JPS6039436B2 - Deoxygenation method and device for water supply - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method and apparatus for deoxidizing feed water.

In recent years, there has been a strong demand for boiler water supply, particularly in high temperature and high pressure boilers, to equalize the oxygen content in the water supply with PP.

On the other hand, there is also a strong demand for reducing the oxygen content in low pressure applications such as 10k9' class. This is because the means for removing impurities in the water supply has been improved, and the problem of oxygen corrosion has appeared because there is less scale than in the past, which had a large amount of scale and a layer of scale adhesion that prevented oxygen corrosion. be. Conventionally, oxygen contained in water supply has been removed using chemicals.
Sodium sulfite, which is used as one of the chemicals, decomposes more easily as the pressure and temperature increase, thereby generating S02 gas, which is oxidized in the superheater and becomes S03 as steam condenses in the low pressure stage of the turbine and S04 This causes problems in that it not only corrodes the members of the low pressure stage but also lowers the pH value of the condensate, contributing to system corrosion. Furthermore, hydrazine (N2day4) has been widely used as a preferred oxygen scavenger because it reacts with oxygen to form water and nitrogen as shown in the following formula. N2 ratio +02 = 2 days 20 ten N2
...m However, N2 Day 4 is toxic to people with unique constitutions, so caution is required.

In addition, this hydrazine must be supplied at a rate slightly higher than the calculated theoretical value in order to reduce the amount of oxygen contained in the water supply, and the excess hydrazine will either evaporate as it is, or convert into ammonia as shown in equation [2}. and decomposes into nitrogen.

Shu 2bon → 4NH30N2...
{2) The ammonia generated here enters the condensate and makes the PH value of the condensate high, and if there is too much ammonia, there is a problem that it corrodes copper-based metals.

In any case, proper control of the supply amount is strongly required in the deoxidizing means due to the use of chemicals, and the problem of corrosion of parts still occurs in the water supply system and the condensate system. The purpose of this invention is to propose a new deoxidation method and device for supplying low-pressure hydrogen gas into water supply to easily and efficiently remove oxygen from water.

However, even if hydrogen gas, which is a gas, is simply supplied into the water supply to remove oxygen from the water supply, it will not dissolve sufficiently into the water supply, and will not react sufficiently with the oxygen in the water, resulting in a large amount of deviated water. The handling of hydrogen cylinders requires the supervision of a responsible person, and handling heavy cylinders is not easy.

This invention makes it possible to supply a stable specific gas from a low-pressure vessel, thoroughly mix it with the feed water, and then pass the feed water through a bed of a suitable catalytic resin for its catalytic action. The present invention is characterized by proposing a method and an apparatus for continuously carrying out operations for sufficiently removing 02.

An apparatus according to the present invention will be explained below with reference to the drawings.

If you try to supply hydrogen gas from a hydrogen cylinder, the high-pressure hydrogen cylinder has an internal pressure of 150k9/cmg, and the cylinder that can withstand that pressure has to be thick, and each cylinder is heavy, and there is a risk of high pressure. It is more difficult to handle than it is a physical object. Also, in liquid hydrogen -253oo
In order to turn something into a gas at room temperature and low pressure, there are many attached devices that are difficult to handle. The inventors focused on the storage capacity of recently developed hydrogen storage alloys and created an invention using this.

