The mixing of slow-drying and fast-drying lumber in the same kiln charges is a significant cause of drying-related degrade, unnecessarily high energy costs, and overall underutilization of your fiber source.
This is not an optimal situation, but most mills continue to do it.
An accurate and reliable sawmill-based green lumber sorting system, that separates lumber by total (green) density, is an effective tool to sort lumber into slower and faster drying categories, in order to help optimize dry kiln schedules, save energy, and improve overall lumber grade.
When lumber mills apply green sorting technology, the positive financial benefits begin to accrue almost immediately.
The LDS-200 Green Lumber Sorting System is a proven, non-contact method of accurately sorting lumber in the sawmill, using a driability parameter based on a proven total density approach.
The LDS-200 Green Sort Process
- Four gamma sources are installed underneath the lumber flow, between chain races of your sorting chain.
- A detector for each source is installed above the lumber travel. As the lumber passes over the sources, gamma rays pass into the boards.
- The amount of rays that actually pass through the lumber are measured by the detectors, giving an accurate measurement of the total density of each piece of lumber.
- The detectors then communicate the gamma ray count information for each piece of lumber to the LDS console, where an immediate assessment of the board’s green density is determined.
- The LDS console then immediately sends the measured density value for each board to the mill’s sorter controls.
Benefits of Implementing a Green Sort System at your Mill
Green lumber sorting allows for accurate categorization of lumber for kiln drying, which enables kiln operators to more accurately determine drying times; this results in a more consistent product at the end of the process.
Overall drying times can be reduced when green sorting allows all of the fast-drying lumber pieces to be dried together, rather than being mixed with packs of slow-drying lumber.
Mills using the superior green density measurement technology of the LDS 200 have significantly lowered their average drying times, cut energy costs per kiln charge, and improved their grade recovery.