mass transfer

Розглянуто фрактальну модель тепло- та масоперенесення у капілярно-пористих матеріалах, що описується системою диференціальних рівнянь у частинних похідних з дробовим порядком. Різницевим методом отримано числовий розв’язок задачі для різних значень дробової похідної.

There was considered fractal model of heat and mass transfer in capillary-porous materials which is described by the system of differential equations in partial derivatives with fractional order. The difference method receives the numerical decision of a problem at various orders of a fractional derivative.

The dissolution process of potassium chloride particles in the apparatus with two-blade mechanical stirrer was investigated and the mass transfer coefficient was determined. The experimental results were generalized by criterion dependence. The independence of the mass transfer coefficient from the solid particles diameter was confirmed. A countercurrent process of potassium salt dissolution in two apparatuses with a mechanical stirring was considered. A mathematical model for countercurrent dissolution was developed and the efficiency of this process was determined.

The mathematical solution for determining the contraction stresses in the cementconcrete or other cemented layers of road clothing is proposed in the article.

Extraction of glucomannan from crude porang flour by acid hydrolysis and ethanol precipitation was studied. Effects of acid concentration, temperatures and time were investigated, kinetics model of the process was developed and the parameters were evaluated based on experimental data. New data on yield and purity of glucomannan under various conditions were obtained.

This paper is devoted to the method of extraction unit calculation of periodical action for direct flow and return flow of extraction processes based on an analysis of the kinetics of extraction of components of the porous structures of minerals and seeds plant material under a constant driving force. Запропонована методика розрахунку прямотечійного та протитечійного екстракторів безперервної дії на основі аналізу кінетики екстрагування цільових компонентів з пористих структур мінеральної сировини та насіння рослинної сировини в умовах постійної рушійної сили. 

A new experimental-computational method for designing the catalytic converters for gases purification contaminated with hydrocarbons based on researched mechanism of heterogeneous catalytic process which stages are described by mathematical models is developed.

We present results of development of mathematical models of external mass exchange in extraction of desired products from vegetable raw materials and mathematical models for the determination of the minimum time of achievement of the equilibrium state of the system and the current concentration of a soluble substance for their using in the optimization of operation of solid-phase extraction equipment.

Experimental and analytical investigations of mass exchange during dispersed materials encapsulating in quasi-liquefaction state are presented. The mass transfer coefficients during encapsulating have been determined for different dispersed materials depending on air rate.