In my experience with slurry tanks we always had a flush line controlled by a pneumatically operated valve in the neck of the discharge port to prevent just what you are describing. In my case it was a salt slurry tank and we used saturated brine for the flush. But you can use water or air as the flush. ■

If the tank fills to where there is overspill back to the gas line then you must introduce the appropriate HL & HHL switches to activate the flushing line mentioned by Gary. If you are overtopping without a flushing line then you are not solving the problem by more vigorous overtopping.

Do some more homework and find out the stability of your recent pulp. How long has this been going on? If your pulp is on the unstable side, say 6 - 8 on the chemical scale and has been so since the beginning then it looks like some bean counter refused to fit the necessary mixer.

It seems rather drastic to have to shut down a blast furnace because of a regular flashing danger: if that is indeed the case. You need to insert a temporary flushing line until you have a scheduled shut down which allows you to fit the level controls and proper flushing line along with the agitator. Some way down the line the agitator is going to fail and the flushing line can take over while the agitator is getting fixed. ■

Dear Sir:

Please send me a draft and some date such flowrate etc.to leemeasure@126.com. Maybe I can help you.

Leemeasure Charlie

Originally Posted by S.T.Selvam

At the outlet opening of slurry discharge hopper of the Pre-scrubber cum AGE scrubber (Blast Furnace Gas Cleaning Plant) is frequently getting clogged due to slow settlement and built-up process of sludge at the surface area of the outlet funnel. This causes full closure of the drain pipe of the slurry (dust + water) hopper of pre-scrubber and hence the tendency of entering of slurry in to the pre-cleaned gas line. How the clogging can be removed online with out stopping the operation of the pre-scrubber or the Blast Furnace. Kindly suggest suitable solution.

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