A Discrete Optimized Model for the Monobloc Configured Circulating Water System of a Thermal Power Plant and Its applications

A discrete optimized model was proposed for a monobloc configured circulating water system featuring non-continuous change of water flow rate. By conducting iterative calculations of equivalent profit points the model can determine the critical operating conditions at the juncture of switch-over of circulating-water pumps. With the power unit No.7 of the Huangtai Power Station serving as an example the present model was used to study operation optimization in order to determine the most economical grouping-mode of operation for the circulating water pumps at different seasons and at various loads of the power unit. A profit analysis indicates that for a 300 MW power unit through the introduction of discrete optimization for a circulating water system it is possible to achieve a reduction of coal consumption by 0.5 - 0.7 g (kWh). On the basis of thermodynamic test data an empiric formula is determined for the heat transfer factor of a steam condenser, which can serve as a guide for other similar units.