JP2016148094A - Initial treatment agent for circulating cooling water and initial treatment method of circulating cooling water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an initial treatment agent for circulating cooling water capable of providing anticorrosive effects and scale prevention effects as a single agent while reducing phosphorus concentration and zinc concentration necessary for initial corrosion resistant film formation.SOLUTION: There is provided an initial treatment agent for circulating cooling water for forming an initial corrosion resistant coating film on a metal member surface of water system by adding it to the water system when activation of a circulating cooling water system, manufactured by combining a phosphor compound and a zinc compound and a copolymer of acrylic acid and hydroxy allyloxy propane sulphonic acid and or a salt thereof (AA/HAPS-based polymer) as a single agent. The initial treatment agent is added so that total phosphorus concentration in terms of POin the water system is 15 to 30 mgPO/L, zinc concentration is 5 to 20 mgZn/L and AA/HAPS-based polymer concentration in terms of POis 20 to 60 mgsoild/L.SELECTED DRAWING: Figure 1

Description

  The present invention provides an initial treatment agent for forming an initial anticorrosion film on the surface of a metal member of the aqueous system by adding to the circulating cooling water when starting up a new plant or restarting the plant, and a circulating cooling water system. It relates to an initial processing method.

Conventionally, as a water treatment method for a circulating cooling water system at the time of new factory operation or at the time of re-operation after an operation stoppage period for periodic repairs, Patent Document 1 discloses a total phosphorus concentration of 70 to 120 mg PO ₄ / L in the water system. A method of forming an initial anticorrosive film on the surface of a metal member such as a heat exchanger by adding a phosphate and a zinc compound so that the zinc concentration is 10 to 30 mg Zn / L has been proposed.
This Patent Document 1 discloses a calcium phosphate composed of an anticorrosive component and water-based calcium, such as when a high temperature portion is generated depending on the condition of the treatment target (for example, when an initial anticorrosion film is formed while operating a heat exchanger). Low molecular weight polymers such as acrylic acid polymers as polymer electrolytes that have the effect of precipitating and / or preventing the deposition of calcium phosphate scales to prevent adverse effects due to excessive deposition and adhesion of metallic scales on the surface of metal members Is added as a solid content of about 50 to 300 mg / L.

JP 2011-202243 A

In recent years, there has been a demand for a reduction in phosphorus and zinc concentrations in wastewater due to the strengthening of wastewater regulations. For this reason, it is desirable to reduce the phosphorus and zinc concentrations for the formation of initial anticorrosion coatings in circulating cooling water systems. ing.
In addition, in order to simultaneously perform the treatment for forming the initial anticorrosive film and the measure for scale, at least three water treatment chemicals of phosphate, zinc compound, and low molecular weight polymer are required. Since complicated labor is required for chemical management etc., the improvement is also desired.

  The present invention relates to an initial treatment agent for circulating cooling water and an initial processing method for the circulating cooling water system that can reduce the phosphorus concentration and the zinc concentration for forming an initial anticorrosive film in the circulating cooling water system and also obtain a scale prevention effect. The issue is to provide.

As a result of repeated studies to solve the above problems, the present inventor has added a specific low molecular weight polymer together with a phosphorus compound and a zinc compound, so that a phosphorus concentration and a zinc concentration necessary for forming an initial anticorrosion film are obtained. It has been found that it is possible to reduce the scale and to obtain a scale prevention effect.
The present invention has been achieved based on such findings, and the gist thereof is as follows.

[1] An initial treatment agent for forming an initial anticorrosive film on the surface of a metal member of the water system by adding to the water system at the time of starting the circulating cooling water system, comprising a phosphorus compound, a zinc compound, acrylic acid and a hydroxy aliquot An initial treatment agent for circulating cooling water, characterized by being formed into a single component with a copolymer of loxypropanesulfonic acid and / or a salt thereof (hereinafter referred to as “AA / HAPS polymer”).

[2] In [1], the AA / HAPS polymer has a molar ratio of a structural unit derived from acrylic acid and a structural unit derived from hydroxyallyloxypropanesulfonic acid and / or a salt thereof in a molar ratio of 70 to 90: An initial treatment agent for circulating cooling water, which is a copolymer having a weight average molecular weight of 1,000 to 400,000, contained at a ratio of 10 to 30.

