How to monitor internal leakage in plate exchangers?
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Steam is used to heat the cold oil through a plate heat exchanger; the steam condensate needs to be recovered. How can we effectively prevent oil from entering the boiler system along with the condensate due to leaks within the plate heat exchanger? How to achieve online monitoring?
For general acidic or alkaline substances or electrolytes, the method of using an online pH meter and a conductivity meter for simultaneous monitoring is employed. However, it’s not clear what type of oil this is; it’s unknown whether it has acidic or alkaline properties. If it doesn’t, then no electrolyte solution will be formed. It might be possible to add some substances that can ionize, but this would introduce additional corrosion risks, among other issues. Other solutions could also be considered.
Neither steam nor oil is corrosive, right? There’s no need to worry about the gaskets between the heat exchangers being damaged under high temperatures
Sampling can be done regularly or TOC can be monitored online
Electrical conductivity is installed on the steam condensate side for monitoring, but it still depends on which system has higher pressure
Yes, it’s the concern about potential leaks caused by this issue!
The idea is the same; the problem is that the pressures on both sides are variables, and generally the pressure on the oil side is higher. . . . .
After checking, it turns out that using conductivity measurement to monitor oil leaks is not very reliable; both types of oil have low conductivity, so the difference is not very noticeable. Do anyone else have any good suggestions?
It is recommended to first conduct sampling analyses to determine the conductivity of the oil and water. If the differences are indeed small, consider installing a small buffer tank; use a sight glass to check for the presence of an oil-water mixture, and install a level gauge for the oil phase. Once a high level is detected, activate the interlock to open the switch valves for discharging the condensate or directing it elsewhere, thereby ensuring that no oil enters the boiler water system. When assessing the pressure levels on both sides, it is not the normal operating pressure that matters – rather, the Dead-End pressure should be taken into account. For example: compare the situation where the inlet manual valve on the oil phase side is fully open and the outlet manual valve is fully closed, with the conditions on the water side
I have seen equipment for detecting oil spills at DOW Chemical. An alarm will be triggered immediately if it is detected
Hello, you mentioned the issue of pressure; closing the oil side outlet valve would mean stopping operation. What I need is real-time monitoring during operation. I would like to ask whether it is feasible to conduct monitoring at the boiler sampling point? Once oil ingress is detected, stop operations immediately, drain the boiler water, and clean it until the water quality meets the standards