JPS61134509A - High pressure system clean-up system of plant - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a breboiler cleanup, and particularly to a preboiler cleanup system that shortens the free/up time.

[Background of the invention]

Conventionally, in a steam turbine plant of a thermal power plant, water condensed in a condenser is sent to a boiler via a desalination device, various preheaters, a low-pressure feed water heater (hereinafter referred to as a low-pressure heater), a deaerator, and a high-pressure heater. reach The water supply that flows through these systems contains impurities consisting of iron, copper, and other elements that adhere to pipes and heaters. When these impurities are brought into the boiler, they adhere to the walls of the evaporator tubes and form scales that inhibit heat transfer, causing the tube material to overheat and sometimes causing the evaporator tubes to burst. For this reason, water quality standards for boiler feed water have been established to prevent the accumulation of corrosion products inside the turbine and boiler. The boiler and pre-boiler were not cleaned up as there was a risk of exceeding the standard control values. In the preboiler system, cleanup is performed for each system, and jIk ultimately satisfies the water flow standard value of the boiler.

Next, the cleanup of a conventional general preboiler system will be briefly explained with reference to the third drawing.

Conventionally, cleanup of a preboiler system proceeds in the following order: condensate recirculation line cleanup -> low pressure ink cleanup -> high pressure ink/cleanup.

In other words, in condensate recirculation/cleanup, a closed circuit of condenser 1 → condensate pump 2 → desalination device 3 → condensate recirculation line 10 → condenser 1 is formed, and the main After blowing and circulating the circuit to satisfy the low pressure heater water flow standards, proceed to the next step, low pressure cleanup.

In low pressure line cleanup, condenser 1 → condensate pump 2 → demineralizer 3 → low pressure heater 4 → deaerator 5 → deaerator water tank 6 → low pressure cleanup line 13 → condenser 1
Forms a closed circuit, blows out impurities in the system, and circulates 3II
After improving the grain texture and satisfying the high-pressure heater water flow standards, the next high-pressure line cleanup is performed.

High pressure cleanup is performed by condenser 1 → condensate pump 2 → demineralizer 3 → low pressure heater 4 → deaerator 5 → deaerator water tank 6 → water booster pump 7 → water pump bypass line 14 →
High pressure heater 9 → high pressure clean up line 16 → condenser 1 closed circuit to improve grain quality through sieving and circulation.
Satisfy boiler water flow standard values.

As described above, in each cleanup, the initial wastewater containing a lot of iron and other impurities is blown out of the system, and when the purity has increased to a certain degree, it is switched to circulation, and removed by the desalination equipment in each circulation circuit. Cleanup will be carried out to reach water quality target values, and the scope of cleanup will be gradually expanded.

For this reason, in high pressure line cleanup, Uf
c8E In the low pressure line removed during line cleanup, there was dirt that deteriorated the water quality in the high pressure line/inside 1
The water is allowed to flow in again, and the waste water from the high-pressure heater, which has a particularly high iron content, is passed through a desalination device and cleaned up by blowing and circulation, so a large amount of pure water is used and it takes a long time.

FIG. 4 shows the relationship between the conventional cleanup process and the iron concentration.

[Purpose of the invention]

In order to improve the above-mentioned prior art, the present invention implements a low pressure cleanup system and a high pressure cleanup system simultaneously, and in particular, performs the cleanup of the high pressure heater circuit alone, which conventionally took a lot of time. The purpose is to save pure water, shorten clean-up time, and reduce auxiliary machine power.

[Summary of the invention]

The present invention is based on the experience that high-pressure heater rotation takes a lot of time during pre-boiler cleanup and is difficult to remove iron.The present invention provides a separate leak/up system for the high-pressure heater and uses an electromagnetic filter to remove iron. This method effectively removes the wastewater and can be performed simultaneously with the low-pressure cleanup system, thereby making it possible to shorten the time required for cleanup.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG.

Note that the same parts as in FIG. 3 are indicated by the same reference numerals.