[3] In [1] or [2], the phosphorus compound is one or more selected from the group consisting of orthophosphoric acid, hexametaphosphoric acid, phosphonic acid, and salts of these acids, and the zinc compound Is an initial treatment for circulating cooling water, characterized in that is zinc chloride and / or zinc sulfate.

[4] In any one of [1] to [3], an aqueous solution containing 5 to 20 wt% of the phosphorus compound, 2 to 10 wt% of the zinc compound, and 5 to 30 wt% of the AA / HAPS polymer. An initial treatment agent for circulating cooling water, characterized by

[5] An initial treatment method for forming an initial anticorrosive film on the surface of a metal member of the water system at the time of starting the circulating cooling water system, wherein the phosphorus compound and the zinc compound, acrylic acid and hydroxyallyloxypropane sulfonic acid and / or the same A copolymer with salt (hereinafter referred to as “AA / HAPS polymer”) has a total phosphorus concentration in terms of PO ₄ in the aqueous system of 15 to 30 mg PO ₄ / L, a zinc concentration of 5 to 20 mg Zn / L, AA / HAPS system polymer is added so that the concentration becomes 20 to 60 mg solid / L.

[6] In [5], the AA / HAPS polymer has a molar ratio of a structural unit derived from acrylic acid and a structural unit derived from hydroxyallyloxypropanesulfonic acid and / or a salt thereof in a molar ratio of 70 to 90: An initial treatment method for a circulating cooling water system, characterized in that it is a copolymer having a weight average molecular weight of 1,000 to 400,000, contained in a proportion of 10 to 30.

[7] In [5] or [6], the phosphorus compound is one or more selected from the group consisting of orthophosphoric acid, hexametaphosphoric acid, phosphonic acid, and salts of these acids, and the zinc compound Is an initial treatment method for a circulating cooling water system, characterized in that is zinc chloride and / or zinc sulfate.

[8] The initial treatment method for a circulating cooling water system according to any one of [5] to [7], wherein the calcium hardness of the aqueous system is adjusted to 50 to 150 mg CaCO ₃ / L.

[9] In any one of [5] to [8], 150 to 300 mg / L of the initial treatment agent for circulating cooling water according to any one of claims 1 to 4 is added to the aqueous system. Initial processing method for circulating cooling water system.

According to the present invention, it is possible to reduce the phosphorus concentration and the zinc concentration for forming the initial anticorrosive film in the circulating cooling water system, and it is possible to simultaneously obtain the scale preventive effect as well as the anticorrosive effect by the anticorrosive film formation.
According to the initial treatment agent for circulating cooling water of the present invention, the above-mentioned effects can be obtained with a single agent, and labor related to drug addition, chemical injection control, chemical management, etc. can be greatly reduced.

It is a schematic diagram which shows the structure of the heat-transfer surface evaluation test apparatus used in the Example. It is a schematic diagram which shows the structure of the corrosion rate measuring apparatus used in the Example.

  Hereinafter, embodiments of the present invention will be described in detail.

[Initial treatment method for circulating cooling water system]
An initial treatment method for a circulating cooling water system according to the present invention is an initial processing method for forming an initial anticorrosive film on the surface of a metallic member of the aqueous system when the circulating cooling water system is started, and includes a phosphorus compound, a zinc compound, acrylic acid and hydroxy A copolymer with allyloxypropanesulfonic acid and / or a salt thereof (hereinafter referred to as “AA / HAPS polymer”) has a total phosphorus concentration of 15 to 30 mg PO ₄ / L in terms of PO ₄ in the aqueous system, zinc The concentration is 5 to 20 mg Zn / L, and the concentration of the AA / HAPS polymer is 20 to 60 mg solid / L (“mg solid / L” indicates the pure mg / L concentration of the AA / HAPS polymer). It is characterized by adding to.
In addition, as a metal member made into object by this invention, an iron-type metal member, especially a carbon steel member are suitable. As the circulating cooling water system, an open circulating cooling water system is suitable.

