Background technology
Hydrogen peroxide is as a kind of environmental protection passivator, and the application in the station boiler Chemical cleaning is more and more extensive.But because it has stronger oxidisability and very easily decomposition in passivating solution, therefore in use there are various problems in it.
At present, in the station boiler Chemical cleaning, the adding mode of hydrogen peroxide mainly contains two kinds: a kind of for directly adding in the cleaning case of purging system, this mode is simple to operate, but because hydrogen peroxide very easily decomposes in containing the high pH passivating solution of a large amount of iron ions, can cause on the one hand a large amount of wastes of medicine, also can cause that the vent plug of clean cycle pump causes the circulation of whole purging system not smooth because it decomposes the gas that produces on the other hand, this not only can affect passivation effect, also can cause the excessive of passivating solution; Another kind of adding mode is for adopting dosing pump cleaning the delivery side of pump adding, although this mode can solve the vent plug problem of scavenging pump, but have following problem: 1) hydrogen peroxide also can decompose in the dosing pump housing (carbon steel), thereby cause the dosing pump vent plug, directly affect the process of dosing; Dosing is interrupted, passivating solution can be occurred simultaneously and flow backward to medicine system and cause a large amount of decomposition of hydrogen peroxide in the short time; 3) if dosing pump operation control is improper, the dosing pump outlet pressure can occur less than the scavenging pump outlet pressure, can cause that also passivating solution flows backward to medicine system and causes a large amount of decomposition of hydrogen peroxide in the short time.
Summary of the invention
The object of the present invention is to provide the chemicals dosing plant of hydrogen peroxide in a kind of boiler of power plant Chemical cleaning of the vent plug phenomenon that can solve the gasification in the pump housing and cause.
For achieving the above object, the technical solution used in the present invention is: comprise the first dosing pump and the second dosing pump that are connected with dosing tank, entrance and export pipeline at the first dosing pump and the second dosing pump are separately installed with first, two dosing pump inlet valves and first, two dosing pump outlet valves, first, two dosing pump outlet valves are connected with the outlet main valve by the road, and first, two dosing pump inlet valves and first, also be separately installed with the first communication valve and the second communication valve between two dosing pumps, the outlet of the first communication valve and the second communication valve by the road respectively with the second dosing pump 3, the first dosing delivery side of pump is connected.
The outlet of the first communication valve of the present invention and the second communication valve also reaches by the road first and second recycle valve that is installed on the pipeline and is connected with dosing tank;
Also be separately installed with first and second Pressure gauge on the pipeline before first and second dosing pump outlet valve entrance;
On the pipeline between first and second dosing pump outlet valve and the outlet main valve non-return valve is installed also.
The present invention is equipped with 2 dosing pumps, by being used in conjunction with between 2 dosing pumps, but make its both the using and the reserved, also can parallel connection move simultaneously, the operation of can also connecting simultaneously, thus efficiently solve a large amount of decomposition that passivator hydrogen peroxide in the Boiler Chemical occurs in the purging system adition process and decompose after produce the problem such as the formed vent plug of gas.
The specific embodiment
Below in conjunction with accompanying drawing the present invention is described in further detail.
Referring to Fig. 1, the present invention includes the first dosing pump 2 and the second dosing pump 3 that are connected with dosing tank 1, entrance and export pipeline at the first dosing pump 2 and the second dosing pump 3 are separately installed with first, two dosing pump inlet valves 4,6 and first, two Pressure gauges 12,13, first, two dosing pump outlet valves 5,7, first, two dosing pump outlet valves 5,7 by the road with non-return valve 14, outlet main valve 15 is connected, and first, two dosing pump inlet valves 4,6 and first, two dosing pumps 2, also be separately installed with the first communication valve 11 and the second communication valve 10 between 3, the outlet of the first communication valve 11 and the second communication valve 10 by the road respectively with the second dosing pump 3, the outlet of the first dosing pump 2 is connected, and the outlet of the first communication valve 11 and the second communication valve 10 also reaches by the road and is installed in first on the pipeline, two recycle valves 9,8 are connected with dosing tank 1.
Its use procedure is as shown in the figure:
(1) when the first dosing pump inlet valve 4 (the second dosing pump inlet valve 6), the first dosing pump outlet valve 5 (the second dosing pump outlet valve 7), when outlet main valve 15 is opened, the first dosing pump 2 (the second dosing pump 3) isolated operation dosing, the second dosing pump 3 (the first dosing pump 2) is for subsequent use;
When the first dosing pump inlet valve 4, the first dosing pump outlet valve 5, the second dosing pump inlet valve 6, the second dosing pump outlet valve 7, when outlet main valve 15 is opened, the first dosing pump 2, the 3 parallel running dosings of the second dosing pump;
When the first dosing pump inlet valve 4 (the second dosing pump inlet valve 6), the second dosing pump outlet valve 7 (the first dosing pump outlet valve 5), the second communication valve 10 (the first communication valve 11), when outlet main valve 15 is opened, the first dosing pump 2 and the 3 series operation dosings of the second dosing pump.
(2) when occurring gasifying in the body because of the decomposition of hydrogen peroxide in the first dosing pump 2 dosing processes, close the first dosing pump inlet valve 4, open the first communication valve 11, utilize the second dosing pump 3 that the gas in the first dosing pump 2 is ejected, thereby eliminate its vent plug.
(3) non-return flap 14 can prevent that the alkali lye in the purging system from refunding the rapid decomposition that causes hydrogen peroxide to medicine system.
The present invention passes through ingehious design, but both the using and the reserved of 2 dosing pumps in the electricity testing device, also can parallel connection move simultaneously, can also connect and move simultaneously, the vent plug that can mutually solve the gasification in the pump housing between 2 dosing pumps and cause, apparatus system is reasonable in design, compact in design, construct easyly, maintenance is little.