the environmental impact of the process are key considerations.
  • The CO and O2 analyzer signals contribute to optimizing combustion processes. By adjusting fuel-to-air ratios based on these signals, operators can ensure efficient combustion and minimize pollutants.
  • Monitoring H2 levels using the analyzer helps ensure workplace safety, especially in environments where hydrogen may pose a risk.
  • The signals from these Infrared Gas Analyzers are integrated into a control system, allowing for real-time adjustments to the industrial process. 
  • For instance, if NOx emissions exceed predetermined limits, the control system can trigger corrective actions, such as adjusting combustion parameters or activating pollution control devices.

Sundareswaran Iyalunaidu

With over 24 years of dedicated experience, I am a seasoned professional specializing in the commissioning, maintenance, and installation of Electrical, Instrumentation and Control systems. My expertise extends across a spectrum of industries, including Power stations, Oil and Gas, Aluminium, Utilities, Steel and Continuous process industries. Tweet me @sundareshinfohe

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