2results about "Water circulation" patented technology

This utility model discloses a warm-up system for an internal circulation pump in a natural circulation boiler, belonging to the technical field of boiler auxiliary equipment. It includes an internal circulation pump, a pre-pump pipeline and a post-pump pipeline respectively equipped with a first valve and a second valve connecting the downcomer to the economizer, a third valve connecting the lower part of the downcomer to the economizer inlet via a pipeline, a warm-up connection pipeline connecting the upstream of the second valve and the upstream of the third valve, and a flow meter, a fourth valve, and a regulating valve arranged sequentially. When the internal circulation pump is in standby mode, the first valve is kept open and the third valve closed, the fourth valve is opened, the electric regulating valve is opened, and the second valve is closed. The working fluid in the downcomer bypasses the pump through the pre-pump pipeline, the internal circulation pump, the post-pump pipeline, the warm-up connection pipeline, and the economizer recirculation pipeline, forming a closed natural circulation loop with the boiler evaporation system. This keeps the pump body hot and at the same temperature as the working fluid during standby. This system is mainly used in natural circulation boilers to maintain the internal circulation pump in a hot standby state, eliminating the risk of thermal shock during pump start-up.

The present application relates to the field of energy saving and control technology of thermal power generation, in particular to a low-pressure heater drain system load control method for thermal power generating units and related equipment, real-time monitoring of the load of the thermal power generating unit, selection of a target drain control mode according to a preset load interval, wherein the first load interval corresponds to the first control mode, the second load interval corresponds to the second control mode, both have different control targets and logic, and the maximum value of the first interval is less than or equal to the minimum value of the second interval; the target mode control logic is executed to regulate the operating state of the drain system. Through load interval division and mode dynamic switching, the scheme realizes the reduction of energy consumption of the drain system, the reduction of system vibration frequency, achieves self-adaptive regulation and control of the drain system under all working conditions, and improves the operating efficiency and stability.