New in Gas Processing Technology
B. ANDREW, Technical Editor
Thermal imaging for furnace tubes
AMETEK Land’s Near Infrared Borescope (NIR-B) 3XR enhanced thermal imager is helping Air Liquide continuously measure the temperature of tube walls within its steam methane reformers (SMRs). Air Liquide’s SMRs are critical assets, and their safe and reliable operation is of high importance.
However, SMRs are also challenging assets to maintain and operate. Some of the most common problems in reformer operation are seen in burner, flue gas distribution and catalyst systems. All of those problems can directly affect tube wall temperature (TWT) and tube life, and lead to premature tube failure. These issues also can lead producers to be overly cautious with TWT and lose valuable production every year.
Air Liquide required a solution that delivered highly accurate and more complete measurements of the equipment and process, compared with spot temperature measurements, while operating in a hazardous environment. The Near Infrared Borescope provides a high-resolution thermal image with real-time, high-accuracy temperature measurements of both the tube wall and the refractory wall surface, allowing for background compensation.
Developed specifically to operate in the hazardous areas of a steam methane reformer, the NIR-B 3XR is ATEX and IECEx approved and CSA certified. It is a short-wavelength radiometric, infrared borescope imaging camera, which measures temperatures in the single range of 600°C–1,800°C (1,112°F–3,272 °F) and utilizes the latest wide-dynamic-range imaging technology. This solution was found to be ideal for Air Liquide’s industrial gas application, in which high differential temperatures were present in the field of view, such as in the tube and furnace walls.
A live trial of NIR-B was conducted at a pilot plant in Spain with the support of the supplier team. The trial allowed the operators to fully test the instrument within their specific, harsh environment. Air Liquide was able to confirm the instrument’s suitability and prove its role in enabling and enhancing tube know-how. The borescope was installed through the furnace wall, in front of the tubes within the chamber. The thermal imager was connected to the control room via a field connection box.
Air Liquide uses the functions available within LIPS NIR-B thermal imaging software to monitor TWT constantly, and to receive early warning of increasing temperatures. The software allows operators to spot and respond immediately to problems such as hot spots and bands on the tubes, refractory damage and flame impingement.
Air Liquide uses the Isotherm temperature measurement mode within the software to highlight areas of a thermal image within a selected temperature range. Areas within the isotherm’s range are displayed in chosen colors for clear visibility, to achieve a comprehensive understanding of tube performance. With the confirmation that its plants are increasing know-how by continuously measuring the temperature of tube walls, Air Liquide’s research
and development team approved the NIR-B 3XR thermal imager for potential installation in additional SMRs.
Small-line flow measurement
Fluid Components International (FCI) offers thermal dispersion flow measurement technology with no moving parts in its ST75 Series, ST100L air/gas flowmeters and FLT93L flow switch. The technologies provide solutions for use in 0.25 in.–2-in. (DN6–DN50) pipe or tubing.
They are designed for use in areas where low flows, wide turndowns, dirty fluids, and hazardous or harsh installations are among
the application factors.
The flow instruments offer advantages for service in a wide range of applications: plant, building or lab gas submetering, small inlet air/gas feed lines for boilers, gas relief valve monitoring, chemical injection, compressed air systems, cogeneration or combined-heat-and-power gas fuel measurement and control, sampling systems, and more.
Many small process line applications are difficult to measure reliably with high repeatability, due to variations in temperature and pressure, and have wide flowrates. FCI’s thermal flowmeters and switches are unaffected by, or have onboard compensation for, temperature and pressure changes. In addition to detecting low flowrates, they also provide 100:1 turndown as standard.
FCI’s small-line air/gas flowmeters and air/gas/liquid flow switches combine state-of-the-art electronics technology with application
fluid-matched flow sensors and laboratory calibration. They are designed for demanding plant operating environments.
The thermal flow sensor technology relies on the relationship between flowrate and cooling effect. With no moving parts and minimal invasiveness, the meters and switches provide a repeatable, accurate, low-cost, easy-to-install solution with long service life,
and they require virtually no maintenance.
FCI’s ST75 Series air/gas flowmeters are ideal for lines sizes from 0.25 mm (6 mm)–2 in. (51 mm). Gas or air measurement accuracy is available up to 1% of reading, ±0.5% full scale. The ST75 meters feature a wide 100:1 turndown and measurement accuracy from 0.01 sft3m–
559 sft3m (0,01 nm3h–950 nm3h), depending on pipe size.
