JPH052730U - High concentration ammonia automatic dissolver - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain high-concentration aqueous ammonia and detect and alarm abnormally high concentrations. By controlling the supply amounts of ammonia and pure water for dilution to an ammonia dissolution tank 18 via control valves 14 and 16 operated by a concentration measuring device 40 and a level switch 20, ammonia water of a predetermined concentration can be obtained. In the automatically manufactured device, the concentration measuring device 40 is constituted by an ultrasonic densitometer or a specific gravity densitometer. In this case, each of the densitometers has a one-way inclination characteristic up to a concentration range in which the proportional relationship between the detected value (ultrasonic wave propagation velocity or specific gravity) and the concentration reaches a high concentration range. In addition, it is possible to reliably detect and warn abnormally high concentrations.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

  The present invention is applied in order to maintain a constant pH value in water quality adjustment of boiler plants, etc. Depending on the dissolution device of the ammonia to be put in, especially when the specified high-concentration ammonia water is automatically The present invention relates to an automatic dissolution apparatus configured to be provided to

[0002]

[Prior art]

  When adjusting the water quality, in order to regulate the ammonia injection amount Although water is required, this constant concentration of ammonia water has generally been high in the past. By measuring and mixing a predetermined amount of commercially available ammonia water and pure water for dilution, It was done by However, this method requires that ammonia has a strong pungent odor. Therefore, the workability was poor and there was a strong demand for improvement.

[0003]   Therefore, the applicant has previously developed and applied an automatic dissolution apparatus for ammonia (for example, For example, Japanese Utility Model Publication No. 57-13306) has already been put to practical use. Below this device I will briefly explain about it. As shown in FIG. Closed melting with monia supply system 12 connected via control valves 14 and 16 respectively It consists of a tank 18, which has a level switch 20 and an It is driven by an electric conductivity measuring device 22 for detecting the ammonia concentration and a motor 24a. A stirrer 24 is provided, and each is connected to a controller 26. like this In the configuration, the ammonia water in the tank 18 is supplied to the water quality adjusting system by the supply pump 28. 30 and the ammonia water level in the tank 18 drops to a predetermined minimum set water level. Then, the control valve 14 is opened / closed via the level switch 20 so that the pure water is stored in the tank 18. Flows in. Next, the water level in the tank 18 rises to a predetermined maximum set water level. Then, the control valve 14 is closed, the inflow of pure water is stopped, and the control valve 16 is opened. As a result, ammonia flows into the tank 18. At this time, the stirring device 24 is also operated. Be done. Ammonia in pure water detected by the conductivity measuring device 22 The control valve 16 is closed when the concentration of the predetermined concentration reaches a predetermined target concentration. Ammonia water is achieved automatically.

[0004]

[Problems to be solved by the device]

  As described above, according to the device (hereinafter, referred to as a conventional device), the concentration of the predetermined concentration You can get monia water automatically. However, in the above device, There was a basic difficulty as described in.

[0005]   That is, the device is such that ammonia water has a constant relationship between its concentration and conductivity. Although the development was achieved by finding out that Had very limiting properties. That is, in FIG. 4 showing the above characteristics, The concentration-conductivity curve has the same peak value in the region near the concentration of 5%. When the peak value was exceeded, the slope gradient was extremely small. Because of this, before In this device, the concentration of ammonia water is limited to 5% or less, preferably 3% or less And it is impossible to detect an abnormally high ammonia concentration. It was In the former case, this means The size of the supply pipe system was increased, and in the latter case, the reliability of the device was impaired.

[0006]   Therefore, the purpose of the present invention is to obtain a predetermined high-concentration aqueous ammonia. A high-concentration ammonia automatic dissolution device that can alert abnormally high concentration Especially.

