CN213300059U - Washing system for salt deposition of power station boiler system - Google Patents

Abstract

The utility model discloses a flushing system for the salt deposition of a power station boiler system, which comprises a temporary water inlet pipeline and a temporary water inlet valve, wherein the temporary water inlet pipeline is communicated with a condensed water pipeline and a low-pressure bypass pipeline of the power station boiler system; the temporary short connecting pipe is communicated with a reheater system and a superheater system of the power station boiler system; the system comprises a unit drainage tank, a sampling valve, a pressure gauge and a temporary discharge valve, wherein the unit drainage tank is communicated with a lower water packet of a power station boiler system through a temporary discharge pipe; controlling the content of the sodium ions in the discharged water to be less than 20 mug/L by the flushing system; the utility model discloses system design is simple, reliable and easily realize, has solved coastal power plant and has caused the problem of the unable normal operating of boiler heating surface long-pending salt, unit because of condenser leakage.

Description

Washing system for salt deposition of power station boiler system

Technical Field

The utility model belongs to lead to the sea water to get into boiler steam system because of condenser heat exchange tube leaks, cause the long-pending salt of boiler steam system, concretely relates to rinse-system and washing method of power plant boiler system long-pending salt.

Background

Once the condenser leaks seawater, the quality of water vapor is deteriorated, and finally salt accumulation in a water vapor system of the boiler is caused, so that a unit cannot normally operate. Especially, when the elbow salt deposition is serious under superheater and the reheat device's "U" type or "W" type heat exchange tube, then need carry out the water washing, in the water washing in-process, final superheater and high temperature reheat ware "W" type heat exchange tube probably take place the gas lock and lead to not circulating in the heat exchange tube, along with the continuous evaporation of ponding in the heat exchange tube in the start-up process like this, can cause the final elbow of dissolving in the heat exchange tube to concentrate under and separate out, there is the risk of jam the elbow under the heat exchange tube, thereby probably lead to the booster. Therefore, under the condition, the small-flow washing of the boiler by the existing conditions has a higher risk, a condensate pump is needed to be utilized, and a certain auxiliary system is designed, so that the large-flow washing of the boiler is realized, the salt content possibly remaining due to air plugs of a boiler superheater system and a boiler reheater system is thoroughly eliminated, and the problem of salt accumulation caused by seawater leakage of the boiler superheater system and the boiler reheater system can be completely solved by using the washing system and the method at present.

Disclosure of Invention

In order to solve the problems existing in the prior art, the utility model aims to provide a washing system for power station boiler system salt deposition, this system design is simple, reliable and easily realize, has solved the condenser heat exchange tube and has taken place the sea water and leak and cause boiler superheater and reheater system salt deposition to lead to the unable normal operating of unit problem.

In order to achieve the purpose, the utility model adopts the following technical proposal,

a washing system for salt deposition of a power station boiler system comprises a temporary water inlet pipeline 8 for communicating a condensed water pipeline 5 and a low-pressure bypass pipeline 6 of the power station boiler system, and a temporary water inlet valve 9 arranged on the temporary water inlet pipeline 8; a temporary short pipe 13 for connecting the reheater system 10 and the superheater system 14 of the utility boiler system; a unit drainage tank 22 communicated with a lower water drum 17 of the utility boiler system through a temporary drainage pipe 18, and a sampling valve 19, a pressure gauge 20 and a temporary drainage valve 21 arranged on the unit drainage tank 22; flushing water simultaneously enters a first condensate pump 2-1 and a second condensate pump 2-2 through a condenser 1 to be collected, then sequentially enters a condensate pipeline 5, a temporary water inlet pipeline 8 and a temporary water inlet valve 9 to enter an inlet of a reheater system 10, then simultaneously enters a superheater system 14 from an outlet of the reheater system 10 through a high bypass pipeline 11, a high bypass valve 12 and a temporary short connecting pipe 13, and then sequentially enters a unit drainage tank 22 through a steam drum 15, a water wall 16, a drainage drum 17, a temporary discharge pipe 18 and a temporary discharge valve 21 to form a reverse flushing loop.

And a temporary plugging plate 7 is arranged at the communication part of the temporary water inlet pipeline 8 and the low-pressure bypass pipeline 6 for plugging.

The pH value of system flushing water is adjusted by means of a condensed water ammonia adding point in a power station boiler system, the flushing water is heated by means of four-section steam extraction in the power station boiler system, the temperature of the flushing water is increased, and a temporary dosing system and a temporary heating system do not need to be connected.

