CN1131738C

CN1131738C - Cleaning method for power plant installation set

Info

Publication number: CN1131738C
Application number: CN96121849A
Authority: CN
Inventors: B·约迪; R·库斯克
Original assignee: Alstom SA
Current assignee: Alstom SA
Priority date: 1995-12-02
Filing date: 1996-12-02
Publication date: 2003-12-24
Anticipated expiration: 2016-12-02
Also published as: JP3893178B2; EP0776707A3; CN1156241A; EP0776707B1; EP0776707A2; JPH09173999A; DE19545035A1; DE59606231D1

Abstract

The invention provides a method for cleaning a group of devices of an assembled power generating equipment. A thermally prepared medium is blown under pressure into a group of the devices to be cleaned for several hours, the cleaning is then suspended to cool the group, and the blowing producing a cleaning effect due to the thermal shock is intermittently conducted at least once after the group are cooled.

Description

The clean method of power plant equipment unit

The present invention relates to a kind of by spraying into a kind of working medium to being in the clean method that the power plant equipment unit under the serviceable condition is installed.

Particularly jet chimney, evaporimeter, superheater etc. must clean in power plant equipment, particularly combined cycle equipment (fuel gas-steam power plant equipment).Under normal circumstances, this cleaning is being carried out before the operation first, and its final purpose is, the prevention unit particularly turbine for example steam turbine in installation process or when said system is checked, inevitably pollute.The term that this cleaning course is commonly used is called " removing ".

Two kinds of known method are arranged in principle: a kind of is to clean continuously with big surge ratio.Another kind of then be that removing with circulation impact to produce big thermal shock.

Can reach a good cleaning effect rapidly when removing continuously with big surge ratio.But as further clean with steam more immediately after the vapour system that the is cleaned cooling, then can reach highly effective, an additional cleaning effect by thermal shock.This can be used as a sign that whether also has dirt in the system of being evaluated at.The method of HI high impact pressure ratio attempt before superheater or in superheater water spray into and cause thermal shock.This thermal shock effect that produces in the dirty jet chimney of superheater is very little.In addition, many waste heat boilers manufacturing firm opposes that in technical conditions water sprays into before superheater or in the superheater, and this fact also is a factor that has a strong impact on this cleaning course.In addition, when removing, can not be ignored such important disadvantages, promptly carry out this method and need expend a large amount of time with thermal cycle.

When mid power and general combined cycle equipment with two waste heat boilers, remove required cleaning time with thermal cycle and be approximately 20 days, and when removing continuously with big surge ratio, then need 3 to 5 days, but cleaning effect is so not big.

The objective of the invention is, propose a kind ofly to start described clean method and reach maximum cleaning effect and minimum checkout time.

Major advantage of the present invention is to draw the advantage of above-mentioned two kinds of methods, and abandon their shortcoming.

The method according to this invention is removed several hrs with big surge.Checkout time depends on used de-mineralized water source or its preparation of generation steam.For example stop to remove then, system cool off and water treatment facilities can be the new demineralized water of removing preparation next time in this time at night.The removing of carrying out subsequently is to produce a thermal shock.As mentioned above, this thermal shock produces a big cleaning effect.After corresponding cooling, repeat the big cleaning effect that continuous removing often can increase last time thermal shock with big surge, and only need seldom that several cycles just can reach highly effective cleaning.

Describe one embodiment of the present of invention in detail below in conjunction with accompanying drawing, and for distinguish and better understand for the purpose of, quote known two methods of prior art and compare.Every directly to understand the unwanted data of the present invention all deleted, and adopt identical reference symbol to represent identical method step in different figure.

Accompanying drawing is represented:

Fig. 1 a, 1b represent the curve map of prior art sweep-out method;

Fig. 2 a, 2b represent the curve map of prior art another kind method;

Fig. 3 a, 3b represent the curve map of sweep-out method of the present invention.

