JP4495394B2 - Corrosion inhibitor injection method - Google Patents

Description

【００４６】
表１から明らかなように、モルホリン脂肪酸塩からなる腐食抑制剤を給水へ薬注したほうが蒸気配管，蒸気ヘッダおよび復水配管へ薬注するよりも腐食速度が大きく、腐食抑制効果が低いことが分かる。一般に、モルホリン脂肪酸塩からなる腐食抑制剤は、ボイラ中で蒸気中とボイラ水中とに分配される。そのため、蒸気配管および復水配管で腐食抑制効果を示すモルホリン脂肪酸塩からなる腐食抑制剤の量が薬注時より減少する。これにより、腐食抑制効果が弱まり、腐食速度が増加するのである。つまり、蒸気配管，蒸気ヘッダおよび復水配管へモルホリン脂肪酸塩からなる腐食抑制剤を薬注すると、給水へ薬注するモルホリン脂肪酸塩からなる腐食抑制剤より少ない薬注量で同等の腐食抑制効果を得ることができる。また、モルホリン脂肪酸塩からなる腐食抑制剤の脂肪酸部分は、被膜型防食剤として作用するため、蒸気配管，蒸気ヘッダおよび復水配管へモルホリン脂肪酸塩からなる腐食抑制剤を薬注することで、ボイラ内の水位電極に皮膜を形成して水位制御にトラブルを引き起こす可能性もなくすることができる。さらに、第二実施例のように、蒸気ヘッダへ薬注する場合には、薬注装置を１台設けるだけで良いので薬注装置の台数を減らすことができる。
【００４７】
【発明の効果】
以上のように、この発明によれば、蒸気配管および復水配管の防食に必要なモルホリン脂肪酸塩からなる腐食抑制剤を無駄無く薬注することができ、かつ水位制御のトラブルを引き起こさなくすることができる。
【図面の簡単な説明】
【図１】この発明の第一実施例を概略的に示す説明図である。
【図２】この発明の第二実施例を概略的に示す説明図である。
【図３】従来の薬注方法を概略的に示す説明図である。
【符号の説明】
１ ボイラ
２ 負荷機器
３ 蒸気配管
５ 復水配管
９ スチームトラップ
１１ 蒸気ヘッダ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a chemical injection method for a corrosion inhibitor.
[0002]
[Prior art]
Conventionally, there is a boiler facility that supplies steam to a load device from a boiler, collects steam after heat exchange in the load device as condensate, and reuses it as boiler feed water. In this type of boiler equipment, as shown in FIG. 3, the steam supplied from the boiler 21 to the load device 23 via the steam pipe 22 exchanges heat with the load device 23, and the condensate after the heat exchange is It is configured to be mixed with makeup water supplied from a makeup water pipe 26 in a water supply tank 25 via a condensate piping 24 and supplied to the boiler 21 from a water supply line 27.
[0003]
The steam pipe 22 and the condensate pipe 24 in this boiler facility are in contact with the steam and the condensate by the action of lowering the pH of the condensate by bicarbonate ions, carbon dioxide, etc. contained in the feed water, and the oxidizing action by dissolved oxygen. General corrosion and pitting corrosion may occur in the part where it occurs.
[0004]
As a measure for preventing the occurrence of this general corrosion and pitting corrosion, a chemical treatment for preventing corrosion is generally performed using chemicals. For chemical treatment, a method that uses a film-type anticorrosive to prevent corrosion of the pipe by forming a film on metal pipes, etc., or a neutralization-type anticorrosive that neutralizes acidic substances to prevent corrosion of the pipe There is a method using a corrosion inhibitor such as a method using.
[0005]
Here, this chemical treatment will be described with reference to FIG. First, the corrosion inhibitor is usually poured into the water supply line 27 that supplies the boiler 21 from the water supply tank 25 using the chemical injection device 28. Here, the problem is that the corrosion inhibitor is distributed in the steam and the boiler water in the boiler 21. That is, all of the corrosion inhibitor injected to prevent corrosion of the steam pipe 22 and the condensate pipe 24 does not flow into the steam pipe 22 and the condensate pipe 24 but remains in the boiler water, and the steam pipe 22 and the condensate pipe 24. There are corrosion inhibitors that are not involved in corrosion protection. Therefore, in order to inject into the boiler feed water in consideration of the corrosion inhibitor remaining in the boiler water, an excessive amount of infusion is being carried out.