The above-mentioned Patent Document 1 describes the addition of an acrylic acid-based polymer, but Patent Document 1 does not disclose details of the acrylic acid-based polymer to be used, and phosphorus compounds, zinc compounds, and AA. There is no description that the / HAPS polymer is added as a single agent, and it is suggested that the addition of the AA / HAPS polymer together with the phosphorus compound and the zinc compound can reduce the amount of the phosphorus compound and the zinc compound necessary for forming the initial anticorrosion film There is no description to do.
In the present invention, when an AA / HAPS polymer is added together with a phosphorus compound and a zinc compound, among the low molecular weight polymers, the total phosphorous concentration and zinc concentration for forming the initial anticorrosive film are not added when the AA / HAPS polymer is not added. It was achieved based on the new knowledge that it can be significantly reduced compared to

In the present invention, by using an AA / HAPS polymer together with a phosphorus compound and a zinc compound, a sufficient anticorrosion effect can be obtained even when the total phosphorus concentration and zinc concentration in the aqueous system are low. The amount of zinc compound used can be greatly reduced as compared with the case where no AA / HAPS polymer is used in combination, and sufficient anticorrosive effect can be obtained with the concentration of these components in the aqueous system being lower. Therefore, there are the following advantages.
(1) It is possible to suppress the use amount of components that are burdensome on the environment such as phosphorus compounds and zinc compounds.
(2) Conventionally, when a thermal load is applied, it is necessary to add an excessive low molecular weight polymer in order to suppress the scale of calcium phosphate. If the polymer concentration in the aqueous system is increased to prevent scale, the low molecular weight polymer However, in the present invention, the use of the AA / HAPS polymer can reduce the amount of the phosphorus compound, thereby reducing the amount of the low molecular weight polymer. The gelation of the low molecular weight polymer can be prevented.
(3) In the conventional method, it was necessary to add a total phosphorus concentration of 100 mg PO ₄ / L, a zinc concentration of 20 mg Zn / L, and a low molecular weight polymer concentration of about 60 mg solid / L. It was 1000 mg / L and was not realistic. For this reason, conventionally, it was added in three parts without being made into one agent, but according to the present invention, since the use concentration of each component can be suppressed, it becomes possible to make one agent, and drug management and chemical injection Handling becomes easier.

<AA / HAPS polymer>
The AA / HAPS polymer is another low molecular weight polymer such as a copolymer of acrylic acid (AA) and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) (hereinafter referred to as “AA / AMPS polymer). In terms of having a higher corrosion-inhibiting effect (capability of forming an initial treatment film) than that of a low molecular weight polymer used in combination with a phosphorus compound and a zinc compound, it is extremely effective.

The AA / HAPS polymer includes a structural unit derived from acrylic acid (AA) and a structural unit derived from a HAPS salt such as hydroxyallyloxypropane sulfonic acid (HAPS) and / or an alkali metal salt such as a sodium salt thereof. A copolymer having a molar ratio (AA: HAPS molar ratio) of 70 to 90:10 to 30 and a weight average molecular weight of 1,000 to 400,000 is preferable.
When the AA: HAPS molar ratio and the molecular weight are outside the above ranges, a good scale preventing effect cannot be obtained, and the total phosphorus concentration and zinc necessary for obtaining the anticorrosive effect in combination with the phosphorus compound and the zinc compound. The concentration cannot be reduced.
The AA / HAPS molar ratio of the AA / HAPS polymer is more preferably 70 to 90:10 to 30. The weight average molecular weight of the AA / HAPS polymer is more preferably 5,000 to 50,000. In addition, the said weight average molecular weight is a value of standard polyacrylic acid conversion by gel permeation chromatography (GPC method).

  Two or more AA / HAPS polymers having different AA / HAPS molar ratios and weight average molecular weights may be used.

