Powder doser

In the powder doser, limestone with a median particle size of about 12 pm is used. The flow rate of the stream is metered and used to control the limestone feed rate into a slurrying chamber. The resulting suspension is then discharged into the stream. Limestone utilisation rates, however, are only about 50 %. 

The slurry doser operates on a similar principle to the powder doser. It uses a pre-mixed slurry containing 70 % by weight of limestone (with a median particle size of about 1 pm), stabilised with a dispensing agent. Utilisation rates approaching 100 % are achieved. 

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