RU2214556C1 - Steam boiler - Google Patents

Abstract

FIELD: steam generation, possibly in heat power stations and boiler aggregates. SUBSTANCE: steam boiler includes at least one stage for evaporation of boiler water; pipeline for blow-through water; steam duct; blow-through water flowrate controller connected with pickup for measuring salt content of saturated steam mounted on steam duct and with adjusting organ mounted in pipeline for blow-through water. EFFECT: enhanced reliability, improved efficiency of steam boiler operation. 1 dwg

Description

 The invention relates to the field of power engineering and can be used in thermal power plants and boiler plants.

 A known analogue is a steam boiler (see A. Fedorov. Methodology for calculating a three-stage scheme for boiler water evaporation of drum boilers. - Electric stations, 1997, 11. P. 10), containing at least one boiler water evaporation stage, a pipeline connected to the boiler purge water and steam line. This analogue is taken as a prototype.

 The reason that impedes the achievement of the technical result indicated below when using a well-known boiler adopted as a prototype is that in a known steam boiler the amount of purge water removed from the last evaporation stage is constant and depends only on the pressure in the boiler and its steam capacity. During the operation of the boiler, the quality of the saturated steam generated by it can change. A decrease in the quality of saturated steam obtained in the boiler or an increase in its salt content from the standard value leads to an intensive deposition of scale on the inner surface of the pipes of the superheater and heat exchangers. The reduced quality of the saturated steam produced by the boiler indicates an increased salt content of the boiler water, moving along the circulating circuits of the steam boiler, which in turn leads to an acceleration of the formation of deposits on the internal heating surfaces of the steam boiler, disruption of its normal operation and intensive corrosion processes, which can occur in relatively short time to disable equipment. In addition, when the salt content of the saturated steam generated by the boiler is lower than the standard value, which indicates a lower salt content of the boiler water, the removal of a constant amount of purge water from the last stage of evaporation leads to an increase in the loss of the mass of boiler water and the heat contained in it, which reduces the efficiency of the steam boiler .

 The technical result of the claimed solution is to increase the reliability and efficiency of the steam boiler.

 The invention consists in the following.

 To increase the reliability and efficiency of the steam boiler, it is advisable to automatically control the flow rate of purge water according to the salinity of saturated steam. To do this, it is proposed to install a purge water flow regulator in the steam boiler connected to a saturated steam salinity sensor installed on the steam line and a regulating body installed on the purge water pipeline.

 The specified technical result in the implementation of the invention is achieved by the fact that the known steam boiler contains at least one evaporation stage of boiler water, a purge water pipe and a steam pipe connected to the boiler. The peculiarity lies in the fact that the boiler is equipped with a purge water flow regulator connected to a saturated steam salinity sensor installed on the steam line and a regulating body installed on the purge water pipeline.

 The drawing shows a diagram of a steam boiler.

 The steam boiler contains the first intra-drum stage of boiler water evaporation 1, the second intra-drum stage of boiler water evaporation in the form of a built-in compartment 2, the third stage of boiler water evaporation in the form of an external cyclone 3, purge water pipe 4, purge water flow controller 5 connected to the salinity sensor 6 saturated steam and the regulating body 7 of the flow rate of purge water, the pipe 8 of the feed water, the regulating body 9 of the flow of feed water, the steam line 10.

 The operation of the steam boiler is as follows.

 Feed water through the pipe 8 is supplied to the first intra-drum stage of evaporation of boiler water 1 (clean compartment). Continuous purging of the steam boiler is carried out through pipeline 4 from the third stage of evaporation of the boiler water of the external cyclone 3 (salt compartment). During operation of the steam boiler, the salt content of saturated steam is determined by a sensor 6 installed on the steam line 10. The signal from the sensor 6 is continuously fed to the input of the purge water flow regulator 5, the output of which is connected to the purge water flow regulator 7 installed on the pipeline 4. In the case of when the salt content of saturated steam exceeds the normalized value by a signal from the sensor 6, the controller 5 generates a command signal to increase the flow rate of purge water. The command signal generated by the regulator 5 acts on the regulatory body 7, which increases the flow rate of purge water. By increasing the flow rate of purge water, they achieve a decrease in the salt content of the boiler water moving along the circulating circuits of the steam boiler, and, as a result, a decrease in the salt content of the saturated steam produced by the boiler to the standard value. If the opposite situation occurs, when the salt content of the saturated steam generated by the boiler is below the standard value, which indicates a lower salt content of the boiler water, the automatic control system reduces the flow rate of the purge water. By reducing the flow rate of purge water, the mass loss of the boiler water and the heat contained therein are reduced.

 The boiler water level in the first stage of evaporation 1, at which the normal operation of the steam boiler is ensured, is supported by a change in the flow of feed water by the regulatory body 9 installed on the pipeline 8.

 Thus, the installation of a purge water flow controller connected to a saturated steam salinity sensor and a regulating body for the purged water flow allows the process to automatically control the purged water flow rate based on the saturated steam salinity, which ensures the standard value of the saturated steam salinity and, in general, increases reliability and economy steam boiler operation.

Claims (1)

 Steam boiler containing at least one stage of boiler water evaporation, purge water pipe and steam pipe connected to the boiler, characterized in that the boiler is equipped with a purge water flow controller connected to a saturated steam salinity sensor installed on the steam pipe and a regulating body mounted on the purge pipe water.