JPH06170357A - Method for stabilizing dissolved oxygen concentration in deaerator - Google Patents

Abstract

PURPOSE:To stabilize the concentration of dissolved oxygen in deaerated water to be treated at a specified level in a deaeration. CONSTITUTION:A deaerated water supply line 3 consisting of a temperature sensor 4, a water supply pump 5 and a deaerator 6 which removes dissolved air from untreated water, all introduced into the line 3, is connected between an untreated water supply part 1 and a deaerated water tank 2 with a water level detector. Further, a controller 8 is provided which controls the operation of the water supply pump 4 and the deaerator 6. Further, the supply amount of untreated water to be supplied to the deaerator 6 is adjusted based on signals on the temperature of untreated water from the temperature sensor 4 and from the water level detector in the deaerated water tank 2. Thus the deaerated water of a specified concentration of dissolved oxygen is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for stabilizing the dissolved oxygen concentration in a deaerator applied to a heat equipment such as a boiler or a water supply line to a building, a condominium or the like.

[0002]

2. Description of the Related Art As is well known, a water supply line for cooling and heating equipment such as a boiler, a water heater or a cooler is equipped with a deaerator for the purpose of preventing internal corrosion of these equipment. Further, in recent years, deaeration devices have come to be used as a measure for preventing red water in water supply and distribution pipes in buildings, condominiums, and other structures. In this deaerator, a membrane deoxygenation module is connected in the water supply line to the equipment used, and raw water (tap water, well water, other industrial water) is passed through this deoxidation module, In the water process, the inside of the deoxygenation module is evacuated to degas the dissolved gas in the raw water.

By the way, the deaerator has a characteristic that, as shown in FIG. 2, if the amount of treated water is constant, the dissolved oxygen concentration of the treated water increases as the temperature of the raw water supplied decreases. Therefore, the dissolved oxygen concentration is low in the summer when the water temperature is high, and the dissolved oxygen concentration is high in the winter when the water temperature is low. It's a problem.

[0004]

In view of the above problems, the present invention detects the water temperature of the raw water to be supplied, determines the water temperature and adjusts the supply amount of the raw water to be supplied to the degassing device, It is an object of the present invention to provide a method for stabilizing the dissolved oxygen concentration of.

[0005]

That is, according to the present invention, between a raw water supply section and a degassed water tank equipped with a water level detector,
A temperature sensor, a water supply pump, and a degassing water supply line for removing dissolved gas in raw water are connected to the degassed water supply line, and a controller for controlling the operation of the water supply pump and the degassing device is provided. Based on the raw water temperature and the signal from the water level detector in the degassed water tank, the amount of raw water supplied to the degassing device is adjusted to ensure degassed water with a predetermined dissolved oxygen concentration. I am trying.

[0006]

According to the present invention, the temperature sensor detects the water temperature of the raw water and reports it to the controller, and the water level detector in the degassed water tank reports the water level signal to the controller, and the controller presets. In order to ensure the dissolved oxygen concentration in the degassed water, the flow rate of the feed water pump is controlled by distinguishing the water temperature, the treated water amount and the water level signal, and the amount of raw water to be supplied to the deaerator is adjusted to obtain the predetermined dissolved oxygen concentration. Supply deaerated water.

[0007]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is an explanatory view showing the arrangement of each device in a degassed water supply line 3 embodying the present invention. The raw water supply unit 1 and the deaerated water tank 2 of the deaerated water supply line 3
A temperature sensor 4, a water supply pump 5 and a deaerator 6 are connected between the and. In the degassed water tank 2, a lower electrode rod L, a middle electrode rod M, and an upper electrode rod S for water level detection are inserted, and each electrode rod L, M, S connects a line 7. A water level detection signal is sent to the controller 8 via the above. The temperature sensor 4 detects the temperature of raw water and outputs an electric signal to the controller 8 via the line 7. Further, the water supply pump 5 is of a variable flow type, and the controller 8 determines the raw water temperature signal from the temperature sensor 4,
The raw water supply amount (processed water amount) (see FIG. 3) corresponding to the preset dissolved oxygen concentration is degassed by the signal from the controller 8
Supply to.

The deaerator 6 has a deoxygenation module connected in the deaerated water supply line 3 and allows raw water to pass through the deoxygenation module. Is evacuated to remove the dissolved gas in the raw water by degassing. In this type of deaerator 6, a water-sealed vacuum pump (not shown), which has a simple structure and is inexpensive, is used as a means for vacuuming. The degassed water that has been degassed flows into the degassed water tank 2 and is supplied to each device from the bottom of the degassed water tank 2 through the treated water supply line 9.

