Principles and Applications of Microwave Moisture Analyzers

A microwave moisture analyzer measures the moisture of a substance at microwave frequencies. It consists mainly of a microwaveoscillator and a microwave attenuator, and is used mainly for measuring moisture in soil, cement, walls, and other building materials, as well as in paper, wood, feed, grain, coal, and similar materials.

Principle of the Microwave Moisture Analyzer:

Microwaves are high-frequency electromagnetic waves. The attenuation and phase shift produced when microwaves pass through a medium are determined mainly by the medium's dielectric constant and dielectric loss tangent. Water is a polar molecule whose dielectric constant and loss tangent are far higher than those of ordinary media. Under normal conditions, the dielectric constant and loss tangent of a moist medium are determined mainly by its moisture content. The microwave energy is emitted from below the conveyor belt by theUMmicrowave moisture analyzerC's C-shaped frame lower arm, passes through the belt and material, and is received by the microwave receiver on the CC-shaped frame upper arm above the belt. From the attenuation of microwave power and the change in phase shift, the moisture content of the material can be calculated.

Applications of the Microwave Moisture Analyzer:

Applied to measuring instruments, this technology has produced the online microwave moisture analyzer. Compared with traditional infrared technology and infrared instruments, its advantages are obvious. When testing pulverized coal, for example, an infrared instrument's detection range is very limited, whereas microwaves penetrate and detect all of the coal, ensuring reliable detection of the moisture content of almost any solid. It is a highly reliable non-contact moisture tester—rugged, fast-responding, and accurate—designed for continuous in-process moisture measurement. Another key feature of the online microwave moisture analyzer is the choice of transmission or reflection measurement mode.

Microwave moisture analyzers are widely used for coal, sintered (pelletized) mixes, iron ore, chemicals, bauxite, nickel ore, sugar, tobacco, bagasse, grain, silica, wood, wool, food, sand, polymers, cotton, and other non-conductive materials.