JPH08105604A - Condensing blow device of boiler using electric conductivity in supply water - Google Patents

Abstract

PURPOSE: To make it possible to follow up not only the flow rate of supply water but also changes in water quality and maintain an optimum blow rate constantly by inputting the electric conductivity of supply water to a condensing blow device and correcting the input value based on a specified equation and controlling the blow based on the corrected blow rate. CONSTITUTION: A water supply tank 3, a water supply pump 4 and an electric conductivity meter 5 are installed on the way of a water supply pipeline 2 connected to the lower part of a boiler 1. The steam generated in the boiler 1 is vapor-liquid separated and the separated liquid is returned into the boiler 1 by way of a water downcomer 8. A solenoid on-off type condensing blow valve 11 is installed on the way of a blow pipeline 9 connected to the lower part of the water downcomer 8. The electric conductivity of the water supply detected with the electric conductivity meter 5 installed on the way of the water supply system is input into a blow control device 13 which controls the opening of the condensing blow valve 11 where the blow rate is corrected based on the equation preliminarily input in the blow control device 13, thereby controlling the electric conductivity so as to conform to the corrected blow rate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concentrating blow device for a boiler which utilizes the electric conductivity of water supply.

[0002]

2. Description of the Related Art Boiler can water is concentrated as it evaporates, causing carryover, and the dryness of steam decreases. Therefore, it is necessary to perform a concentration blow to discharge a part of the canned water to reduce the degree of concentration. Further, the water supplied to the boiler may be injected with a chemical solution in order to prevent corrosion of the water pipe. Since the blow rate and the chemical injection rate differ depending on the water quality, and the water quality varies greatly depending on the water source, the water quality of the feed water is measured in advance and the blow rate and the chemical injection rate determined by the water quality are input to the blow control device and the chemical injection control device. Aside from that, the amount of blow and the chemical injection calculated according to the amount of water supply are performed. However, even if the water comes from the same water source, the water quality is fluctuating, and if the drain recovery rate varies and the feed water quality fluctuates significantly, the appropriate blow rate and chemical injection rate Also fluctuates. However, the control that is actually performed is based only on the first measured water quality, and there is a difference between the appropriate amount and the amount that is actually used, and wasteful blowing or chemical dosing, or blowing or chemical dosing It was causing a shortage.

[0003]

The problem to be solved by the present invention is to provide a blower device capable of always keeping an optimum blow rate by following not only the flow rate of feed water but also the change in water quality.

[0004]

[Means for Solving the Problems] In a boiler that performs a concentrated blow by calculating a concentrated state of canned water by calculation and opening and closing a concentrated blow valve according to a blow rate, the electric conductivity of the supplied water is detected in the middle of a water supply system. An electric conductivity meter is provided, and the detected electric conductivity is input to the blow control device that controls the opening and closing of the concentration blow valve, and the blow rate is corrected based on the formula previously input to the device control device. Blow is performed so as to obtain the corrected blow rate.

[0005]

By constantly detecting the electric conductivity of the feed water and setting the blow rate according to the detected electric conductivity, it is possible to always perform optimum blowing according to the varying water quality.

[0006]

An embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the water supply pipe (2) connected to the lower part of the boiler (1) is provided with a water supply tank (3), a water supply pump (4) and an electric conductivity meter (5) on the way. The injection device (6) is connected to the water supply pipe upstream of the electric conductivity meter. The electric conductivity detected by the electric conductivity meter is
It is sent to the electrical conductivity abnormality detection device (14) and the presence or absence of abnormality is confirmed. Further, the boiler control device (12) connected to the water supply pump, the chemical injection device, the boiler, and the electrical conductivity abnormality detection device has a water supply control unit, a chemical injection control unit, a combustion control unit, etc., and performs each control. . The steam generated in the boiler is sent to the steam-water separator (7) through the steam communication pipe (10) and is separated into gas and liquid to take out only the steam, and the separated liquid passes through the downcomer pipe (8). Returned to the boiler.
An electromagnetic opening / closing type concentration blow valve (11) is provided in the middle of the blow pipe (9) connected to the lower part of the downcomer pipe. Blow control device (13) for controlling the opening and closing of the concentration blow valve
Is connected to an electric conductivity meter abnormality detection device and a boiler control device in addition to the concentration blow valve.