[0007]

[Means for Solving the Problems]

  In order to achieve the above object, the high-concentration ammonia automatic dissolution apparatus according to the present invention is A sealed melting system in which a pure water supply system and an ammonia supply system are connected to each other via control valves. The dissolution tank is a level that detects the highest and lowest water levels in the tank. Switch and an ultrasonic densitometer to detect the ammonia concentration in the tank or specific gravity A concentration measuring device consisting of a thermometer and a stirring device for stirring the ammonia water in the tank And control each of the control valves, level switch, concentration measuring device, and stirring device. The control valve of the pure water supply system can be connected to the Controls the ammonia supply system by opening at the set water level and closing at the maximum set water level The valve is opened at the above-mentioned maximum set water level, and a predetermined ammonia detected by the concentration measuring device is detected. It is closed at near concentration, and the agitator is operated by opening the ammonia supply system control valve. It is characterized in that it is configured as follows.

[0008]   In this case, the controller is equipped with an alarm setting device and a logic circuit, and the alarm setting device measures the concentration. When the ammonia concentration signal output from the device reaches the specified concentration, the target concentration signal is reset. The alarm signal is output to the alarm device when an abnormally high concentration is reached, The logic circuit calculates the target concentration signal and outputs an ammonia injection stop signal as an ammonia signal. A) It can be configured to output to the supply system control valve.

[0009]   The concentration measuring device is provided with a temperature compensating mechanism, and the compensating mechanism is an ultrasonic densitometer. Is composed of a temperature-concentration compensation function setter in the It is composed by enclosing a liquid with the same expansion coefficient as ammonia water. It is suitable.

[0010]   In addition, if the ammonia supply system consists of ammonia gas or liquefied ammonia, In this case, the controller predicts the ammonia concentration until the ammonia concentration reaches the target concentration. Calculate the supply time and output the ammonia injection stop signal once before the estimated supply time. Then, the difference between the actual concentration of ammonia and the target concentration is detected, and then the concentration difference is compared. In response, the ammonia injection signal is output again for a predetermined time, and the It is preferable to configure the density so as to sequentially match the target density (step operation). .

[0011]

[Action]

  The automatic dissolution apparatus of the present invention is basically constructed in the same manner as the above-mentioned conventional technology. However, the ammonia concentration measuring device uses an ultrasonic densitometer or a specific gravity concentration. It consists of a total. However, this densitometer, even in ultrasonic densitometer, Also in the profilometer, the detected value (ultrasonic wave propagation velocity or specific gravity), as described later The proportional relationship between the concentration and the concentration has almost the same steep slope up to the high concentration range. It has directional tilt characteristics.

[0012]   Therefore, according to the present invention, it is possible to easily obtain a predetermined high-concentration ammonia water. It is possible to warn of abnormally high concentration and, therefore, automatic dissolution of ammonia The size of the equipment and water quality control system equipment can be reduced and the reliability of the entire equipment can be secured. You can Further, according to the present invention, the temperature change mechanism is provided by providing the temperature compensation mechanism. The density detection error due to movement can be easily avoided, and by step operation Concentration detection by generated bubbles when using ammonia gas or liquefied ammonia The output error can be reliably prevented.

[0013]

【Example】

  Next, an embodiment of the high-concentration ammonia automatic dissolution apparatus according to the present invention will be described with reference to the accompanying drawings. Will be described in detail below with reference to. For convenience of explanation, the conventional device shown in FIG. The same reference numerals are given to the same components as those of the storage unit, and detailed description will be omitted.

[0014]   First of all, the high-concentration ammonia automatic dissolution apparatus of the present invention uses the concentrated ammonia used for this. Except for the degree measuring device, as described above, the overall configuration is basically the same as that of the conventional art. Is the same as That is, although overlapping, a brief description will be given again. In FIG. The dynamic dissolution apparatus includes a pure water supply system 10 and an ammonia supply system 12, which have control valves 14 and 14, respectively. It consists of a closed dissolution tank 18 connected in communication via 16 and The claw 18 is provided with a level switch 20, a concentration measuring device 40 and a stirring device 24. Connected to the controller 50.

