Alfa Laval S846 HFO Separator problem

[popeye62]

Are you stopping it for a reason (the bowl leaking) or just an operational decision, can you keep it running longer than a month? How many total hours on the machine? The 'o' rings including the rectangular rings and valve plugs should be good for six months or 4000 hours. What is the condition of the rectangular ring when you take it out (the one on the discharge slide)? Are you still wrapping the rings with Teflon tape as this could cause a leak? The rectangular ring is forced against the bowl body, creating a good seal by the closing water trapped under the slide which keeps the bowl closed. The rectangular ring is usually a very tight fit in its groove, how do you get it out and how do you get it in with Teflon tape around it? On the bottom of the rim of the discharge slide is a small hole where the water enters and acts behind the rectangular ring (this is how I used to remove the rectangular ring by using an air line to force the ring out of its groove). Check this water passage is clear and clean out if necessary also check the nozzles in the bowl body have not fallen out or blocked (the manual states that a 10% solution of acetic acid heated to 80 degrees is the way to remove limescale and soft iron wire for cleaning out nozzles but it is probably not limescale if you are using evaporator water). If the closing water is allowed to pass between the rectangular ring and the bowl body then it is similar to the water passing through the valve plugs to open the bowl. Use the right lubricants according to the manual (Silicon grease on the 'o'/rectangular rings). None of this though addresses the problem of running for a month and, presumably, carrying out a full discharge every hour without problems which means there is enough closing water to close and keep closed for over 700 ejections (in a month) so increasing the length of the closing water pulse won't help. Next time the bowl won't close try operating in manual and fill it full of water and try ejecting a few times. Is it an EPC-50 control panel? Are you changing the bowl seal (the white one) each time? Are all your spares genuine Alfa Laval? Could the issue be with the start programme which includes a calibration and a full ejection and is not carried out again unless the machine is stopped? Check the sequence in the manual.

[dumdum]

Hello
I have issue with lube oil purifier p626.
He is working normally for around half day making few discharge alone without any problem and after that i get pt4 low alarm and after when i go to restart i get alarm discharge feedback error and purifier trips. I change all o rings , 3 way valve , water block ( he is working properly without any leakage ) , transmitter but still i get this alarm sometimes i cannot even stsrt him but if i start he is working around half day maybe more without any problem no leaking nothing . And just to mention this alarm come only after dischsrge cycle . Also i swap the bowl from other purifier but problem still exist , other purifier is workingg normally. Any advice i will appreciated. Thank you in advance

[popeye62]

Hello dumdum. I presume that the oil is properly heated and a reasonable throughput. What is the separation time? As PT4 is the clean oil outlet backpressure, it suggests that there is no clean oil coming out of the machine. What is the reading of PT1 (the oil inlet pressure)? What is the reading of PT4 when it is operating normally? If oil is going in and not coming out via PT4 then where is it going? Is the sludge tank filling up via either a leaking bowl or through the water outlet. As this is a P-Type, is the correct gravity disc fitted? Check the alarm history: does the low PT4 alarm always come first and then the discharge feedback error alarm? The manual gives two reasons for the low PT4: the bowl is opening unintentionally or the water seal is broken. Either the operating water strainer is blocked or the water pressure/flow through MV10 (the conditioning/displacing water) is low (you need between 2b and 6b of pressure). Check the operation of MV10. Does the feed pump (dirty oil) need overhauling? Is the 3-way valve (V1) working ok? For the bowl opening: is the opening water valve (SV15) passing and opening the bowl randomly? All of the remedies are regarding operating water: no water, nozzle blocked, strainer clogged and valve plugs defective. Are the hoses connected correctly? Regarding the feedback error, this is a little more complicated. The manual refers to an installation parameter 6 (In6) if In6 = Yes then the machine is looking for a drop in speed during discharge. The manual says that the parameter is adjusted as a factory setting 12 (Fa12) and according to my manual the setting is 300 RPM (the range is 0 - 2000 RPM). However, if In6 = No then the discharge feedback error is a pressure measurement from PT1 (presumably it looks at the pressure to determine that the feed is off prior to a discharge) The setting of this is a process parameter 31 (Pr31) and according to my manual is set at minus -0.05b with a range of plus or minus 1.0b. Check these settings and ensure all the other settings have not been changed. Having said all that, it is probably the water.
Good luck, John

[izwicky18]

Hello everyone,
I am currently facing a problem with our HFO Purifier (Alfa Laval S876). After desludging, the temperature spikes up to around 130C and then slowly comes down back to the normal temp which is around 98C.
Unfortunately, the alarm cannot be resolved by simply raising the alarm time delay to 30s (max).
Checked the temperature sensors. All ok.
Checked the temperature controller. Seems to be controlling the valve positioner well. Also tried manually opening this temperature ctrl valve, but the problem still persists.
Three-way valve functioning well. During desludging, the feed recirculates back to the settling tank (not the heater).
Feed pressure ok. Feed pump filters cleaned.
This happens to two purifiers. One purifier works fine.
Please do share your thoughts. Thanks!

