JPH02110298A - Cooling tower - Google Patents

Abstract

PURPOSE:To kill or suppress the proliferation of bacteria or microbe in water to be cooled by dispersing ion exchanging bodies combined to metallic ion onto the surface of filler. CONSTITUTION:A filler 4 is constituted of a multitude of pipes to permit the flow down of water (a) to be cooled from a spraying unit 3 while being divided into fine streams as well as the passing of ascending air stream, generated by a fan 2, while being divided into fine streams. According to this method, the water (a) to be cooled and inflow air are contacted efficiently to cool the water (a) to be cooled by depriving the latent heat of the water itself, which is caused by the evaporation of the water. The filler 4 is produced from a synthetic resin mixed with synthetic zeolite or ion exchanging bodies effected as anti-fungus agent when it is added with silver ion and zinc ion, for example. According to this method, bacteria or microbe in the water (a) to be cooled, which is sprayed from a spray pipe 3a and made to flow down along the surface of the filler 4, may be killed or suppressed in the proliferation thereof.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a cooling tower that is used when cooling water for various industrial purposes and air conditioning is repeatedly applied, and which is connected to a heat exchanger of equipment to be cooled. The present invention relates to a cooling tower that is installed to circulate cooling water in the heat exchanger, and cools the high-temperature cooling water from the heat exchanger by bringing it into contact with surrounding air.

Specifically, the method includes a filling material for increasing the contact of the water to be cooled with air, a water sprinkling section for sprinkling the water to be cooled onto the filling material, and a recovery section for collecting the water to be cooled from the filling material. Regarding a certain cooling tower.

[Conventional technology]

Conventionally, in this type of cooling tower, a plate-shaped or multi-tubular packing made of resin or the like is provided inside the cooling tower, and the object to be cooled is sprinkled onto the filling from a water spraying section, and the filling is used to cool the object with air. The structure was designed to increase the cooling efficiency of the water to be cooled by increasing the contact area and time of the water to be cooled and improving the thermal and flow characteristics.

By the way, in such a cooling tower, since the water to be cooled is cooled by contact with the atmosphere, oxygen dissolves into the water to be cooled. As a result, bacteria and microorganisms first occur in the filling, and then these bacteria and microorganisms adhere and propagate on the inner surface of the cooling water circulation system, and inorganic suspended substances adhere to the sticky substances they produce. Furthermore, as microorganisms repeatedly adhere to the upper layer, slime is formed throughout the system. Formation of such slime induces poor circulation such as clogging of the filler, piping, and heat exchanger, leading to a decrease in cooling performance, and is also unhygienic, which is undesirable.

For this reason, conventionally, as a slime countermeasure, cooling water is
Measures such as mixing organic nitrogen sulfur-based drugs or amine-based drugs as bacteria and microorganism growth inhibitors, or mixing quaternary ammonium chlorine-based drugs or bromine-based drugs as microbial adhesion prevention agents, or cooling water. stop the entire circulatory system,
Sterilization methods used include adding sodium hypochlorite and hydrogen peroxide.

[Problem to be solved by the invention]

However, according to the above-mentioned conventional technology, the generation and proliferation of bacteria and microorganisms in the circulation system including the cooling tower is considered to be inevitable;
Because it relied solely on sterilization and adhesion prevention through the injection of chemicals, it had the following drawbacks.

In other words, in order to constantly replenish the system with an amount of water equivalent to the amount of volatilization water and the amount of blowing water to prevent salt concentration, it is not enough to just add microbial growth inhibitors and anti-adhesion agents once. It is necessary to continuously inject the chemical in an amount corresponding to the amount of water supplied each time, which reduces the cost of the chemical,
Maintenance costs were high.

Furthermore, after the disinfectant is added, it is necessary to remove the detachment slum and discharge the disinfectant solution, and during this time there is an inconvenience that equipment related to the cooling water circulation system cannot be moved.

An object of the present invention is to eliminate the above-mentioned conventional drawbacks.

[Means to solve the problem]

In order to achieve this object, the cooling tower according to the present invention is characterized in that an ion exchanger to which metal ions are bonded is dispersed on the surface of the packing.

The packing is characterized in that it is made of a resin mixed with the ion exchanger.

Furthermore, the ion exchanger is dispersed on surfaces of the water spraying section and the recovery section that come into contact with the water to be cooled.

[For production]

In other words, it is well known that ion exchangers to which metal ions such as silver, copper, tin, and zinc are bound have an antibacterial effect that kills bacteria or suppresses their growth when they come into contact with bacteria. Since ion exchanger fine particles having an antibacterial effect are dispersed on the surface of the filling material, although oxygen is dissolved in the water to be cooled, bacteria and microorganisms in the water to be cooled that come into contact with the filling material are killed or removed. Proliferation is suppressed.

