Intermittent blowdown flash tank with self water sealing function and drainage system and method

Abstract

The invention discloses an intermittent blowdown flash tank with a self water sealing function and a drainage system and method. The intermittent blowdown flash tank with the self water sealing function comprises an intermittent blowdown flash tank body, at least two drainage outlets are formed in the bottom of the intermittent blowdown flash tank body, a flow guiding pipe communicating with one drainage outlet is arranged in the intermittent blowdown flash tank body, and the height of the flow guiding pipe is higher than the lowest maintaining water level of the intermittent blowdown flash tank. A flow guiding hole is formed in the part, above the lowest maintaining water level of the intermittent blowdown flash tank, of the pipe wall of the flow guiding pipe, and the formed position of the flow guiding hole can ensure that the water stored in the intermittent blowdown flash tank can be always maintained at a lowest water level. The intermittent blowdown flash tank has the beneficialeffects that the system is greatly simplified and optimized, backflow of a corrosive medium in a drainage tank is prevented, and thus the safety of a machine unit is improved. The intermittent blowdown flash tank with the self water sealing function and the drainage system are particularly suitable for design of drainage systems for starting intermittent blowdown flash tanks of boilers, small machine units and gas turbine waste heat boilers.

Description

technical field [0001] The invention relates to the related technical field of power plants, in particular to a regular sewage discharge expansion vessel with self-water sealing function, a drainage system and a method. Background technique [0002] At present, the length of the sewage outlet pipe of the commonly used fixed-row expansion vessel extending into the expansion vessel is 0, and its purpose is to empty the water in the expansion vessel as completely as possible. However, the expander faces the problem of scouring, and the prior art discloses (such as CN103353106A) that it adopts a wear-resistant lining stainless steel plate or adds a buffer plate, a deflector (such as CN206269112U), a spray energy dissipation device (such as CN206269112U) at the fixed discharge inlet CN103277787A) and other schemes. In essence, the above schemes use hard materials or parts that are easy to be repaired and replaced (such as spray pipes) to replace the steel plate at the bottom of ...

AI Technical Summary

Problems solved by technology

However, since the working medium in the expansion vessel is mainly from the blowdown of the boiler steam drum, the salt content is high, and with the heat exchange process, the water temperature decreases, and the solubility of the salt in the sewage decreases greatly, so it is easy to be deposited on the surface of the heat exchanger. Formation of fouling, resulting in frequent maintenance of heat exchangers

When the heat exchanger is located inside the fixed-row expansion vessel, it is even necessary to stop the fixed-row expansion vessel to overhaul the heat exchanger. When the fixed-row expansion vessel is disabled, it needs to be shut down, which greatly affects the stable operation of the unit; even when When the heat exchanger is located outside the fixed row expansion vessel, due to the inherent cause of the salt content of the working medium itself, the heat exchanger is seriously fouled, and frequent maintenance is required, which seriously affects the efficiency of the heat exchanger user (such as heating into the furnace cold air in CN202303326U). Reliability and user experience, its overhaul and maintenance costs are even higher than the energy it recovers

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