Development of an algorithm for optimization of continuous technological process of cultivation of microorganisms

Abstract

When implementing the tasks of controlling technological processes, finding the optimal control actions, and creating control algorithms that implement the optimal modes of technological processes, it is necessary to present the criterion of optimality in the form of a goal function, the extremum of which best meets the purpose of this object and expressed as - Relevant technical and economic indicators. The criterion of optimality should be an integral indicator that reflects the main aspects of production. Profit is most often taken as such a criterion for typical microbiological industries - as the most generalized indicator, reflecting almost all aspects of the enterprise. Possible criteria of optimality are analyzed in the form of technical and economic indicators of the process of cultivation of microorganisms, the extremum of which best meets the objectives of production and reflects the main aspects of the functioning of the control object. The analysis of possible modes of microalgae cultivation has been carried out. Two optimization algorithms are substantiated. The first one is based on random search method with an absolute bias, an algorithm for optimizing the process of cultivating microorganisms with continuous regeneration of the flow in one cultivator. The second is an algorithm for determining the optimal residence time of chlorella particles in multistage cultivators, focused on the method of dynamic programming implemented in Wellman's recurrence relation. The developed algorithm for operational forecasting and automatic control of the chlorella cultivation process allows, under given production conditions and the composition of nutrients, to increase the productivity of technological equipment and improve the quality of the target product, as well as to prevent in advance various unforeseen and emergency production situations.

Implementation of mathematical models and algorithms in task control of the microalgae cultivation processes

“…The process engineer can construct a comprehensive model of the photobioreactor (PBR) and the culture under autotrophic, mixotrophic, or heterotrophic conditions in order to address optimization and scale-up problems by having knowledge of microalgae kinetics and physiology. The use of modeling methods and optimal control algorithms contributes to a scientifically based choice that is effective in presenting information, substantiating the composition and structure of technical means [1,2]. Automatic control of the quality and composition of nutrients at the inlet, as well as control of the process's output indicators, is one of the necessary conditions for the optimal operation of the microorganism cultivation process.…”