JP3667033B2 - Iron analyzer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an iron analyzer for measuring and analyzing the concentration of iron in sample water collected from system water of a plant such as a thermal power plant.
[0002]
[Prior art]
If the concentration of iron in the system water flowing through the plant piping exceeds the specified value, problems such as iron adhesion to the inside of the piping, etc. and increased pressure loss can be assumed, and the end of the cleanup process at startup In a plant such as a thermal power plant, the system water is collected and the iron concentration is measured and analyzed by an iron analyzer.
[0003]
For this type of iron analyzer, an analysis method defined by JIS is usually used. That is, by adding a solvent such as hydrochloric acid to sample water collected in a batch mode and heating it, the insoluble iron content in the sample water is dissolved to ionize all the iron, and this is added with the specified chemicals. In this method, the colored sample water is irradiated with light of a specific wavelength, and the iron concentration is measured by the Lambert-Pale law by light absorption that occurs while passing through the sample water layer of a predetermined width. is there.
[0004]
By the way, the sample water sampling method in such a conventional iron analyzer is obtained by collecting the system water of the plant piping in a container as sample water and bringing it to the place where the iron analyzer is installed, or iron analysis This is an offline method in which the sample piping is drawn from the plant piping to the container placed near the device, sample water is collected in the container, and the sample water in the container is pumped up and introduced into the iron analyzer. It was. As this pump, a plunger type pump has been used in order to ensure a predetermined constant flow rate and constant pressure.
[0005]
[Problems to be solved by the invention]
However, when collecting a sample containing particulate iron, if the plunger pump as described above is used, the particulate iron in the sample water cannot be collected uniformly, and the particulate iron in the sample water tend to pump life seal is extremely short, when there are more bubbles in the sample water, there is a problem that the pump discharging becomes unstable by airlock.
[0006]
This invention is made in view of such a point, The objective is to provide the iron content analyzer which enabled it to extract | collect sample water continuously.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the first aspect of the present invention includes a sample water intake means for collecting sample water from a plant to obtain sample water, and sample water delivered from the sample water intake means. A dissolution means for injecting a solubilizer into the sample water to dissolve the particulate iron in the sample water, a reaction means for injecting a reaction liquid into the sample water sent from the dissolution means and reacting with the iron content, and from the reaction means In an iron content analyzer comprising iron content detecting means for detecting the iron content concentration of the sample water sent out,
The sample water intake means includes a sample water cutting device for connecting the first pipe and the second pipe,
The sample water cutting device is:
A sample water introduction pipe for introducing the sample water, a sample water outlet pipe for discharging the sample water from the sample water cutting device, and a carrier supply pump capable of supplying the carrier from the storage tank of the carrier; Set the inner diameter and length of the second pipe equal,
A first switching state in which the first pipe communicates with the sample water introduction pipe, and one end of the second pipe communicates with the carrier supply pump, and the other end of the second pipe communicates with the sample water outlet pipe; and the sample water introduction pipe To the second switching state in which one end of the first pipe communicates with the carrier supply pump, and the other end of the first pipe communicates with the sample water outlet pipe.
In the first switching state, the sample water is introduced into the first pipe, the carrier is supplied to the second pipe, and the sample water introduced in the second switching state is discharged.
In the second switching state, the sample water is introduced into the second pipe, and the carrier is supplied to the first pipe to discharge the sample water introduced in the first switching state.
The iron analyzer is characterized in that the state of the sample water cutting device is changed while the carrier is filled in the first pipe or the second pipe.
[0008]
A second aspect of the present invention is the iron analyzer according to the first aspect, wherein the sample water flowing through the sample water introduction pipe is set to a flow velocity at which the Reynolds number becomes a turbulent flow region.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below. FIG. 1 is a block diagram showing the configuration of the iron content analysis apparatus according to the embodiment. Reference numeral 1 denotes a system water pipe of a plant such as a thermal power plant. In this embodiment, the system water (steam / condensate / feed water, etc.) of this pipe 1 is reduced in temperature by, for example, 35 ° C. The pressure is adjusted to about 3 kg / cm ² and taken in as sample water. 3 is a flow meter for measuring the flow rate of the sample water per unit time, and 4 is a pressure relief valve for adjusting the pressure of the sample water introduction pipe 5 to a predetermined pressure. Reference numeral 6 denotes a sample water cutting device, which is composed of an 8-way valve in which the internal rotor rotates / returns 45 degrees to switch the valve. The sample water intake means is configured as described above.
