JP4689802B2 - Dispersant for ice water slurry - Google Patents

Description

〔式中、Ｒ¹は炭素数１４〜２２のアルキル基又はアルケニル基、Ｒ²、Ｒ³は炭素数１〜５のアルキル基又は（ＡＯ）_nＨ基（但し、ＡＯは炭素数２〜４のオキシアルキレン基を示し、ｎは１〜５の実数である。）を示す。〕
【００１０】
以下、本発明について更に詳しく説明すると、本発明の氷水スラリー用分散剤は、下記（Ａ）の界面活性剤を含み、必要に応じてさらに（Ｂ）〜（Ｄ）から選ばれる少なくとも１種の界面活性剤を含むものである。
【００１１】
（Ａ）下記一般式（１）で示されるアミノ酢酸型ベタイン系界面活性剤
【化７】

【００１２】
式（１）中、Ｒ¹は炭素数８〜２２、好ましくは１４〜２０のアルキル基又はアルケニル基である。なお、Ｒ¹は植物性及び動物性の天然脂肪酸残基である混合アルキル基、混合アルケニル基であっても構わない。
【００１３】
Ｒ²，Ｒ³は炭素数１〜５のアルキル基又は（ＡＯ）_nＨ基（但し、ＡＯは炭素数２〜４のオキシアルキレン基を示し、ｎは１〜５の実数である。）を示し、好ましくはメチル基、エチル基、ヒドロキシエチル基である。
【００１４】
このような（Ａ）のアミノ酢酸型ベタイン系界面活性剤としては、具体的には、オクチルジメチルアミノ酢酸ベタイン、ドデシルジメチルアミノ酢酸ベタイン、ミリスチルジメチルアミノ酢酸ベタイン、パルミチルジメチルアミノ酢酸ベタイン、ステアリルジメチルアミノ酢酸ベタイン、オレイルジメチルアミノ酢酸ベタイン、ヤシアルキルジメチルアミノ酢酸ベタイン、牛脂アルキルジメチルアミノ酢酸ベタイン、ミリスチルジヒドロキシエチルアミノ酢酸ベタイン、パルミチルジヒドロキシエチルアミノ酢酸ベタイン、ステアリルジヒドロキシエチルアミノ酢酸ベタイン、オレイルジヒドロキシエチルアミノ酢酸べタインなどが挙げられ、これらの１種を単独で又は２種以上を組合せて用いることができる。これらの中でも、ミリスチルジメチルアミノ酢酸ベタイン、パルミチルジメチルアミノ酢酸ベタイン、ステアリルジメチルアミノ酢酸ベタイン、オレイルジメチルアミノ酢酸ベタインが好ましい。
【００１５】
（Ｂ）オレイン酸塩を主成分とする界面活性剤
このオレイン酸塩を主成分とする界面活性剤としては、オレイン酸のＮａ，Ｋ等のアルカリ金属塩、Ｍｇ，Ｃａ等のアルカリ土類金属塩、アミン塩、アンモニウム塩等のオレイン酸塩；オレイン酸を主成分とする植物性及び動物性の天然脂肪酸（例えば牛脂脂肪酸、パーム油脂肪酸等）のアルカリ金属塩、アルカリ土類金属塩、アミン塩、アンモニウム塩などが挙げられ、これらの中でも、オレイン酸Ｎａ、牛脂脂肪酸Ｎａが好ましい。
【００１６】
（Ｃ）下記一般式（２）で示される脂肪族アミンのポリアルコキシレート
【化８】

【００１７】
式（２）中、Ｒ⁴は炭素数８〜２２、好ましくは１２〜２０のアルキル基又はアルケニル基である。なお、Ｒ⁴は植物性及び動物性の天然脂肪酸残基である混合アルキル基、混合アルケニル基であっても構わない。
【００１８】
また、ＡＯは炭素数２〜４のオキシアルキレン基、好ましくはオキシエチレン基を示し、ｐ，ｑはｐ≧１、ｑ≧１、ｐ＋ｑ＝２〜１００、好ましくは２〜５０を満たす実数である。
【００１９】
このような（Ｃ）の脂肪族アミンのポリアルコキシレートとしては、具体的には、ポリオキシエチレンオクチルアミン、ポリオキシエチレンドデシルアミン、ポリオキシエチレンパルミチルアミン、ポリオキシエチレンステアリルアミン、ポリオキシエチレンオレイルアミン、ポリオキシエチレンヤシアミン、ポリオキシエチレン牛脂アミン、ポリオキシエチレン硬化牛脂アミンなどが挙げられ、これらの１種を単独で又は２種以上を組合せて用いることができる。中でも、ポリオキシエチレンオレイルアミン、ポリオキシエチレンヤシアミン、ポリオキシエチレン牛脂アミン、ポリオキシエチレン硬化牛脂アミンが好ましい。
【００２０】
（Ｄ）下記一般式（３）で示される脂肪族アミドのポリアルコキシレート
【化９】

