JP2007260540A - Defoaming agent and defoaming method of water system water - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a defoaming agent for eliminating the need of using a silicone based defoaming agent component or using a small amount of it and obtaining a high defoaming effect even under the presence of a highly foamable chemical such as quaternary ammonium salt. <P>SOLUTION: The defoaming agent comprises the silicone based defoaming component and/or a polyether based defoaming agent component and an aliphatic alkoxylate based defoaming component. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a water-based antifoaming agent, and more particularly to an antifoaming agent used in an open circulation cooling water system for air conditioning, various industrial use, and the like.

  In water systems such as cooling water systems and wastewater treatment, foaming may occur due to the growth of microorganisms or the use of chemicals, which may cause troubles such as foam scattering and poor chemical injection due to pumping.

  In addition, the present inventors have proposed quaternary ammonium salts (Patent Document 1), quaternary phosphonium salts (Patent Document 2) and the like as slime control agents that suppress the growth of microorganisms. Although these are excellent chemicals having extremely high slime control properties, application to an open circulating cooling water system is difficult due to severe foaming.

  Here, as a typical antifoaming agent that has been conventionally used in aqueous systems, silicone antifoaming agents can be mentioned. These are highly soluble (dispersed in water), although high effects can be obtained with a small amount of addition. Therefore, these defoaming agent components can entrap dirt such as earth and sand and adhere to equipment and pipes in the system due to excessive use and long-term use, particularly deteriorating the beauty of the cooling tower and its surroundings. In addition, an accident such as a decrease in heat exchange efficiency may occur.

In addition to silicone-based antifoaming agents, polyether-based antifoaming agents and alcohol-based surfactants have also been used (Patent Document 3), but these cannot be fully effective with a small amount of addition. There were drawbacks.
JP-A-11-156366 JP 2002-308713 A JP-A-9-308804

  The present invention improves the above-mentioned conventional problems, that is, even in the presence of a highly foaming chemical such as a quaternary ammonium salt, the use of a silicone-based antifoaming agent is unnecessary or a small amount is sufficient. In addition, an object is to provide an antifoaming agent capable of obtaining a high defoaming effect.

  In order to solve the above problems, the antifoaming agent of the present invention has a silicone-based antifoaming agent component and / or a polyether-based antifoaming agent component and an aliphatic alkoxylate-based antifoaming agent as described in claim 1. An antifoaming agent characterized by comprising the components.

  Moreover, the defoaming method of the aqueous water according to the present invention includes a silicone-based antifoaming agent and / or a polyether-based antifoaming agent and an aliphatic alkoxylate-based antifoaming agent as described in claim 2. Is a method for defoaming water based on water.

  According to the antifoaming agent of the present invention, a high defoaming effect can be obtained with a small amount of addition, so that the cost can be reduced, and the silicone antifoaming agent that adheres to an aqueous device and causes dirt and various problems. The use of can be greatly reduced. In particular, it is particularly effective if it is used together with the addition of another drug having high foaming properties to aqueous water.

  The antifoaming agent of the present invention comprises a silicone antifoam component and / or a polyether antifoam component and an aliphatic alkoxylate antifoam component.

  The silicone-based antifoam component and the aliphatic alkoxylate-based defoamer component can be used in an appropriate blending ratio, but are usually blended so that the weight ratio of the active ingredient is 1: 1000 to 1: 2. However, it is preferable because a high effect (synergistic effect by these two components) can be obtained with a small amount of addition. A more preferable blending ratio is 1: 200 to 1:10.

  Also, a combination of a polyether antifoam component and an aliphatic alkoxylate defoamer component can be used in an appropriate blending ratio, but usually in an active ingredient weight ratio of 1:50 to 50: It is preferable to add 1 so that a high effect (synergistic effect by these two kinds of components) can be obtained with a small amount of addition. A more preferable blending ratio is 1:10 to 10: 1.

  In the present invention, the above three components, the silicone-based antifoam component, the polyether-based antifoam component and the aliphatic alkoxylate-based antifoam component, can be simultaneously added to aqueous water. A sufficiently high effect can be obtained by the combination.

  With regard to the amount added to the aqueous system, in the combination of the aliphatic alkoxylate-based antifoaming agent and the silicone-based antifoaming agent, the active ingredient is from 0.1 mg / L to 100 mg / L with respect to the aqueous water. It is preferable to add, and a more preferable range is 0.5 mg / L or more and 20 mg / L or less. If the addition is less than 0.1 mg / L, a sufficient effect may not be obtained, and even if it is added so as to have a high concentration of 100 mg / L or more, an increase in effect commensurate with the increase in the addition amount cannot be obtained. Absent.

  On the other hand, in the combination of the aliphatic alkoxylate antifoaming agent and the polyether antifoaming agent, the amount added to the aqueous system is such that the active ingredient is 0.1 mg / L or more and 100 mg / L or less with respect to the aqueous water. It is preferable to add to, and a more preferable range is 1 mg / L or more and 40 mg / L or less. Here, if the addition is less than 0.1 mg / L, a sufficient effect may not be obtained, and even if it is added so as to have a high concentration of 100 mg / L or more, an increase in effect commensurate with the increase in the addition amount. Cannot be obtained.

  The antifoaming agent of the present invention can be used in combination with other chemicals, slime control agents, amoebicidal agents, bactericides, anticorrosives, rust inhibitors and the like as long as the effect is not impaired.

Examples of the antifoaming agent of the present invention will be described below.
A quaternary ammonium chemical (benzalkonium chloride) was added to 50 mL of Tsukuba city water so that the active ingredient concentration would be 20 mg / L to obtain a foamable sample.

  To such foamable samples, the antifoam components shown in Table 1 were added in the addition amounts shown in Table 2, respectively, placed in a 100 mL screw cap bottle, shaken for 1 minute, and the foaming state was visually observed. confirmed. The results are also shown in Table 2.

  According to Table 2, according to the present invention, the silicone-based antifoaming agent component is unnecessary, the amount of use can be reduced to a very small level, and the amount of addition as an antifoaming agent is small and high foaming prevention It can be seen that it exhibits sex. In particular, it was confirmed that even when used in combination with a highly foamable cationic slime control agent, an excellent effect of exhibiting a sufficient foaming suppression effect with a small amount of addition was confirmed.

  The present invention makes it unnecessary to use a silicone-based antifoaming agent even in the presence of a highly foaming chemical such as a quaternary ammonium salt, and a sufficient amount of antifoaming effect can be obtained by adding a small amount. The resulting antifoaming agent can be suitably used particularly in an open circulation cooling water system.

Claims (2)

  An antifoaming agent comprising a silicone antifoam component and / or a polyether antifoam component and an aliphatic alkoxylate antifoam component.   A defoaming method for aqueous water, comprising adding a silicone-based antifoam component and / or a polyether-based antifoam component and an aliphatic alkoxylate-based antifoam component to aqueous water.