The difference from FIG. 3 is that a system branched from the high-pressure cleanup system 16 and connected to the water supply booster pump inlet pipe 20, an electromagnetic filter 21, and a switching valve 23°24.25 are installed. , is the same as in FIG.

The cleanup operation method according to the present invention is shown below.

The feature of the operation method according to the present invention is that low-pressure cleanup and high-pressure cleanup can be carried out simultaneously.Although it is necessary to supply water 11D and replenishment to the high-pressure cleanup system, water is supplied from the make-up water system. The booster pump may be supplied with water alone, or the switching valve 23 may be opened to supply water from the condensate system.

Low pressure cleanup operation method is condenser 1 → condensate pump 2
→ Desalination equipment fit 3 → Low pressure heater 4, deaerator water storage tank 6 to condenser 1 (through stop valve 19), blowing, blowing and circulation are performed. In this case, the iron removal effect by low-pressure cleanup is made possible by the desalination device 3.

On the other hand, the high-pressure cleanup operation method is carried out simultaneously with low-pressure cleanup, so the high-pressure cleanup system hydrophilic I! l! After completing the switching, the switching valves 23 and 28 are fully closed, the water booster pump 7 is started, and the water booster pump 7 is activated.
→ Water supply pump bypass system 14 → Via high pressure heater 9,
The high-pressure clean-up system 21 of the present invention → the electromagnetic filter 22 → the switching valve 25, and the closed circuit that reaches the water supply booster pump 7 performs sieving and circulation. In this case, the electromagnetic filter 22 can remove iron.

According to the above operation method, low-pressure cleanup and high-pressure cleanup were carried out simultaneously, and after checking the water quality, the entire preboiler was cleaned up by fully opening the switching valve 23.28 and 24.25.
Switch to fully closed, condenser 1 → condensate port/tub 2 → desalination equipment 3
→ Low pressure heater 4 → Deaerator 5 → Water booster pump 7 → Water pump bypass system 14 → High pressure heater 9 → High pressure cleanup system 16 → Condenser 1.
In order to further increase the iron removal effect, auxiliary steam 12 is added to the deaerator 5.
The aim is to remove iron by heating.

The expected effects of preboiler cleanup according to the present invention are shown in FIG.

From Figure 2, the effects of the preboiler system are as follows: Condensate plow, condensate recirculation, and
The high-pressure heater rotation can be cleaned up at the same time as the low-pressure cleanup, making it possible to significantly shorten the overall preboiler cleanup time.

〔Effect of the invention〕

According to the above explanation, it is possible to carry out continuous high-pressure clean-up, which has traditionally taken a lot of time, at the same time as low-pressure clean-up, and to increase the effect of iron removal using electromagnetic filters. The time can be drastically reduced.

In addition, with the shortening of the time required for cleanup, there is also the effect of saving pure water used and reducing the power of auxiliary equipment such as pumps.

[Brief explanation of drawings]

Figure K1 is a system diagram showing an embodiment of the present invention, Figure 2 is an explanatory diagram showing the cleanup process and iron concentration according to the present invention, Figure 3 is a system diagram showing a conventional preboiler cleanup system, and Figure 4 is a system diagram showing an example of the present invention. The figure is an explanatory diagram showing a conventional cleanup process and iron concentration. 1... Condenser, 2... Condensate pump, 3... Desalination device, 4... Low pressure heater, 5... Deaerator, 7... Water supply booster pump, 9... - High pressure heater, 11... Condensate system, 22... Electromagnetic filter, 23-25... Switching valve.

Claims (1)

[Claims] 1. A deaerator for removing dissolved gas in the feed water, a feed water pump alone, or a steam generator feed water supply system with a feed water booster pump installed in series, a high pressure feed water heater, and pipes connecting the equipment group. In the water supply system of a steam power plant consisting of valves, a circulation circuit is provided that branches from the final high-pressure feedwater heater outlet water supply pipe and connects to the steam generator feedwater supply system inlet pipe, and The circulation method is a high-pressure cleanup system for a plant that is configured to flow through an undissolved solids removal device that is installed exclusively or is used in conjunction with other equipment.