EXPERT FOCUS
REMOTE MOUNTING BENEFITS FOR EXTRACTIVE SAMPLE ANALYSIS
For any process, sensor head mounting is a critical design consideration which can have serious implications for long-term measurement performance and maintenance requirements.
With its integral sampling system, designed specifically for operation in some of the hottest and most extreme combustion environments, the SERVOTOUGH FluegasExact 2700 is an ideal choice for monitoring oxygen and combustibles in the most demanding hydrocarbon processing( HP) applications, including process heaters, utility boilers, thermal crackers, incinerators and furnaces.
In addition to the other benefits of the FluegasExact, Servomex offers both direct and remote mounting options to make access and maintenance easier, regardless of whether or not the desired measurement point is freely accessible.
While direct mounting is sometimes seen as the standard approach, remote mounting can offer a number of advantages, particularly for applications in the hydrocarbon processing industry.
In remote mounting, the sensor head is situated on a skid panel up to 30m( 100ft) away from the process, and is connected to the sample take-off point via an insulated sample line.
This sample line, and the exhaust lines, are heated to minimize the chance of sample condensation.
For longer sample lines, a second high-flow aspirator is used to create a fast loop of several liters per minute. The sensor head then uses its own internal aspirator to draw an appropriate sample from this fast loop, thus maintaining a good response time.
The moisture-rich, non-conditioned sample is passed under the sensor head and then fed back into the flow, giving a continuous measurement.
This system has three distinct benefits for HP applications. Firstly, it removes the sensor head from what would be considered a potentially dangerous environment for personnel to work in.
For example, thermal cracking processes for ethylene production are very hot, and are extremely uncomfortable to work next to for prolonged periods of time.
By moving everything away from the process and putting it on a remote panel, it allows a person to approach it and work easily, with far fewer health and safety risks.
Secondly, many of these processes are " zoned " and classed as hazardous areas.
FLUEGASEXACT 2700 SENSOR HEAD
CALIBRATION / GAS HANDLING VALVES
Example of a typical Servomex extractive system.
Permits are required and strict regulation imposed for working in such areas.
Removing the analyzer from the hazardous area can in many cases‘ de-rate’ the analyzer, as you are installing it in a safe area.
Also, moving the analyzer away from the process makes maintenance easier as the working environment is safer and more comfortable, and access is improved.
So it is clear that while direct mounting will continue to have an important place, the advantages of remote mounting should not be overlooked in aiding access, maintenance and safety in demanding hydrocarbon processing applications.
FLUEGASEXACT CONTROL UNIT
HAZARDOUS AREA PURGE SYSTEM
For more expert advice on remote extractive mounting visit servomex. com
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