[0006]
In addition, in the case where a film-type anticorrosive agent is used, there has been reported a case where a film is formed on a water level electrode (not shown) for controlling the water level in the boiler 21 and causes trouble in water level control. Yes.
[0007]
[Problems to be solved by the invention]
The problem to be solved by the present invention is to be able to inject a corrosion inhibitor necessary for preventing corrosion of steam pipes and condensate pipes without waste and not to cause trouble in water level control.
[0008]
[Means for Solving the Problems]
  This invention was made in order to solve the said subject, Comprising: The invention of Claim 1 isA boiler that generates steam by heating feed water, a load device that uses steam, a steam pipe for supplying steam to the load device, and a condensate obtained by condensing steam used in the load device In the boiler equipment having a condensate pipe for collecting and mixing with the feed water, the position of the uppermost stream side of the steam pipe and the condensate pipe on the downstream side of the steam trap provided in the condensate pipe Close to the steam trapIt is characterized by injecting a corrosion inhibitor composed of a morpholine fatty acid salt into either one or both.
[0009]
  Furthermore, the invention according to claim 2Used in a boiler that generates steam by heating feed water, a load device that uses steam, a steam pipe for supplying steam to the load device, a steam header provided in the steam pipe, and the load device In the boiler equipment provided with the condensate piping for collecting the condensate obtained by condensing the steam generated and mixing with the feed water, the steam header and the steam trap provided in the condensate piping on the downstream side The condensate pipe and the position near the steam trap 9It is characterized by injecting a corrosion inhibitor composed of a morpholine fatty acid salt into either one or both.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described. The present invention can be suitably implemented for corrosion prevention of steam pipes and condensate pipes in boiler equipment equipped with condensate pipes such as steam boilers. In the present invention, a corrosion inhibitor composed of a morpholine fatty acid salt is poured into one or both of a steam pipe and a condensate pipe.
[0011]
First, the steam piping will be described. Since this steam pipe is normally filled with steam during boiler operation, the possibility of corrosion is low. However, when the operation of the boiler is stopped, the temperature of the steam pipe is lowered, and the steam in the steam pipe is condensed into water. Carbon dioxide or the like dissolves in the condensed water to produce an acidic substance, which causes corrosion due to a decrease in pH.
[0012]
Next, the condensate piping will be described. The condensate pipe is provided with a steam trap, and the steam trap separates the water and steam condensed in the load device and discharges only water. Then, when carbon dioxide or the like dissolves in the condensed water, an acidic substance is generated, and corrosion due to a decrease in pH occurs.
[0013]
Therefore, in order to suppress corrosion due to this acidic substance, a corrosion inhibitor made of a morpholine fatty acid salt is injected. This morpholine fatty acid salt is decomposed by heat into morpholine and fatty acid, and morpholine acts as a neutralization type anticorrosive, and fatty acid acts as a film type anticorrosive, so both functions of neutralization and film action are achieved. It is a corrosion inhibitor. Here, examples of the fatty acid of the morpholine fatty acid salt include saturated fatty acids such as lauric acid, myristic acid, palmitic acid and stearic acid, and unsaturated fatty acids such as oleic acid, linoleic acid and linolenic acid.
[0014]
In order to prevent corrosion of the steam pipe and the condensate pipe, a corrosion inhibitor made of this morpholine fatty acid salt is used. As a chemical injection position of the corrosion inhibitor made of this morpholine fatty acid salt, it is preferable to carry out at the upstream side of the steam pipe. Moreover, in the boiler equipment provided with the steam header, it is preferable to pour the chemical into the steam header.
[0015]
First, a case where a corrosion inhibitor made of a morpholine fatty acid salt is poured on the upstream side of the steam pipe will be described. The steam pipe is easily corroded by an acidic substance. That is, it is considered that the portion where the steam containing the acidic substance exists is corroded when the steam is condensed. Therefore, it is possible to suppress corrosion of the steam pipe and all the pipes on the downstream side by injecting the chemical at the first position where the steam passes. That is, in order to suppress corrosion in all the pipes after the steam pipe, it is preferable to add a corrosion inhibitor made of a morpholine fatty acid salt as upstream as possible in the steam pipe.