Fig. 1 a and 1b represent that producing a big thermal shock by prior art with short loop cleaning impact itself comes being in a kind of method that the generating equipment unit under the serviceable condition cleans of installing.Single removing impact A, B approximately carried out once with a kind of suitable working medium in per 12 hours, shown in abscissa t.The temperature T of used working medium is about 500～550 ℃, surge than P then greater than 1.About the various pluses and minuses of this sweep-out method chat in front and, but recapitulaion is: remove with heat shock cycling and can produce good cleaning effect, but consider the peak use rate of electric power factory equipment by contemporary standard, the required time of this method then dislikes oversize.

Fig. 2 a and 2b represent the another kind of method of to being in the prior art that the power plant equipment unit under the serviceable condition cleans being installed with removing continuously, as in hour the curve C, D of abscissa t top shown in.The temperature T of used working medium is quite low, is lower than 400 ℃, surge than P then up to about 3.Pluses and minuses about this sweep-out method are mentioned in front, can be summarized as: with quite high surge than continuous removing method itself reach a good cleaning effect very soon, but can not thoroughly dispose the dirt particle of firm attachment owing to do not produce thermal shock.

Fig. 3 a and 3b represent the method that the power plant equipment unit of installing under the serviceable condition cleaned according to the present invention.This method is higher than at moderate temperature T than P with about big surge more than 4 under 400 ℃ the situation works.Shown in abscissa t lattice, several hrs is carried out in this removing at every turn, and this also can find out from curve E, F.Wherein, checkout time is mainly relevant with the de-mineralized water source or its preparation that are used for producing steam.Then, for example stop to remove at night, so as system to be cooled off during this period and before repeating this method water treatment facilities be ready to new demineralized water for removing next time.Each thermal shock of removing generation all reaches a big cleaning effect.That carries out than P with big surge then removed the big cleaning effect that (seeing curve E and F) strengthens thermal shocks in several hours.In reset procedure, cause high surge ratio by high speed.In the system that is cleaned, keep little pressure, thereby when keeping bigger specific volume, just can reach high speed.Be preferably in and the very little silencer of pressure loss and Xiang Guanzhong are set in the interim pipeline spray water and set up these operating modes.Spray into water and directly carry out, thereby in the system that is cleaned, cause a little pressure, reach the big scavenging action of steam simultaneously at the initiating terminal of temporary pipeline.Thereby reached an additional effect that Fig. 2 a, 2b method also have in this way: interim removing pipeline is without undergoing the such big stress of prior art additive method.Compare with the method for Fig. 2 a, 2b, the advantage of the inventive method is that water consumption is very little, because most cases shows that used water is limited.Another advantage of the inventive method is, basically gas turbine is cherished, and promptly needs the gas turbine starting and stops height to 50 comparisons with method shown in Fig. 1 a, the 1b, and the inventive method only needs about 5 startings and stops.

Symbol description

The temperature of T equipment

The t time, hour

P surge ratio

The relation of A thermal shock, number of times, duration and temperature T

B thermal shock, number of times, duration and the relation of stamping pressure than p

The relation of C removing continuously, duration and temperature T

The relation of D removing continuously, duration and surge p

The relation of E thermal shock and removing continuously, number of times, duration and temperature T

F thermal shock and removing continuously, number of times, duration and the relation of surge than p

Claims

1. by spraying into a kind of working medium to being in the clean method that the power plant equipment unit under the serviceable condition is installed, it is characterized in that, the working medium of heat is being higher than 400 ℃ temperature and is spraying into several hrs than the time greater than 4 surge, stop one period that makes unit be cooled to room temperature then, and after unit cooling, carry out another time at least and spray into identical the spraying into of condition with above-mentioned, spray into specifically by thermal shock generation cleaning effect.

2. by the method for claim 1, it is characterized in that this spraying into carried out 6 hours at least.

3. by the method for claim 1, it is characterized in that above-mentioned to spray into used working medium be steam.

4. by the method for claim 3, it is characterized in that, be mixed with a certain amount of water in the steam.

5. by the method for claim 3, it is characterized in that, when steam sprays into and/or at steam, a certain amount of water followed before or after spraying into to spray into.