Emerson Exchange 365

In reply to Jim Cahill:

Consider replacing the mechanical gauge with a wireless pressure gauge - electronic. It doesnt have moving parts so it is less affected by vibration. learn more from this essay: www.linkedin.com/.../new-pressure-gauge-can-read-from-kilometer-away-jonas-berge

I have radar level installed on methanol tank but the level differs in the trend and not stable i have read that the radar antenna must be covered by dielectric transparent material to protect antenna from vapors and like that i didn't star yet to apply this idea , any advice?

In reply to Jim Cahill:

Measurement drift over the period of a day typically happens due to the impact caused by ambient temperature variations (day and night or afternoon and evening) which can be particularly amplified on long capillary installations used for tall columns. In order to avoid these errors one possibility would be to use an Electronic Remote Sensor System which consists of two transmitter connected to each other via an electrical cable and powered by the existing power supply. This would avoid the use of capillaries and hence reduce measurement drift. It is also possible to get a total system performance calculation done so that you are aware of the performance of the system before installation.

In reply to Ary Wibisono:

In the combustion process of burning any fuel there are combustion emission gases generated. Where there is lean burning mixture , Oxygen rich , there is very little CO produced (less than 100ppm) as there is typically complete combustion of the fuel . When the furnace or process heater mix become rich, i.e all O2 is consumed and you have unburned hydrocrabons , the CO level very rises in excess of 1000ppm. Some plants use only O2 level of measurement , typically ensuring the air blower always delivering O2 , never allowing the rich mix. However some operators use the CO as an indication of poor burner performance . In the furnace or heater profile bad burner can produce CO , even the O2 average level is still sound . Therfore using both O2 and CO becomes a valid measurement strategy.

In reply to one10zero:

We have a Process Seal Antenna to combat condensation, vapor and deposition of process liquid on the antenna. A standard stainless antenna may not be suitable when you have coating tendencies. Our Non-Contacting Radars can handle upto a minimum dielectric of 1.4. So, I suggest you check the dielectric constant of your application together with the antenna type.

In reply to Charles Johnson:

is there a hydrogen analyzer that can tolerate high H2S for flare monitoirng

what is minimum water content in a solution when we want to measure pH of H2S solution inside a tank.

In reply to Jim McLelland:

Quotes : "When the furnace or process heater mix become rich, i.e all O2 is consumed and you have unburned hydrocrabons , the CO level very rises in excess of 1000ppm". DOes it mean COe is more valid measurement to determine perfect combustion rather than measure CO only? This is due to COe means Combustible which not only CO but other HC can consider combustible.

In reply to Ary Wibisono:

The measurement of Oxygen cannot be ignored. You need the O2 measurement to ensure you stay on the "good" side of the combustion curve , i.e. you want some amount of O2 to be present. Too much O2, you waste energy , to little and heater goes lean and have a rich mixture in the flu.
Typically coal fired power plant would control O2 at best 3.0 to 3.5% O2 . For a natural gas fired burner the control point on O2 can be taken down to 1.0-1.5% .
The COe sensor by definition is CO equivalent , it may respond to a certain degree to other components( refer to the vendors data sheet for this detail). Whether CO or COe , the measurement does have meaning when looking at poor combustion e.g. due to poor burner condition or poor mixing of the fuel air in the burner section of the process heater . ON large process heaters i.e. ethylene furnace for example . Three O2/ Coe analysers probes can be placed across the heater to profile burner performance. As a practical example you can have two of these analyser probes indicating minimal COe ( less than 50ppm ) and one indicating 1500ppm this infers an issues with a burner section in the furnace.

In reply to Ary Wibisono:

Can you specify the application. Is this pH measurement in a sour water stripper ? I you can pass on process composition and conditions i.e pressure and temperture I can more realistically answer you question . The issue regarding the amount of water is related to composition you can have . Example : a water slurry of NaOH which at 80 degC flows , at 40 degC does not . Look forward to your reply.

In reply to Jim McLelland:

It is a chemical process plant where one of process produce H2SO4 (not H2S as per previous post). They want to control quality of H2SO4 at its tank before proceed to other process. Itemperature are about 40 deg C. I will ask for detail purpose of measuring qulity of H2SO4 and will email you once I has.

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Rachelle McWright: Business Development Manager, Dynamic Simulation: U.S. Gulf Coast

In reply to Jim McLelland:

Thank you Jim, reason I'm asking this CO & COe, my client, a coal fired power plant has installed O2 analyzer but from their energy efficiency department they want to have more parameter to determine combustion efficiency by adding CO parameter. What is the best solution in your perspective, whether to add CO analyzer (as per customer opinion) or COe analyzer or just O2 analyzer is more than enough to determine comsbution efficiency.
Furthermore, does anyone in this forum has a idea or some article for combustion efficiency solution which not only covers analyzer but also from system control that can regulate air blower and fuel feed based on analyzer inputs to achieve ideal combustion rate.

In reply to Ary Wibisono:

Ary , I will contact our PSS group and find out who does combustion control strategies. You can also make enquiries with the Emerson PSS control group in your area.