[0015]   However, in the automatic dissolution apparatus of the present invention, the concentration measuring device 40 is It consists of a densitometer or a specific gravity densitometer. Therefore, first, we will explain the ultrasonic densitometer. Then, the densitometer measures the ultrasonic wave propagation velocity (detection value) -concentration as shown in FIG. It has a proportional relationship characteristic. Next, we will explain the specific gravity densitometer. It has a proportional relationship of specific gravity (detection value) -concentration as shown in Table 1.

[0016]

[Table 1]

[0017] That is, the concentration measuring device 40 used in the present invention has a specific gravity even in an ultrasonic densitometer. Even in the densitometer, the proportional relationship between the detected value and the concentration reaches the high concentration range. It will be understood that it has a unidirectional slope characteristic with nearly the same steepness . In addition, in FIG. 4 and Table 1, the concentration range is 10 to 30% or 1 to 30%. Although shown, the properties are approximately the same over the entire concentration range. In addition, concentration measurement In the device 40, the detection value from the detection sensor 42 (ultrasonic wave propagation velocity or ratio Weight) is calculated in the instrument body 44 and output as a concentration signal. The signal is introduced into the alarm setting device 52 of the controller 50, and the alarm setting device 52 detects the concentration signal. When the predetermined concentration is reached, the target concentration signal is output to the logic circuit 56 and an abnormal high When the concentration is reached, an alarm signal is output to the alarm 54, and the logic circuit 56 The target concentration signal is calculated and the ammonia injection stop signal is sent to the ammonia supply system control valve 16 It is configured to output to.

[0018]   In such a configuration, the ammonia dissolving operation is the same as that of the above-mentioned conventional technique. It That is, the ammonia water level in the tank 18 drops to a predetermined minimum set water level. Then, first, the control valve 14 of the pure water supply system 10 is opened and closed in a predetermined manner to set a predetermined amount of pure water. Flows into the tank 18, and then the control valve 16 of the ammonia supply system 10 is opened. As the ammonia begins to flow into the tank 18, the agitator 24 is activated, When the ammonia concentration detected through the concentration measuring device 40 reaches the target concentration, The control valve 16 is closed so that the predetermined concentration of ammonia water is automatically achieved. It

[0019]   However, according to the present invention, the concentration measuring device, as described above, has a high concentration range. Since it has a unidirectional inclination characteristic with almost the same steep slope up to This makes it possible to easily obtain a predetermined high-concentration ammonia water and to obtain an abnormally high concentration. Can be surely warned. Therefore, if the tank of the ammonia dissolver is And the water supply system of the water quality control device and the piping system are small and weighed down to reduce the cost. It is possible to reduce the installation space. In addition, the reliability of the entire device Can be improved.

[0020]   In the present invention, when an ultrasonic densitometer is used, the temperature-concentration compensation function On the other hand, if a density meter is used, an ammonio (A) Encapsulating a liquid that has the same expansion coefficient as water facilitates the concentration compensation mechanism. As it can be achieved, concentration detection error due to temperature fluctuation of ammonia water is easy. Can be corrected to. In addition, the ammonia concentration reaches the target concentration in the controller. Ammonia is configured by calculating the estimated supply time of ammonia until it reaches If the control valve of the near supply system is configured to operate in steps, the ammonia source Concentration based on bubbles generated when using near gas or liquefied ammonia There is an advantage that the detection error can be surely prevented.

[0021]   The present invention has been described above with reference to a preferred embodiment, but the present invention is not limited to the above embodiment. Without being fixed, many design changes are possible within the spirit.

[0022]

[Effect of device]

  As described above, the high-concentration ammonia automatic dissolution apparatus according to the present invention is sealed. The supply amount of ammonia and pure water for dilution to the Controlled by a control valve that opens and closes via a concentration measuring device and level switch To automatically produce ammonia water with a predetermined concentration by In the monia automatic dissolution apparatus, the concentration measuring device is set between the detected value and the concentration. It has a unidirectional tilt characteristic with almost the same steep slope up to the concentration range where the proportional relationship is high. Since it is composed of an ultrasonic densitometer or specific gravity densitometer, A. Water can be easily obtained and an abnormally high concentration can be reliably warned. .

