JPS6121164B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ozone generator that detects defective discharge of condensed water in an air cooler for raw air to warn of a decrease in ozone production due to deterioration of the dew point of raw air. .

Conventionally, there has been a device of this type as shown in FIG. In the figure, 1 is a blower for supplying raw air, 2 is an air cooling section consisting of a primary cooler 3, a secondary cooler 4, and a refrigerator 5, 6 is an air drying section with a built-in heater for regenerating adsorbent, 7 is an ozone generator, 8 is a power source for applying high voltage to the ozone generator 7, 9 is a dew point meter for measuring the dew point of raw air, 10 is an ozone generator, a blower, and cooling water for the air cooling section. This is a cooling water pump that supplies

Moreover, FIG. 2 shows the structure and drain discharge circuit of the secondary cooler 4 of the air cooling section 2, and 4a
4b is a drain trap that always drains a certain amount of moisture in the air condensed in the secondary cooler 4 to the outside of the system, 4b is a pressure equalization pipe that equalizes the pressure in the drain trap 4a with the pressure in the secondary cooler, and 4c is a pressure equalization pipe. A strainer removes dust from the drain, 4d is a bypass pipe that drains water from the secondary cooler during drain trap maintenance, and 4e is a drain separator that separates moisture from the air condensed in the secondary cooler. be.

Next, the operation will be explained. Raw air is taken in from outside air by a blower 1 such as a Roots type blower, compressed and pressurized, and sent to an air cooling section 2 . In this air cooling section 2, the primary cooler 3 cools the water, and the secondary cooler 4 cools the refrigerant gas or cold water produced by the refrigerator 5.
Produces cold air around ℃. Further, in the secondary cooler 4, moisture in the air condensed inside the cooler is separated by a drain separator 4e and discharged from a drain trap 4a.

The cold air is guided to the air drying section 6, and is supplied to the ozone generator 7 as highly dry air with an atmospheric pressure dew point of about -50° C. by means of a solid adsorbent. In the ozone generator 7, a silent discharge is generated between a high voltage electrode tube (glass electrode) and a ground electrode (metal electrode), and ozone is generated from oxygen in the air in this discharge gap. The high voltage necessary for silent discharge is supplied by a power source 8 comprising a control device such as a voltage regulator or a high frequency inverter, and a high voltage step-up transformer. Cooling water for suppressing heat generation due to discharge in the ozone generator 7, cooling water for the primary cooler 3 of the air cooling unit 2, cooling water for the refrigerator 5, and cooling water for the blower 1 are supplied by a cooling water pump 10. Ru.

It is known that there is a close relationship between the dryness of the air supplied to the ozone generator 7 and the ozone generation efficiency. Figure 3 shows the relationship between the raw air dew point and ozone production efficiency. Generally, the atmospheric pressure dew point of the raw air supplied to the ozone generator 7 is about -50°C, and when the dew point decreases from -50°C to -30°C, the ozone generation efficiency decreases by about 15%. Furthermore, when the dew point deteriorates, the production of nitrogen oxides becomes noticeable, which causes nitric acid to be produced inside the ozone generator. This nitric acid reacts with other substances, causing dirt to adhere to the electrodes, which reduces the ozone generation efficiency and at the same time has an adverse effect such as corrosion on the materials that make up the equipment, impeding the operation of the ozone generator.

Conventionally, there has been a device equipped with a dew point meter 9 between the air drying section 6 and the ozone generator 7 in order to prevent problems caused by a decrease in the dew point of the raw air.

Dew point meters that measure dew points above -50°C are known to detect changes in capacitance, but they are generally configured so that the dew point temperature, the meter's indication, and the output are linear. It was expensive. Additionally, the sensor deteriorated and required calibration approximately once every six months to a year. For this reason, there are few ozone generators that are actually equipped with a dew point meter, and the reality is that the dew point control of raw air is hardly implemented.

Conventional ozone generators are configured as described above, but those equipped with a dew point meter are not suitable for reasons such as unnecessarily expensive dew point measurement, troublesome maintenance, and the need for advanced maintenance techniques. In practice, it was rarely used and had the disadvantage that the dew point of the raw air was not controlled.

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional ones, and among the various causes of deterioration of the dew point of raw air, air due to poor drain discharge in the secondary cooler of the air cooling section. Focusing on the deterioration of the dew point of raw air as the moisture adsorption load increases in the drying section, we developed a dew point alarm that detects drain discharge failure in the secondary cooler of the air cooling section and has an alarm function. By using this dew point alarm signal as an interlock for the operation of the ozone generator, it is possible to prevent operation when the dew point has deteriorated, and it has a simple and inexpensive dew point alarm function that does not require a dew point meter. The present invention provides an ozone generator that provides an ozone generator.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 4 shows the drain discharge circuit of the secondary cooler of the air cooling section. 4 is the secondary cooler body,
4a is a drain trap installed in the drain discharge circuit; 4b is a pressure equalizing pipe for equalizing the pressure in the drain trap 4a with the pressure in the secondary cooler 4 to prevent aerodynamics of the drain trap; 4c is a drain Strainer to remove dust inside, 4d is bypass piping to drain water from the secondary cooler during drain trap maintenance, 4e
4F is a drain separator installed in the secondary cooler, and 4F detects the liquid level of drain that has accumulated in the drain piping or secondary cooler due to a drain discharge failure such as a drain trap, and issues an alarm signal at the set liquid level. This is a liquid level switch that has the function of supplying liquid to the outside.

