JP4756699B2 - Aqueous deodorant - Google Patents

Description

  The present invention relates to an aqueous deodorant, and relates to a deodorant having a low viscosity, easy handling, excellent storage stability, good diffusibility, a stable deodorizing effect, and high safety. It is.

  Wastewater from households and factories, sewage, rainwater, etc. are collected at a pump station through a sewer pipe and then treated at a sewage treatment plant. The sludge generated here is concentrated, further dehydrated by adding a dehydrating aid or the like, and subjected to landfill disposal, incineration disposal or resource recycling treatment. In organic sludge, there is little dissolved oxygen in the sludge and it begins to rot by anaerobic microorganisms, producing sulfide-type malodorous gases such as hydrogen sulfide and methyl mercaptan, which is an environmental and sanitary issue. In particular, in an open type sludge treatment facility, malodorous gas is diffused from each facility such as a sludge storage tank, and it is difficult to take measures to prevent it. In addition, dehydrated sludge cake after dehydration continues to generate malodorous gases, deteriorating the working environment during storage and transportation until final disposal. Furthermore, bad odors are scattered even in the final landfill, giving unpleasant conditions to nearby residents, and countermeasures for deodorization are important.

  Many antiseptics and deodorizers have been proposed for these deodorizing measures. As one of these disinfectants and deodorants, 2-bromo-2-nitropropane-1,3-diyl diacetate (hereinafter referred to as BNPA) is known (Patent Document 1 and Patent Document 2). This drug is often stored and transported as a liquid composition for application. In general, BNPA is used as a preparation dissolved in a general organic solvent such as glycols, glycol ethers and alcohols, or in an aprotic polar solvent such as N, N-dimethylacetamide and 2-pyrrolidinone.

  In addition, as aqueous preparations, active ingredients, alkylated naphthalenes as solvents, polyoxyethylene canister oil ethers and water as surfactants (Patent Document 3), polyoxyalkylene allyl phenyl ethers, alkylbenzene sulfonic acids An aqueous preparation (Patent Document 4) containing a metal salt and propylene glycol is known.

JP-A-2005-73942 JP 2005-111389 A Japanese Patent Laid-Open No. 5-39202 JP-A-5-246810

  Organic solvents, etc. are generally flammable, and formulations containing many of these may be subject to regulations under the Fire Service Act. Formulations using these are not easy to handle due to their increased viscosity and water. Since the dispersibility is also inferior, the effect may not be stable depending on the use situation. As a method for solving these problems, a method of producing a stable aqueous preparation of a hydrophobic drug is conceivable, but a method generally used for formulating agricultural chemicals using BNPA, a solvent, a surfactant, and water. Even if it is formulated using (Patent Document 3 etc.), the aqueous formulation of BNPA is not necessarily good in chemical stability, and is prone to decomposition such as thermal decomposition and hydrolysis, and is separated during storage. Often occurs and storage stability is poor. In addition, efforts to improve physicochemical properties will cause problems with the deodorizing effect.

  The present invention contains BNPA as an active ingredient, contains water, is not subject to the regulations of the Fire Service Act, is highly safe, has good diffusibility, low viscosity, is easy to handle, has excellent storage stability, and is stable. An object of the present invention is to provide an aqueous deodorant exhibiting a deodorizing effect, particularly a deodorant for sludge treatment.

In summary, the present invention provides:
(1) 2 -Bromo-2-nitropropane-1,3-diyl diacetate 5 to 40% by mass , 10 to 30% by mass of a solvent A below , 5 to 20% by mass of a surfactant B below , and water 33 An aqueous deodorant characterized by containing ~ 80% by mass .
The solvent of A is a solvent containing an ester compound selected from dibasic acid ester or propylene carbonate and propylene glycol in a mass ratio of 1: 3 to 3: 1.
The surfactant of B is a sorbitan compound selected from sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan tristearate, sorbitan monooleate and sorbitan trioleate, and polyoxyalkylene polyalkylene polyamine. Surfactant containing ratio 1: 3 to 3: 1.
(2) The aqueous deodorant according to (1), wherein the dibasic acid ester is selected from dimethyl succinate, dimethyl glutarate, and dimethyl adipate .