<Phosphorus compound>
Examples of the phosphorus compound include orthophosphoric acid and / or a salt thereof such as sodium phosphate, potassium phosphate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, sodium dihydrogen phosphate, potassium dihydrogen phosphate, 1- Phosphonic acid and / or salt thereof such as hydroxyethylidene-1,1-diphosphonic acid (HEDP), 2-phosphonobutane-1,2,3-tricarboxylic acid (PBTC), aminotrimethylphosphonic acid, pyrophosphoric acid and / or salt thereof , Polymerized phosphoric acid such as tripolyphosphoric acid and / or salt thereof, hexametaphosphoric acid and / or salt thereof, alkali metal pyrophosphate such as potassium pyrophosphate and sodium pyrophosphate, alkali hexametaphosphate such as sodium hexametaphosphate and potassium hexametaphosphate Metal salt, dihydrogen pyrophosphate dinatrate It can be used dihydrogen pyrophosphate salts such as beam. These may be used alone or in combination of two or more.
Of these, orthophosphoric acid and / or its alkali metal salt, hexametaphosphoric acid and / or its alkali metal salt, phosphonic acid and / or its alkali metal salt are preferred as materials capable of promoting the formation of the anticorrosive film.

<Zinc compound>
As a zinc compound, zinc salts, such as zinc chloride and zinc sulfate, are suitable, and also about a zinc compound, 1 type may be used independently and 2 or more types may be used together.

<Initial processing>
In the present invention, when starting the circulating cooling water system, a phosphorus compound, a zinc compound and AA / HAPS-based polymer, the total phosphorus concentration of PO ₄ in terms in circulating cooling water system 15~30mgPO ₄ / L, zinc concentration 5~20mgZn / L, added so that the concentration of AA / HAPS polymer is 20 to 60 mg solid / L.
If the total phosphorus concentration and the zinc concentration are lower than the lower limit of the above range, a sufficient anticorrosive effect cannot be obtained. If it exceeds the upper limit of the above range, the object of the present invention for reducing the total phosphorus concentration and zinc concentration cannot be achieved.
That is, in the above-mentioned Patent Document 1, the total phosphorus concentration is 70 to 120 mg PO ₄ / L, and the zinc concentration is 10 to 30 mg Zn / L. In the present invention, such a combination of AA / HAPS polymers is used. Compared to conventional methods, the total phosphorus concentration is 15-30 mg PO ₄ / L, the zinc concentration is 5-20 mg Zn / L, and the total phosphorus concentration necessary for the formation of the initial anticorrosion film can be reduced by about 70%. The density can also be reduced by about 50%.

  Moreover, when the addition concentration of the AA / HAPS polymer is less than the lower limit of the above range, the effect of preventing scale by the AA / HAPS polymer and the effect of reducing the total phosphorus concentration and the zinc concentration cannot be obtained sufficiently. When the concentration of the AA / HAPS polymer added is higher than the above upper limit, phosphorus or zinc, which are anticorrosive components, is excessively dispersed in water, making it difficult to use as an anticorrosive film.

In the present invention, a phosphorus compound, calcium hardness of the circulating cooling water system of adding a zinc compound and AA / HAPS-based polymer 50~150mgCaCO ₃ / L, to be particularly 50~100mgCaCO ₃ / L, in terms of the scale prevention effect preferable.
If the aqueous calcium hardness is too high, a sufficient scale prevention effect may not be obtained. When the aqueous calcium hardness is low, there is almost no problem of scale precipitation, but an anticorrosion film composed of phosphorus and calcium produced by the action of the added phosphorus compound and calcium cannot be sufficiently formed, and the anticorrosion effect is inferior. There is a risk of becoming something. Therefore, in the present invention, it is preferable to control the concentration by blow or the like so as to achieve the above calcium hardness. If the quality of the water system to be treated is out of the above range even after adjusting the amount of blown water, the water quality may be adjusted by adding or removing calcium hardness components such as calcium nitrate and calcium chloride.

  Moreover, it is preferable that pH of the water system at the time of performing an initial stage treatment by this invention is 6.0-7.0. When the pH is higher than the above upper limit, there is little elution of iron from the iron-based metal member, and therefore iron phosphate as a corrosion protection film component cannot be sufficiently formed on the surface of the iron-based metal member, and if lower than the above lower limit, Corrosion becomes stronger, and there is concern about the progress of temporary corrosion of the metal to be treated and other metal materials present in the system. Although there is no restriction | limiting in particular in the adjustment method of pH, The method of adding and adjusting acids, such as hydrochloric acid and a sulfuric acid, is preferable.

