JPH01231909A - Antifoaming agent and antifoaming process - Google Patents

Abstract

PURPOSE:To carry out biological treatment safely and to improve foam breaking effect and antifoaming effect remarkably by using an antifoaming agent obtd. by combining a specified addition product of glycol with an esterified product thereof. CONSTITUTION:An antifoaming agent is obtd. from a mixture consisting of a compd. expressed by formula I and a compd. expressed by formula II and/or III, and regulating a proportion of the compd. II and/or the compd. III to 5-55wt.%. In formulas, (l) is an integer 0-30; (m) is an integer 10-100; (n) is an integer 0-50; R1 is 17C alkyl group, alkenyl group; when >=2 alkylene oxide groups are present, the compd. is a block or random addition product. The antifoaming agent is used more effectively if it is added to an easily foaming liquid when the foam surface reaches at the set position while detecting the surface.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a novel antifoaming agent and a novel antifoaming method.
The present invention relates to defoaming Oki J and a defoaming method that exhibit effective foam-breaking and foam-inhibiting effects with a low contamination rate, particularly against foam failures generated in the biological treatment process of human waste treatment facilities.

[Conventional technology]

In the biological treatment process at human waste treatment facilities, the amount of salt left behind varies greatly depending on the season, and depending on the operating conditions, a large amount of foam may be generated, causing major operational troubles.
There are cases where driving becomes difficult.

In particular, recent human waste treatment facilities do not require dilution water.
More and more cases are being adopted of non-dilution, high-load treatment, which requires a small installation space and significantly reduces maintenance and management costs. 11. JI direction is seen.

For the foam generated from these human waste treatment facilities, one or more compounds such as dry alcohol fatty acid ester, silicone, kamako soap, mineral oil, and half ester are added for the purpose of foam breaking and foam suppression. They are used as antifoaming agents depending on the processing situation.

Antifoaming agents that generally interact with surfactants include 11) Antifoaming agents with propylene oxide and ethylene oxide added to higher alcohols.

(2) An antifoaming agent containing gold, a higher fatty acid ester of an ethylene oxide adduct of a higher fatty acid, or a higher fatty acid ester of a higher fatty acid with globylene oxide/JO product.

and so on.

[Problem that the invention seeks to solve]

In the case of the above-mentioned non-dilution, high-load treatment, the sludge in the sieving tank must be maintained at a high concentration, so the sieve water temperature creates conditions in the tank that make it easy to foam. To deal with these foaming problems, the antifoaming agent used in I1N cannot be said to have sufficient foam-breaking and foam-inhibiting effects, and depending on the situation, the defoaming agent may be increased.
It needed to be addressed.

However, in the case of human waste treatment facilities, the antifoaming agents used do not have a negative effect on the treatment because they are used under the restricted conditions of biological treatment, and moreover, the antifoaming agent that is used does not have a negative effect on the treatment, and moreover, the antifoaming agent that is used in the treatment facility loses its antifoaming effect. You are required to do so.

The antifoaming agents listed above, either singly or as a combination of two or more, may have excellent functionality depending on the application, or may have some drawbacks if they are limited to antifoaming agents for human waste treatment facilities. There is.

For example, silicone-based compounds do not have sufficient fast-acting or long-lasting properties, and may leave a layer of silicone oil on the inner walls of sedimentation tanks, requiring post-treatment.Also, mineral oil-based compounds do not release free oil. This causes problems such as inhibiting biological treatment9 and leading to functional decline.

On the other hand, the foam-breaking and foam-inhibiting effects of synthesized surfactant-based antifoaming agents vary depending on their type, form, number of calomoles of propylene oxide and ethylene oxide, and combinations, etc., and there are problems with quick-acting, sustainability, etc. I was disappointed.

In particular, the foaming components generated from human waste treatment facilities are thought to be caused by substances adsorbed and concentrated in activated sludge, such as extracellular polymers in activated sludge, and the foam itself has extremely high viscosity. A large amount of chemicals were required to defoamer.

The inventors of the present invention have made extensive studies to solve all of the problems in the conventional technology, and as a result, we have developed a self-emulsifying type iIR that is safe for biological treatment and has excellent foam and foam-inhibiting effects.
We have discovered a standard antifoaming agent.

[Means for solving problems]

The present invention is based on the general formula % formula % (wherein l is 0 to 30, m is 10 to 100, and n is 0
represents an integer of ~50, R4 represents a C17 alkyl group or alkenyl group, and the alkylene oxide group is 2
If there are more than one ridge, it must be a block or a random adduct. ) An antifoaming agent consisting of a mixture of compound I represented by the formula I and compound iris and/or compound tsun, characterized in that the blending ratio of the compound holder and/or compound holder to the mixture is 10 to 50 percent. 1j0 and 011 Defoaming tension When adding to the foaming liquid, the foam surface level 14? This defoaming method is characterized in that the defoaming material is added by detection.

In the present invention, when l is larger than 30, the hydrophilicity becomes large and the defoaming power becomes extremely low at room temperature.

Furthermore, when m and n are larger than 100 and 50, respectively, lipophilicity increases and self-emulsifying property and diffusibility become worse.

R1 of the compound represented by Issakurin and Otori is C17H55
- represents an alkyl group or an alkenyl group, and other groups are not preferred.

