JPS58143833A - Method for supplying chemical agent to water recirculation system of cooling tower and chemical agent container - Google Patents

Abstract

PURPOSE:To supply a chemical agent every almost constant amount continuously over a long period of time without using a special chemical liquid pouring device, by a method wherein a gel like chemical agent is accommodated in a container having an opening provided to the upper surface thereof floated on a water surface so as to leave an upper space therein and eluted from the upper surface opening part only by scattering water from the upper part of a cooling tower. CONSTITUTION:A lid body 3 having a piercing orifice 9 provided thereto is arranged on the container main body 2 of a container 1 formed by the foaming molding of PST and a protruded flange 7 is formed to the periphery thereof. On the other hand, a scale inhibitor, a corrosion inhibitor and a slime preventing agent are added to the heated molten substance of poly-EG with an average polymerization degree of 250 to be dissolved therein. In the next step, this chemical agent is flowed into the main body 2 so as to reach a depth D and gelled by cooling to form a solid 5. Subsequently, this chemical agent accommodated container 1 is floated on a water storage part in a cooling tower and water is scattered to the main body space A from the upper part of the cooling tower through the piercing orifice 9 to supply the chemical agent to recirculated water by the elution thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for continuously supplying a constant amount of a chemical to the circulating water system of a cooling tower over a long period of time without requiring a chemical injection device such as a chemical injection pump. .

Cooling towers are widely used for industrial purposes, air conditioning, and other uses, but various problems caused by water occur in the circulating water system.

For example, scale builds up on the heat exchanger and lowers the heat exchange rate, metal materials corrode, and bacteria and algae proliferate, leading to complete blockage of pipes.

One method for preventing these problems is to inject scale inhibitors, corrosion inhibitors, bactericides, algaecides, pH adjusters, and the like.

In the conventional method, the main methods for continuously supplying such a drug to a circulating water system at a constant t' are (1) diluting or dissolving the drug to an appropriate concentration; Supplied with chemical injection bonzo.

(11) A compatible solid drug is stored in a container that can communicate with the outside, and the container is immersed in a circulating water system to dissolve the drug in the circulating water.

However, the ++ method requires not only the injection of the chemical solution, but also the control panel, electrical wiring work, chemical piping work, etc., and complicated daily management such as checking the remaining amount of the chemical solution adjustment solution.

□ The method (11) can be roughly divided into two types: one is a method of attaching the container to the circulating water piping or bypass piping of a cooling water system, and the other is
21451, a solid drug is contained in a container having water passage holes on the upper and lower surfaces or on the sides, and is floated on the water surface of the water storage part of the cooling tower, and spray water from the cooling tower enters from the upper surface, This is a method in which the drug in the container is dissolved and eluted out of the container through a water hole provided on the bottom or side surface.

Although these methods are considerably simpler in terms of handling and management than (1), they have the disadvantage that supplying a fixed amount of the drug continuously defeats the original purpose. b.

That is, since all or a portion of the drug in the container is immersed in the cooling water system, the drug is constantly being dissolved, diffused, and transferred to the cooling water system. However, the operation of the cooling tower is
It is controlled by the heat load of the equipment to be cooled, and operation stops when the load is low, and in particular, in air conditioning applications, it stops in most cases at night.

At this time, the drug is oversupplied, which is not only wasted but also reduces the effectiveness of the drug.

Furthermore, since the dissolution and diffusion of the drug is promoted using water flow, the surface area of the solid drug in the container changes from time to time, making it impossible to achieve the intended purpose of supplying a constant amount of the drug.

In addition, in recent years cooling towers have had their water storage areas covered with sound-deadening mats to prevent noise generation, and in the case of small square types, structures have been introduced in which the filling placed under the sprayed water reaches all the way to the water storage area. Therefore, in the latter case of (II), it is impossible to float the drug container in the water storage section of the tower while the internal structure of the cooling tower is left as is.

In that case, it may be possible to use the container by placing it on a sound-absorbing mat or filling material, but if you apply pressure like this,
Most of the solid drugs will be in the air, so
The dissolution rate will be different from when part or all of the solid drug is immersed in water.

