Energy Saving Research Of Cogeneration Based On The Absorption Heat Pump System

Thermal power plants play an important role in the process of national energy saving. with the scientific and technological advances, the heating units have become more and more larger, heating technology model have also more and more diverser. Extraction condensing unit coupled with absorption heat pump(AHP) heating mode can be further recycled water heat, which traditional extraction condensing heating mode waste in the condenser. AHP heating mode increase the supply of heat without expanding the size of the unite and improve the energy efficiency. Extraction condensing unit coupled with absorption heat pump(AHP)as well as traditional extraction condensing heating mode had to extract steam from the communicating pipe between intermediate pressure (IP) and low pressure (LP) cylinders in cogeneration. AHP and the extraction condensing heating mode need different grade of extraction pressure and extraction capacity at the same heat load, so the reasonable application conditions of these two heating systems was of great significance to improve the performance of large-scale cogeneration units.Firstly, This paper build first class lithium bromide absorption heat pump(AHP),600MW power plant system on Ebsilon software platform, and the actual data test their validity and applicability of the model, secondly, The paper also analyze the heat economy of the AHP and extraction condensing heating mode and defined the concept of equivalent extraction pressure (EEP), The paper revealed the variation between the COP of single effect lithium bromide of AHP and the heat source of pressure under the same return water temperature under the temperature rise of the heating network conditions. Base on the case of300MW and200MW air-cooling units, the calculation showed that the AHP heating mode is better than the extraction condensing mode when the turbine low pressure communicating tube sub-cylinder pressure at0.4to1.0MPa, which300MW units allways are. Otherwise, the traditional extraction condensing heating mode of200MW unit is better. The studies have shown that:The equivalent extraction pressure(EEP) can determine the economics of different heating modes, so as to provide a reference for the unit of heating retrofitted mode.