【００２１】
式（３）中、Ｒ⁵は炭素数７〜２１、好ましくは１１〜１９のアルキル基又はアルケニル基である。なお、Ｒ⁵は植物性及び動物性の天然脂肪酸残基である混合アルキル基、混合アルケニル基であっても構わない。
【００２２】
また、ＡＯは炭素数２〜４のオキシアルキレン基、好ましくはオキシエチレン基を示し、ｐ，ｑはｐ≧１、ｑ≧１、ｐ＋ｑ＝２〜１００、好ましくは２〜５０である。
【００２３】
このような（Ｄ）の脂肪族アミドのポリアルコキシレートとしては、具体的には、ポリオキシエチレンオクチルアミド、ポリオキシエチレンドデシルアミド、ポリオキシエチレンパルミチルアミド、ポリオキシエチレンステアリルアミド、ポリオキシエチレンオレイルアミド、ポリオキシエチレンヤシアミド、ポリオキシエチレン牛脂アミド、ポリオキシエチレン硬化牛脂アミドなどが挙げられ、これらの１種を単独で又は２種以上を組合せて用いることができる。中でも、ポリオキシエチレンオレイルアミド、ポリオキシエチレンヤシアミド、ポリオキシエチレン牛脂アミド、ポリオキシエチレン硬化牛脂アミドが好ましい。
【００２４】
上記（Ａ）〜（Ｄ）の界面活性剤は、いずれも本発明の氷水スラリー用分散剤として極めて有効なものであるが、本発明においてはこれら界面活性剤を２種以上組合わせたものも氷水スラリー用分散剤として好適に用いることができる。この場合特に、（Ａ）の界面活性剤と（Ｂ）の界面活性剤とを組合せたもの、（Ａ）の界面活性剤と（Ｄ）の界面活性剤とを組合せたものなどが著効を示し、好ましい。
【００２５】
また、（Ａ）の界面活性剤と、下記（Ｅ）の脂肪族第４級アンモニウム塩或いは（Ｂ）の界面活性剤とを併用すると、優れた安定かつ微細な氷結晶粒子水スラリーを生成することができると共に、ＤＲ効果も期待できるので一層好ましい。
【００２６】
（Ｅ）下記一般式（４）で示される脂肪族第４級アンモニウム塩
【化１０】