This invention has been made in view of the above circumstances, and it is a gel-like solid drug that is to be supplied to the cooling tower circulating water system, and the gel-like drug is housed in a gold container with an opening on the upper surface while maintaining an upper space. If the sprayed water in the cooling tower can be received by the sprayed water,
It can be used anywhere, including as a water storage area and as a sound deadening mat.

That is, the chlorinated water sprayed from the top of the cooling tower first enters the container through the through hole provided on the top surface of the drug container, filling the space between the drug and the top surface. The drug diffuses into this water and is exchanged with water newly entering the container, returning to the cooling tower circulating water. Therefore, drug-dissolved water moves to the cooling tower circulating water by the amount of water that enters the container, and the drug is supplied into the cooling tower circulating water. During this time, the water existing in the space above the drug dissolves the drug in an almost saturated state.
Since the flow rate of water entering the container from the upper surface through-hole is constant, it is possible to continuously supply a constant amount of chemicals to the cooling tower circulating water system.

Additionally, when the cooling tower stops operating, the spray water also runs out.
Since communication between the circulating water and the medicine in the container is cut off, the supply of medicine can be stopped at the same time. Moreover, since water is kept in the space between the chemical and the upper surface, the impact caused by falling sprayed water is alleviated, and the internal chemical is not destroyed, and the chemical is filled with gel-like solids. , it dissolves gradually from the surface, and there is no change in dissolution rate due to changes in surface area.

Therefore, the rate at which the drug is supplied to the circulating water system is controlled only by the water temperature, the surface area of the drug, and the size of the through hole on the top surface, apart from the dissolution rate of the drug, so there is no need to install special drug injection equipment. It is possible to design and manufacture containers and chemicals that can continuously supply a constant amount of chemicals to the cooling tower circulating water system without complicated management.

The gel-like solid drug (hereinafter referred to as gel drug) in the VC of the present invention is obtained by dissolving the necessary effective drug in polyethylene glycol having a degree of polymerization of about 130 to 500 (so that the weight ratio of polyethylene glycol is at least 25 s). Preferably, it is cooled to form a gel.

That is, this gel-like drug exhibits a relatively strong solid state, can withstand shock during transportation and use, and is compatible with water. In addition, it has been confirmed through preliminary experiments that some of the active drugs in this gel drug diffuse within the gel and are almost never eluted faster than the gel drug dissolves. This is well suited to the purpose of supplying a constant amount of water.

Furthermore, by providing a ridge on the outer periphery of the upper surface of the container, the sprayed water can be received over the entire upper surface of the container, increasing the supply of water into the container and increasing the elution rate of the drug. Uniform dissolution is ensured even if the water sprinkling condition inside is uneven, and the dissolution rate is increased, so the diameter of the through hole on the top surface can be made smaller, thus increasing the strength of the top surface of the container. There are advantages such as being able to

Note that this projecting edge is not limited to the outer peripheral portion of the upper surface, but may be provided anywhere.

The present invention will be explained in more detail by way of Examples below.

In the figure, (1) is polystyrene foam-molded so that the volume ratio is 20 times. In (2), the container body (3) is a lid body, and a projecting edge (7) is formed around the top surface, and a recess, that is, a flat part (8) surrounded by the projecting edge, has a through hole at the center position. A hole (9) is provided on one side.

Next, polyethylene glycol 60 with an average degree of polymerization of 250
Part I was heated to 80'cK to melt it, and a total of 70 parts of a scale inhibitor, a corrosion inhibitor, and a slime inhibitor were added to this as effective agents, and the mixture was thoroughly stirred so that it was well dissolved and the contents were uniform.

The thus prepared drug was poured into the container body (2) as a liquid to a depth of (D) and allowed to cool indoors, whereupon it gelled into a solid (5) after about 60 minutes. In addition,
The partition wall (6) provided in the main body is provided for the purpose of improving the fixation of the gel drug and alleviating distortion during cooling, sluggishness during transportation, and impact during use.

After the drug was gelatinized, the container body (2) and the lid (3) were sealed at their joint surfaces (4) with an adhesive.

The hole (T) is a hole through which a string is passed, and the string is used to secure the medicine container and to pull it together after use.

The cooling tower was operated by floating the drug container thus manufactured in the water storage section within the cooling tower. The cooling tower was operated for an average of eight continuous hours per day and shut down the rest of the day. In addition, the operation was irregular, with no movement on Saturdays, Sundays, and public holidays.