For example, if the number of carbon atoms in R1 is 016 or less, the antifoaming power will be weak, and if it is more than 018, the self-emulsifying property will be poor.

In addition, the compounding ratio of the compound represented by formula 1 and/or layer in the antifoaming agent is most preferably 10 to 50% Arashimin.
When blended in one portion, it exhibits remarkable effects on foam-breaking and foam-inhibiting effects.

The antifoaming agent of the present invention has the same performance whether it is used in the form of a stock solution or emulsified in water. Also, do not use it if mixed with solvents, etc.

The antifoaming agent of the present invention may be added at a ratio of ~30~/l to 101ψ/l to be treated.

The compound represented by the general formula I used in the present invention can be prepared by carrying out an addition reaction in the presence of an all-alkaline catalyst such as ethylene glycol, glopylene glycol and/or butylene gelyl.

On the other hand, the compounds represented by formulas 1 and 1 obtained by the above method undergo an esterification reaction with 1w primary fatty acids in the presence of an esterification catalyst such as halatoluenesulfonic acid. Alternatively, it can be obtained by a dehydrochlorination reaction with a fatty acid chloride, or by transesterification using a lower alcohol ester.

It is also possible to produce the desired substance by directly carrying out a total addition reaction with alkylene oxide.

In addition, the defoaming method using the defoaming material described above is based on the foaming property of the original note. i. When the body is biologically treated and foaming occurs, add the foam, or set up a tester at the appropriate location and control it so that it is added when the foam level reaches the set position. is preferred.

EXAMPLE The antifoaming effects of the antifoaming agent of the present invention and conventional products were compared and studied using the following method.

Test method: The test equipment is a transparent acrylic column with a diameter of 60φ and a length of 1000 mm, and a transparent acrylic column with a diameter of 100φ and a length of 800 mm on the outside to heat the sample 7 fr/b. It was established as

Batsusa adopted the defeaser stone method, which pumps out air through a diffuser installed at the bottom of the column.

For the test, the sample was exposed to a certain number of air for 1 to 2 minutes, and the FC bubble was adjusted to a certain height using a light weight.
The bubble was stopped, the antifoam was applied to the narrow side of the upper reservoir, and the state of disappearance of bubbles (t) was determined (bubble breaking effect). Furthermore, after the bubbles disappear,
Bubble foaming was performed again using a fixed amount of air, and the height of the bubbles was measured over time from immediately after the flashing to the 8th section. (foam suppressing effect).

The above is about the foam breaking and foam suppressing effects as well as the effectiveness of valley guard removal.
We conducted a comprehensive evaluation.

(1) Target sample: Undiluted high-load treatment sludge from the dusting tank (2)
Test amount: 1p (3) Bumping air amount: 2e/min (4) Discharge 1'@! Agent fE person rate: 10 +n9 /
(3) The antifoaming agents tested were 6 types of invented products and 4 types of conventional products.
f O* is 6, #details are shown in Table 1, and the results are shown in Table 2.

Table 3 shows the results of a comparative study of the defoaming effects of the defoaming agent of the present invention and conventional products in a non-dilution, high-load processing facility.

In the test, the antifoaming agent was injected as a stock solution or diluted 50 times with water while the injection bong metal ON-art was operated so that the height of the foam was maintained at a constant level using a foam level meter.

The results are shown in Table-3.

As a result, when the product of the present invention is used, the antifoaming effect is 2.6 times better than that of the American product when using the diluted injection method, and 1.7 times more effective when using the undiluted solution method, and approximately 100 times more effective than the conventional product. 40-b fruit was obtained.

A similar effect can be obtained when a mixture with a compound is used.

〔Effect of the invention〕

As detailed above, the antifoaming agent of the present invention has the following excellent effects.

(l) Excellent fast-acting (foam-breaking effect) and long-lasting (foam-inhibiting effect) against foam problems caused by urinary treatment facilities, and stable treatment with a small amount of added filtration. can be expected.

(2) The product of the present invention has excellent emulsion stability, and when it is diluted with water and used in an emulsified state, there is no difference from the kneading injection method, and there are no particular problems in terms of performance.

(3) The product of the present invention does not cause residues to accumulate on the equipment and equipment, and there are no female prisoners that may impede biological treatment, so there are no particular problems in treatment even if it is used continuously for a long period of time.

Patent applicant Ebara Infilco Co., Ltd. Ebara Research Institute Co., Ltd. NICCA Chemical Industry Co., Ltd.

Claims (1)

[Claims] 1. General formula HO-[(C_2H_4O)_l-(C_3H_6O)
＿m-(C_4H_8O)_n〕H...I ▲There are mathematical formulas, chemical formulas, tables, etc.▼...II ▲There are mathematical formulas, chemical formulas, tables, etc.▼...III (However, in the formula, l is 0 to 30 and m is 10 to 100. , n is 0
It represents an integer of ~50, R_1 represents an alkyl group or alkenyl group of C_1_7, and when two or more types of the above alkylene oxide groups are present, it is a block or random adduct. ) Compound I and compound II and/or compound II represented by
I, and the compound II and/or
Or an antifoaming agent characterized in that the blending ratio of compound III is 5 to 55% by weight. 2. A defoaming method characterized in that when adding the defoaming agent according to claim 1 to a foaming liquid, the defoaming agent is added by detecting a set foam surface position. .