〔式中、Ｒ⁶は炭素数８〜２２のアルキル基又はアルケニル基、Ｒ⁷、Ｒ⁸、Ｒ⁹はいずれも炭素数１〜５のアルキル基又は（ＡＯ）_sＨ基（但し、ＡＯは炭素数２〜４のオキシアルキレン基を示し、ｓは１〜５の実数である）であって、Ｒ⁷、Ｒ⁸、Ｒ⁹のうちの少なくとも一つは（ＡＯ）_sＨ基である。Ｘ^-は対アニオンを示す。〕
【００２７】
式（４）中、Ｒ⁶は炭素数８〜２２、好ましくは１２〜２０のアルキル基又はアルケニル基である。なお、Ｒ⁶は植物性及び動物性の天然脂肪酸残基である混合アルキル基、混合アルケニル基であっても構わない。
【００２８】
また、ＡＯは炭素数２〜４のオキシアルキレン基、好ましくはオキシエチレン基を示し、ｓは１〜５、好ましくは１〜２である。
【００２９】
Ｘ^-は、無機又は有機アニオンを示し、例えばハロゲンイオン、酢酸アニオン残基、メトサルフェートアニオンなどである。
【００３０】
このような（Ｅ）の脂肪族第４級アンモニウム塩としては、具体的には、オクチルジメチルモノ（ヒドロキシエチル）アンモニウムクロライド、ドデシルジメチルモノ（ヒドロキシエチル）アンモニウムクロライド、ステアリルジメチルモノ（ヒドロキシエチル）アンモニウムクロライド、オレイルジメチルモノ（ヒドロキシエチル）アンモニウムクロライド、オクチルメチルジ（ヒドロキシエチル）アンモニウムクロライド、ドデシルメチルジ（ヒドロキシエチル）アンモニウムクロライド、ステアリルメチルジ（ヒドロキシエチル）アンモニウムクロライド、オレイルメチルジ（ヒドロキシエチル）アンモニウムクロライド、牛脂メチルジ（ヒドロキシエチル）アンモニウムクロライド、ステアリルトリ（ヒドロキシエチル）アンモニウムクロライド、オレイルトリ（ヒドロキシエチル）アンモニウムクロライドなどが挙げられ、これらの１種を単独で又は２種以上を組合せて用いることができる。中でも、ステアリルメチルジ（ヒドロキシエチル）アンモニウムクロライド、オレイルメチルジ（ヒドロキシエチル）アンモニウムクロライド、オレイルトリ（ヒドロキシエチル）アンモニウムクロライドが好ましい。
【００３１】
この場合、（Ａ）の界面活性剤と他の界面活性剤（例えば（Ｂ）の界面活性剤、（Ｅ）の界面活性剤など）との配合比率は、質量比で、（Ａ）の界面活性剤：他の界面活性剤＝１：９〜９：１、好ましくは３：７〜７：３である。
【００３２】
なお、本発明においては、従来技術で述べた公知のソルビタン系界面活性剤であるｔｗｅｅｎ８０を（Ｅ）の脂肪族第４級アンモニウム塩と併用したものも氷水スラリー用分散剤として優れた性能を有するものである。
【００３３】
本発明の氷水スラリー用分散剤である（Ａ）〜（Ｄ）の界面活性剤は、氷水スラリー全体に対して合計量で好ましくは０．００１〜５質量％、より好ましくは０．００３〜０．３質量％配合することが好ましい。界面活性剤が少なすぎるとは安定かつ微細な氷を生成できなくなる場合がある。一方、多すぎると氷水に不溶性となったり、発泡して好ましくない場合がある。
【００３４】
次に、本発明の氷水スラリー用分散剤の使用方法は、所定の濃度の本発明の界面活性剤水溶液を調製し、これを徐々に水の氷点以下に冷却する。この際、無攪拌でもよいが、ゆるやかに攪拌しつつ冷却することが好ましい。このように冷却していくと、全体が細かな０．０１ｍｍ〜数ｍｍの微細な氷の結晶が生成してくる。これに対し、本発明の界面活性剤を添加しない場合は、結晶粒子が巨大化してくると共に、容器及び配管の壁面にはりついて氷の結晶が成長するという不都合が生じるが、本発明の界面活性剤水溶液は、このような不都合が生じることがない。
【００３５】
このようにして、氷の含有率（ＩＰＦ；氷固体質量割合）が５〜５０質量％、好ましくは１０〜４０質量％の０．０１ｍｍ〜数ｍｍの微細結晶の氷を安定に保持した氷水スラリーを得ることができる。
【００３６】
本発明の氷水スラリー用分散剤によれば、微細な結晶の氷からなる氷水スラリーを調製することができ、潜熱輸送空調システムに適用して氷水スラリーを直接輸送する場合において、配管等での詰まりを起こして、輸送不能になることがなく、また、微小の氷の結晶であるため、伝熱効率にも優れているものである。
【００３７】
【発明の効果】
本発明によれば、安定かつ微細な氷結晶粒子スラリーを生成することができると共に、ＤＲ効果をも有する極めて効率が良く、より低温まで冷却可能な潜熱輸送を応用した空調システムを得ることができる。
【００３８】
【実施例】
以下、実施例と比較例とを示して本発明を具体的に説明するが、本発明は下記実施例に限定されるものではない。
【００３９】
〔実施例１、比較例１〕 氷水スラリーの氷性状の評価
１リットルビーカーに、表１に示した各種界面活性剤を１０００ｐｐｍ溶解させた水５００ｍＬを添加し、クールスターラー上でゆるく攪拌下、氷点まで冷却し、生成する氷の性状を目視及び手で攪拌して下記評価基準で判定した。結果を表１に示す。なお、比較として界面活性剤を無添加の場合についても同様に判定した。
【００４０】
<評価基準>
◎：氷のビーカー壁面への付着が全くなく、氷の結晶同士の融合も全くなく、微細な氷が均一に分散している。
○：氷のビーカー壁面への付着が殆どなく、氷の結晶同士の融合も殆どなく、微細な氷がほぼ均一に分散している。
△：氷のビーカー壁面への付着と氷の結晶同士の融合が少し見られる。
×：氷のビーカー壁面への付着が著しく、氷の結晶同士が融合して氷の結晶が大きく成長している。
【００４１】
【表１】