[0016]
As an advantage of injecting a corrosion inhibitor made of morpholine fatty acid salt on the upstream side of the steam pipe, first, all the pipes after the steam pipe can be anticorrosive. That is, corrosion prevention of the steam pipe and the condensate pipe can be performed. Further, since the corrosion inhibitor made of morpholine fatty acid salt is poured into the steam pipe, it is possible to eliminate the possibility of causing trouble in water level control by forming a film on the water level electrode in the boiler. Further, since the corrosion inhibitor made of morpholine fatty acid salt is to be poured into the steam pipe, all the corrosion inhibitors made of morpholine fatty acid salt to be poured can be used as corrosion inhibitors, and the amount of evaporation of the boiler It is possible to administer medicines according to In other words, it is possible to inject medicine suitable for the amount of evaporation, and it is possible to prevent excessive medicine injection of a corrosion inhibitor made of morpholine fatty acid salt.
[0017]
Next, a case where a corrosion inhibitor composed of a morpholine fatty acid salt is poured into the steam header will be described. The steam header is a device that collects steam of one or more boilers and supplies the steam to one or more load devices. That is, the steam generated from each boiler is collected in the steam header. Therefore, by pouring into the steam header, corrosion of each steam pipe used for supplying from the steam header to a plurality of load devices can be suppressed at a time. Moreover, the said condensate piping after the said load apparatus passage can also be corroded simultaneously.
[0018]
As an advantage of injecting a corrosion inhibitor composed of a morpholine fatty acid salt into the steam header, first, the steam pipe and the condensate pipe from the steam header to the water supply tank can be collectively prevented. That is, since only a single chemical injection device is provided in the steam header, the corrosion of the piping until returning to the water supply tank can be prevented, so the number of chemical injection devices can be reduced. Further, since the corrosion inhibitor made of morpholine fatty acid salt is poured into the steam header, it is possible to eliminate the possibility of causing trouble in water level control by forming a film on the water level electrode in the boiler. Furthermore, since the corrosion inhibitor consisting of morpholine fatty acid salt will be injected into the steam header, all the corrosion inhibitors consisting of morpholine fatty acid salt to be injected can be used as a corrosion inhibitor, The medicine can be injected according to the evaporation amount. In other words, it is possible to inject medicine suitable for the amount of evaporation, and it is possible to prevent excessive medicine injection of a corrosion inhibitor made of morpholine fatty acid salt.
[0019]
In addition, there is a method in which a corrosion inhibitor composed of a morpholine fatty acid salt is poured into a steam pipe supplied from the steam header to the load device. In this case, a chemical injection device is provided for all the steam pipes from the steam header to the load device, and the chemicals are separately injected. Also in this method, the steam pipe and the condensate pipe can be protected from corrosion. Moreover, it is possible to eliminate the possibility of causing trouble in water level control by forming a film on the water level electrode in the boiler. And since all the said steam piping is poured, all the corrosion inhibitors which consist of morpholine fatty acid salts can be used as a corrosion inhibitor. Furthermore, since each medicine can be injected based on the amount of evaporation used by each load device, it is possible to prevent excessive injection of a corrosion inhibitor made of a morpholine fatty acid salt.
[0020]
There is also a method of pouring the condensate pipe after the load device. Also in this case, since the medicine is injected on the downstream side of the steam trap, a corrosion inhibitor made of a morpholine fatty acid salt can be used. Also in this method, the condensate pipe can be protected from corrosion. Moreover, it is possible to eliminate the possibility of causing trouble in water level control by forming a film on the water level electrode in the boiler. And since all the said condensate pipes are poured, all the corrosion inhibitors consisting of morpholine fatty acid salts can be used as corrosion inhibitors. Furthermore, since each medicine can be injected based on the amount of evaporation used by each load device, it is possible to prevent excessive injection of a corrosion inhibitor made of a morpholine fatty acid salt.
[0021]
Further, there is a method of pouring medicine into both the steam pipe and the condensate pipe. For example, when the total length of the steam pipe is long, a corrosion inhibitor composed of a morpholine fatty acid salt is consumed in the steam pipe, or a drain discharge means (not shown) for drain discharge provided in the middle of the steam pipe. When the corrosion inhibitor made of morpholine fatty acid salt is discharged together with water, the corrosion inhibitor made of morpholine fatty acid salt supplied to the condensate pipe may be reduced. In such a case, the corrosion of the condensate pipe is more effectively suppressed by injecting into the condensate pipe a portion of the consumption of the corrosion inhibitor composed of the morpholine fatty acid salt consumed in the steam pipe. Can do.
[0022]
As described above, according to the present invention, the corrosion inhibitor made of morpholine fatty acid salt necessary for corrosion prevention of steam pipes and condensate pipes can be poured without waste, and troubles in water level control can be prevented. be able to. In addition, in the case of pouring chemicals into the steam header, the number of chemical injection devices can be reduced.
