Energy Cascade Utilization And Characteristic Analysis Of 600MW Supercritical Heating Unit

There is a large amount of cold source loss in the condenser of the conventional cogeneration unit.The lost heat is taken away by the circulating cooling water of the power plant and is wasted in vain,which does not conform to the idea of energy saving.In recent years,the absorption heat pump technology has become more and more mature,and its application to the combined heat and power unit can effectively recover the waste heat in the circulating cooling water of the power plant.Considering that the absorption heat pump does not require driving steam of high quality,a screw expander can be introduced to use the extracting steam of the heat supply unit for the first time.Therefore,a heat supply unit transformation plan that couples the absorption heat pump and the screw expander is formed to realize the goal of energy cascade utilization,energy saving and consumption reduction.After determining the equipment required for the transformation of the heating unit,this paper establishes a mathematical model corresponding to the key equipment,and completes the specific equipment selection.In order to be able to evaluate the thermal performance and economy of the heating unit,evaluation indicators are given.Then use these evaluation indicators to compare the traditional extraction heat supply unit and the reformed heat supply unit,and the results prove that the thermal performance of the heat supply unit is effectively improved after the heat supply unit is reformed.For example,when the heat supply load increases,the standard coal consumption rate for power generation decreases considerably.With the same heat load,the extraction steam of the heating unit can be significantly reduced.In addition,the transformation of the heating unit can bring more electricity and heating price income,which is more environmentally friendly.At the same time,the energy flow diagrams before and after the transformation of the heating unit are respectively given,which intuitively reflects the location and proportion of energy loss.The peak shaving capacity of the two heating units was also compared and found to be slightly improved.Then with the help of the Ebsilon platform,the multi-condition calculation of the reformed heating unit is carried out,and the influencing factors of the overall thermal performance of the absorption heat pump and the reformed heating unit are respectively studied.The calculation results can guide the change of the unit parameters to improve its thermal performance and economy.Using Meteonorm7.0 software to call up the local solar radiation data map of the heating unit,and analyze the actual situation.In order to further improving the heating unit plan,it was decided to introduce solar energy concentrating heat collection device and heat storage device into the original plan to form the coal-fired solar heating unit scheme.The effective use of solar energy in the system can reduce the coal consumption of thermal power plants to a certain extent and help improve the environment.