Contaminated Turbine Condensate

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Experienced frequent cartridge change out due to high delta pressure for turbine condensate. Observed two colours of deposit; brownish and blackish. Loss of ignitions is 40 to 70% based on two times of used filter sampling analysis.

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6 Answers

  1. What is the source of condensate?  Since it is turbine condensate it is likely from power plant. Something is wrong with system. Loss of ignition 40 to 70 % indicates that there are non volatile solids in condensate. Please check conductivity. Cartridge filter only help to remove the insoluble solids. It means silica, calcium & iron are likely as their insoluble salt.

  2. What is the source of condensate?  Since it is turbine condensate it is likely from power plant. Something is wrong with system. Loss of ignition 40 to 70 % indicates that there are non volatile solids in condensate. Please check conductivity. Cartridge filter only help to remove the insoluble solids. It means silica, calcium & iron are likely as their insoluble salt.

  3. A big issue is the condensate purity.  Check the conductivity on a regular basis.  Check the silica levels in the boiler water, and boiler feed water.  silica carryover to the turbine will put it out of commission.  Condensate carryover is a big issue for a lot of different applications, including food processing and animal feeds where steam is used to inject into feed pellets for cooking and extraction.  In these application and in power plants steam and condensate purity is determined upstream and with proper condensate treatment.  So who thought up the idea of condensate filtration in the first place?  it shouldn't hurt anything, but the problem is not the filters: the problem is upstream.  Why?  Your job is not sales of new products or filters: your job is solving the problem. 

  4. Explain more about your plant...conventional or nuclear?  Base-loaded or dispatch operation?

    How long have you been using condensate filtration, and why was it needed in the first place?

    What is your % return on condensate/steam? How much steam loss do you have, such that larger volumes of make-up water are needed?  Is the make-up water saturated with oxygen?

    Have you tested the chemistry of the condensate to see what changed?

    1 Comment

    1. Fertilizer plant.  The cartridge is used to filter the iron mainly from piping. Previously the replacement of cartridge is done in six monthly basis. However after the recent shutdown, the dP increased to >1bar within 2 weeks. Actually big contribution from turbine condensate is 54% from the total condensate. In term of oxygen, the reading maintained below than 7ppb at the outlet of deaerator. If refer to surface condenser performance which maintained at the vacuum pressure and confirm no oxygen ingress into condensate system. Observed presence of methanol in the steam system due to tube leak at the methanol reactor and iron pick up which the result is higher than 0.02ppm.     

  5. first of all,  you have to check the pH, content of iron and yellow metals (Copper....) of the condensate ; do you apply any volatile treatment on the boiler? what kind of...? what kind of metallurgy do you have on the pimping system return ? you could apply something not suitable ....for example ammonium is corrosive against the yellow metals ....Another problems could be the length of the piping system....Content of Oxygen ....

    1 Comment

    1. Confirm no yellow metal. AVT (O) applied currently with amine base for pH controller. Carbon steel at the return condensate t demin plant. Length of piping is 100m and observed significant pH dropped in the turbine condensate that maintain at 8.5 to 8.8 against the BFW is 9.2 to 9.4. Confirm no oxygen ingress based on DO reading at the bottom deaerator and able to maintain vacuum pressure at the surface condenser.

  6. Have you checked condensate pH? Are there any previous corrosion studies? Do you have steam line treatment ?  If so, what type?  What is your make up water source?   All these can play a roll on the corrosive nature in your system.

    1 Comment

    1. pH in turbine condensate is 8.5 to 8.7. None study was done for corrosion studies. pH controller with amine is the steam line treatment. Make up water is the municipal water that treated at Demin Unit including the condensate.