The results of investigating the dissolution rate of active ingredients of gel-like drugs under these conditions were as follows.

That is, the dissolution rate was determined by weight loss of the mulberry agent container after excluding water, and the dissolution rate of the active ingredient was determined by chemically analyzing the total concentration of phosphate ions as an active ingredient in the circulating water and then checking the elution amount.

amount ! B: Weight of gel drug container at the time of measurement the law of nature Active ingredient dissolution rate (%) = -x 1o.

However, 0: weight of phosphorus initially contained in the gel drug; ■): weight of phosphorus eluted into the circulating water system by the time of measurement; 1st group]7. 3 The results are shown in the graph of Figure 4, and it was confirmed that the mm velocity of the gel-like drug and the dissolution rate of the effective ingredient completely matched, and that only the active ingredient was not eluted. The continuous cooling tower operation was stopped for 137 hours during the shutdown period, but there was no elution of the drug at all during this period.
)Ta.

Historically, as shown in the graph shown in Figure 5, the concentration of phosphate ions, which are the active ingredients in circulating water, has increased by 5 days after the start of cooling tower operation.
After that, the scattering loss and the supply line were in equilibrium, and the concentration remained constant during the period.

From the above facts, it has been demonstrated that according to the drug supply method according to the present invention, drugs can be continuously supplied to the circulating water system over a long period of time.

It should be noted that the method for specifically implementing the present invention is not limited to only one method shown in the examples, but for example,
The material of the drug container is not limited to foamed sterol, but it can also be made of other plastics or metals, and the interior may be filled with foamed sterol or an air chamber may be provided so that the overall ratio N is 1 or less. Furthermore, the container body and the lid may be joined by fitting or the like. Furthermore, a through hole V on two sides of the container,
j) It does not have to be one piece; the diameter is determined by the surface area of the gel-like drug and the period for which it is to be retained; however, one piece is sufficient for ease of design and production. The location is also arbitrary.

Furthermore, the types of active ingredients to be included in the gel drug may be reduced or added based on the analysis of circulating water in advance to predict the problems that will occur.

f, the distance from the surface of the gel drug in terms of the weight of the upper lid, i.e.
The volume of the space (inlet) has almost no effect on the drug supply speed, and even if the amount of drug (1) decreases and the space <A) becomes thicker, it remains constant as shown in the example. It is. Note that the gel-like drug can also be filled and injected through the through-hole of the container.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of the present invention when the container is in use, Figure 2 is a top view of the container, Figure 5 is a plan view of the inside of the container body, and Figure 4 is a diagram showing the dissolution of the active ingredient and gel drug respectively. A graph comparing the ratios, and FIG. 5 is a graph showing changes in the concentration of the active ingredient. (5) is a gel-like drug, (A) is a space inside the container, (7
) is a projecting edge, (8) is a water receiving surface, and (9) is a through hole. Patent applicant Hiroshi Nakamura, agent of Kuchizuka Kako Co., Ltd., patent attorney. Figure 1 Figure 23 'JN Kaisho 58-143833 (5) Figure 2

Claims (6)

[Claims] (1) A drug container containing a gel-like drug containing an effective drug is placed in a container having a through hole on the upper surface and is filled with an upper space at a spray water receiving point in the cooling tower, The gel-like drug is dissolved in the space by the inflowing spray water, and the solution is exchanged with the inflow water from the through hole outside the vessel (overflowing to elute the active ingredient into the circulating water of the cooling tower). A method for supplying a chemical to a cooling tower circulating water system, characterized in that: (2) A container for supplying a drug to a cooling tower circulating water system, in which a gel-like drug containing an effective drug is fixed and housed in a container having a through hole in the upper surface with a space below the through hole. (3) The overall specific gravity is reduced to 1 or less and it floats on the water surface in the cooling tower. 1: The container according to claim 2, which is disclosed herein. (4) The container according to claim 2 or 3, wherein a projecting edge is provided on the upper surface surrounding the through hole. (5) The method for supplying a drug according to claim 1, wherein the gelling substance of the gel-like drug is polyethylene glycol, and the siliceous polyethylene glycol is at least 25 parts by weight. (6) The container according to claim 2, wherein the gelling substance of the gel-like drug is polyethylene glycol, and the polyethylene glycol is at least 25 parts by weight.