EVAPORATOR SYSTEM FOR INCREASING THE CONCENTRATIONOF FEEDING LIQUOR
Nowadays, there is a steady growth in the production of animal feed, poultry and fish all over the world. Humic preparations are widely used in feedstuff. At the moment, there is a lot of experience in using humic drugs to: accelerate the growth and development of animals; reduce morbidity; increase the body's resistance to adverse environmental conditions. Humic substances are characterized by a stimulating effect at the cellular and subcellular levels. The equipment used for the production of humic preparations has a number of disadvantages: complex; expensive; negatively affects humic preparations, reducing their quality; occupies a large area with low productivity and high labor costs. Currently, the development and justification of the parameters of equipment for the production of humic preparations is relevant. The purpose of the study is to establish the relationship between the design parameters of the ejector and the performance of a vacuum evaporator to increase the concentration of feed suspensions using the example of a humic suspension. Methodology is calculation and experimental determination of the design parameters of the ejector and the time of pressure reduction in the boiler of the evaporator plant from atmospheric to working. Results. Under the condition of ensuring the maximum volumetric injection coefficient, dependences were obtained to determine the diameters of the working nozzle and the mixing chamber of the ejector. In the range of operating the absolute pressure in the boiler of a vacuum evaporator of 20...28 kPa, it is rational to provide water pressure in front of the working nozzle of 250...350 kPa with a ratio of the cross section of the mixing chamber and the working nozzle of 4...6, and the rate of water outflow from the working nozzle - 20…25 m/s. At a pressure after the ejector = 110 kPa and a diameter of the working nozzle of 5 mm, the time for lowering the pressure in the boiler from atmospheric to working is 181 s, with a diameter of the working nozzle of 10 mm, the time for lowering the pressure is 45 s. The results of time calculations are confirmed by experiment and are used in determining the performance of a vacuum evaporator. The results of the study can be used to increase the concentration of liquid feed additives. Scientific novelty. The mathematical model has been developed to simulate the operation of a vacuum evaporator with an ejector to increase the concentration of feed suspensions. The model has been obtained for calculating the time of pressure drop in the boiler during the start-up of a vacuum evaporator, taking into account: Ww is the total volume of air in the evaporator above the suspension, steam condenser, condensate collector and pipelines connecting them, m3; Pр - water pressure in front of the working nozzle, Pa; Pn is the pressure of injected air, Pa; ρn - initial air density, kg/m3; Pс - pressure after the ejector, Pa; Pnр - saturated steam pressure, Pa; tr is the working water temperature, ºС; tn is the temperature of the injected air, ºС; Gn is the mass flow rate of injected moist air, kg/h.