Ratio analyzer delay
Thread Content
Recently, the company’s sulfur unit was put into operation, and there is a significant delay in the readings; it takes over 20 minutes for results to appear after making adjustments. AAI equipment is being used – do any of the experts know what could be causing this?
This is probably a problem with the instrument itself; generally, it takes about 5 minutes for a response to appear, and it takes around 2 minutes from when sample is injected to when the results are obtained.
This is just for reference. It’s not investing in chains either. Mainly relies on manual analysis
It seems like this takes too long; here, the change in the ratio, as well as the change in emissions at the rear, occurs in roughly 30 seconds!
The last edit to this post was made by qugd on 2019-6-8 at 20:36. I think the time delay inherent in the AAI analyzer itself shouldn’t be that large; it’s likely the sampling and preprocessing systems that cause such delays. Additionally, could it be that the flow rates set for the pipelines, dead volumes, and bypasses in the preprocessing system are too low, resulting in a slow sample flow rate? Ratio analysis refers to gas absorption colorimetry; the response time should be on the order of seconds, not minutes. Even if the sample lag time in the preprocessing system is taken into account, a maximum lag of 5 minutes is already quite long; a lag of 20 minutes is unacceptable. Furthermore, in the case of explosion-proof instruments with positive pressure purging, if the pressure and flow rate of the positive pressure purge air are insufficient, the time during which the instrument can operate properly after purging will also be delayed as a result.
In your case, it’s very likely that the analyzer has been clogged by sulfur. The analyzer is set to perform automatic purging for over 20 minutes, and the values only change after the purging process is completed. To resolve this issue, ensure that the temperature of the analyzer doesn’t drop too low, so as to prevent sulfur from solidifying and causing blockages; additionally, set a shorter interval for the analyzer’s automatic purging
Could it be a heating issue? Use 1.1 MPa steam to check, and take the opportunity to check the system pressure as well; low pressure leads to low load and reduced accuracy of the instruments
The ratio analyzer has a backflow time; we have encountered this issue before as well. The reason seems to be that the pipeline is a bit blocked, resulting in insufficient pressure, which prevents timely analysis and feedback.