As a means of converting abundant waste to wealth, thermal conversion of waste plastics of four different types (low and high density polyethylene (LDPE and HDPE), polypropylene (PP) and mixed plastics) was carried out in a batch reactor made of stainless steel at temperatures between 170 and 3000 0 C under atmospheric pressure. The vapor produced from melting the plastics was condensed to form the liquid hydrocarbon (fuel oil) product. Standards were followed for each of the waste plastics during the production process of the liquid fuel oil. The effect of reaction time and product yield were investigated. The physical properties measured include product density and specific gravity. The liquid products formed were characterized using FT-IR spectrometer (Spectrum 100 Perkin-Elmer). The heat combustion properties of the fuels produced were compared using ASTM D240. Also the API gravity and Sulphur content analysis were carried out using the ASTM D4052 and 4053 respectively. The chemical properties of the liquid product were compared for each of the samples and it was found that they vary from each waste plastic. Each of the liquid products contained low sulfur, but each of them varied from each other.

The immiscibility of vegetable oil in methanol provides a mass transfer challenge in the early stages of Transesterification reaction in the production of biodiesel. It is of a great significance to design high-performance nonlinear controllers for efficient control of these nonlinear processes to achieve closed-loop system's stability and high performance of a biodiesel CSTR. A mathematical model capable of predicting the performance and behaviour of a CSTR has been developed and evaluated. In this work, a comprehensive design procedures based on model predictive control (MPC) have been proposed to efficiently deal with the design of gain-scheduled controllers, controller tuning, optimal controllers and time-varying for nonlinear systems. Since all the design procedures proposed in this work rely strongly on the process model, the first difficulty addressed in this paper is the identification of a relatively simple model of the nonlinear processes under study. The second major difficulty is the analysis of stability and performance for such models using nonlinear control theory of a robust control approach. In the current work, the nonlinear model is approximated by a nominal linear model combined with a mathematical description of model error (due to nonlinearity) to be referred to (in this work) as model uncertainty. The robust control theoretical tools developed are used for the design of gain-scheduled Proportional-Integral-Differential (PID) control and gain-scheduled Model Predictive Control (MPC) in which the MPC method achieves the steady-state optimal set-points of the biodiesel Transesterification reactor.

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This article deals with the cleaning of generated gas for energy use in high-temperature fuel cells by the method of hightemperature adsorption in the potential utilization according to Industry 4.0. The study presents the methods of preparation of a wide range of sorbents, test equipment, used analytical methods and overview of achieved results. This project focused on high-temperature removal of acidic components such as hydrogen sulfide, Carbonyl sulfide, hydrogen chloride and hydrogen floride (H2S, COS, HCl and HF), using laboratory-made or commercial sorbents, from the gas resulting from the gasification of biomass. In the theoretical part of the biomass and its gasification, cleaning possibilities of the raw gas and, above all, of selecting a suitable adsorbent for high-temperature removal of unwanted components was the major focus. The possibilities of using purified gas in fuel were also mentioned in the article and the properties and structure of the fuel cell. The experimental part of the project addressed the testing of specific adsorbents at different temperatures. The task was to find a sorbent that would clean the raw gas at the specified temperature to the desired concentrations of undesirable components in order to enter as fuel into a high-temperature fuel cell. Commercial and naturally obtained dolomite were modified and tested. The effective time range of sorbents at atmospheric pressure (101.325 kPa) and at different temperatures ranging from 300 to 600 °C were also measured. From the results obtained, modified dolomite was established to be more effective adsorbent for the removal of hydrogen sulphide gas from syngas produced from biomass.

This paper describes the strategy to design and modify a conventional controller by direct synthesis and the internal model control (IMC) methods for a single-input, single-output (SISO) process system. Both of these methods are the most widely used approaches, both in their simplicity and in their generality. The design of a direct synthesis controller based on a linear inversion of the non-linear process model about a steady-state was first considered. The particular linear design technique adopted resulted in a Proportional -Integral (PI) controller whose parameters are easily computed as a function of the parameters of the linear invertible model and the controller tuning parameter. The internal model control (IMC) methods were also considered to determine the fault from external disturbance. From this study, it was observed that under certain conditions both direct synthesis and internal model control methods are equal. Their use in the design of analog and digital controllers is presented by the method of the required model.