  As a result of intensive studies to solve the above problems, the present inventor has water as a main solvent, and blends a specific surfactant according to the blending amount of a glycol solvent, an ester solvent, and BNPA. The present inventors have found that the stability of active ingredients, which cannot be predicted from conventional techniques, is improved, the physicochemical properties are improved, and an excellent deodorizing effect is exhibited.

  The deodorant of the present invention significantly improves the storage stability of BNPA as an active ingredient and is excellent in diffusibility in water. Because it is effective and uses water as the main solvent, it is safe and low in viscosity and easy to handle because it does not fall under the regulations of the Fire Service Act, so it can be used for the entire sludge treatment facility.

  The deodorant of the present invention is an oil-in-water preparation in which BNPA is emulsified and dispersed in water together with a specific solvent and a surfactant.

  Examples of the ester compound as the solvent used in the present invention include dibasic acid esters such as dimethyl succinate, dimethyl glutarate, dimethyl adipate, and propylene carbonate. Particularly preferred is propylene carbonate. Examples of sorbitan compounds as surfactants include sorbitan alkyl esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan tristearate, sorbitan monooleate, sorbitan trioleate, and the like. .

  The blending ratio of the active ingredient BNPA is rationally selected so as to exert a sufficient effect in the facility to which it is applied, but usually it is appropriately selected from the range of 5 to 40% by mass with respect to the total amount of the deodorant. Is preferred. The blending ratio of propylene glycol is 3 to 15% by mass, more preferably 5 to 10% by mass with respect to the total amount of the deodorant. The compounding ratio of the ester compound is 5 to 15% by mass, more preferably 5 to 10% by mass with respect to the total amount of the deodorant. Both are preferably blended at a ratio of 1: 3 to 3: 1. Furthermore, the blending ratio of the surfactant is adjusted so that each of the sorbitan compound and the polyoxyalkylene polyalkylene polyamine is in the range of 2 to 10% by mass. The blending ratio of both is preferably 1: 3 to 3: 1. By appropriately selecting and using from this range, it is possible to obtain a drug that is added to water at the time of use or for quickly emulsifying and dispersing the preparation. In particular, it is preferable to use a mixture of sorbitan monooleate and polyoxyalkylene polyalkylene polyamine. Furthermore, the active ingredient can be well emulsified and dispersed by appropriately changing the composition ratio by using propylene glycol and propylene carbonate.

  When the amount of the active ingredient is 10% or less, the drug of the present invention is obtained by mixing the active ingredient, the solvent and the surfactant until uniform, adding water while stirring at 800 to 1000 rpm, and emulsifying and dispersing. be able to. When the amount of the active ingredient is 11% or more, the viscosity may increase, and it is produced by stirring and emulsifying with a homomixer or the like at 5000 to 12000 rpm, or adding water while kneading with a kneader or the like. An active ingredient, a solvent, a surfactant and an appropriate amount of water are mixed, stirred with a homomixer or the like to obtain an emulsified liquid, and then added with water to obtain an emulsified dispersion without increasing the viscosity. . When a wet grinder such as a sand grinder is used, each raw material is charged at once and pulverized to obtain an emulsified dispersion. Moreover, the obtained emulsified dispersion can be filtered as necessary to obtain a more uniform drug.

  The method of using the agent of the present invention is not particularly limited, and an appropriate method may be selected according to the object of use, the purpose, and the like. For example, a sludge concentration tank, a sludge storage tank, and an agglomeration tank such as a sewage treatment plant A method of adding directly to each facility before dewatering of sludge such as an agent mixing tank, or a method of adding an addition point to the sludge piping that transports between each facility in order to mix sludge and chemicals more efficiently Is applicable. Moreover, it can also add to the sludge after dehydration, ie, a dewatered sludge cake.

  The method for adding the drug of the present invention is not particularly limited, and a method capable of accurately supplying the drug is preferable. For example, a diaphragm type or plunger type metering pump is preferably used. The amount of the chemical used in the present invention depends on the type of sludge, but BNPA in the chemical is an amount that is about 50 to 1000 ppm in terms of the amount of sludge. Increase or decrease the amount as appropriate. Even if it adds more than this, there is no improvement in the deodorizing effect proportional to the dose, which is not economical. It is also possible to dilute the drug with water on site.

  Next, the present invention will be described with reference to examples, comparative examples, and test examples. Note that the present invention is not limited to these. Hereinafter, “parts” means parts by mass.