FIG. 1 is a diagram of a pipe system for connecting equipment according to the present invention. Reference numeral 1 is a hydrogen storage container. FIG. 2 is a vertical cross-sectional view of the container, which can withstand an internal pressure of 20 to 30 k9/g, and may be made of a material that makes the container lighter, such as AI or AI alloy. The diffusion plate 3 is positioned between the flange of the trunk body la and the flange of the hemispherical lower lid lb forming the bottom pressure chamber 2. The diffusion plate 3 is a porous plate that prevents the hydrogen storage material (powder, small lump form) 4 housed in the eye from leaking into the bottom pressure chamber 2 and allows hydrogen gas to pass through.
made of porous ceramic material, bonded metal plate or metal plate with small holes). Further, the diffusion plate may be a canvas made of heat-resistant (resistant to up to 120 CO) synthetic fibers having a wire mesh on its outer surface. A substantially hemispherical upper lid lc is flange-connected to the upper flange of the barrel. The flange surface uses airtight packing and airtight material to create a structure that prevents hydrogen leakage. If necessary, the periphery of the flange connection portion may be sealed and welded. In addition, there is a heat transfer coil 5 in the same la.
The temperature inside the coil is adjusted by passing hot water, steam, cooling water, or cooling gas through the heat transfer coil. Further, the temperature is measured by the temperature transmitter 6, and the temperature signal is sent to the control box 12 and can be displayed on the instrument. Hydrogen is supplied and stored in the hydrogen storage material in the hydrogen storage container 1 from a hydrogen source such as a hydrogen cylinder 7 via a pressure reducing valve 8 and a valve 9 connected to the lower lid, and further through a pressure chamber 2 and a diffusion plate 3. . Although only one hydrogen storage container 1 is shown in FIG. 1, two or more hydrogen storage containers 1 are installed in parallel (only the outlet valves 11b and 11c of the hydrogen storage container are shown), and a hydrogen gas supply main pipe (hereinafter simply referred to as the hydrogen main pipe) is provided. ) 10, and the outlet valves 11a, 11b of the hydrogen storage container
, 11c can be switched in response to a command signal from the control box 12 that outputs a memory and command signal or by manual operation to continuously supply hydrogen gas to the deoxidizing container 34. The pressure inside the hydrogen storage container 1 is sent to the control box 12 as a pressure signal from a pressure gauge 13 connected to the upper lid lc. Hydrogen storage container 1
Hydrogen gas with a pressure of 20 to 30 k9/g is removed from the outlet valve 11.
The pressure is reduced from the hydrogen main pipe 10 through the pressure reducing valve 14 from a to 5 to 8.
The hydrogen gas has a hydrogen release pressure of k9/g. The adjustment can be done manually by visually observing the pressure transmitters 15a, 15b installed in the main hydrogen pipe 1 before and after the pressure reducing valve 14, or by controlling the control box 1 which receives signals from these pressure transmitters 15a, 15b.
It is controlled by a command signal from 2. The reduced pressure hydrogen gas passes through the hydrogen gas flow meter 16 and the stop valve 25 and is supplied to the hydrogen feed water mixer 17 . An example of the hydrogen supply water mixer (hereinafter simply referred to as mixer) 17 has a structure whose cross section is shown in FIG.

The water supply W includes a water softener 18, a soft water tank 19, and a water supply pump 2.
0, the water is supplied to the mixer 17 via a water supply pipe 21, a water supply flow rate control valve 22, and a water supply flow meter 23. In addition,
The soft water tank or water supply pipe 21 is provided with an 02 meter 24 for measuring 02 in the supplied water, and the 02 content in the supplied water is displayed on the meter and sent as a signal to the control box 12. The structure of the mixer 17 will be explained with reference to FIGS. 3 and 4.

The mixer 17 includes a venturi section 17a and a baffle mixing section 1.
7b and more. In order to increase the amount of gas dissolved into water, it is preferable that the water temperature of Hirogasu is 5,000 degrees Celsius or less. Figure 5 shows water/skin 1 at a pressure of 76 degrees.
It is a diagram showing the volume of day 2 dissolved in water at 0° C., the value a (Bunsen absorption coefficient) x 1, which is converted into a solar cell of 76 days, on the vertical axis, and the temperature on the axis.

Regarding pressure, Hen's law states that ``When the temperature is constant, the solubility of a gas in a given amount of liquid is directly proportional to the partial pressure of that gas.'' The higher the pressure, the better the solubility. Therefore, a container pressure of 20 to 30k9/g is selected based on the container's H storage material capacity, wall thickness, price, etc.
It is best to use it under reduced pressure to ~8k9/g of lump. This 5~
The pressure is reduced to 8k9/g, and the gas is supplied from the main hydrogen pipe 10 via the stop valve 25 to the air chamber 26 of the venturi section 17a, and is supplied into the water supply through a plurality of holes 28 provided in the throw section 27 of the venturi. It mixes with the water supply, forming fine bubbles. On the other hand, the water supply enters the venturi section 17a from the pipe 21, receives the gas supplied twice a day at the slow section 27, mixes with this gas, and flows to the baffle mixing section 17b, where it flows into the baffle 29.
Due to the resistance, the flow becomes turbulent and mixes well with the specific gas.
Via the main flow control valve 31 and the water supply spray supply device 32, the Q in the water is ejected from the plurality of nozzles 32a provided in the water supply light mist supply device 32 into the supply water in the deoxidizing container 34 having the catalytic resin layer 33. It makes good and sufficient contact with the catalyst, passes through the catalyst layer, reacts with 02 due to its catalytic action, and becomes water (day 20)-, which is deoxidized. This deoxygenated feed water is supplied to the flow control valve 3
5. Pipe line 38 via water pump 36 and water flow meter 37
The water is supplied to boilers and other equipment that require water. Next, the hydrogen storage material accommodated in the hydrogen storage container 1 will be explained.

