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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