Author, Institution: Andrius Laučka, Kaunas University of Technology
Science area, field of science: Technological Sciences, Electrical and Electronics Engineering, T001
Scientific Supervisor: Prof. Dr. Darius Andriukaitis (Kaunas University of Technology, Technological Sciences, Electrical and Electronics Engineering, T001)
Dissertation Defence Board of Electrical and Electronics Engineering Science Field:
Prof. Dr. Liudas Mažeika (Kaunas University of Technology, Technological Sciences, Electrical and Electronics Engineering, T001) – chairman
Prof. Habil. Dr. Arūnas Lukoševičius (Kaunas University of Technology, Technological Sciences, Electrical and Electronics Engineering, T001)
Prof. Dr. Jurij Novickij (Vilnius Gediminas Technical University, Technological Sciences, Electrical and Electronics Engineering, T001)
Prof. Habil. Dr. Krzysztof Okarma (West Pomeranian University of Technology in Szczecin, Poland, Technological Sciences, Electrical and Electronics Engineering, T001)
Prof. Dr. Vidas Raudonis (Kaunas University of Technology, Technological Sciences, Informatics Engineering, T007)
The dissertation defence takes place online.
The doctoral dissertation is available on the internet and at the library of Kaunas University of Technology (K. Donelaičio g. 20, Kaunas).
The fertilizers are widely used in farming, which when injected into soil, enhances the growth and development of plants. The main chemical substances used in the production of fertilizers are usually in powder form. The chemical reactions used in manufacturing process allow to produce pellets. This allows to prevent segregation, and therefore, cultivated land is evenly fertilized with different substances.
One of the most common methods of producing carbamide, ammonium nitrate fertilizers is based on cooling of product using airflow. Prilling is considered to be the best way of forming equal spherical particles from solutions and suspensions. Prilling equipment, used for production, inevitably becomes clogged up, and it mainly depends on chemical components and additives of pellets. Short-term and long-term cleaning of equipment is necessary. Timely stopping of production line means less losses because of lower quantity of reprocessed production, less wasted energy producing low quality product and lower general contamination of equipment, when contamination is identified earlier.
The thesis presents measuring results related to the determination of connection between clogging up of granule formation equipment, and their quantitative, qualitative parameters are presented. Unrelated parameters are rejected by assessing the changes in pellets size and quantity, while values that are related to changes are used for the conclusion of the fuzzy logic model.
Also, the thesis provides the assessment of connection between results received by using contactless measuring of pellets and contamination of granulation equipment. The reliability of the contamination identification type system based on fuzzy logic is evaluated. Such reliability facilitates the objective assessment of the state of contamination of the production line.