[0023]
【Example】
Next, specific examples of the present invention will be described. FIG. 1 is an explanatory diagram schematically showing the configuration of the first embodiment of the present invention. These are merely examples, and do not limit the scope of the present invention.
[0024]
First, in FIG. 1, the boiler 1 and the load device 2 are connected by a steam pipe 3, the load device 2 and a feed water tank 4 are connected by a condensate pipe 5, and the feed water tank 4 and the lower part of the boiler 1 are connected. It is connected by a water supply pipe 7 provided with a water supply pump 6. Further, in the water supply tank 4, the makeup water supplied from the makeup water pipe 8 and the condensate supplied from the condensate pipe 5 are mixed. The condensate pipe 5 is provided with a steam trap 9, which separates steam and water and discharges only water. And the corrosion inhibitor which consists of morpholine fatty acid salt in this invention is poured into the said steam piping 3 using the chemical injection apparatus 10. FIG. Here, the chemical injection position of the corrosion inhibitor composed of morpholine fatty acid salt in the steam pipe 3 is preferably the upstream side of the steam pipe 3, and the corrosion inhibitor composed of morpholine fatty acid salt is more preferably supplied to the upstream position. Corrosion of the steam pipe 3 and the condensate pipe 5 as a whole can be suppressed.
[0025]
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 2 is an explanatory diagram schematically showing the configuration of the second embodiment of the present invention, in which a steam header 11 is provided in the steam pipe 3 of the first embodiment. When the steam header 11 is provided, the corrosion inhibitor made of morpholine fatty acid salt is poured into the steam header 11 by using the chemical injection device 10. When the steam is distributed and supplied to a plurality of load devices 2, 2,..., The chemical injection device 10 is provided in each of the steam pipes 3, 3,. It is not necessary, and the number of installed chemical injection devices 10 can be reduced.
[0026]
Moreover, when it is necessary to change the corrosion inhibitor which consists of a morpholine fatty acid salt according to the use of each said load equipment 2 side, it supplies to each said load equipment 2 from the said steam header 11 according to the use. The chemical injection device 10 may be provided in each of the steam pipes 3.
[0027]
Next, a case where a corrosion inhibitor composed of a morpholine fatty acid salt is poured into the condensate pipe 5 will be described. The condensate pipe 5 is provided with the steam trap 9. Water and steam are separated by the steam trap 9 and only water is discharged. Therefore, it exists as condensate on the downstream side of the steam trap 9. In FIG. 1 of the first embodiment, it is preferable to pour medicine into a position immediately after the steam trap 9. That is, in FIG. 1, the chemical injection device 10 is provided as shown by a one-dot chain line. In FIG. 2 of the second embodiment, it is preferable to inject medicine to a position immediately after each steam trap 9. That is, in FIG. 2, as shown by the alternate long and short dash line, each of the drug injection devices 10 is provided. By providing the chemical injection device 10 on the downstream side of the steam trap 9, all of the corrosion inhibitors made of morpholine fatty acid salts can be used as corrosion inhibitors.
[0028]
The case where the medicine is poured into the steam pipe 3 or both the steam header 11 and the condensate pipe 5 will be described. In FIG. 1 of the first embodiment, the position on the upstream side of the steam pipe 3 (in FIG. 2, in the steam pipe 3 after the steam header 11, the position immediately after exiting the steam header 11) It is preferable to inject medicine into both the position immediately after the steam trap 9. That is, in FIG. 1, as shown by the solid line and the alternate long and short dash line, the drug injection device 10 is provided in both. In FIG. 2 of the second embodiment, it is preferable to pour both the steam header 11 and the position immediately after the steam trap 9. That is, in FIG. 2, as shown by the solid line and the alternate long and short dash line, the drug injection device 10 is provided. By providing the chemical injection device 10 to both the steam pipe 3 and the condensate pipe 5, the consumption of the corrosion inhibitor made of morpholine fatty acid salt consumed in the steam pipe 3 is divided into the condensate pipe 5. By pouring into the pipe, corrosion of the condensate pipe 5 can be more effectively suppressed.
[0029]
Hereinafter, specific experimental examples of the present invention will be described. First, a method for adjusting the corrosion inhibitor used in the specific experimental examples will be described.
[0030]
Corrosion inhibitor 1
Morpholine oleate as a morpholine fatty acid salt was dissolved in water to obtain 5% by weight of emulsion A.
[0031]
Corrosion inhibitor 2
Morpholine laurate as a morpholine fatty acid salt was dissolved in water to obtain 3% by weight of emulsion B.
