By late 2004 the Evaporator train at PRPD DMI was required to operate approximately 28% over design on a water evaporated basis to support significant increases in pulp production. A combination of high Evaporator throughput and overloaded vertical flow mist eliminators in the Effects resulted in excessive carryover of liquor droplets (organic material and soda) into the Evaporator condensates. In June 2007 the 4~th and 5~th Effects were retrofitted with high efficiency horizontal flow mist eliminators. This upgrade successfully reduced carryover in the Evaporator condensates, resulting in lower Bleaching chemical usage, reduced caustic make-up, and energy savings.
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