Even if microorganisms attach and slime is formed, the slime is formed on the microorganisms that have been selected to adhere to areas where there are no ion exchanger particles that have antibacterial effects, and the amount is small. It easily washes away with water flow.

Moreover, the metal ions that bind to the ion exchanger are stable without being exchanged unless they have a higher selectivity for the ion exchanger than for these metal ions. When using ordinary water or industrial water as cooling water, which contains almost no highly selective metal ions, the antibacterial metal ions will not be dissolved into the liquid, and the antibacterial effect will also be reduced. Lasts semi-permanently.

In addition, when the ion exchanger is dispersed on the surface of the filler by mixing the ion exchanger into the resin itself, which is the constituent raw material, and molding the filler, it is possible to disperse the ion exchanger on the surface. Not only is there no decrease in the productivity of the packing, but the ion exchanger is strongly bonded to the packing and has excellent durability.

Furthermore, when the ion exchanger is dispersed on the surface of the water sprinkling section and the recovery section that comes into contact with the water to be cooled, the antibacterial effect is further enhanced.

〔Effect of the invention〕

Therefore, in a cooling tower made of a packing material in which the above-mentioned ion exchanger is dispersed, the generation and proliferation of bacteria and microorganisms in the packing material, which is the starting point for slime formation, can be semi-permanently prevented or suppressed. It goes without saying that slime is extremely unlikely to be formed in the filling, but also in cases where slime is formed in parts of the cooling water circulation system other than the filling, i.e., in the heat exchanger or piping of the equipment to be cooled. Even so, the rate of slime formation is extremely slow.

This makes it possible to drastically reduce the amount of growth inhibitors and anti-adhesion agents used in the cooling water circulation system.
It is possible to significantly reduce the cost of chemicals and maintenance costs, and furthermore, the number of injections of the disinfectant is reduced, and the number of times the equipment is stopped due to this is also significantly reduced, increasing the operating rate of the equipment. Therefore, it is now possible to save on maintenance costs.

〔Example〕

The present invention will be explained in detail below.

As shown in the figure, the cooling tower (A) is connected to heat exchangers (B) of various equipment to be cooled via a circulation path (La) and a circulation path (Lb) equipped with a pump (P). , which cools the high temperature water to be cooled (a) from the heat exchanger (B).

Specifically, within a cylindrical outer wall (1) with an open upper end, a blower (2) is provided at the open upper end (1a), and a water sprinkling part (3) and a filling are provided below. (4), a collection section (5) is disposed at the bottom, and an eliminator (6) is disposed between the blower (2) and the water sprinkling section (3). .

The blower (2) blows air into the outer wall (1) from a louver (7) provided at a location between the filling material (4) and the recovery section (5) in the outer wall (1). It is made to flow in, pass through the filling (4), and be exhausted to the open upper end (1a).

The water sprinkling section (3) uniformly sprays the water to be cooled (a) from the heat exchanger (B) onto the filling (4), and includes a rotary water sprinkling pipe (3a). and a motor (3b) that drives it.

The filling (4) has a multi-tubular shape, and flows down the water to be cooled (a) from the water sprinkling section (3) in a trickle, while at the same time reducing the rising air generated by the blower (2). By passing the water in a trickle, the water to be cooled (a) is efficiently brought into contact with the inflowing air, and the water to be cooled (a) is cooled by absorbing the latent heat accompanying the evaporation of the water itself.

The filling (4) is made of a synthetic resin mixed with synthetic zeolite as an ion exchanger to which silver and zinc ions are added and which acts as an antibacterial agent. In other words, the surface of the filler (4) has antibacterial properties due to the dispersion of the antibacterial agent. Therefore, the sprinkler pipe (3
Bacteria and microorganisms in the water to be cooled (a) that is dispersed from a) and flows down along the surface of the filling material (4) come into contact with the antibacterial surface of the filling material (4) as they flow down. As a result, they die or their reproduction is suppressed.

The recovery section (5) is a tank that recovers the dripping cooling target water (a) from the filling material (4) and sends it to the heat exchanger (B).

The eliminator (6) removes and collects water droplets from the exhaust gas.

The eliminator (6) and the above-mentioned collection section (5) and the water sprinkling pipe (3a) of the water sprinkling section (3) are also made of the same antibacterial agent-containing synthetic resin as mentioned above.
The surface that comes into contact with the water to be cooled (a) has antibacterial properties.

[Experiment example]

Examples of experiments conducted by the present inventor to prove that ion exchangers bound with metal ions have antibacterial properties are shown below.

Experimental Example 1 [1] Preparation of sample Synthetic zeolite was used as an ion exchanger, and silver ions and zinc ions were added to it at a ratio of 2.5 to 3.
After adding 3%, it is dried and ground to a particle size of 1 μm to 2 μm. 2% of each of the pulverized products was added to polypropylene resin.
, 6%, 0% dispersed three types of resin plates (A), (B)
.