【００４２】
〔実施例２〕 ＤＲ効果の評価
氷水スラリーの氷の性状評価に用いた界面活性剤水溶液の中、表１の試料Ｎｏ．１３，１５，１６について、室温での見かけ粘度を、回転円筒粘度計（Ｒｈｅｏｍｅｔｒｉｃ Ｓｃｉｅｎｔｉｆｉｃ社製 ＳＲ−５型）を用いて測定したところ、いずれの試料も粘度上昇が認められた。
【００４３】
このように粘度上昇の認められる場合には、棒状ミセルの存在が予想され、これら界面活性剤にはＤＲ効果が期待できるものである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a dispersant for ice water slurry that can generate a stable and fine ice crystal particle water slurry, and more particularly, to a dispersant for ice water slurry that can be suitably used in an air conditioning system to which latent heat transport is applied.
[0002]
[Prior art and problems to be solved by the invention]
In recent years, an ice storage air conditioning system called eco ice has been developed. This system manufactures ice using cheap nighttime electricity, stores it, and circulates cold water that melts this ice in the daytime for air conditioning, but the amount of heat transported by circulation However, there was a drawback that only the sensible heat of water and the amount of water to be transported increased.
[0003]
Therefore, as a more efficient means, a method is being considered in which fine ice crystals are generated using an additive, and an ice water slurry in which the ice crystals are stably dispersed is prepared and directly transported. According to this method, since the latent heat of ice water can be directly transported, it can be cooled to a lower temperature than that of cold water transport, and a more efficient latent heat transport air conditioning system is expected to be obtained.
[0004]
However, there are still very few reports on additives effective in this method. For example, silane coupling agents [Saito et al., Transactions of the Japan Society of Mechanical Engineers (B), 65,463 (1999)], sorbitan-based surface activity Agent [Akutani et al., Abstracts of Chemical Engineering Society of Japan, 496 (1998)], anti-frozen protein [Grandum et al. Thermophysics and Heat Transfer, 11, 461 (1997)] and the like have been proposed only slightly, and no additive having sufficient performance has been developed yet.
[0005]
On the other hand, additives that can bring about a reduction in energy required for pumping during heat transport using water are also being investigated, and by adding a special surfactant to water to form rod-like micelles, Methods have been proposed that can lead to a reduction in the energy requirements of the pump when transporting water.
[0006]
However, the additive used in the above method has a piping frictional resistance reduction effect (hereinafter abbreviated as DR effect) that brings about an effect of lowering the required energy of the pump, but is stable and fine required for ice water slurry. It is difficult to prepare an ice crystal particle slurry, and sufficient effects have not been achieved.
[0007]
The present invention has been made in view of the above circumstances, and is capable of generating a stable and fine ice crystal particle water slurry, and also has a DR effect, and is very efficient and latent heat transport that can be cooled to a lower temperature. It aims at providing the dispersing agent for ice water slurries which can obtain an air-conditioning system.
[0008]
Means for Solving the Problem and Embodiment of the Invention
As a result of intensive studies to achieve the above object, the present inventor has found that a dispersant for an ice water slurry containing an aminoacetic acid type betaine surfactant represented by the following general formula (1) is stable and fine ice crystals. It has been found that a particle water slurry can be generated and also has a DR effect, and it is possible to achieve a latent heat transport air-conditioning system that is extremely efficient and can be cooled to a lower temperature.
[0009]
(A) Aminoacetic acid type betaine surfactant represented by the following general formula (1)

