Steam flow injected wide-range condensing type 600MW unit heat supply system and heat supply method

Abstract

The invention relates to a steam flow injected wide-range condensing type 600MW unit heat supply system and a heat supply method. Along with the increase of the heating area of urban and rural buildings in northern areas of China and the relevant requirements of national energy conservation and environmental protection, a large number of water heaters and small thermal power generating units are shut down in succession, and large thermal power generating units gradually become main heat sources for centralized heating of northern cities and towns of China. The steam flow injected wide-range condensing type 600MW unit heat supply system comprises a Laval sprayer nozzle (1), a low-pressure cylinder A (2) and a low-pressure cylinder B (3), wherein one end of the low-pressure cylinder A and one end of the low-pressure cylinder B are connected to one end of a sprayer nozzle outlet door (5) through a low-pressure steam pipeline (4), the other end of the sprayer nozzle outlet door is connected to the Laval sprayer nozzle, the other end of the low-pressure cylinder A and the other end of the low-pressure cylinder B are connected to a medium-pressure cylinder (7) and a sprayer pipe inlet door (8) respectively through a medium-low pressure communicating pipe (6), and the sprayer pipe inlet door is connected to a Laval sprayer pipe through a driving steam pipeline (9). The steam flow injected wide-range condensing type 600MW unit heat supply system and the heat supply method are applied to the thermoelectric field.

Description

technical field [0001] The invention relates to a heating system and a heating method for a wide-range condensing type 600MW unit of steam ejection. Background technique [0002] With the increase of the heating area of ​​urban and rural buildings in northern my country and the national energy conservation and environmental protection requirements, a large number of water heaters and small thermal power units have been shut down, and large thermal power units have gradually become the main heat source for central heating in northern cities and towns in my country. The large-scale thermal power units that have been built mainly use condensing coal-fired units as the main unit, and the 600MW condensing unit occupies the main power generation task of thermal power units in the northern region. Most of the large-scale cogeneration units in my country are transformed from pure condensing units, not specially designed heating units, and there is a common problem of high pressure i...

AI Technical Summary

Problems solved by technology

This method has the following obvious defects: 1. The exhaust steam pressure of the unit in winter is generally around 4kPa. Artificially increasing the exhaust back pressure of the unit to 8-10kPa will significantly reduce the economical efficiency of the main engine operation (for wet-cooled units, every 1kPa increase in back pressure , corresponding to an increase of about 2g / kWh of coal consumption for power generation of the unit, so artificially increasing the back pressure of 4~6kPa corresponds to an increase of about 8~12g / kWh of coal consumption of the unit for power generation, which will greatly offset the economy of heat pump recovery of waste heat; The performance of the working condition is poor. When the pressure of the driving steam source (exhaust steam extraction in the main engine) is reduced due to deep peak regulation, its energy efficiency ratio will drop sharply, which directly leads to the fact that it is almost impossible to effectively extract low-level waste heat, so its wide-load adaptability is poor , with the increasing demand for peak regulation of large thermal power units in my country, the operating economy of absorption heat pumps is deteriorating

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