Building on our years of experience in the Iron & Steel and Glass Industries, AMETEK Land provide a whole range of measurement solutions specifically designed for the Petrochemical industry. All are built to the highest standards of quality and reliability to ensure accurate measurements under plant operating conditions. The measurement of temperature at critical locations in the production process is essential for the full understanding and efficient control in this industry.
AMETEK Land can design and build special systems to meet your exact requirements including Hazardous area applications
Reformer Tube Temperature Monitoring
AMETEK Land offer two options for monitoring reformer tube condition
For periodic spot measurement the Cyclops 390 L Furnace Pro is a proven and accurate option
For continuous monitoring our NIR-Borescope provides a thermal profile inside the furnace itself
Temperature monitoring is of critical importance in the operation of all high temperature furnaces and reformers. Reformer tube life and efficiency is dependant on the temperature at which they are run. Failure to accurately measure temperature can result in premature end of tube life, lost production, or catastrophic tube rupture. Reliable temperature measurement can offer a number of benefits, including increases in plant efficiency and productivity, better prediction and planning of tube replacement as well as improved safety. All of these can help to lead to greater profitability for the company.
The efficient operation of a modern plant often depends on achieving the most from the steam reformer. Knowledge of the tube material skin temperature in a furnace designed to continuously heat fluids is often important, since excess temperatures can seriously reduce tube life, whilst conservative operating temperatures can reduce plant efficiency. A great deal of work has been done on methods of fixing thermocouples to tubes, to increase thermocouple life and the accuracy of measurement, but at high temperatures thermocouple life can be too short. A portable radiation thermometer overcomes these problems, meaning infrared technology is the only practical method available for temperature measurement in the hostile environments inside high temperature furnaces. This is a widely used technique within the petrochemical industry, yet it is known to be subject to a range of significant errors. Large errors (up to 100 ºC) can occur, depending on furnace geometry and operating conditions.
These errors are present for a number of reasons, including:
- Incorrect emissivity setting.
- Incorrect selection of operating wavelength.
- Reflections from neighbouring tubes, refractory walls, and flames.
- Absorption and emission of radiation by water vapour and CO2 in the intervening flue gas.
- Non ideal measurement practice.
It is critical that these errors are corrected; Land can offer a solution designed specifically for this problem.
Other issues include carbon deposits on the inside of the tubes. This can reduce the internal diameter of the tube and, therefore, the flow rate. The result of this can be hotspots forming and, ultimately, a complete blockage and melting of the tube.
The life of the steel tubes within a furnace can be a serious problem. With temperatures exceeding 1650 ºC, the tubes could not withstand the conditions without the cooling effect that the pumped product provides. If the flow is obstructed then tube life can be shortened considerably. Tubes can also develop hot spots for a variety of reasons.
Land Instruments International are able to offer 60 years experience in the Infrared temperature measuring industry and have the specialised skills and understanding of the principles required to minimise these errors and provide results that can be trusted to be accurate and reliable.
The uncertainty of the measurement must be known and evaluated. For this to be done accurately requires an advanced understanding of the statistical and mathematical methods behind the calculation. Uncertainty is crucial in determining the risk associated with the result of a measurement of tube temperature.
A Portable Solution
The Cyclops 390L is a dedicated, high precision, portable infrared thermometer, designed for accurate temperature measurement in furnaces, with a temperature range of 450 - 1400 ºC. The measured temperature is displayed in four simultaneous modes: continuous, peak, average and valley. Accurate sighting is ensured by the clear, wide angle (9º) field of view and small, clearly defined (1/3º) square measurement area. Focusing is variable from 1 m to infinity. The operating waveband (3.9 µm) has been carefully chosen for this industry, as it is a transmissive waveband for hot products, water vapour, and CO2 of combustion. At 3.9 µm these products are invisible, eliminating errors caused by absorption/emission bands present in combustion gases. If present in sufficient quantities the water vapour and CO2 vapour can make a 1 µm thermometer read falsely high, therefore thermometers reading at that waveband are unsuitable.
The Cyclops 390L provides both USB and convenient Bluetooth wireless technology. It also has on-board data logging, plus a software analysis system.
AMETEK Land recommends:
Thermal Imaging Solutions for Furnaces & Boilers
When thermal imaging inside refractory lined furnaces or boilers is required the plant operator is required to cut large openings in the refractory to enable viewing of the critical area. This can cause significant wasted energy from heat loss through the opening and can be difficult to keep the opening free from debris.
With the introduction of the NIR Borescope it is possible to accurately profile the temperature of the entire furnace with only a small opening in the refractory wall.