The recently developed TIMn alloy is an extremely preferable material in terms of storage capacity and handling. The behavior of hydrogen during hydrogen storage is △day is the calorific value of 7. Dish cal/day 21mol
It is.

TIMn,. 54.47 takes the form of a solid solution, and has the property of becoming fine powder particles when it releases hydrogen, and becoming granular and small-sized when it absorbs hydrogen. In experiments, no decrease in storage capacity was observed even after occluding and releasing two gases per day several thousand times (6,000 times). The properties of the TMn alloy as the hydrogen storage material are as follows.

{i}Hydrogen storage capacity Alloy 180-220 per evening
1.134 to 1.386 cc per cclcc (〇｝ Hydrogen release rate Average total %) Hydrogen release pressure 5 to 8 atm (20 to 40 C) 6th
The figure shows TMn,. FIG. 2 is a diagram showing the relationship between temperature and hydrogen release pressure for TiFe and TiFe-day.

By using such hydrogen storage materials, it is extremely easy to supply hydrogen at room temperature, the amount of hydrogen stored is relatively large, and it is possible to release hydrogen at almost constant pressure at room temperature. The present invention also provides a feed water deoxidizer with advantages such as being relatively inexpensive.

The first for the fluid flowing into the heat transfer coil 6 in the hydrogen storage container 1.
This will be explained using figures. Heated fluid such as steam, hot water, hot gas, etc. passes through a pipe 39 and a flow rate control valve 39a to the mixer 4.
A cooling fluid such as cold water is supplied to a mixer 44 via a pipe 40 and a flow control valve 40a and mixed to obtain a fluid at a controlled temperature, and the temperature is confirmed with a thermometer 43. Thereafter, it is supplied to the heat transfer coil 5 from the conduit 41 via the flow rate control valve 42. The temperature of the hydrogen storage material 4 in the hydrogen storage container 1 is adjusted to an appropriate temperature, and the hydrogen storage material 4 is discharged via a pipe 45 and a valve 46. The heated fluid is supplied separately through the pipe 41 when releasing the stored specific gas, and the cooling fluid is supplied separately through the pipe 41 during the hydrogen storage process, and flows through the mixer without mixing. It's okay. The reason why the diffusion plate 3 is provided in the hydrogen storage container is that since the hydrogen storage material before hydrogen storage is in the form of fine powder, the hydrogen gas supplied from the hydrogen cylinder 7 causes the fine powder in the container to form a fluidized bed. The area of contact with hydrogen gas is large, and the hydrogen gas is brought into uniform contact with hydrogen gas, resulting in the effect of significantly shortening the storage time.

Next, deoxidation, which is the reaction between days 2 and 02 in the deoxidizing container 34, will be explained.

This device has a structure similar to a commonly used container using ion exchange resin. An ion exchange resin layer 33 is located on a perforated plate 34a (resin receiving plate) inside the container, and an ion exchange resin supply port (which may also be used as a manhole) 34b and a hydrogen gas release valve 47 are located on the upper end plate.
(The released gas is reused for deoxygenation.) A safety valve 48, a pressure gauge 49, a backwash nozzle 50, and a stop valve 51 are provided. A water supply discharge nozzle 52 and a main conduit 54 for deoxygenated water supply connected to the water supply discharge nozzle 52 are provided on the lower end plate. Stop valves 53a and 53 are provided in the pipe line 55 branching from the main pipe line 54.
b, and a backwashing pipe 56 is provided which connects to the pipe 55 between the two stop valves. The ion exchange resin used is a catalytic resin that mainly performs this deoxidation, and is a gel type strongly basic type 1 anion exchange resin. This reaction occurs on the surface of a catalyst resin to which palladium has been added, and has a special effect on deoxidizing an aqueous solution. One example is the trade name Revachit OCI045. Stable operating temperature is 10
The temperature shall be below 0℃. In tests and experiments using this device to supply hydrogen-containing water, it was confirmed that when the amount of hydrogen supplied was slightly less than its stoichiometric amount, the amount of residual oxygen increased.

