Experimental investigation of energetic and exergetic performances of a biomass power plant using wheat residue under different operating conditions

This thesis investigates the thermodynamic performance of a wheat straw-fired biomass power plant located in Tokat province under two different operating conditions using experimental data. The examined conditions represent the plant's pre-revision (deaerator heated from the boiler) and post-revision (deaerator heated from turbine extraction) operating regimes. The main objective of the study is to comparatively reveal the effect of the revision implemented at the plant on system efficiency through energy and exergy analyses. In the pre-revision condition, the fuel consumption rate was 7.842 tons/hour, with thermal efficiency calculated as 21.45% and exergetic efficiency as 20.43%. The fact that exergetic efficiency is lower than thermal efficiency stems from the chemical exergy of biomass fuel being higher than its heating value, which is a thermodynamically expected result. A revision was implemented in the deaerator heating method to improve system efficiency. Following the revision, fuel consumption decreased to 7.156 tons/hour, while net power output increased from 6500 kW to 6550 kW. Thermal efficiency increased from 21.45% to 23.68%, and exergetic efficiency increased from 20.43% to 22.56%. Fuel consumption was reduced by 8.75%. In conclusion, this study demonstrates the importance of system integration and heat recovery strategies in improving efficiency in biomass power plants. The performance improvement achieved through a simple modification in the deaerator heating method presents a practical solution applicable to similar power plants.