[dumdum]

120 minutes it is separation time .
Pt 1 pressure is 0.4 (no any problem with pt1)
When it is operating normally i keep 1.5 bar pressure on pt4.
When it is not increasing pt4 oil is going to overflow to sludge tank. Always is coming pt4 first and then after is coming dicharge feedback error.
It is not that bowl is opening unintenationally. So water block it is not leaking. When make discharge coming first displacment water then opening water then is discharge after that is going closing water after againg displacment water and after 3way v/v opens. That time pressure is not raising sometimes but sometimes yes thst way i am confused . P series no have speed sensor but i think maybe it is problem with speed of the bowl so i will try to inspect belt and berings and pads. Because if bowl not have proper speed this will affect to bowl to close.

[popeye62]

Hello izwicky18, I am familiar with a spike in temp after discharge as the fuel is usually circulating through the heater and this two minute 'short circuit' puts more heat in the fuel but I've never seen it that high or for that long. If the control valve is controlling the steam inlet correctly then it must be something to do with the flow. It seems that as you don't re-circ through the heater then there is a slug of fuel trapped in the heater (zero flow) and as your steam pressure is probably 8b which is a temperature of over 160 degrees C then maybe the residual heat in the heater is raising it to such a high temperature. Can you re-circ through the heater during discharge? Keeping some flow might keep the temperature down. John

[popeye62]

Dumdum, so if the oil is overflowing through the water outlet there is a lack of sealing water (same as displacement water). Perhaps there is an intermittent water flow problem as it sometimes comes back on line. Perhaps, other consumers starve it of water at certain times (?). If the problem is always after a discharge and not during separation then it doesn't suggest a slow leak but a failure to add sealing water after the discharge. Has the oil changed i.e. would a smaller gravity disc help? Certainly, the speed will affect the bowl closing. Have you tried running it in manual? Have you tried adding sealing water manually during the re-start sequence? Have you tried turning off the water and operating it as a clarifier (It's a bit of a work-up but it would confirm that the sealing water is the problem)? "sometimes i cannot even stsrt him" what prevents the start? Are there any other alarms at this time?

[Simardeep]

Hello friend s
I am getting transducer no response alarm on s866 purifier . This alarm is coming once in 24 hours . I already replaced the transducer with new one and also checked the sv10 valve but the problem is still there . Anybody please suggest how to trouble this problem

[popeye62]

Hello Simardeep, these spurious problems with separators are the most difficult. If it is fuel then it is likely on a one hour separation (?) so it is going through 24 discharges and then an alarm on the 25th. The controller is expecting a rise in the trigger value during Ti64 and Ti65 and when it doesn't come then you get the transducer alarm. The trigger is generated by the water added through SV10 (5.5 litres/minute for a S866 [SV15 11 l/m and SV16 2.8 l/m] checked with a calibrated bucket and stopwatch?). In my manual Ti64 = 60 seconds and Ti65 = 15 seconds which are factory settings. Have you tried a recalibration? When you go to start and it asks you 'Has the bowl been dismantled' and the other maintenance questions, press YES and it will calibrate itself with the right amount of water. To calibrate the flow rate through SV10, the programme uses Ti59 which according to my manual is 170 seconds which is looking for a rise in pressure at PT4 (so the outlet remains closed) of 0.2b (this is the setting of Fa6 in the manual). If it doesn't see it then you get an alarm. Check all your settings with the manual first. Good luck, John

[Simardeep]

Thanku man for your reply will see . Thanx for help

[Simardeep]

hello friends i
I am getting the Feed pressure PT1 LOW . That time the sequence is ti64 = 60 sec
can anybody please suggest something .
purifier model - s866 (hfo)

[Simardeep]

i am getting FEED pressure low PT1 low . that time the sequence is ti64=60 sec.
Discharge pressure of the feed pump is =2.5 bar =
Discharge pressure afterheater is also ok .
can anybody please suggest me something.

PURIFIER model - s866 (HFO)

[Simardeep]

i am getting FEED pressure low PT1 low . that time the sequence is ti64=60 sec.
Discharge pressure of the feed pump is =2.5 bar =
Discharge pressure afterheater is also ok .
can anybody please suggest me something.

PURIFIER model - s866 (HFO)

[popeye62]

So the Transducer - No Response alarm is no longer coming? Is it still discharging? Was PT1 Low part of the initial problem? What is the alarm limit for the feed (Pr15)? You can disable PT1 by setting Pr14 to 0.0b. If the pressure out of the pump is 2.5b then it is not low. PT1 is after the pump and heater and the temperature sensor and then V1; is V1 operating correctly not just appearing to operate? Are you getting a pressure on PT4? Can you run the machine in manual to test?

[chillmen]

The solenoid for V1? I'm not sure how that has fixed the problem but let's hope with fingers crossed. Put the air supply pressure to the v/v back to normal and Pr10 back to 3.0b or write it all down in your PMS and any other changes made. The next engineer needs to know.

hello sir. would you tell us exactly what to do.i have same problem ,.,i check v1 but seems okay,.i check what happening during the alarm triggered, i saw that pt4 increase and it takes time to decrease the pressure till alarm activates,,.