The electrical conductivity meter measures the electrical conductivity of the feed water and outputs the electrical conductivity to the electrical conductivity meter abnormality detection device. The electrical conductivity meter abnormality detection device stores the electrical conductivity within the normal range and the electrical conductivity that was initially detected, and the electrical conductivity detected by the electrical conductivity meter is within the normal range. When it is, the value from the electric conductivity meter is directly output to the blow control device and the boiler control device, and when it is not within the normal range, the stored electric conductivity is output to the blow control device and the boiler control device. . The blow control device to which the electric conductivity is input calculates the blow ratio by the previously input calculation formula, and the boiler control device calculates the chemical injection ratio. The boiler control device measures the combustion state and the combustion time when the boiler is burned, and outputs it to the blow control device. The amount of water supplied to the boiler is equal to the amount evaporated by combustion, and the amount of evaporation can be obtained from the combustion time.Therefore, the amount of water supplied can be obtained from the combustion time. The blow amount is calculated from the water supply amount obtained from the combustion time, and the timing for opening and closing the concentration blow valve is determined. The blow control device opens and closes the concentration blow valve according to the determined opening / closing timing to perform the concentration blow. Also, regarding the chemical injection control, the operation control of the chemical injection device is performed so that the chemical injection rate calculated by the boiler control device is obtained.

It should be noted that the chemical injection device in the above embodiment is not essential, and when the chemical injection device is provided, the electrical conductivity is affected by the chemicals. Therefore, an electrical conductivity meter is provided in the water supply system after the chemicals are supplied. , To detect the electric conductivity of water supply after chemical injection.

[0009]

As described above, according to the present invention, the electric conductivity of the feed water is detected and the blow rate is corrected according to the change in the water quality, so that the blow rate suitable for the water supply at that time can be always selected. Therefore, blow control can be performed without causing insufficient blow or excessive blow. Further, by providing a backup function for maintaining a constant blow rate, it is possible to continue the concentrated blow in a nearly optimal state even if an abnormality occurs in the electric conductivity meter.

[Brief description of drawings]

FIG. 1 is a schematic description of an embodiment of the present invention.

[Explanation of symbols]

 1 Boiler 2 Water supply pipe 3 Water supply tank 4 Water supply pump 5 Electric conductivity meter 6 Chemical injection device 7 Steam separator 8 Downcomer pipe 9 Blow pipe 10 Steam connection pipe 11 Concentration blow valve 12 Boiler control device 13 Blow control device 14 Electric conduction Abnormality detector

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomizo Okada 3-4-15 Hachimancho, Kanonji City, Kagawa Prefecture Samson Inc. (72) Inventor Yasunori Mitsuda 58 Yokoteracho, Shinjuku-ku, Tokyo Kurita BMS Co., Ltd. (72) Inventor Hajime Nakamura 58 Yokodera-cho, Shinjuku-ku, Tokyo Kurita BMS Co., Ltd. (72) Inventor Tetsuji Fujita 58, Yokotera-cho, Shinjuku-ku, Tokyo Kurita BMS Co., Ltd.

Claims (3)

[Claims] 1. A method for calculating the concentration of canned water by calculation,
In a boiler that performs concentration blow by opening and closing the concentration blow valve according to the blow rate, an electric conductivity meter that detects the electrical conductivity of the feed water is installed in the middle of the water supply system, and the detected electrical conductivity is opened and closed. It is input to the blow control device to be controlled, the blow rate is corrected based on the calculation formula previously input to the blow control device, and the blow control is performed by the corrected blow rate. Boiler concentration blower used. 2. The concentrating blow device using electric conductivity according to claim 1, wherein the concentrating blow device for a boiler includes detecting the electric conductivity of feed water after chemical injection. 3. The concentration blowing device using electric conductivity according to claim 1, further comprising an electric conductivity abnormality detecting device for determining whether or not there is an abnormality in the electric conductivity meter. When an abnormality occurs in the boiler, the concentration-blow device of the boiler that stops the correction by the electric conductivity and uses the previously stored normal electric conductivity to blow at a constant blow rate.