[0010]
As shown in FIG. 2 in an enlarged manner, the sample water cutting device 6 adjusts the rotational position of the internal rotor so that each of the valve ports AB, CD, EF, GH A switching state (corresponding to the first switching state in the present invention ) connecting between the valve ports BC, DE, FG, and HA (connected with a broken line) The switching state (corresponding to the second switching state in the present invention) can be selected (that is, the state is converted) . The sample water introduction pipe 5 is introduced into the valve port A, the carrier (conveying liquid) is introduced from the valve port G, the valve port C is connected to the sample water outlet pipe 7, and the valve port E is connected to the drain pipe 8. It is connected. The valve ports BF are connected by a pipe 6a (corresponding to the first pipe in the present invention) , and the valve ports DH are connected by a pipe 6b (corresponding to the first pipe in the present invention) . The pipes 6a and 6b have the same inner diameter and length, and determine the amount of sample water cut off.
[0011]
9 is a storage tank for a carrier (for example, pure water), 10 is a storage tank for a dissolving agent (for example, hydrochloric acid), 11 is a storage tank for a reducing agent (for example, 10% solution of hydroxylamine hydrochloride, etc.), and 12 is an ionized iron content. On the other hand, a storage tank for a color developing agent (for example, a TPTZ 0.001 mol / l solution) that develops a specific color, and 13 is a storage tank for a pH adjusting buffer (for example, a 50% ammonium acetate solution). Each is connected to pumps 19 to 23 via deaeration devices 14 to 18 for bleeding air. Since the deaeration devices 14 to 18 are used in this way, air is not sucked into the pumps 19 to 23, and a plunger type can be used as the pumps 19 to 23. A discharge side pipe of a pump 19 (corresponding to a carrier supply pump in the present invention) is connected to the valve opening G of the sample water cutting device 6 described above, whereby the carrier is supplied thereto at a predetermined flow rate.
[0012]
A dissolving agent is injected into the sample water outlet pipe 7 at the valve port C of the sample water removing device 6 by a pump 20, and thereby the particulate iron in the sample water is dissolved. 24 is a heating apparatus utilizing microwaves or the like, dissolving agent to promote a chemical reaction of dissolution of particulate iron in the injected sample water, heating the water sample, for example, about 150 degrees Celsius. 25 is a cooling device for cooling the sample water heated by the heating device 24 to a predetermined temperature (for example, 25 degrees Celsius), and 26 is a constant internal temperature (for example, 25 degrees Celsius) so as to keep the reaction temperature constant. It is a constant temperature device kept at
[0013]
In this thermostatic device 26, the reducing agent from the pump 21, the coloring agent from the pump 22, and the buffering agent from the pump 23 are sequentially injected into the sample water sequentially sent through the piping, and the reaction coils 27 and 28 are respectively injected. 29, various chemical reactions are carried out at a constant temperature.
[0014]
A spectrophotometer 30 irradiates the processed sample water conveyed from the thermostat 26 with light having a wavelength corresponding to the color of the color former, and measures the iron concentration based on the degree of light absorption. 31 is a back pressure coil (throttle) for stabilizing the chemical reaction and measurement.
[0015]
Next, the operation will be described. In the present embodiment, an on-line method is adopted in which the sample water is directly taken from the piping 1 of the plant system water via the temperature reducing and depressurizing device 2. By setting the sample water within 5 so that the Reynolds number of the sample water is in a turbulent region), the particulate iron can be evenly distributed in the water, and no pump is required for sampling the sample water. It has become. Therefore, various inconveniences caused by using the pump as in the prior art can be avoided.
[0016]
In addition, the sample water cutting device 6 of the present embodiment is a device that cuts sample water introduced from the sample water introduction pipe 5 by a specified amount and sequentially conveys it to the subsequent stage, and there is a carrier between the cut sample waters. No more intervention. That is, when the rotor of the sample water cutting device 6 is currently in the switching state (first switching state) shown in FIG. 1 and FIG. 2, the sample water from the sample water introduction pipe 5 is the valve port A → the valve port B. Since the pipe 6a, the valve port F, the valve port E, and the drain pipe 8 flow (that is, the sample water introduction pipe 5 and the pipe 6a communicate with each other) , the pipe 6a is filled with the sample water.
[0017]
Here, when the rotor is rotated to switch to the broken line state in FIGS. 1 and 2 (converted to the second switching state) , the carrier from the pump 19 changes from the valve port G to the valve port F to the pipe 6a (that is, sample water). The sample water filled in the pipe 6a flows through the valve port B → the valve port C, and the sample water is pressed into the pipe 6a (that is , the direction opposite to the direction of introduction) (that is, one end of the pipe 6a communicates with the pump 19) . The water is discharged to the outlet pipe 7 (that is, the other end of the pipe 6a communicates with the sample water outlet pipe 7) . At this time, the sample water from the sample water introduction pipe 5 flows through the valve port A → the valve port H → the pipe 6b → the valve port D → the valve port E → the drain pipe 8 (that is, the pipe 6b is the sample water introduction pipe). 5) and the pipe 6b is filled.
