External heat-and-mass transfer during filtration drying of packed birch peeled veneer has been investigated. The dependence of heat-and-mass transfer coefficients on actual speed of heat agent filtration has been determined for dry and wet veneer sheets. The effect of heat agent temperature on the values of diffusive, heat and hydrodynamic boundary layers, and as a result, on heat-and-mass transfer intensity has been established by the experiments during filtration drying of packed veneer.

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The experimental studies of hydrodynamics of the gas flow filtration through the candied fruits layer, formed by the different methods, were carried out. The particles of studied candied fruits were cylindrical, equally sized, filled the whole container for drying. The main characteristics of the layers were experimentally determined: porosity, equivalent diameter, specific surface. The results of experiments prove the expedience of the candied fruits layer formation of the cylindrical particles with correct form by the method of placing candied fruits vertically “with overlap of channels”. Such method allows provide the insignificant hydraulic resistance of the layer and rather high speed of the gas flow filtration through this layer. It will result in the increase of heat transfer and mass output coefficients, so to the intensification of filtration drying. Such formation method also allows reduce the volume of drying equipment, shorten the time of drying and decrease the energy consumption of process.

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In the list of environmental pollutants, mercury is one of the first places. It is mercury, its inorganic and especially organic compounds belong to extremely toxic substances of the first class of danger.Mercury has been known since ancient times, it is mentioned in the writings of Aristotle, Theophrastus, Pliny the Elder, Vitruvius and other ancient scholars. The Latin name for this metal is “Hydrargium”, given to mercury by Greek physician Dioscorides (1st century B.C.), means in translation “silver water”. The most important and ancient in Ukraine is the Mykytiv mercury deposit, which was opened in 1879. and operated since 1885. Production of mercury until 1914 was 300–400 t/year (most of it was exported). After the revolution and the war it was slowly recovered (127 tons in 1926), in 1935–1940 it is annually brought to about 300 tons. After the Second World War, the Mykytiv deposit was built. Discovered in it reserves (up to a depth of 300 m) were evaluated in 6.000 tons in 1927, after deep drilling was introduced in the 1960s. they have increased slightly. In the world economy, mercury is widely used in the electrical engineering and instrument industry, laboratory and medical practice, in the production of chlorine/alkali, in agriculture (included in fertilizers), in small-scale mining of gold and silver and other fields. No other chemical element belonging to the first class of danger has such wide use in production processes, products, substances and such multivariate penetration into the organism (with air, food, water, through the skin) as mercury and its compounds. The main source of mercury poisoning is mercury vapor and dust of mercury compounds. The toxicity of metallic mercury is due to the fact that while inhaling its vapors more than 80 % of the mercury is absorbed by the brain, kidneys and other internal organs, leading to he devastating consequences primarily on the central nervous system and kidneys. Mercury semi withdrawal period from humans is from 35 to 96 days. The average semi withdrawal period from the blood is 65 days, from hair 72 days, in total from the organism - 76 days. A longer semi withdrawal period of mercury from the brain than from other organs has been recorded in experimental animal searches. In humans, high levels of mercury in brain tissue were detected 10 years after it ceased contact with a toxic substance. Mercury poisoning can be acute or chronic. In everyday life, most often find the second option.