Further, in the present invention, a phosphorus compound, was added zinc compound and AA / HAPS-based polymer, M alkalinity of water that the initial pH was adjusted to the range is preferably 10~40mgCaCO ₃ / L.

  The initial processing is usually performed at room temperature.

  In the present invention, the period of performing the initial treatment step of adding the phosphorus compound, zinc compound and AA / HAPS polymer so as to be in the above-mentioned concentration range as described above at the start of the circulating cooling water system is 24 to 96 hours, particularly 24 It is preferable to set it to about -48 hours. If this initial treatment time is too short, an anticorrosive film having an excellent anticorrosion effect cannot be formed, and if it is too long, an effect commensurate with the treatment time cannot be obtained.

[Initial treatment agent for circulating cooling water]
The initial treatment agent for circulating cooling water of the present invention is suitably used for the above-described initial processing method of the circulating cooling water system of the present invention, and includes the above-mentioned phosphorus compound, zinc compound and AA / HAPS polymer. It is made into a drug.

  Preferably, the initial treating agent of the present invention is an aqueous solution containing 5 to 20% by weight of the phosphorus compound, 2 to 10% by weight of the zinc compound, and 5 to 30% by weight of the AA / HAPS polymer. The initial treatment agent of the present invention as such a one-part preparation is added to the circulating cooling water system at 150 to 300 mg / L, and the total phosphorus concentration, zinc concentration and AA / HAPS polymer concentration in the circulating cooling water system are set as described above. It is preferable to implement the initial treatment method of the present invention by setting the concentration range.

  The initial treatment agent of the present invention includes agents other than phosphorus compounds, zinc compounds, and AA / HAPS polymers, such as calcium compounds for adjusting calcium hardness and pH adjustment, as long as the object of the present invention is not impaired. The acid may be included.

  Hereinafter, the present invention will be described more specifically with reference to examples.

[Additives]
In the following examples and comparative examples, the details of the polymers used for the preparation of the initial treating agent are as follows.

AA / HAPS polymer I: AA: HAPS molar ratio 80:20, weight average molecular weight 10,000 polymer AA / HAPS polymer II: AA: HAPS molar ratio 90:10, weight average molecular weight 10,000 Polymer of AA / HAPS polymer III: AA: HAPS molar ratio of 65:35 and weight average molecular weight of 10,000 AA / AMPS polymer I: AA: AMPS molar ratio of 80:20 and weight average molecular weight of 10 Polymer of 1,000, MA polymer I: homopolymer of maleic acid having a weight average molecular weight of 1,000

[Evaluation of anticorrosion effect]
[Example 1]
<Preparation of initial treatment agent>
A mixture of phosphonic acid: orthophosphoric acid = 1: 1 (weight ratio) (hereinafter referred to as “mixed phosphorus compound”) is 20 wt% (total phosphoric acid concentration), zinc chloride is 10 wt% (total zinc concentration), AA / Initial treatment agent 1 of the present invention comprising an aqueous solution containing 35 wt% (total solid content concentration) of HAPS polymer I was prepared.

<Test water>
Nokimachi water (calcium hardness 40 mg CaCO ₃ / L, M alkalinity 40 mg CaCO ₃ / L) added with 10% calcium hardness aqueous solution (calcium chloride aqueous solution) so that the calcium hardness is 60 mg CaCO ₃ / L did. The pH of the test water is 6.0 and the M alkalinity is 30 mg CaCO ₃ / L.

<Test equipment>
The heat transfer surface evaluation test apparatus shown in FIG. 1 was used.
In this test apparatus, test water in a test water tank (100 L capacity) 1 is circulated in a test tube 3 in which an iron evaluation tube 2 is inserted and immersed with a circulating water pump P ₁ and circulation lines L ₁ and L _2. It is something to be made. The circulation return lines L ₂ flow regulating valve V is provided. The evaluation tube 2 is heated by a heater (thermocouple) 4.
Reference numeral 5 denotes a make-up water tank (300 L capacity), and water in the make-up water tank 5 is supplied to the test water tank 1 through the make-up water line L ₃ by the test water supply pump P ₂ as necessary. L ₄ is an overflow line.