Next, the operation will be explained. The flow of raw material air throughout the ozone generator is the same as that of the conventional device, so it will be omitted, and the operation of the drain discharge circuit of the secondary cooler in the air cooling section will be explained here.

The raw air cooled to about 40° C. by the primary cooler 3 of the air cooling section is led to the secondary cooler 4. In the secondary cooler 4, the raw air is cooled to about 5° C. by refrigerant gas or low-temperature cold water supplied from the refrigerator 5, and then sent to the air drying section. On the other hand, moisture in the feed air condensed in the secondary cooler 4 is separated by a drain separator 4f and discharged to the outside of the system through a drain trap 4a. The drain trap 4a has a ball-shaped float inside the trap, and when drain from the cooler stays inside the trap, the float is pushed up by the buoyancy, and the drain outlet is opened to discharge the drain to the outside of the system. It has a structure that allows Further, a strainer 4c is installed in front of the drain trap 4a to remove foreign matter such as dust in the drain.

In this invention, when foreign matter such as dust gets clogged in the strainer, drain trap, or drain piping and blocks the drain circuit, moisture in the raw air that condenses in the cooler stays in the cooler.
Moreover, as the amount of water in the cooler continues to increase, the cold air containing a large amount of moisture is sent to the air drying section, and as the moisture adsorption load in the air drying section increases, the dew point of the raw air deteriorates. Drain trap 4
There is a liquid level switch 4 in the pressure equalizing pipe connecting a and the cooler.
f and supplies an alarm signal to the outside when the drain in the circuit reaches the liquid level set by the liquid level switch, thereby interlocking the operation of the ozone generator and protecting the equipment, especially the ozone generator. It is an attempt to measure the

The liquid level switch 4f is a type that combines a float with a built-in magnet and a reed switch, and has a configuration that allows the alarm liquid level to be set arbitrarily by changing the position of the reed switch as appropriate. By determining the relationship between the water level and the dry air dew point at that time, it is possible to determine the critical liquid level that can ensure the specified dew point (-50°C or less), and by using this as the alarm setting value, highly accurate dew point management is possible. It is possible.

In this way, this invention can prevent the equipment from operating in a state where the dew point has deteriorated by detecting the phenomenon that directly causes the deterioration of the dew point of the feed air.Moreover, the liquid level switch has a very simple structure. It has the advantage that it can always be used in a stable state, and that the alarm mechanism itself has a simple configuration because it does not indicate the dew point, so there is no need for maintenance.

In addition, it is possible to determine the cycle of drain traps and foreign matter clogging in the strainer, which are the direct cause of a rise in the liquid level in the secondary cooler, and to perform maintenance such as periodic disassembly and cleaning based on this cycle. It also has the advantage of being able to prevent the drain liquid level from rising inside the vessel, allowing operation to continue in a stable state at all times.

In the above embodiment, the liquid level switch 4f is installed in the pressure equalizing pipe 4b connecting the secondary cooler 4 and the drain trap 4a, but as shown in FIG. The same effect as in the above embodiment can be obtained even if the pipe is installed in the drain discharge piping between the pipe and the pipe. In addition, although the liquid level switch used was a combination of a float and a reed switch, it is also possible to use a floatless type liquid level switch that uses an electrode rod or a liquid level switch that detects changes in capacitance due to changes in liquid level. A similar effect can be obtained by using .

As described above, according to the present invention, the deterioration of the dew point of the feed air is configured to detect an increase in the drain liquid level in the cooler due to a drain discharge failure in the secondary cooler of the air cooling unit. So,
It has become possible to equip ozone generators with raw air dew point alarms that are inexpensive and do not require maintenance. Therefore, it is possible to prevent accidents in the ozone generator due to the insufficient amount of ozone production and the production of nitric acid, which is highly effective.

[Brief explanation of the drawing]

Figure 1 is a flow diagram showing the configuration of a conventional ozone generator, Figure 2 is a diagram showing the drain discharge circuit of the secondary cooler of the air cooling system, and Figure 3 is a diagram showing the relationship between the dew point temperature of raw air and ozone generation efficiency. 4 is a diagram showing the drain discharge circuit of the air cooling section secondary cooler according to one embodiment of the present invention, and FIG. 5 is a diagram showing the drain discharge circuit of the air cooling section secondary cooling device according to another embodiment of the present invention. It is a drain discharge circuit diagram of a container. In the figure, 1 is a blower for supplying raw air, 2 is an air cooling section, 6 is an air drying section, 7 is an ozone generator, 8 is a power source, 9 is a dew point meter, and 10 is a cooling water pump. In the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Scope of Claims] 1. In an ozone generator comprising a raw material air cooler, a drying device for the cooled air, and an ozone generator that generates ozone from the dry air by silent discharge; An ozone generator comprising: a liquid level switch that detects a rise in the level of water that condenses and stagnates due to air cooling; and a dew point alarm that generates an alarm signal based on the detected value.