Study On Operation Optimization Of 600MW Direct Air Cooled Unit

Thermal power plant is a large primary energy-consuming industry. The in-depth study of the operating characteristics and economy improvement of the thermal power plant process has an important significance for enhancing the competitiveness of the thermal power plant. Meanwhile, it also has great strategic significance to the economic and social sustainable development. Therefore, a combination of theoretical and experimental analysis methods were used to study the operating characteristics of 600MW direct air cooled unit in this paper.First of all, from the definition formula of the steam turbine unit efficiency the equations of power variation to the main steam parameters have been derivated according to the relationship between the general principle of turbine off-design condition and variable parameter, and through variable backpressure economic test the impact of back pressure on the economy was studied quantitatively.The abnormal changes which appeared in the turbine single valve switching sequence valve operation was improved through the investigation and study of a large number of steam turbine units distribution optimization and the test of sequence valve. The steam turbine distribution optimization program changed the valve sequence from 3+4â†'1â†'2 to 3+4â†'2â†'1. The governing valve characteristic curve and the degree of overlap were also modified in this paper.Then the reasons of winter freezing of direct air cooling unit condenser was analyzed and the anti freezing measures was proposed to overcome these problems, in addition, the back pressure optimizing operation mode in winter and summer was obtained according to the variable back pressure test; the reform plan was proposed for the fast pollution characteristic of air cooled island, which brought considerable economic benefits for the company; then the power consumption model of air cooling fan was proposed, and through the economic test of air cooling fan the economy operation mode was obtained; technological transformation program was put forward due to the big deviation of hot well water level, which is successful improved the operation of hot well.Finally, in order to overcome the drawback of only one unit sliding pressure curve, the sliding pressure curve clusters was obtained according to variable back pressure test, which improved the efficiency of the unit. In order to automatically select corresponding sliding pressure operation according to the actual back pressure curve, sliding pressure operation control logicwas revised thermal and technical personnel in unit of Jinglong Power Plant. Meanwhile, the main functions of SIS were improved and its range of applications were expanded.