Rotor-pulsating apparatus for the preparation of liquid feeds on the grain basis

Abstract

In recent years, mass cultivation of microalgae has become widespread in order to use them in the national economy. In this plan, chlorella and spirulina are the most interesting. The influence of temperature on the growth of algae is due to the action on the enzyme system of culture. As the temperature increases, the rate of enzymatic reactions increases, which contributes to the formation of a significant amount of photosynthetic products. Depending on the optimum temperature of cultivation, the strains of microalgae are cryophilic, mesophilic and thermophilic. The most productive are thermophile strains. The issue of temperature regulation in plants for the cultivation of algae is devoted to a small number of works, and all of them, in general, relate to the development of design of heat exchangers of small volumes. The optimum parameters of the system of thermostabilization of the plant for growing microalgae can be determined from the equation of thermal balance, compiled for the most severe temperature conditions in the cultivating structure. Such conditions take place during the winter period of operation of the plant. To compile the equation of thermal balance, we assume the following assumptions: ♦ in the cultivator, the suspension of algae is well mixed and can be considered as an object with lumped parameters; ♦ the air heating system is executed in such a way that the heat source can be considered evenly distributed throughout the space of the cultivating structure; ♦ the dynamic properties of the object remain unchanged in time. As a result of the study, it was found that the overwhelming part of the air heating capacity goes to cover heat losses through the fence. In this case, the power of the system of thermostabilization with air heating is 4-5 times higher than when heated by means of a heat exchanger. Thus, thermostabilization of the suspension of microalgae with the help of air heating is undesirable, as it leads to significant losses of thermal energy. Keywords: cultivation of microalgae, energy losses, livestock waste