Figure 7 shows the experimental results.The amount of residual oxygen when supplying more than the chemical theoretical amount is shown by a diagram with the symbol A, and when it is slightly less than the chemical theoretical amount, the residual oxygen amount is shown by the diagram with the symbol A. B
It becomes a line diagram of a castle, and if it is further reduced, it becomes a line diagram of castles C and D.
When a slightly higher ratio than the chemically stoichiometric amount was supplied to this, the residual P2 weight rapidly decreased, as shown by symbol E, and its rapid effect was confirmed. Also, it goes without saying that the slower the water supply rate BV/h passing through the catalyst resin layer (Gono 100 water/h/resin layer), the more effective the deoxidation is, as shown in FIG. FIG. 9 shows a control system according to the embodiment of the present invention.

The symbols of the equipment members correspond to those in FIG.
As mentioned above, for suitable removal of 02 in water, it is necessary to supply a specific gas amount greater than the stoichiometric amount per day corresponding to this amount of 02. Therefore, the amount of 02 in the supplied water is obtained by sending the flow rate signal of the water supply flow meter 23 and the 02 base signal of the 02 meter 24, which measures the 02 in the water supply, to the control box 12 and multiplying them. The two daily amounts required for this are the flow rate signal of the hydrogen gas flow meter 16 and the pressure signal of the pressure gauge 15b in the control box 1.
2 and is calculated. The pressure of the hydrogen gas sent to the mixer 17 is determined by a pressure gauge 13 that measures the pressure inside the hydrogen storage container 1.
The signals from the pressure transmitters 15a and 15b are transmitted to the control box 1.
2 and is regulated by controlling the pressure reducing valve 14. In addition, by switching the outlet valves 11a, 11b, and 11c, the delivery of gas twice a day can be made continuous, while
Capable of gas storage operations. As shown in the diagram in FIG. 6, the gas pressure in the hydrogen storage container 1 is determined by the temperature of the temperature transmitter 6 and the amount of gas sent out, so the flow rate signal of the hydrogen gas flow meter 16 and the temperature signal The temperature signal from the thermometer 43 is sent to the control box 12, and the temperature of the fluid flowing through the heat transfer coil is determined by the flow rate control valves 39a, 40a based on the signal from the thermometer 43.
By adjusting and controlling the amount of specific gas generated, the amount of specific gas generated is determined, and the result is controlled to be displayed on the pressure gauge 13. The amount of water supplied to the mixer 17 is controlled by a water supply flow rate control valve 22 .

The amount of water to be fed is adjusted by sending a signal of the remaining 02 amount from the 02 meter 57 and a signal from the water flow meter 37 to the control box 12 and controlling the valve 35 and/or the main flow control valve 31.

Further, a load signal (not shown) of the device to which the deoxygenated feed water is supplied can be input into the control box 12 and added as a factor for controlling the device. By practicing this invention, the appropriate amount of day 2
Since the gas is supplied to the deoxidizing vessel 34 together with the water supply and has a ratio of ○ in the catalyst resin layer 33, there is no corrosion of the water supply system of the boiler or the turbine plant, and the ratio of the gas supply device is 20.
It is possible to use a low-pressure product of ~30k9/kg class, it is easy to control the storage and release of two gases per day, the storage metal material can be used repeatedly, and the deoxidation reaction can be achieved in a short time. It has various effects such as eliminating the need for oxygen scavenging agents such as.

