Optimization and designing of a fluidized bed thermal power plant with low quality lignite

Fossil-fueled electricity generation plants are still important in world primary energy consumption. Among fossil fuels, the use of coal is remarkable. As a domestic resource, coal-fired power plants are important for our country. Some of the pulverized combustion power plants in our country use low quality lignite with high ash, moisture and silica content. Therefore, the operation of the domestic fuel-based thermal power plants in our country is quite difficult and generation losses and yield losses due to different reasons occur. When selecting the combustion system, boiler combustion chamber temperature, ash melting temperature and ash and moisture content of coal should be taken into account. The most suitable technology to burn non-standard low quality fuels directly to full combustion conditions and because of their internal SO2, NOx emission retention properties is generally fluidized bed, especially dolaşımlı akışkan yatak (DAY) combustion technology. In this study, before designing a fluidized bed thermal power plant with low quality lignite; elemental and short analyzes of samples taken from coals in Seyitömer and Tunçbilek region of Kütahya province, ash melting, boiler drum water, feed water and condensed water were analyzed. Using the energy conversion design/modeling software Thermoflex, two different power generation plants were modeled as Seyitömer region's low quality lignite fueled pulverized and fluidized bed system. As the fuel value used in the modeled thermal power plants; three samples taken from Kütahya region were analyzed and the values obtained were averaged. Average analysis values of low quality lignite coal used in design; its thermal value is 1793 kcal / kg, the moisture content is 37.78% and the ash content is 28.36%. As a result of the design, the modeling outputs were compared, sensitivity analyzes were carried out for five different case conditions for the fluidized bed power plant with high system efficiency and lower emission values and the results were evaluated.