The meter’s electronics are housed in a rugged, IP67-rated enclosure with dual conduit ports in either NPT or M20 threading. The instrument comes standard with dual 4-20 mA outputs and a 500-Hz pulse output. The models ST75A and ST75AV include HART- and NAMUR-compliant 4-20 mA outputs, an SIL compliance rating and a 2-yr warranty. Global agency approvals for Division 1/Zone 1 HAZEX installations include FM, FMc, ATEX, IECEx, EAC and others.
The ST100L air/gas flowmeter is a next-generation instrument that combines feature- and function-rich electronics with advanced flow sensors. It is designed in a spool piece configuration in 1-in., 1.5-in. or 2-in. tubing, has schedule 40 and schedule 80 piping, and has an all-welded design to ensure no leakage when used with volatile gases like hydrogen. It measures air/gas flows from 0.0062 sft3m–1,850 sft3m (0.01 nm3h–3,140 nm3h), with superior accuracy to ±0.75% reading, ±0.5% full scale; and repeatability of ±0.5% reading.
Whether the plant’s output needs are traditional 4-20 mA analog; frequency/pulse; or advanced digital bus communications, such as HART, FOUNDATION Fieldbus, PROFIBUS or Modbus, the ST100L flowmeter is available with any output. Its digital bus communications are certified and registered with HART and FOUNDATION Fieldbus.
The FLT93 flow switch has been designed for use and long service life in rugged and harsh operating environments. It is available in both aluminum and stainless steel IP67-rated housings; carries HazEx agency approvals for FM, FMc, ATEX, IECEx, EAC, Inmetro
and NEPSI; meets Canadian Registration Number and European Pressure Equipment Directive and is SIL 2-compliant. It is available in a number of wetted materials and process connection options, and has universal DC/AC power supply.
Foam test kit for amine
Amine Optimization Co.’s Amine Solvent Foam Test Kit allows for consistent testing of amine for foaming height and stability, and the creation of a historical database of foam conditions. It also helps create a baseline for current/new amine, monitor amine over time to predict foaming problems before they occur and identify changes in feed correlating with changes in amine foam tendency. Various antifoams can be tested for optimum effectiveness.
Detector for toxic and combustible gases
United Electric Controls has introduced a WirelessHART gas detector that can monitor the presence of harmful gases for more than 5 yr without a battery replacement. The Vanguard Gas Detector interfaces with the existing plant network to provide continuous, economical detection of hydrogen sulfide and methane gases.
Wireless technology can reduce continuous monitoring costs by up to 90%. This makes it affordable to deploy sensing devices at more locations to detect leaks that a limited number of wired units might not notice until the situation advances to more harmful levels.
Contributing to the value of the Vanguard detector is its use of lithium metal technology. Combined with low-power components and advanced power modules, the technology can extend battery life beyond 5 yr, which is significantly longer than existing offerings operating under the same conditions. The extended battery life reduces both energy and maintenance costs.
Wireless devices signal a gateway that can be connected to a fire and gas control system, a fire station, a distributed control system or a programmable logic controller host for processing. The wireless signals can be designed using any network protocol, but standard open protocols, such as WirelessHART, have specific advantages. Data from multiple monitoring points can also provide predictive and preventive maintenance capabilities. For example, measuring the amount of background hydrogen sulfide and methane in the air and comparing it over time can provide an early indication of a problem.
WirelessHART 7.2 technology carries signals to local 128 × 64 pixel digital displays or other IEC 62591 compatible connections—all of which integrate seamlessly with existing supervisory control and data acquisition or asset management systems. The Vanguard detector has been designed and tested to interoperate with Emerson Smart Wireless Gateway 1410 and 1420.
The Vanguard detector can be mounted anywhere and dropped easily into any WirelessHART network by inputting the network ID and join key. The unit automatically senses the detector type and configures it. Seamless, plug-and-play interoperability saves additional setup time and effort. Class 1, Divisions 1 and 2 certification and an explosion-proof and intrinsically safe design help ensure trouble-free operation in hazardous environments. The unit also has ATEX and IECEx approvals.