[Brief explanation of the drawing]

FIG. 1 is a drawing showing the piping system of the device according to the present invention;
Figure 2 is a cross-sectional view of the hydrogen storage container, Figure 3 is a vertical cross-sectional view of the mixer, Figure 4 is a 1-1 cross-sectional view of Figure 3, and Figure 5 is the water temperature regarding the solubility of H gas in water. FIG. 6 is a diagram showing the relationship between the B plate sen absorption coefficient and the TIMnl. A diagram showing the relationship between temperature and hydrogen release pressure for the porridge alloy and the TiFe-N alloy. C, D)
Figure 8 is a diagram showing the relationship between the flow rate in the deoxidizing container and the residual oxygen in the treated water, and Figure 9 is shown in Figure 1. FIG. 3 is a control system diagram of the device. 1... Hydrogen storage container, 11a, 11b, 11c.・・・
Outlet valve, 12... Control box, 14... Pressure reducing valve, 17.
... Mixer, 20 ... Water supply pump, 31 ... Main flow control valve, 34 ... Oxygen removal container, 36 ... Water supply pump. Figure 3 Figure 4 Figure 1 Figure 9 Figure 2 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] 1. A water supply characterized in that hydrogen supplied from a pressure vessel containing a hydrogen storage material via a pressure reducing valve is mixed with water supply and supplied to a container containing a catalyst resin to deoxidize it. Deoxidation method. 2. The method for deoxidizing feed water according to claim 1, characterized in that the hydrogen storage material is a TiMn-based alloy, and the catalyst resin is a coarse anion exchange resin to which palladium is added. 3. Claim 1 or 3, characterized in that the oxygen content in the supplied water is measured before it is mixed with hydrogen, and hydrogen is supplied in an amount that is less than the stoichiometric amount to react with the oxygen content to form water. The method for deoxidizing feed water as described in Section 2. 4. Hydrogen storage container with a built-in heat transfer coil that can switch or mix heating and cooling fluids to supply the appropriate temperature and containing hydrogen storage material, pressure reducing valve, hydrogen gas flow meter, hydrogen supply water mixer The hydrogen-containing supply pipe, which connects the water supply tank, main flow rate control valve, and water supply spray supply device located inside the deoxidation vessel, with the water supply tank, water supply pump, water supply flow rate control valve, and water supply flow meter, 1. A water supply water deoxidizing device comprising: a water supply pipe connected by a pipe having a meter; and a deoxidizing container incorporating the water supply spray supply device and having a catalyst resin layer. 5. A ventilary unit that receives water supply from the hydrogen supply water mixer, a hydrogen gas chamber that supplies hydrogen gas from a nozzle provided at the throat of this ventilary unit to the throat, and a ventilary unit that is connected to this ventilary unit and has one or more baffles. 5. A deoxidizing device for feed water according to claim 4, characterized in that the device is connected to a mixing chamber. 6 Hydrogen storage container, pressure reducing valve, hydrogen gas flowmeter, hydrogen supply water mixer, which has a built-in heat transfer coil that can switch or mix heating fluid and cooling fluid to supply the appropriate temperature, and also contains hydrogen storage material. , the main flow rate control valve, the hydrogen-containing water supply pipe that connects the water supply spray supply device located in the deoxidizing container with a pipe, the water supply tank, the water supply pump, the water supply flow rate control valve, the water supply flow meter, and the supply water temperature. In a feed water deoxygenation device comprising a water supply pipe connected by a pipe having a meter and a deoxidation container incorporating the feed water spray supply device and having a catalyst resin layer, the hydrogen gas pressure supplied from the hydrogen storage container is A control box is provided that receives the signal of the pressure difference before and after the pressure reducing valve, the flow rate signal of the hydrogen gas flow meter, the residual oxygen amount signal of the deoxygenated feed water, and the flow rate signal of the water supply flow meter, and outputs a command signal. A water supply control system is installed to control the outlet valve of the hydrogen storage container, the pressure reducing valve, the main flow control valve for the supply water mixed with hydrogen, the supply water flow control valve for the supply water before hydrogen mixing, and the flow control valve for the deoxygenated feed water. A water supply water deoxidizer characterized by: 7. The water supply according to claim 6, characterized in that the temperature inside the hydrogen storage container is sent as a temperature signal to a control box, and the temperature-adjusted fluid is supplied to a heat transfer coil provided inside the hydrogen storage container. Oxygen absorber.