According to the method for flushing the salt accumulation flushing system of the power station boiler system, a condenser 1 of the power station boiler system is replenished with water to a high liquid level, a first condensate pump 2-1 is started to replenish water to a deaerator 4, the flow of the replenished water is regulated through a condensate self-circulation valve 3, the internal circulation of the deaerator 4 and the condenser 1 is established, the pH value of the water is regulated to be larger than 10.0 through adding ammonia, the deaerator 4 is heated, heating is stopped when the temperature of the water reaches 50-70 ℃, exhaust valves of a reheater system 10, a superheater system 14, a steam drum 15 and a water cooling wall 16 are opened in sequence, a temporary water inlet valve 9 is gradually opened, water is slowly supplied to the power station boiler system, an exhaust valve is closed in sequence when the exhaust valves of the reheater system 10, the superheater system 14, the steam drum 15 and the water cooling wall 16 all have continuous water flow, a sampling valve 19 and a temporary water inlet valve 9 are gradually opened when the reading of a pressure gauge, closing the condensate self-circulation valve 3, starting a second condensate pump 2-2 (frequency conversion regulation) at the same time, and carrying out large-flow water washing on a reheater system 10, a superheater system 14 and a water wall 16 of a power station boiler system; when the condenser 1 reaches a low liquid level, the first condensate pump 2-1 and the second condensate pump 2-2 are switched to self-circulation operation, the tube panels of the reheater system 10 and the superheater system 14 are subjected to temperature measurement or DCS auxiliary inspection, so that the tube panels of the reheater system 10 and the superheater system 14 are confirmed to be free of air plugs, namely the tube panels of the reheater system 10 and the superheater system 14 are in a circulation state; sampling at a sampling valve 19 during the flushing process to determine the content of sodium ions in the drained water; if the content of sodium ions is more than 20 mug/L, the steps are repeated for repeated washing until the content of the sodium ions in the drainage water is less than 20 mug/L.

A temporary washing pump is not needed to be connected, and a first condensate pump 2-1 and a second condensate pump 2-2 of the power station boiler system are used as washing power.

The flushing discharge water does not need to be subjected to advanced treatment, and can meet GB 8978 Integrated wastewater discharge Standard by only adjusting the pH value.

When the content of the sodium ions in the discharged water is less than 20 mug/L, the cold state and hot state flushing water quality of the utility boiler system can meet the requirement of GB/T12145 in a short period.

Compared with the prior art, the utility model has the advantages of as follows:

1) a condensate pump is adopted to provide flushing power, and a deaerator is adopted to heat flushing water;

2) a temporary water inlet pipeline is designed between the condensed water and the low side to serve as a boiler washing water inlet pipe, the low side pipeline is temporarily blocked at the side of a condenser, and a reheater, a superheater and a water wall system are sequentially washed reversely through a high side pipeline and a steam drum;

3) because the sectional area of a tube panel of a reheater is much larger than that of a superheater, particularly, a W-shaped tube of a high-temperature reheater possibly has gas blockage of partial tubes due to small flow velocity, so that no effective flushing salt can be obtained, according to the calculation of the sectional area of the reheater system, the partial tube panel of the high-temperature reheater is in short connection with a tube panel of a final superheater through a temporary tube, so that the overall flushing flow of the reheater is improved, the gas blockage of the reheater system is judged and eliminated by measuring the wall temperature of the tube panel, and the flushing effect of all the tube panels is ensured;

4) a temporary pipe is connected from the sewage bag to serve as a flushing discharge pipeline, the temporary discharge pipeline is provided with an on-site pressure gauge and a sampling point to control flushing flow and a flushing end point, and the flushing end point is used for sampling and detecting that the content of sodium ions in drained water is less than 20 mu g/L.

5) The system is simple in design, reliable in performance and easy to implement;

6) the problem that salt is accumulated in a boiler superheater and a reheater system to cause the unit to run normally due to the fact that seawater leaked from a heat exchange tube of the condenser enters a water vapor system is effectively solved.

Drawings

FIG. 1 is a schematic view of the flow of the system and method for washing the salt accumulated in the utility model of the utility model.

In the figure: 1-a condenser; 2-1-a first condensate pump; 2-2-a second condensate pump; 3-condensate self-circulating valve; 4-a deaerator; 5-a condensate pipeline; 6-a low pressure bypass line; 7-temporary blocking plate; 8-temporary water inlet pipeline; 9-temporary water inlet valves; 10-a reheater system; 11-high side pipe; 12-high bypass valve; 13-temporary nipples; 14-a superheater system; 15-steam drum; 16-a water-cooled wall; 17-a water tank; 18-a temporary drain; 19-a sampling valve; 20-pressure gauge; 21-a temporary drain valve; 22-unit drain tank.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and specific embodiments.

As shown in fig. 1, the utility model relates to a system for washing salt deposition in a utility boiler system, which comprises a temporary water inlet pipeline 8 for communicating a condensed water pipeline 5 and a low-pressure bypass pipeline 6 of the utility boiler system, and a temporary water inlet valve 9 arranged on the temporary water inlet pipeline 8; a temporary short pipe 13 for connecting the reheater system 10 and the superheater system 14 of the utility boiler system; a unit drainage tank 22 communicated with a lower water drum 17 of the utility boiler system through a temporary drainage pipe 18, and a sampling valve 19, a pressure gauge 20 and a temporary drainage valve 21 arranged on the unit drainage tank 22; flushing water simultaneously enters a first condensate pump 2-1 and a second condensate pump 2-2 through a condenser 1 to be collected, then sequentially enters a condensate pipeline 5, a temporary water inlet pipeline 8 and a temporary water inlet valve 9 to enter an inlet of a reheater system 10, then simultaneously enters a superheater system 14 from an outlet of the reheater system 10 through a high bypass pipeline 11, a high bypass valve 12 and a temporary short connecting pipe 13, and then sequentially enters a unit drainage tank 22 through a steam drum 15, a water wall 16, a drainage drum 17, a temporary drainage pipe 18 and a temporary drainage valve 21 to form a reverse flushing loop.