<Test conditions>
It heated with the heater 4 and adjusted so that the internal temperature of the evaluation tube 2 might be set to 90 degreeC. The flow rate of the test water was 0.5 m / s, and the initial treatment period was 2 days.
The test was performed by adding 200 mg / L of the initial treatment agent 1 to the test water in the test water tank 1, and the corrosion weight loss of the evaluation tube 2 after the test was measured.
In addition, what added 200 mg / L of the initial treatment agent 1 to test water has a total phosphorus concentration of 20 mg PO ₄ / L in terms of PO ₄ , a zinc chloride concentration of 10 mg Zn / L, and an AA / HAPS polymer I concentration of 35 mg solid / L.
The results are shown in Table 1.

[Example 2]
The test was conducted in the same manner as in Example 1 except that 300 mg / L of the initial treatment agent 1 was added to the test water, and the mixed phosphorus compound, zinc chloride and AA / HAPS polymer I concentrations in the test water were as shown in Table 1. The results are shown in Table 1.

[Comparative Example 1]
The test was conducted in the same manner as in Example 1 without adding the initial treating agent 1 to the test water, and the results are shown in Table 1.

[Comparative Example 2]
The test was conducted in the same manner as in Example 1, except that 100 mg / L of the initial treatment agent 1 was added to the test water, and the mixed phosphorus compound, zinc chloride and AA / HAPS polymer I concentrations were as shown in Table 1. The results are shown in Table 1.

[Comparative Example 3]
Instead of the initial treatment agent 1, a test was performed in the same manner as in Example 1, except that 100 mg PO ₄ / L of hexametaphosphoric acid, 20 mg Zn / L of zinc chloride, and 60 mg solid / L of AA / AMPS polymer were added to the test water. The results are shown in Table 1.

  From Table 1, it can be seen that by adding the initial treatment agent of the present invention so as to have a predetermined concentration, it is possible to obtain a high anticorrosive effect while reducing the aqueous phosphorus concentration and zinc concentration.

[Evaluation of scale suppression effect]
[Example 3]
<Preparation of initial treatment agent>
As in Example 1, an aqueous solution containing 20% by weight (total phosphoric acid concentration) of the mixed phosphorus compound, 10% by weight (total zinc concentration) of zinc chloride, and 35% by weight (total solid concentration) of AA / HAPS polymer I An initial treatment agent 1 of the present invention was prepared.

<Test water>
Nokimachi water (calcium hardness 40 mg CaCO ₃ / L, M alkalinity 40 mg CaCO ₃ / L) added with 10% calcium hardness solution (calcium chloride solution) to give a calcium hardness of 50 mg CaCO ₃ / L did. The pH of the test water is 6.2 and the M alkalinity is 30 mg CaCO ₃ / L.

<Test equipment>
As in Example 1, the heat transfer surface evaluation test apparatus shown in FIG. 1 was used.

<Test conditions>
It heated with the heater 4 and adjusted so that the internal temperature of the evaluation tube 2 might be set to 90 degreeC. The flow rate of the test water was 0.5 m / s, and the initial treatment period was 2 days.
The test was performed by adding 200 mg / L of the initial treatment agent to the test water in the test water tank 1, the amount of scale adhered to the evaluation tube 2 after the test was measured, and the adhesion rate was calculated.
The results are shown in Table 2.
The target value of the scale deposition rate is 20 mg / cm ² / month or less.

[Examples 4 to 6, Reference Examples 1 and 2]
In preparing the test water, the test was performed in the same manner as in Example 3 except that the test water having the calcium hardness shown in Table 2 was adjusted by adding 10% calcium hardness solution. Indicated.

From Table 2, it can be seen that a good scale inhibiting effect can be obtained by the initial treatment agent of the present invention at a calcium hardness of 50 to 150 mg CaCO ₃ / L.

[Evaluation of anti-corrosion effect and scale suppression effect]
[Examples 7 to 11, Reference Example 3, Comparative Examples 4 to 6]
<Preparation of initial treatment agent>
Initial treatment agents 2 to 8 comprising aqueous solutions containing mixed phosphorus compounds, phosphonic acid or orthophosphoric acid, zinc chloride, and polymers shown in Table 3 at concentrations shown in Table 3 were prepared. The mixed phosphorus compound, phosphonic acid, and orthophosphoric acid concentrations are total phosphoric acid concentrations, the zinc chloride concentration is the total zinc concentration, and the polymer concentration is the total solid content concentration.