[0018]
Next, when the rotor is rotated to return to the state of the solid line in FIGS. 1 and 2 (converted to the first switching state) , the carrier is press-fitted from the pump 19 into the valve port G → the valve port H → the pipe 6b. (That is, one end of the pipe 6b communicates with the pump 19) , and the sample water filled in the pipe 6b flows through the valve port D → the valve port C and is discharged to the sample water outlet pipe 7 (that is, the other end of the pipe 6b). Is communicated with the sample water outlet pipe 7) . At this time, the sample water from the sample water introduction pipe 5 flows through the valve port A → the valve port B → the pipe 6a → the valve port F → the valve port E → the drain pipe 8 (that is, the pipe 6a is the sample water introduction pipe 5). The pipe 6a is filled up.
[0019]
Since the sample water is alternately introduced into the pipes 6a and 6b in this way, timing control is performed to switch the rotor when all the sample water in the pipe 6a or 6b is pushed out to the sample water outlet pipe 7. Thus, the carrier is discharged only into the drain pipe 8 and is not discharged into the sample water outlet pipe 7.
[0020]
That is, the sample water sample water outlet pipe 7, as shown in FIG. 3 (a), by defining the amount of cut is such that continuous. FIG. 3B is a diagram showing a state in the pipe in the conventional case (for example, there is no pipe 6b and the valve ports D and H are closed), and the sample water and the carrier are alternately filled. become. Therefore, in this embodiment, since the concentration of iron in the sample water can be continuously analyzed and measured, it is easy to construct a system for processing (for example, alarm generation) based on the continuous change in the concentration. It becomes.
[0021]
In addition, although it is desirable to collect sample water only completely so that a carrier is not included, it is also possible to collect the sample water almost continuously so that some carriers are included. Even in this case, there is an advantage that the sampling interval of the sample water is shortened as compared with the conventional case where the amount of the sample water and the amount of the carrier are “the amount of the sample water ≦ the amount of the carrier”.
[0022]
【The invention's effect】
As described above, according to the present invention , since sample water can be collected continuously, the carrier contained in the sample water collected by a predetermined amount can be reduced to zero, and the analysis of the iron concentration in the sample water can be continuously performed. Will be able to do.
[Brief description of the drawings]
FIG. 1 is a block diagram of an iron content analysis apparatus according to an embodiment of the present invention.
FIG. 2 is an enlarged view of a portion of the sample water cutting device according to the embodiment.
FIG. 3A is an explanatory diagram of a state in a pipe of sample water obtained by the present embodiment,
(B) is explanatory drawing of the state in piping of the sample water obtained by the conventional method.

Claims (2)

Sample water intake means for collecting the system water of the plant to obtain sample water, and dissolution means for injecting a dissolving agent into the sample water sent from the sample water intake means to dissolve iron in the sample water, An iron analyzer comprising: a reaction means for injecting a reaction solution into sample water sent from the dissolving means to react with iron; and an iron content detecting means for detecting the iron concentration in the sample water sent from the reaction means. ,
The sample water intake means includes a sample water cutting device for connecting the first pipe and the second pipe,
The sample water cutting device is:
A sample water introduction pipe for introducing the sample water, a sample water outlet pipe for discharging the sample water from the sample water cutting device, and a carrier supply pump capable of supplying the carrier from the storage tank of the carrier; Set the inner diameter and length of the second pipe equal,
A first switching state in which the first pipe communicates with the sample water introduction pipe, and one end of the second pipe communicates with the carrier supply pump, and the other end of the second pipe communicates with the sample water outlet pipe; and the sample water introduction pipe To the second switching state in which one end of the first pipe communicates with the carrier supply pump, and the other end of the first pipe communicates with the sample water outlet pipe.
In the first switching state, the sample water is introduced into the first pipe, the carrier is supplied to the second pipe, and the sample water introduced in the second switching state is discharged.
In the second switching state, the sample water is introduced into the second pipe, and the carrier is supplied to the first pipe to discharge the sample water introduced in the first switching state.
An iron analyzer, wherein the state of the sample water cutting device is changed while the carrier is filled in the first pipe or the second pipe.   2. The iron analyzer according to claim 1, wherein the sample water flowing through the sample water introduction pipe has a Reynolds number set to a flow velocity at which a turbulent flow region is obtained.

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