| 摘要 |
Control of pulp and water flow rates out of a bleaching tower in a multistage pulp bleaching process wherein each stage comprises a bleaching tower and a washing drum, comprises the steps of (a) measuring total weight of pulp composition per square meter on at least one washing drum and from such measurement and the speed of rotation and area of the washing drum surface and the consistency of pulp composition, determining the total weight per unit time of pulp and of water coming out of the bleaching tower previous to said washing drum, and (b) controlling the rate of pulp and water flow out of said previous tower based on the determination of the total weight per unit time of pulp and of water as determined in step (a), and (c) controlling the amount of bleaching chemical flow to the pulp going to any following stage to match the pulp flow rate as determined from the measurement of step (a) and the percentage of bleaching chemicals to be applied. Step (a) is readily carried out utilizing a backscatter nuclear radiation gauge or capacitance measuring instrument or a microwave cavity perturbation apparatus. The result is a more uniform rate through the process and improved control over bleaching chemicals addition.
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