A Fiscal and Process Controller for a Hardboard Mill
Hardboard is manufactured by feeding wood chips into a pressurised preheater (digester). The dry heated chips are separated into fibre by grinding discs (defibration) and mixed with water to form pulp. The pulp is fed into a series of chests where it is mixed with a number of chemicals and water. The pulp is then dewatered on a machine wire screen to form a wetlap. The wetlap is pressed and heated to form hardboard sheets. A plant diagram is shown in Figure 1.
KeywordsFibre Quality Smith Predictor Flow Valve Board Type Flow Control System
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