High-frequency moisture meters have been successfully used to measure the moisture content of a number of beneficiation products. However, when measuring the moisture content of bulk materials having low goodness-of-fit (e.g., metal-containing cakes), there are difficulties in developing circuits that allow measurement of the electrical capacitance of the material under low goodness-of-fit conditions ...

The electrophysical characteristics of beneficiation products arriving at mining and processing plants from different deposits tend to be heterogeneous ...

When operating technological systems associated with the use of air or gas flow (for example, systems for purification of industrial gases, pneumostransportation of bulk materials, artificial reduction of air humidity), there is a possibility of getting into the air line drops of liquid ...

Let at a distance d from a plane-parallel layer of thickness a with dielectric constant e a spherical conductor of radius g is placed, or a capacitor consisting of two such conductors located at a distance I from each other ...

Accuracy of measurements of the capacitive moisture-metric system essentially depends on the extent to which it is possible with its help to measure only the reactive component of the total conductivity of the controlled sample. ...

At open-pit mining method for transportation of rock mass at open pits of any productivity in recent years road transport is widely used, in particular, heavy-duty dump trucks. Dump trucks BelAZ-540, BelAZ-548A with carrying capacity, respectively, 27 and 40 tons are operated in conjunction with powerful excavators, have great maneuverability, good operational and speed qualities, low requirement for the profile of roads and 2-3 times increase the productivity of transport work in quarries. ...

The traditional approach to the study of sports technique is connected with instrumental methods of registration (kinography, cyclography, stroboscopy) of kinematic characteristics in order to reveal the kinematic structure, i.e. correlation of movements in time and space. ...

In a discrete moisture-metric system of F-meter type the whole set of measurements by the capacitive component is brought to the graduation temperature in accordance with the temperature coefficient of the capacitance of the measured material...

In resonant methods of moisture control, a capacitive sensor with the analysed material is in some cases included in the oscillating circuit of an autogenerator. ...

Changes in the conductivity of an electric circuit section are widely used for measuring ash content, moisture content, salt content and other parameters of solid, liquid and bulk materials; this allowed the practical realization of a number of measuring devices and systems that have found wide application in chemical, mining and metallurgical and other industries, as well as in energy and the practice of scientific research. ...

In the development of high-frequency continuous humidity control systems, efficient and reliable sensors are the most labor-intensive. Moisture sensors are usually in contact with bulk material or are in close proximity to it, exposed to vibrations, temperature effects, abrasion, environmental effects (dampness, dustiness, chemical activity), i.e. interfering factors that distort the information.

Numerous methods of measuring the moisture content of solid, liquid and bulk materials are known: conductometric, based on the use of the relationship between moisture and the active resistance of the material; capacitive - between moisture and dielectric constant (more precisely - apparent capacitance); neutron; nuclear magnetic resonance - yamr, etc.

The principle of autocompensation makes it possible to improve the accuracy of humidity control systems, which can be shown by analyzing such systems from the position of information theory. The average value of negentropy - the amount of information to obtain the ultimate accuracy of the measured quantity qo, calculated from the sensor current, is about 7 des. units. However, the sensor current contains not only useful information about the monitored humidity, but also interference (noise)...

На электрофизические свойства материалов влияют многие факторы: влажность, температура, гранулометрический и хи­мический составы и т. д. Поэтому полный дифференциал, например, объемного сопротивления селитры можно предста­вить в виде ...

The efficiency of processing of numerous types of mining-chemical and mining-metallurgical raw materials (coal, apatite, nepheline, phosphorite, sulfur, copper, iron, nickel ores, etc.) is significantly reduced in the absence of reliable and valid information on moisture content. Obtaining such information is associated with known difficulties, and to date the domestic industry has not carried out serial production of moisture-metric systems. Consider the possibility of building a moisture-metric system on the principle of phase separation of controlled and uncontrolled parameters.

Creation of the system for express discrete determinations of phosphate flour moisture content within 0-3,5% was preceded by the study of its electrophysical properties. For this purpose, the dependence lg r = F₁ (W) (g and W - respectively the volume resistivity and moisture content of phosphate flour) was obtained at direct current.

The rational method of measuring the moisture content of certain materials, the optimal operating frequency at which these measurements will be carried out, and hence the rational scheme of the measuring device can be outlined only by analyzing the frequency characteristics: ρ (ω) - resistivity; ε (ω) - dielectric permittivity; tgδ (ω) - loss angle of the controlled material. The applied methods of obtaining families of frequency characteristics at different moisture contents by broadband bridges with separate readout of active resistance g and apparent capacitance C (for example, bridge of E-10-2 type) are time-consuming and, as a rule, lead to significant errors associated with changes in the parameters of the wet material during the study. It is necessary, therefore, to reduce the time required to obtain the frequency characteristics so that the temporal instability of the material parameters can be neglected. It should also be borne in mind that the methods used involve a large number of individual measurements (several tens and even hundreds).