[Wherein, R ¹ is an alkyl or alkenyl group having 14 to 22 carbon atoms, R ² and R ³ are alkyl groups having 1 to 5 carbon atoms or (AO) _n H group (where AO is 2 to 4 carbon atoms) And n is a real number of 1 to 5.) ]
[0010]
Hereinafter, the present invention will be described in more detail. The dispersant for ice water slurry of the present invention contains the following surfactant (A) , and further contains at least one selected from (B) to (D) as necessary . A surfactant is included.
[0011]
(A) Aminoacetic acid-type betaine surfactant represented by the following general formula (1)

[0012]
In the formula (1), R ¹ is an alkyl group or alkenyl group having 8 to 22 carbon atoms, preferably 14 to 20 carbon atoms. R ¹ may be a mixed alkyl group or mixed alkenyl group that is a vegetable or animal natural fatty acid residue.
[0013]
R ² and R ³ are each an alkyl group having 1 to 5 carbon atoms or an (AO) _n H group (where AO represents an oxyalkylene group having 2 to 4 carbon atoms, and n is a real number having 1 to 5). Preferably a methyl group, an ethyl group, or a hydroxyethyl group.
[0014]
Specific examples of (A) aminoacetic acid type betaine surfactants include octyldimethylaminoacetic acid betaine, dodecyldimethylaminoacetic acid betaine, myristyldimethylaminoacetic acid betaine, palmityldimethylaminoacetic acid betaine, stearyldimethyl. Betaine aminoacetate, oleyldimethylaminoacetic acid betaine, palm alkyldimethylaminoacetic acid betaine, beef tallow alkyldimethylaminoacetic acid betaine, myristyldihydroxyethylaminoacetic acid betaine, palmityldihydroxyethylaminoacetic acid betaine, stearyldihydroxyethylaminoacetic acid betaine, oleyldihydroxyethylamino Examples include betaine acetate and the like, and one of these can be used alone or in combination of two or more. Among these, myristyldimethylaminoacetic acid betaine, palmityldimethylaminoacetic acid betaine, stearyldimethylaminoacetic acid betaine, and oleyldimethylaminoacetic acid betaine are preferable.
[0015]
(B) Surfactant mainly composed of oleate As the surfactant mainly composed of oleate, alkali metal salts such as Na and K of oleic acid and alkaline earth metals such as Mg and Ca Oleates such as salts, amine salts, ammonium salts; alkali metal salts, alkaline earth metal salts, amines of plant and animal natural fatty acids (eg beef tallow fatty acid, palm oil fatty acid, etc.) based on oleic acid Examples thereof include salts and ammonium salts, and among these, oleic acid Na and beef tallow fatty acid Na are preferable.
[0016]
(C) Polyalkoxylate of an aliphatic amine represented by the following general formula (2)

[0017]
In the formula (2), R ⁴ is an alkyl group or alkenyl group having 8 to 22 carbon atoms, preferably 12 to 20 carbon atoms. R ⁴ may be a mixed alkyl group or mixed alkenyl group that is a vegetable or animal natural fatty acid residue.
[0018]
AO represents an oxyalkylene group having 2 to 4 carbon atoms, preferably an oxyethylene group, and p and q are real numbers satisfying p ≧ 1, q ≧ 1, p + q = 2 to 100, preferably 2 to 50. .
[0019]
Specific examples of the aliphatic alkoxy polyalkoxylate (C) include polyoxyethylene octylamine, polyoxyethylene dodecylamine, polyoxyethylene palmitylamine, polyoxyethylene stearylamine, and polyoxyethylene. Examples include oleylamine, polyoxyethylene coconut amine, polyoxyethylene beef tallow amine, polyoxyethylene beef tallow amine, and the like. These can be used alone or in combination of two or more. Among these, polyoxyethylene oleylamine, polyoxyethylene coconut amine, polyoxyethylene beef tallow amine, and polyoxyethylene hardened tallow amine are preferable.
[0020]
(D) Polyalkoxylate of aliphatic amide represented by the following general formula (3)