[0032]
Corrosion inhibitor 3
Morpholine stearate as a morpholine fatty acid salt was dissolved in water to obtain 3% by weight of emulsion C.
[0033]
First experiment example
Soft water is supplied to a small once-through boiler with an evaporation rate of 500 kg / h, and the pressure is 8 kg / cm.²The operation was performed while continuously generating steam. Then, 300 mg / liter (per liter of feed water) of the emulsion A as a corrosion inhibitor composed of a morpholine fatty acid salt was poured into the steam pipe (300 mg of the emulsion A was poured into the steam pipe with respect to 1 liter of feed water). At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0034]
Second experiment example
Soft water is supplied to a small once-through boiler with an evaporation rate of 500 kg / h, and the pressure is 8 kg / cm.²The operation was performed while continuously generating steam. Then, 500 mg / liter of emulsion B was poured into the steam pipe as a corrosion inhibitor composed of a morpholine fatty acid salt (per 1 liter of feed water) (500 mg of emulsion B was poured into the steam pipe with respect to 1 liter of feed water). At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0035]
Third experimental example
Soft water is supplied to a small once-through boiler with an evaporation rate of 500 kg / h, and the pressure is 8 kg / cm.²The operation was performed while continuously generating steam. Then, 500 mg / liter (per liter of feed water) of the emulsion C as a corrosion inhibitor composed of morpholine fatty acid salt was poured into the steam pipe (500 mg of the emulsion C was poured into the steam pipe for 1 liter of feed water). At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0036]
Fourth experimental example
Soft water is supplied to a small once-through boiler with an evaporation rate of 500 kg / h, and the pressure is 8 kg / cm.²The operation was performed while continuously generating steam. Then, 300 mg / liter (per liter of feed water) of the emulsion A was poured into the steam header as a corrosion inhibitor made of morpholine fatty acid salt (300 mg of the emulsion A was poured into the steam header with respect to 1 liter of feed water). At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0037]
Fifth experiment example
Soft water is supplied to a small once-through boiler with an evaporation rate of 500 kg / h, and the pressure is 8 kg / cm.²The operation was performed while continuously generating steam. Then, 500 mg / liter of emulsion B was poured into the steam header (per liter of feed water) as a corrosion inhibitor composed of a morpholine fatty acid salt (500 mg of emulsion B was poured into the steam header with respect to 1 liter of feed water). At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0038]
Sixth experiment example
Soft water is supplied to a small once-through boiler with an evaporation rate of 500 kg / h, and the pressure is 8 kg / cm.²The operation was performed while continuously generating steam. Then, 500 mg / liter of emulsion C as a corrosion inhibitor composed of morpholine fatty acid salt was poured into the steam header (per liter of feed water) (500 mg of emulsion C was poured into the steam header for 1 liter of feed water). At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0039]
Seventh experimental example
Soft water is supplied to a small once-through boiler with an evaporation rate of 500 kg / h, and the pressure is 8 kg / cm.²The operation was performed while continuously generating steam. Then, 300 mg / liter (per liter of feed water) of Emulsion A as a corrosion inhibitor made of morpholine fatty acid salt was poured into the condensate pipe (300 mg of Emulsion A was poured into the condensate pipe for 1 liter of feed water. ). At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0040]
Eighth experimental example
Soft water is supplied to a small once-through boiler with an evaporation rate of 500 kg / h, and the pressure is 8 kg / cm.²The operation was performed while continuously generating steam. Then, 500 mg / liter of emulsion B was poured into the condensate pipe as a corrosion inhibitor made of morpholine fatty acid salt (per liter of feed water) (500 mg of emulsion B was poured into the condensate pipe for 1 liter of feed water. ). At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0041]
Ninth experiment example
Soft water is supplied to a small once-through boiler with an evaporation rate of 500 kg / h, and the pressure is 8 kg / cm.²The operation was performed while continuously generating steam. Then, 500 mg / liter of emulsion C as a corrosion inhibitor composed of morpholine fatty acid salt was poured into the condensate pipe (per liter of feed water) (500 mg of emulsion C was poured into the condensate pipe with respect to 1 liter of feed water. ). At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0042]
First comparative example
As a corrosion inhibitor composed of morpholine fatty acid salt, emulsified liquid A was fed into a small once-through boiler with an evaporation amount of 500 kg / h, 300 mg / liter (per liter of feed water) of soft water, and a pressure of 8 kg / cm.²The operation was performed while continuously generating steam. At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0043]
Second comparative example
As a corrosion inhibitor composed of morpholine fatty acid salt, emulsified liquid B is fed into a small once-through boiler with an evaporation amount of 500 kg / h, 500 mg / liter (per liter of feed water) of soft water, and a pressure of 8 kg / cm.²The operation was performed while continuously generating steam. At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0044]
Third comparative example
Emulsion C as a corrosion inhibitor composed of a morpholine fatty acid salt is supplied to a small once-through boiler with an evaporation amount of 500 kg / h, 500 mg / liter (per liter of feed water) of soft water poured into the water, and a pressure of 8 kg / cm.²The operation was performed while continuously generating steam. At this time, a test piece (mild steel 50 mm × 25 mm × 1 mm) was immersed in the condensate, and the corrosion rate (mdd) for 48 hours was measured. The results are shown in Table 1. Here, the water used for the water supply was softened from tap water in Matsuyama City, Ehime Prefecture. The water quality is pH: 8.1, electric conductivity: 250 μS / cm, M alkalinity: 50 mg CaCO._Three/ Liter.
