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Slurry pump plugging

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This topic contains 5 replies, has 3 voices, and was last updated by  Hedewandro Lucredi 5 years, 6 months ago.

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  • #26360

    Hedewandro Lucredi

    Our slurry pump is plugging a lot the suction filter. We are injecting a chemical slurry dispersant and it seems does not working. How can I check the dispersant eficiency ? What is it the typical consumption ? What is the best chemical for that ? What is the best point to inject ? How can I improve the chemical eficiency ? Any suggestion ?

  • #26446


    What is actually in the suction filter? What is the screen size (if it is coke)? In some instances, the chemical you are injecting could actually be hurting rather than helping.
    What does the suction inlet coming from the inside of the Main Fractionator look like. We had a chimney type suction that allowed the coke to settle in the bottom of the Main Fractionator. Some coke will be entrained and make it to the pump. Slurry pumps are generally robust enough to handle it. I think I would consider removing the suction filters if I had a chimney system in the Main Fractionator.
    If you want to keep the filters, do you have a way to backflush on regular intervals?

  • #26454

    Hedewandro Lucredi

    The filter screen size of the slurry pump is 9 mm. In fact the problem is the plugging of the equipments (heat exchangers) after the slurry pump because coke fine and catalyst deposition. It has a “huge filter” in the bottom of the main Fractionator in order to avoid to send “coke” to the slurry pump. We are using a slurry dispersant in the suction of the pump but it still plugging the pipe and heat exchanger. How can I check the dispersant yield ?

  • #26513


    I would contact the chemical vendor to see if they have a way to check the yield. You must keep the velocities up to prevent lay down. Once the plugging starts, the dispersant does not help as it will take the path of least resistance.

  • #26560

    Christopher Dean

    Another thought: : What is causing the coking/fouling of the suction screens/filters? You may want to review your bottoms temperatures. If you are using bottoms quench you may want to increase it to lower the bottoms temperature and increase bottoms velocities. The dispersion may help but there may be other reasons for your problem.

  • #27057

    Hedewandro Lucredi

    We do the analysis of the deposit in the slurry heat exchanger and it seems to be catalyst (Al and Si we found) a lot. It seems that the chemical that we are adding is not solving the problem (keeping the catalyst in suspension).

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