Incidentally, what the initial treatment agent 2-8 was added 200 mg / L in the test water, the total phosphorus concentration 20mgPO ₄ / L of PO ₄ in terms of zinc concentration 10mgZn / L chloride, polymer concentration 35mgsolid / L becomes, 100 mg / L added is ones, total phosphorus concentration 10mgPO ₄ / L of PO ₄ in terms of zinc concentration 5mgZn / L chloride, polymer concentration 17.5mgsolid / L, and the material obtained by adding 80 mg / L, the total phosphorus concentration of PO ₄ in terms 8mgPO ₄ / L, zinc chloride concentration 4 mg Zn / L, polymer concentration 14 mg solid / L.

{Evaluation of anticorrosion effect}
<Test water>
1) initial processing period pure water, 10% calcium hardness solution (calcium chloride solution), 10% aqueous solution of magnesium (aqueous magnesium sulfate solution), 5% M alkalinity solution (aqueous sodium bicarbonate), respectively 60mgCaCO _3, 30mgCaCO ₃ / L, 60 mg CaCO ₃ / L. The pH of this test water is 8.0.
The initial treating agent shown in Table 4 was added to the test water at a predetermined concentration shown in Table 4.
This test water was used as an initial treatment liquid.
2) Corrosion acceleration period Nogimachi water (calcium hardness 40 mg CaCO ₃ / L, M alkalinity 40 mg CaCO ₃ / L, chloride, sulfate ions 20 mg / L each), 10% chloride ion solution (sodium chloride solution), 10% A sulfate ion solution (sodium sulfate solution) was added so that the chloride ion concentration and the sulfate ion concentration were 100 mg / L, respectively.
This test water was used as a corrosion accelerating solution.

<Test method>
The corrosion rate measuring apparatus shown in FIG. 2 was used.
As shown in FIG. 2, each initial processing liquid is put in a 1 L beaker 10, and an SS sensor 11 (SS400 (10φ × 30 mm)), a SUS sensor 12 (SUS (10φ × 30 mm)), and a SUS sensor 13 (SUS (10φ) × 30 mm)) was set, and stirring was started with a stirrer 14 at room temperature.
Two days later, the test water was switched to the corrosion accelerating solution, and stirring was further performed for 1 day.
Thereafter, the corrosion rate (mdd) was measured using a corrosion meter (manufactured by Toho Giken).

{Evaluation of scale suppression effect}
<Test water>
In Nogicho water, 10% calcium hardness aqueous solution (calcium chloride aqueous solution), 10% magnesium aqueous solution (magnesium sulfate aqueous solution), 5% M alkalinity aqueous solution (sodium bicarbonate aqueous solution), 60 mgCaCO ₃ , 30 mgCaCO ₃ / L, 60 mgCaCO, respectively. It added so that it might become ₃ / L.
The initial treating agent shown in Table 4 was added to the test water at the addition concentration shown in Table 4.

<Test method>
Using heat transfer surface test apparatus shown in FIG. 1, the residence time of the test water tank 1 is supplemented with the test water via makeup water line L ₃ by the test water supply pump P ₂ such that 24 hours.
The evaluation tube 2 was heated by the heater 4 so that the internal temperature became 90 ° C. The test water was 0.5 m / s and passed for 48 hours.
After completion of the test, the evaluation tube 2 was removed, and the adhering material adhering to the heat transfer surface was dried, and the weight was measured. The scale deposition rate (mg / cm ² / month = mcm) was calculated from the result of the amount of deposits.

{Test results}
The test results are shown in Table 4.