As the utility model discloses a preferred embodiment sets up interim closure plate 7 in interim inlet channel 8 and 6 intercommunication departments of low pressure bypass pipeline and adds stifled, carries out reverse washing to re-heater, over heater and water-cooled wall system through high other pipeline, steam pocket in proper order.

The utility model discloses adjust the pH value of system's sparge water with the help of the condensate water in the power plant boiler system with the aid of the four sections steam extractions in the power plant boiler system heat the sparge water, improve the temperature of sparge water, need not to insert interim medicine system and interim heating system.

As shown in figure 1, the utility model discloses a method for flushing the system for flushing the salt deposition in the utility model, the condenser 1 of the utility boiler system replenishes water to a high liquid level, the first condensate pump 2-1 is started to replenish water to the deaerator 4, the flow rate of the replenished water is adjusted through the condensate self-circulation valve 3, the internal circulation of the deaerator 4 and the condenser 1 is established, the pH value of the water is adjusted to be more than 10.0 through adding ammonia, the deaerator 4 is heated, the heating is stopped when the temperature of the water reaches 50-70 ℃, the exhaust valves of the reheater system 10, the superheater system 14, the steam pocket 15 and the water wall 16 are opened in sequence, the temporary water inlet valve 9 is gradually opened, the water is slowly supplied to the utility boiler system, the exhaust valves of the reheater system 10, the superheater system 14, the steam pocket 15 and the water wall 16 are closed in sequence when continuous water flows exist in sequence, when the reading of the pressure gauge 20 reaches 0., gradually opening a large sampling valve 19 and a temporary water inlet valve 9, closing a condensate self-circulation valve 3, simultaneously starting a second condensate pump 2-2 (frequency conversion regulation), and carrying out large-flow water washing on a reheater system 10, a superheater system 14 and a water wall 16 of a power station boiler system; when the condenser 1 reaches a low liquid level, the first condensate pump 2-1 and the second condensate pump 2-2 are switched to self-circulation operation, the tube panels of the reheater system 10 and the superheater system 14 are subjected to temperature measurement or DCS auxiliary inspection, so that the tube panels of the reheater system 10 and the superheater system 14 are confirmed to be free of air plugs, namely the tube panels of the reheater system 10 and the superheater system 14 are in a circulation state; sampling at a sampling valve 19 during the flushing process to determine the content of sodium ions in the drained water; if the content of sodium ions is more than 20 mug/L, the steps are repeated for repeated washing until the content of the sodium ions in the drainage water is less than 20 mug/L.

The utility model discloses washing method need not to insert interim washing pump, with the help of the first condensate pump 2-1 and the second condensate pump 2-2 of power plant boiler system as washing power.

The flushing discharge water does not need to be subjected to advanced treatment, and can meet GB 8978 Integrated wastewater discharge Standard by only adjusting the pH value.

When the content of the sodium ions in the discharged water is less than 20 mug/L, the cold state and hot state flushing water quality of the utility boiler system can meet the requirement of GB/T12145 in a short period.

Claims (2)

1. The utility model provides a rinse-system of power plant boiler system accumulated salt which characterized in that: the system comprises a temporary water inlet pipeline (8) for communicating a condensed water pipeline (5) and a low-pressure bypass pipeline (6) of a power station boiler system, and a temporary water inlet valve (9) arranged on the temporary water inlet pipeline (8); a temporary short-circuiting pipe (13) for connecting a reheater system (10) of the utility boiler system and a superheater system (14); a unit drainage tank (22) communicated with a lower water bag (17) of the utility boiler system through a temporary discharge pipe (18), and a sampling valve (19), a pressure gauge (20) and a temporary discharge valve (21) which are arranged on the unit drainage tank (22); washing water simultaneously enters a first condensate pump (2-1) and a second condensate pump (2-2) through a condenser (1) to be collected, then sequentially enters a condensate pipeline (5), a temporary water inlet pipeline (8) and a temporary water inlet valve (9) to enter an inlet of a reheater system (10), and then simultaneously enters a superheater system (14) from an outlet of the reheater system (10) through a high bypass pipeline (11), a high bypass valve (12) and a temporary short connecting pipe (13), and then sequentially enters a steam drum (15), a water wall (16), a lower water drum (17), a temporary discharge pipe (18) and a temporary discharge valve (21) to enter a unit drain tank (22), so that a reverse washing loop is formed.

2. The utility boiler system saltation rinse system of claim 1 further characterized by: a temporary plugging plate (7) is arranged at the communication part of the temporary water inlet pipeline (8) and the low-pressure bypass pipeline (6) for plugging.

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