Modelling of Energy Production from Alternative Fuels
School of Science and Technology, MSc in Energy Systems
In the thesis, a Fluidized Bed Combustion Boiler Combined Heat and Power (CHP) plant for energy recovery from the Municipal Solid Wastes (MSW) for the city of Thessaloniki, modelled through the use of the COCO simulation software, is presented.
Initially, the amount of MSW land disposal in the city of Thessaloniki is taken into consideration, regarding data from literature, in order for the annual biodegradable fraction of MSW to be estimated.
Subsequently, a detailed research on the optimum Combined Heat and Power (CHP) facility between three cases of three different pressure types of boiler, is developed. Assuming that the biodegradable fraction of MSW would be separated before incineration process, and considering the probable amount of that fraction as well as its chemical composition and moisture content, a CHP plant model was constructed for each case, through COCO and the total amount of electrical and thermal energy that could be generated was estimated. The boilers pressures selected to be studied are 2MPa, 5MPa and 10MPa. Εach potential CHP plant consists of a high and a low pressure turbine, a condenser and a low pressure pump. Simulation models for these different cases have been developed and validated against available experimental data.
The COCO results indicated similar total CHP efficiency of around 90% in all three cases, while the power extracted could cover an average of about 15% of the city’s total energy needs. A significant difference between these cases was detected in the thermal and electrical energy production, separately. The first case provides higher amount of thermal energy and covers thermal energy needs of 9.26% more than these of the third case. However, the latter covers the electrical energy needs of 29.3% more than the former, while in total energy needs it overweighs for almost 2%.