Table 4 shows the following.
In Examples 7 to 11, both the corrosion rate and the scale adhesion rate are maintained at a low level, and it can be seen that a good anticorrosive film is formed by using the AA / HAPS polymer. In Reference Example 3, the AA / HAPS molar ratio of the used AA / HAPS polymer is outside the preferred range of the present invention, and the scale suppression effect is good, but the corrosion rate is high. In Comparative Example 4, an AA / AMPS polymer was used instead of the AA / HAPS polymer, and the scale suppression effect was still good, but the corrosion rate was high. In Comparative Example 5 using the MA homopolymer, the corrosion rate is kept low, but the scale suppressing effect on the heat transfer surface is insufficient, which is not realistic.
The comparative example 6 shows the case where the addition amount of the initial treatment agent of the present invention is small, and it can be seen that it is necessary to add to a predetermined concentration or more in order to obtain the anticorrosion effect and the scale suppression effect.
From the above results, it can be seen that the initial treatment effect of the initial treatment agent of the present invention using an AA / HAPS polymer, preferably an AA / HAPS polymer having a predetermined AA / HAPS molar ratio, is excellent.

DESCRIPTION OF SYMBOLS 1 Test water tank 2 Evaluation tube 3 Test tube 4 Heater 5 Supply water tank 10 Beaker 11 SS sensor 12 SUS sensor 13 SUS sensor 14 Stirrer 15 Corrosion meter

Claims (9)

An initial treatment agent for forming an initial anticorrosive film on the surface of a metal member of the water system by adding to the water system at the start of the circulating cooling water system,
The phosphorous compound and the zinc compound, and a copolymer of acrylic acid and hydroxyallyloxypropane sulfonic acid and / or a salt thereof (hereinafter referred to as “AA / HAPS polymer”) are formed into a single agent. An initial treatment agent for circulating cooling water.   In Claim 1, the said AA / HAPS type | system | group polymer is 70-90: 10-30 by molar ratio with the structural unit derived from acrylic acid, and the structural unit derived from hydroxyallyloxypropane sulfonic acid and / or its salt. An initial treatment agent for circulating cooling water, characterized in that it is a copolymer having a weight average molecular weight of 1,000 to 400,000.   3. The phosphorus compound according to claim 1, wherein the phosphorus compound is one or more selected from the group consisting of orthophosphoric acid, hexametaphosphoric acid, phosphonic acid, and salts of these acids, and the zinc compound is zinc chloride and / or Or the initial processing agent for circulating cooling water characterized by being zinc sulfate.   4. The aqueous solution according to claim 1, wherein the phosphorus compound is 5 to 20% by weight, the zinc compound is 2 to 10% by weight, and the AA / HAPS polymer is 5 to 30% by weight. Characteristic initial treatment agent for circulating cooling water. An initial treatment method for forming an initial anticorrosive film on the surface of a metal member of the water system when the circulating cooling water system is started,
A phosphorus compound and a zinc compound, and a copolymer of acrylic acid and hydroxyallyloxypropane sulfonic acid and / or a salt thereof (hereinafter referred to as “AA / HAPS polymer”) are all PO ₄ converted in the aqueous system. An initial treatment method for a circulating cooling water system comprising adding a phosphorus concentration of 15 to 30 mg PO ₄ / L, a zinc concentration of 5 to 20 mg Zn / L, and an AA / HAPS polymer concentration of 20 to 60 mg solid / L .   In Claim 5, the said AA / HAPS type | system | group polymer is 70-90: 10-30 in the molar ratio with the structural unit derived from acrylic acid, and the structural unit derived from hydroxyallyloxypropane sulfonic acid and / or its salt. An initial treatment method for a circulating cooling water system, wherein the copolymer has a weight average molecular weight of 1,000 to 400,000 and is contained in a ratio of   7. The phosphorus compound according to claim 5, wherein the phosphorus compound is one or more selected from the group consisting of orthophosphoric acid, hexametaphosphoric acid, phosphonic acid, and salts of these acids, and the zinc compound is zinc chloride and / or Or the initial processing method of the circulating cooling water system characterized by being zinc sulfate. The initial treatment method for a circulating cooling water system according to any one of claims 5 to 7, wherein the calcium hardness of the aqueous system is adjusted to 50 to 150 mg CaCO ₃ / L.   The circulation according to any one of claims 5 to 8, wherein the initial treatment agent for circulating cooling water according to any one of claims 1 to 4 is added to the aqueous system at 150 to 300 mg / L. Initial treatment method for cooling water system.

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