Next, the operation of the method for stabilizing the dissolved oxygen concentration in this deaerator will be described. When the raw water is supplied from the raw water supply unit 1 (for example, the raw water tank) to the degassed water supply line 3 by driving the water supply pump 5, the temperature sensor 4 detects the temperature of the raw water and an electric signal is sent via the line 7 to the controller. Output to 8.
The controller 8 determines the raw water temperature signal from the temperature sensor 4, and determines the dissolved oxygen concentration (0.5 pp) in the degassed water set in advance.
m), the amount of raw water that can be treated by the deaerator 6 is set based on the preset numerical value of the relation between the raw water temperature and the amount of treated water (see FIGS. 2 and 3). Is adjusted to supply degassed water having a predetermined dissolved oxygen concentration to the degassed water tank 2. Then, when the deaerated water reaches the upper electrode S of the deaerated water tank 2, the water supply pump 5 and the deaeration device 6 are stopped. Degassed water is supplied to each device through a treated water supply line 9 connected to the bottom of the tank. When the water level in the degassed water tank 2 cuts off the middle electrode rod M, a water pump 5 and the deaerator 6 are driven to supply deaerated water to the deaerated water tank 2 according to the initial procedure. When the supply of degassed water is temporarily increased compared to the supply of degassed water and the lower electrode rod L is cut off, the controller 8 operates the water supply pump 5 at the maximum flow rate regardless of the water temperature of the raw water to perform emergency water replenishment. To do. Then, when the water level reaches the lower electrode rod L, the normal operation is restored to the conventional one so that the treated water having a predetermined dissolved oxygen concentration can be supplied.

In the above-described embodiment, the water supply pump 5 is of a variable flow rate type, but this is an ordinary commercial pump, and an inverter capable of converting the frequency by the electric signal of the temperature sensor 4 is provided in the controller 8. However, it is also possible to adjust the amount of raw water supplied to the deaerator 6 by connecting a pump to the inverter via the line 7 and converting the motor speed of the pump.

Next, an embodiment replacing the above embodiment will be described with reference to FIG. As shown in FIG. 3, the degassed water supply line 3
A bypass line 10 is provided with the water supply pump 5 inserted between the bypass line 10 and the electric operation valve 11 inserted into the bypass line 10.
The operation valve 11 is connected to the controller 8 via the line 7. The water supply pump 5 is an ordinary commercially available pump, and in order to secure a predetermined dissolved acid concentration (0.5 ppm) of the degassed water preset by the electric signal of the temperature sensor 4, the raw water temperature and the deaerator 6 are set. The controller 8 sends a signal to the operation valve 11 to open the valve based on the relational value with the amount of treated water, and causes a part of the raw water to flow into the bypass line 10 to supply the raw water to the deaerator 6. Is adjusted to a predetermined amount of water and supplied. The structure and operation other than those described above are the same as those of the above-described embodiment, and thus the description thereof is omitted.

[0012]

As described above, according to the present invention, in order to secure a preset dissolved oxygen concentration (0.5 ppm) in degassed water, a temperature sensor is inserted in the degassed water supply line,
This temperature sensor detects the water temperature of raw water and reports it to the controller.The controller adjusts the flow rate of the water supply pump based on the preset numerical value of the relation between the raw water temperature and the treated water amount of the deaerator. Since a prescribed amount of raw water is supplied to the degassed water, a prescribed concentration of deaerated water can be obtained. In addition, in case of a temporary increase in degassed water, it is safe because the water supply pump can be temporarily fully operated for emergency water supply.

[Brief description of drawings]

FIG. 1 is an explanatory view showing the arrangement of each device in a degassed water supply line showing an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between raw water temperature, treated water-soluble oxygen concentration and treated water amount in a deaerator.

FIG. 3 is a diagram showing the effect of raw water temperature on treatment with a dissolved oxygen concentration of 0.5 ppm.

FIG. 4 is an explanatory diagram showing an arrangement of each device in a degassed water supply line showing an embodiment replacing the embodiment of FIG.

[Explanation of symbols]

 1 ... Raw water supply part 2 ... Deaerated water tank 3 ... Deaerated water supply line 4 ... Temperature sensor 5 ... Water supply pump 6 ... Deaeration device 8 ... Controller L ... Lower electrode rod M ... Middle electrode rod S ... Lower electrode rod

Claims (1)

[Claims] 1. A temperature sensor 4, a water supply pump 5, and a degassing device 6 for removing dissolved gas in raw water are inserted between a raw water supply unit 1 and a degassing water tank 2 equipped with a water level detector. Is connected to the deaerated water supply line 3 and a controller 8 for controlling the operation of the water supply pump 4 and the deaeration device 6 is provided, and the raw water temperature from the temperature sensor 4 and the water level detector in the deaerated water tank 2 are provided. A method for stabilizing the dissolved oxygen concentration in a degassing device, characterized in that the amount of raw water supplied to the degassing device 6 is adjusted based on a signal from the device to ensure degassed water having a predetermined dissolved oxygen concentration.