[0023]   Therefore, in general, only low concentration ammonia water of 3% or less can be obtained, and Compared with the conventional dissolution equipment of this kind, which was unable to warn of abnormally high concentrations, The dissolution device and water quality adjustment device can be made small and inexpensive, and the device reliability can be improved. can do. Further, in the present invention, temperature compensation for ammonia water is performed. Mechanism and a step operation mechanism for the ammonia supply system control valve may be provided. Therefore, concentration detection based on ammonia water temperature fluctuations and bubbles generated in the tank The advantage that the error can be easily and surely prevented is exhibited.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of a high-concentration ammonia automatic dissolution apparatus according to the present invention.

FIG. 2 is a propagation velocity-concentration characteristic curve diagram of the ultrasonic densitometer.

FIG. 3 is a system diagram showing a conventional ammonia automatic dissolution apparatus.

FIG. 4 is an electric conductivity-concentration characteristic curve diagram of the electric conductivity measuring device.

[Explanation of symbols]

10 ... Pure water supply system 12 ... Ammonia supply system 1
4, 16 ... Control valve 20 ... Level switch 24 ... Stirrer 28 ... Ammonia water supply pump 3
0 ... Water quality adjusting system 40 ... Concentration measuring device 42 ... Concentration measuring device detection sensor 44 ... Concentration measuring device Meter body 5
0 ... Controller 52 ... Alarm setting device 54 ... Alarm device

Claims (4)

[Scope of utility model registration request] 1. A sealed dissolution tank in which a pure water supply system and an ammonia supply system are connected to each other through control valves, the dissolution tank being a level switch for detecting the highest and lowest water levels in the tank and a tank Equipped with a concentration measuring device consisting of an ultrasonic densitometer or a specific gravity concentration meter for detecting the ammonia concentration and a stirring device for stirring the ammonia water in the tank, and controlling the respective control valves and level switches, the concentration measuring device, and the stirring device. The control valve of the pure water supply system is opened at the minimum set water level detected by the level switch and closed at the maximum set water level, and the control valve of the ammonia supply system is opened at the maximum set water level. It is configured to be closed at a predetermined ammonia concentration detected by the concentration measuring device, and the stirring device is operated by opening the ammonia supply system control valve. A high-concentration ammonia automatic dissolution apparatus characterized by the following. 2. The controller includes an alarm setter and a logic circuit, and the alarm setter outputs a target concentration signal to the logic circuit and an abnormally high concentration when the ammonia concentration signal output from the concentration measuring device reaches a predetermined concentration. The automatic high-concentration ammonia according to claim 1, wherein an alarm signal is output to the alarm device when the temperature reaches a predetermined value, and the logic circuit calculates the target concentration signal and outputs an ammonia injection stop signal to the ammonia supply system control valve. Dissolution equipment. 3. The concentration measuring device includes a temperature compensating mechanism, and the compensating mechanism is constituted by a temperature-concentration compensating function setting device in an ultrasonic densitometer, and in a specific gravity densitometer, the same expansion as ammonia water in a float. The high-concentration ammonia automatic dissolution apparatus according to claim 1, which is configured by enclosing a liquid having a coefficient. 4. The ammonia supply system is composed of ammonia gas or liquefied ammonia, and the controller calculates an ammonia predicted supply time until the ammonia concentration reaches a target concentration, and outputs an ammonia injection stop signal before the predicted supply time. After outputting once, the difference between the actual concentration of ammonia and the target concentration is detected, and then an ammonia injection signal is output again for a predetermined time corresponding to the difference in concentration, whereby the actual concentration of ammonia is made to sequentially match the target concentration. The high-concentration ammonia automatic dissolution apparatus according to claim 1, which is configured as described above.