Accurate and fast moisture measurement

Döscher Microwave Systems is the competent partner for moisture measurement solutions in the timber industry. The measurement systems developed by Döscher work with microwave technology. A big advantage of this technology is that measurements can be carried out regardless of color changes in and the surface structure of the material. The microwaves penetrate several centimeters into the product. As a result, both the surface and core moisture are determined. Extremely accurate and long-time stable moisture measurement is guaranteed. Döscher uses robust sensors, which are not susceptible to soiling, and offers low-maintenance and durable products.

Numerous advantages

The devices prevent costly production downtimes and enable customers to achieve the desired product quality more quickly, while minimizing rejects. They also reduce costs related to complaints, optimize personnel deployment and reduce energy costs. Thanks to automated process control, i.e. reliable dryer control, companies from the timber industry which use microwave technology can also reduce their operating costs.

Different product lines

Döscher offers a wide range of different measuring devices, and customers always benefit from the optimal solution. The MoistureScan line was developed for the automatic moisture measurement of bulk materials. This line includes the MoistureScan, the MoistureScan XT and the MoistureScan EX. The MoistureScan XT is designed for extreme product temperatures and the reliable performance control of dryers, presses and roasters. The MoistureScan EX is suitable for potentially explosive areas.

The VenScan measuring systems are designed for band- and panel-shaped materials. This line includes the models VenScan (for materials with a maximum thickness of 10 mm), VenScan XL (for thicknesses of up to 40 mm), VenScan XXL (for materials with a maximum thickness of 100 mm), and the TriScan (measurement of the product in three places at the same time).

User-friendly solution

Users can track the measurement process on a monitor. Convenient and user-friendly software is available for the analysis of the obtained data. There are also a variety of interfaces for data transfer between the measurement system and the PC/PLC. In addition, Döscher Microwave Systems offers its customers online support.

Many customers in the timber industry

A reference project already reported on by the Holzkurier is the successful monitoring of the moisture content of wood chips and sawdust in Mercer International’s briquette production in Torgau, Saxony. Last year, a microwave measurement system from Döscher Microwave Systems was installed there. Mercer Torgau is enthusiastic about both the simplicity and the accuracy of the new measuring system. In fact, many measuring systems from Döscher Microwave Systems are in use at companies from the engineered wood industry.

Measuring the moisture of engineered wood

The accurate moisture measurement behind the fiber dryer is crucial for the entire further production process. Thanks to special developments, such as a reference resonator, measurements can now be carried out directly behind the dryer. No fiber collection mechanisms are necessary, since the fibers are measured directly in the product flow. The MoistureScan moisture measurement system is installed behind the fiber dryer. Explosion-proof models are also available.

To measure the moisture inside the fiber bin, for example in the belt scale or in the forming bin, the measuring heads of the MoistureScan are inserted laterally into wall of the bin. The moisture content of the fibers is continuously measured while they move past the measuring heads. Gaps in the fiber pile do not affect measurement accuracy because the MoistureScan system works independently of density.

The MoistureScan is ideally suited for process control along the forming belt. The physical measuring principle ensures that the water content of the press cake is not only measured on its surface but in the core as well. There are no distortions of the measurement results due to environmental influences, such as extraneous light, color changes in the product or fluctuations in its density. To ensure optimal interaction between the sensor and the product, the sensor moves over the cake on a carriage. This way, the surface of the press cake remains unaffected.

To determine the moisture content behind the chip dryer, Döscher Microwave Systems developed the MoistureScan XT. This system convinces with its high precision and long-time stability even at high temperatures up to 140°C and low humidity of 1 to 5%. Directly at the dryer outlet or inside a chute, a screw conveyor or storage containers – there are many places where the MoistureScan XT can be installed. Customers only have to make sure that the measuring heads are covered with the product.