Research On Energy Consumption Characteristics Of Regenerative System In Large Scale Coal-fired Units

China’s power generation is based on coal, while coal resources being nervous, so the primary task of our national thermal power unit is to reduce the coal consumption of the units. The feed-water regenerative system is an important part of the unit. Optimizing and improving facilities in the regenerative system can raise the overall economy of the unit. It is necessary to analyze the energy consumption characteristics of generative system, and make some adjustment. This paper is based on the national "973" project, researching on large coal-fired units, and the main researching includes:Firstly, researching on a600MW unit, according to the heat transfer knowledge, establish heat-exchange model inside the heat exchanger, then calculate temperature difference of the heat exchanger as it should being under different load. And according to the mathematics knowledge, deduce the temperature curves of feed water and steam inside the heater. Based on consumption analysis theory, calculate specific consumption distribution of the various heat-exchange parts inside heater under different load.Secondly, steel price and coal prices in recent years have different amplitude increase, and the re is a big difference of coal prices in vary area, but the temperature difference of heat exchanger is still designed used old standards. Researching on a600MW unit, as units capacity increasing, it is necessary to discuss whether the current design standards are the best. We should get the conclusion of best temperature different corressponding to the range of coal prices and steel price. And calculate the eventurally profit as20years service life.At last, researching on a1000MW ultra-super critical unit, we can add some steam heat exchanger to raise temperature of feed water, to make full use of high quality overheating steam and to reduce heat consumption coal consumption while improving the unit efficiency because of unit capacity increasing and steam extraction parameter raising especially the steam extraction temperature being very high after reheating.