[0045]
[Table 1]

[0046]
As is apparent from Table 1, the corrosion rate of the morpholine fatty acid salt salt injection to the water supply is greater than the rate of the chemical injection to the steam pipe, steam header and condensate pipe, and the corrosion inhibition effect is low. I understand. In general, a corrosion inhibitor composed of a morpholine fatty acid salt is distributed between steam and boiler water in a boiler. Therefore, the amount of the corrosion inhibitor composed of a morpholine fatty acid salt exhibiting a corrosion inhibitory effect in the steam pipe and the condensate pipe is reduced from the time of chemical injection. Thereby, the corrosion inhibition effect is weakened and the corrosion rate is increased. In other words, when a corrosion inhibitor made of morpholine fatty acid salt is poured into the steam pipe, steam header and condensate pipe, the same corrosion inhibitory effect is obtained with a smaller amount of injection than a corrosion inhibitor made of morpholine fatty acid salt that is poured into the water supply. Obtainable. In addition, since the fatty acid portion of the corrosion inhibitor made of morpholine fatty acid salt acts as a film-type anticorrosive agent, a chemical injection of the corrosion inhibitor made of morpholine fatty acid salt into the steam pipe, steam header and condensate pipe can be used as a boiler. It is possible to eliminate the possibility of causing trouble in water level control by forming a film on the inner water level electrode. Furthermore, when the medicine is poured into the steam header as in the second embodiment, it is only necessary to provide one medicine injection device, so the number of medicine injection devices can be reduced.
[0047]
【The invention's effect】
As described above, according to the present invention, the corrosion inhibitor made of morpholine fatty acid salt necessary for corrosion prevention of steam pipes and condensate pipes can be poured without waste, and troubles in water level control can be prevented. Can do.
[Brief description of the drawings]
FIG. 1 is an explanatory view schematically showing a first embodiment of the present invention.
FIG. 2 is an explanatory view schematically showing a second embodiment of the present invention.
FIG. 3 is an explanatory view schematically showing a conventional drug injection method.
[Explanation of symbols]
        1 boiler
        2 Loaded equipment
        3 Steam piping
        5 Condensate piping
        9 Steam trap
      11 Steam header

Claims (2)

A boiler 1 that generates steam by heating feed water, a load device 2 that uses steam, a steam pipe 3 for supplying steam to the load device 2, and steam used in the load device 2 are condensed. In the boiler equipment provided with the condensate pipe 5 for collecting the condensate obtained in this way and mixing it with the feed water, the position on the most upstream side of the steam pipe 3 and the steam trap 9 provided in the condensate pipe 5 A corrosion inhibitor made of a morpholine fatty acid salt is poured into one or both of the condensate pipe 5 and the position adjacent to the steam trap 9 on the downstream side of the condensate . A boiler 1 that generates steam by heating feed water, a load device 2 that uses steam, a steam pipe 3 for supplying steam to the load device 2, and a steam header 11 provided in the steam pipe 3 In the boiler equipment provided with the condensate pipe 5 for collecting the condensate obtained by condensing the steam used in the load device 2 and mixing it with the feed water, the steam header 11 and the condensate pipe A corrosion inhibitor composed of a morpholine fatty acid salt is poured into one or both of the condensate pipe 5 and a position adjacent to the steam trap 9 on the downstream side of the steam trap 9 provided in FIG. A method for injecting corrosion inhibitors.

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