[0021]
In Formula (3), R ⁵ is an alkyl group or alkenyl group having 7 to 21 carbon atoms, preferably 11 to 19 carbon atoms. R ⁵ may be a mixed alkyl group or mixed alkenyl group that is a vegetable or animal natural fatty acid residue.
[0022]
AO represents an oxyalkylene group having 2 to 4 carbon atoms, preferably an oxyethylene group, and p and q are p ≧ 1, q ≧ 1, p + q = 2 to 100, preferably 2 to 50.
[0023]
Specific examples of the polyalkoxylate of the aliphatic amide (D) include polyoxyethylene octyl amide, polyoxyethylene dodecyl amide, polyoxyethylene palmitylamide, polyoxyethylene stearyl amide, polyoxyethylene. Examples include oleyl amide, polyoxyethylene coconut amide, polyoxyethylene beef tallow amide, polyoxyethylene hardened beef tallow amide, and the like. These can be used alone or in combination of two or more. Among these, polyoxyethylene oleylamide, polyoxyethylene cocoamide, polyoxyethylene beef amide, and polyoxyethylene cured beef amide are preferable.
[0024]
The surfactants (A) to (D) are all very effective as the dispersant for ice water slurry of the present invention. In the present invention, a combination of two or more of these surfactants may be used. It can be suitably used as a dispersant for ice water slurry. In this case, a combination of the surfactant (A) and the surfactant (B), a combination of the surfactant (A) and the surfactant (D), etc. are particularly effective. Shown and preferred.
[0025]
Moreover, when the surfactant (A) and the aliphatic quaternary ammonium salt (E) below or the surfactant (B) are used in combination, an excellent, stable and fine ice crystal particle water slurry is produced. This is more preferable because it can be expected and a DR effect can be expected.
[0026]
(E) Aliphatic quaternary ammonium salt represented by the following general formula (4)

[Wherein R ⁶ is an alkyl or alkenyl group having 8 to 22 carbon atoms, R ⁷ , R ⁸ and R ⁹ are all alkyl groups having 1 to 5 carbon atoms or (AO) _s H group (where AO is An oxyalkylene group having 2 to 4 carbon atoms, s is a real number of 1 to 5, and at least one of R ⁷ , R ⁸ and R ⁹ is an (AO) _s H group. X ⁻ represents a counter anion. ]
[0027]
In the formula (4), R ⁶ is an alkyl group or alkenyl group having 8 to 22 carbon atoms, preferably 12 to 20 carbon atoms. R ⁶ may be a mixed alkyl group or mixed alkenyl group which is a vegetable or animal natural fatty acid residue.
[0028]
AO represents an oxyalkylene group having 2 to 4 carbon atoms, preferably an oxyethylene group, and s is 1 to 5, preferably 1 to 2.
[0029]
X ⁻ represents an inorganic or organic anion, such as a halogen ion, an acetate anion residue, or a methosulphate anion.
[0030]
Specific examples of the aliphatic quaternary ammonium salt (E) include octyldimethylmono (hydroxyethyl) ammonium chloride, dodecyldimethylmono (hydroxyethyl) ammonium chloride, stearyldimethylmono (hydroxyethyl) ammonium. Chloride, oleyldimethylmono (hydroxyethyl) ammonium chloride, octylmethyldi (hydroxyethyl) ammonium chloride, dodecylmethyldi (hydroxyethyl) ammonium chloride, stearylmethyldi (hydroxyethyl) ammonium chloride, oleylmethyldi (hydroxyethyl) ammonium Chloride, beef tallow methyldi (hydroxyethyl) ammonium chloride, stearyltri (hydroxyethyl) ammonium Chloride, Oreirutori etc. (hydroxyethyl) ammonium chloride and the like, may be used these alone or in combination of two or more. Of these, stearylmethyldi (hydroxyethyl) ammonium chloride, oleylmethyldi (hydroxyethyl) ammonium chloride, and oleyltri (hydroxyethyl) ammonium chloride are preferable.
[0031]
In this case, the blending ratio of the surfactant (A) to another surfactant (for example, the surfactant (B), the surfactant (E), etc.) is a mass ratio, and the interface (A) Activator: other surfactant = 1: 9 to 9: 1, preferably 3: 7 to 7: 3.
[0032]
In the present invention, a well-known sorbitan surfactant tween 80 described in the prior art in combination with the aliphatic quaternary ammonium salt (E) also has excellent performance as a dispersant for ice water slurry. Is.
[0033]
The surfactants (A) to (D), which are dispersants for ice water slurry of the present invention, are preferably 0.001 to 5 mass%, more preferably 0.003 to 0 in total amount with respect to the entire ice water slurry. It is preferable to blend 3 mass%. If the amount of the surfactant is too small, stable and fine ice may not be generated. On the other hand, if it is too much, it may become insoluble in ice water or foam, which is not preferable.
[0034]
Next, the method for using the dispersant for ice water slurry of the present invention is to prepare a surfactant aqueous solution of the present invention having a predetermined concentration and gradually cool it below the freezing point of water. At this time, no stirring may be performed, but cooling is preferably performed while gently stirring. When cooled in this way, fine ice crystals of 0.01 mm to several mm which are fine as a whole are generated. On the other hand, when the surfactant of the present invention is not added, the crystal particles become enormous and the ice crystals grow on the walls of the container and the pipe. Such an inconvenience does not occur in the aqueous agent solution.
[0035]
In this way, an ice-water slurry stably holding ice of 0.01 mm to several mm of fine crystals having an ice content (IPF; ice solid mass ratio) of 5 to 50 mass%, preferably 10 to 40 mass%. Can be obtained.
[0036]
According to the dispersant for ice water slurry of the present invention, it is possible to prepare an ice water slurry composed of fine crystal ice, and when the ice water slurry is directly transported by application to a latent heat transport air conditioning system, it is clogged with piping or the like. This makes it impossible to transport, and because it is a fine ice crystal, it has excellent heat transfer efficiency.
[0037]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, while being able to produce | generate a stable and fine ice crystal particle slurry, the air-conditioning system which applied the latent heat transport which can also be cooled to a low temperature can be obtained very efficiently which also has DR effect. .
[0038]
【Example】
EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not limited to the following Example.
[0039]
[Example 1, Comparative Example 1] Evaluation of ice properties of ice water slurry To a 1 liter beaker, 500 mL of water in which 1000 ppm of various surfactants shown in Table 1 were dissolved was added, and the freezing point was gently stirred on a cool stirrer. Then, the properties of ice formed were visually and manually stirred and judged according to the following evaluation criteria. The results are shown in Table 1. For comparison, the same determination was made for the case where no surfactant was added.
[0040]
<Evaluation criteria>
A: There is no adhesion of ice to the beaker wall surface, there is no fusion of ice crystals, and fine ice is uniformly dispersed.
○: There is almost no adhesion of ice to the beaker wall surface, there is almost no fusion of ice crystals, and fine ice is almost uniformly dispersed.
Δ: Some adhesion of ice to the beaker wall and fusion of ice crystals are seen.
X: The ice adheres to the wall of the beaker remarkably, and the ice crystals fuse together to grow large ice crystals.
[0041]
[Table 1]

