Does anyone have the experiences of cleaning spiral wound heat exchanger? Especially the exchangers are operated in Rectisol Unit.
The feed gas is 65% H2, 33% CO2, 0.5% H2S and contained traces of soot and heavy metal. This feed gas entered the shell side of the exchanger and a part of the...
The differential pressure between sour gas and lube oil in a H2 expander remains a low value. It causes the spare lube oil pump start several times a day. When I decrease the sour gas pressure, the lube oil pressure located in upstream of bearing also become lower. I just want to increase the...
Some of our critical loops which could cause the whole plant to stop are designed with single loop. It means we can not allow any failure in this loop.
For example, an interlock of level switch causes to stop pump that will activate the other interlock and stop plant. We have a 2oo3 design for...
Dear all,
we have the CO2 Stripper which stripes the CO2 from the Methanol by N2.
Recently its differential pressure is increasing gradually from 0.35 to 0.45 Kg/cm2 in past 2 months. Sometimes as the differential pressure increased quickly and reached 0.5 Kg/cm2, the methanol will spill out in...
There are three expansion control valves in the bottom of H2 stripper in the cold box.
The normal process conditions are following:
1. Stripper operates at 18 kg/cm2.
2. The liquid CO on bottom of stripper flows paralleled through three expansion valves, but only one of the temperature of the...
Could some one tell me what is the difference between NaOH % and free NaOH %?
From analysis report for the caustic soda solution, only NaOH % data was detected and didn’t any free NaOH % contain in the solution. The laboratory person said the caustic soda was losing ability to remove hydrogen...
It was a terrible event that our reciprocating compressor cylinder has been heated to make the paint on the cylinder smoke found by CCTV.
We discovered the valve disk plate in the second stage inlet has broken, so the second stage didn’t work and cause the safety valve on the first-stage...
Dear all,
If the RTD sensor broke in the positive line, what will happen?
I find the signal in the PLC display didn’t change after I disconnect the positive line?
The RTD signal connect to M-system monitor switch for RTD type and output a digital signal to PLC system.
I measure the voltage...
Does any one know about the molecular sieve composition affecting the absorption ability?
The following data of 5A sieve from serching on the web:
0.80 CaO : 0.20 Na2O : 1 Al2O3: 2.0 ± 0.1 SiO2: x H2O
Does this mean I should get about 20 wt% of Ca ?
I'm interested in the absorption ability...
There are some critical interlock loops in our plant.
They were designed by 2 of 2 for DO TYPE point, that means
the loop have 2 solenoid valves for a device to prevent shutdown the plant if a solenoid failed.
My question is how do we know the solenoid valve is dead since the other one still...
In our plant we switch the spare pump running every month. Most pumps are centrifigual and operated under low temperature about -40 degree C. The process fluid is methanol contained 40PPM H2S. Since the pupm mechanical seal fail easily, We want change the policy to switch pumps every half month...
We buy the the perlite packages of 5kg/bag and pull it from top of cold box.
After commissioning start up, we find part of the cold box surface has a little condensation.
Does anyone give me advice how to solve the problem ?
best reagrd
Hazel
