Method and system for stabilizing dry-based density of wood chips to be fed to a chip refining process

A method for feeding wood chips at a substantially stable dry-based density to a processing stage upstream of a chip refining process from a plurality of independently discharging sources of wood chips being characterized by one of a pure wood species and a mixture of wood species, said method comprising the steps of:

• i) estimating on-line a set of wood chip properties characterizing said wood chips to generate corresponding wood chip properties data, said set including at least one light reflection-related property, moisture content and dry-based density;
• ii) feeding said wood chip properties data at corresponding inputs of a reference model capable of comparing the estimated dry-based density with a predetermined dry-based density target to produce error data, and selectively modifying discharge rate set points of one or more of said wood chip sources to minimize the error data within fluctuation limits around the target;
• and
• iii) controlling the discharge rates of said wood chip sources in accordance with the set points to feed said processing stage with the wood chips at said substantially stable dry-based density.