Establishment of regularities of biochemical transformations in grape berries during refrigerated storage with preliminary thermal treatment

Kazimova I., Mikayilov V., Omarova E., Gasimova A., Nabiyev A.

TECHNOLOGY AUDIT AND PRODUCTION RESERVES, vol.1, pp.31-38, 2025 (Peer-Reviewed Journal)

Qısa məlumat

The object of research is the process of enrichment of magnetite suspensions

in screw separators, taking into account the particle size distribution,

the compressibility of the liquid in the interparticle space, and the shape of

the particles, which allows to assess the influence of these factors on the value

of the effective viscosity of the suspension. The viscosity of the suspension

is one of the properties for ore suspensions with a wide range of particle

sizes and different concentrations of solids in operations and products. It

determines the nature of the movement of the liquid, the state of the solids

in it – the degree of its loosening, the difficulty of sedimentation, and energy

consumption for transportation during the enrichment of magnetite ores in

screw separators. The studies were conducted using analytical and experimental

methods. It was experimentally established that the dependence of

the viscosity of the pulp suspension on the particle size in the range of less

than 1 mm has an inversely proportional relationship. At a volume concentration

of solids in the pulp from 10 to 70 %, the viscosity of the suspension

increases with a decrease in the volume concentration of the minus 0.1 mm

class from 100 to 20 %. It has been established that at temperature regimes

from 28 to 50 °C, the viscosity of magnetite suspensions increases with a

decrease in the grinding fineness in different ways. The viscosity of magnetite

suspensions depends on the mass fraction of solids: material with a fineness

of 80 % minus 0.044 mm increases the viscosity of the suspension at concentrations

above 40 %, and at a fineness of 80 % minus 0.031 mm – above 60 %.

The obtained scientific result, in the form of a calculation of the effective

viscosity of the pulp, is based on a theory that takes into account the influence

of particle size as a function of their average effective diameter, concentration

and shape of suspended particles. From a practical point of view, the research

results allow to develop optimal conditions for gravitational enrichment of

magnetite ores in screw separators and avoid additional losses of valuable

components.