[0042]
[Example 2] Evaluation of DR effect Sample No. 1 in Table 1 was used among the surfactant aqueous solutions used for evaluating the ice properties of the ice water slurry. When the apparent viscosity at room temperature was measured for 13, 15, and 16 using a rotating cylinder viscometer (SR-5 made by Rheometric Scientific), an increase in viscosity was observed in all samples.
[0043]
Thus, when viscosity increase is recognized, the presence of rod-like micelles is expected, and the DR effect can be expected for these surfactants.

Claims (2)

(A) A dispersant for ice-water slurry, comprising an aminoacetic acid type betaine surfactant represented by the following general formula (1):

[Wherein R ¹ is an alkyl group or alkenyl group having 14 to 22 carbon atoms, R ² and R ³ are alkyl groups having 1 to 5 carbon atoms or (AO) _n H group (where AO is 2 to 4 carbon atoms) And n is a real number of 1 to 5.) ] Furthermore, the dispersing agent for ice water slurries of Claim 1 containing the at least 1 sort (s) of surfactant chosen from following (B)-(D).
(B) Alkali metal salt, alkaline earth metal salt, amine salt and ammonium salt of vegetable natural fatty acid mainly composed of oleic acid, oleic acid, and alkali metal of animal natural fatty acid based on oleic acid Surfactant selected from salts, alkaline earth metal salts, amine salts and ammonium salts (C) Polyalkoxylates of aliphatic amines represented by the following general formula (2)

(In the formula, R ⁴ represents an alkyl or alkenyl group having 8 to 22 carbon atoms, AO represents an oxyalkylene group having 2 to 4 carbon atoms, and p and q are p ≧ 1, q ≧ 1, p + q = 2 to 100. Is a real number satisfying.)
(D) Polyalkoxylate of aliphatic amide represented by the following general formula (3)

(In the formula, R ⁵ represents an alkyl group or alkenyl group having 7 to 21 carbon atoms, and AO, p, and q have the same meaning as described above.)