Create (C). Each resin plate (A), (B), (C
) is 1 cm×1 cm×3 mm.

[Preparation of 2 test solutions Pseudomonas
After collecting the bacteria and culturing them in a standard TGE medium at a temperature of 25°C for 2 days, the culture solution 2 of the Pseudomonas bacteria was
Create a 1β test solution by adding pure water to 0cc.

[3] Mischief The three types of resin plates (A) and (B) are added to the test solution.

After adding (C) and leaving it at room temperature for 6 days, the resin plate (
A), (B), and (C) were taken out and air-dried, and then the surface of the resin plate was observed using a scanning electron microscope.

[4] As shown in Results Table 1, samples containing no synthetic zeolite (
In C), the entire surface was covered with bacteria, but in the sample mixed with synthetic zeolite (^), in (B), the resin surface was observed to be partially covered but most of it was observed to have an antibacterial effect. It was confirmed that it has.

Experimental Example 2> [1] Preparation of Samples Three types of FRP resin plates (A') were prepared by dispersing 2%, 5%, and 0% of the same synthetic zeolite as that prepared in Experiment 1 in the resin, respectively. , (B') and (C') are created. FRP resin plate (A'), (B'), (C'
) is 5 cm x 5 cm x 5 +
++m.

[2] Sample preparation A bacterial solution with a bacterial content of 105 cells/ml is prepared.

[3] Drop 1 ml of the bacterial solution onto each of the rubbed FRP resin plates (A'), (B'), and (C''), and after culturing at a temperature of 37°C for 18 hours, wash the bacterial solution with physiological saline. Then, the number of bacteria in the cleaning solution was measured using a bacteria test paper. Two types of bacteria test paper were used: one for general bacteria and one for Escherichia coli.

[4] Results As shown in Table 2, the bacterial reproduction rate in the sample mixed with the ion exchanger was 1% compared to the sample without the mixture.
/100 to less than 1/1000, clearly demonstrating that it has an antibacterial effect.

As is clear from the above experiment/AJ, by imparting antibacterial properties to the surface that comes into contact with the water to be cooled (a),
In order to perform antibacterial treatment against the air in the water to be cooled (a), as in the above embodiment, the surface of not only the filler (4) but also the sprinkler pipe (3), the recovery part (5), and the eliminator (6) When antibacterial properties are imparted, the effect of preventing and suppressing the growth of bacteria is higher than when only the filling (4) is imparted with antibacterial properties.

[Another example]

Another embodiment of the present invention will be shown below.

(1) In the above examples, synthetic zeolite was shown as the ion exchanger, but other examples of the ion exchanger include natural zeolite and ion exchange resins.

2> In the above examples, the metal ions include silver ions,
Although zinc ions are shown, the metal ions may also be copper ions or tin ions.

<3> In the above embodiment, an ion exchanger to which silver ions are added and an ion exchanger to which zinc ions are added are used in combination, but they may be used alone.

<4> In the above embodiment, as a dispersion means for dispersing the ion exchanger on the surface of the filler (4), a means of making the filler (4) from a resin mixed with an ion exchanger was adopted. Examples of the method include applying a resin or paint mixed with an ion exchanger to the surface of the filler (4), or pasting a resin sheet containing an ion exchanger on the surface of the filler (4). It may also be a means to do so.

5> In the above embodiment, a forced draft type cooling tower (A) was shown, but the present invention can also be applied to a natural draft type cooling tower (A).

6> In the above embodiment, the filling (4), the water sprinkling part (3),
Ion exchangers are dispersed on the surfaces of the recovery section (5) and eliminator (6), but in addition to these, ion exchangers are also dispersed on the inner walls of the circulation path, the inner walls of the cooling tower, and other places that come into contact with the water to be cooled. You can let me.

[Brief explanation of drawings]

The drawing is a schematic sectional view showing an embodiment of a cooling tower according to the present invention. (A)...Cooling tower, (1)...Outer wall,
(2)...Blower, (3)...Water spray section, (4)...Filling material, (5)...Collection section, (6) ...Eliminator.

Claims (1)

[Claims] 1. A filling for increasing the contact of the water to be cooled with air, a water sprinkling section for sprinkling the water to be cooled onto the filling, and collecting the water to be cooled from the filling. 1. A cooling tower having a recovery section, the cooling tower having an ion exchanger to which metal ions are bonded dispersed on the surface of the packing. 2. The cooling tower according to claim 1, wherein the packing is made of a resin mixed with the ion exchanger. 3. The cooling tower according to claim 1 or 2, wherein the ion exchanger is dispersed on a surface of the water sprinkling section and the recovery section that comes into contact with the water to be cooled.