The dissertation is devoted to solving of the scientific and applied problem of increasing the intensity and energy efficiency of drying seeds of cereals, oilseeds, vegetables and technical crops with the preservation of high similarity of the sowing material.
The problem is solved by determining the optimal drying regimes of seeds of cereals, oilseeds, vegetables and technical crops and the development of energy-saving heat technology drying with the use of heat pumps for the purpose to preservation high quality properties of material.
For the first time, stepped drying regimes for seeds of cereals, oilseeds, vegetables and industrial crops have been developed, which allowed to obtain a similarity of seed material 98 - 100%, with a reduction in the drying time of 1.7 - 3.4 times and energy consumption by 62%.
The dissertation presents the results of experimental and theoretical studies of the basic laws of drying seeds of cereals, oilseeds, vegetables and technical crops; the mathematical model of the process is formulated and the rational parameters of drying are determined, researches of heat-mass-exchange processes are carried out, energy-efficient drying regimes, new heat engineering and equipment with the use of heat pumps are developed.
On the basis of the complex research carried out on the convective drying stand, an engineering nomogram for determining the permissible temperature of heating of seeds of grain crops was developed from experimental studies of kinetics of the process and qualitative characteristics of the material.
According to the results of experimental research, drying stands with a heat pump are made and energy-efficient drying regimes with a high similarity of grain seeds, oilseeds, vegetables and industrial crops was tested.
Energy-efficient drying modes have been developed using heat pumps for drying seeds of cereals, oilseeds, vegetables and industrial crops, in particular for drying pumpkin seeds, a drying regime of 60/40°C was used. Consumption of heat is lower than the standard values for seed grain by 40%. High seed germination is ensured at 100% level.
Calculations of specific heat consumption during drying of seed material in a heat pump are 3675 - 3700 kJ / kg of evaporated moisture.
The heat engineering scheme of the five-zone mining grains of continuous action with the productivity of 15.5 t/h is developed. for the drying of seeds of cereals, oil and technical crops using the heat pump and the gas engine of the generator DvGA-315. The energy efficiency of the drying process of seed material is ensured by the distribution of flows of the generated thermal energy of the gas engine of the generator and directed into the 1,3,4 zone of drying of the grain dryer from the application of stepped drying modes.
The calculated specific heat consumption is 3024 kJ/kg of power moisture, expected economic effect from the implementation of 858127 UAH, with a period of payback of capital investments 5.5 years.
For the production of vegetable seeds, 3 energy-efficient non-waste technologies for the processing of tomatoes, pumpkin and pepper from the installation of heat pumps have been developed. The cost of seeds of vegetable crops is most influenced by the cost of fuel and raw materials, as well as the wages of employees. Cost reduction is possible due to the use of energy-efficient drying modes with heat pumps and the use of waste products.