Each component shown in Tables 1 to 3 was mixed to obtain drugs (Examples and Comparative Examples). In the table,
PG is propylene glycol,
DPG is dipropylene glycol,
PEG is polyethylene glycol # 200,
PC is propylene carbonate,
DBE is a mixture of 10-25% dimethyl adipate, 55-75% dimethyl glutarate and 15-25% dimethyl succinate,
DMS is dimethyl succinate,
DPN is diisopropyl naphthalene,
SSO is sorbitan monoole art,
SPA is a polyoxyalkylene polyalkylene polyamine,
SPC uses polyoxyethylene caster oil ether,
SPD is a polyoxyalkylene allyl phenyl ether and alkylbenzene sulfonic acid metal salt mixture (low HLB type),
SPE indicates a polyoxyalkylene allyl phenyl ether and alkylbenzene sulfonic acid metal salt mixture (high HLB type).

Test Example 1 Heat Resistance Test 100 g of each drug prepared according to Examples and Comparative Examples was put into a glass container, sealed, and stored in a thermostat at 50 ° C. for 7 days, and then the remaining amount of active ingredient was measured by HPLC. The residual rate was determined. The appearance (sediment separation) was observed. The results are shown in Table 3. In Comparative Examples 2 to 4, storage at 50 ° C. caused significant deterioration in physical properties, and no measurement of active ingredients was performed.

Test Example 2 Cold Resistance Test 100 g of each of the drugs prepared according to the examples and comparative examples was put in a glass container, sealed, and stored in a thermostatic chamber at −5 ° C. for 7 days. Observed. The results are shown in Table 4.

  Propylene glycol is superior to low temperatures, but glycerin, dipropylene glycol, and polyethylene glycol # 200 cannot be used because their physical properties are greatly deteriorated.

Test Example 3 Dispersibility Test 400 ml of clean water was placed in a 500 ml beaker, 1 ml of the drug prepared according to the examples and comparative examples was added, and the emulsified dispersion state of the drug was observed. Examples 1-4 and Comparative Examples 1-12 were emulsified and dispersed quickly, but Comparative Examples 13 and 14 were settled at the bottom and were not dispersed.

Test Example 4 Deodorizing Effect Test The chemicals prepared according to the Examples and Comparative Examples were added to sludge slurry (cake water content 80.1%) collected from a sewage treatment plant and stirred at 100 rpm for 30 minutes. Then, each sludge which added the polymer flocculent and performed aggregation and pressing was put into the Tedlar bag, and it preserve | saved in a 30 degreeC thermostat, and measured the odor component density | concentration using the gas detection tube 24 hours and 72 hours later. The results are shown in Table 5. ND in the table indicates less than the detection limit.

Test Example 5 Removal test of dissolved sulfide A water-flowing sodium solution is added to distilled water to adjust the concentration of dissolved sulfide to 125 ppm. While stirring this liquid with a stirrer (200 rpm), each drug (active ingredient concentration 100 ppm) was added. Thereafter, the time-dependent remaining of the dissolved sulfide for 24 hours was measured with a detector tube (Gastec detector tube No. 211M). The results are shown in Table 6.

  From the above test results, the use of a mixture of polyoxyalkylene allyl phenyl ether and alkylbenzene sulfonic acid metal salt as compared with a preparation using sorbitan monooleate and polyoxyalkylene polyalkylene polyamine as a surfactant is Comparative Example 5-5. 6 shows that heat resistance is inferior, and using polyoxyethylene caster oil ether has insufficient cold resistance, as shown for Comparative Examples 8-9. Even when sorbitan monooleate and polyoxyalkylene polyalkylene polyamine are mixed as a surfactant, when glycerin, dipropylene glycol, and polyethylene glycol # 200 are used, the storage stability is insufficient (Comparative Example). 1-4), propylene glycol was excellent. In addition, preparations containing no ester solvent (Comparative Examples 7, 10, 11) and preparations using diisopropylnaphthalene, which is an alkylated naphthalene (Comparative Example 12), were also inferior in heat and cold resistance. Furthermore, preparations using only solvents such as propylene carbonate and dimethyl succinate (Comparative Examples 13 and 14) were inferior in stability and water dispersibility of the active ingredients. The preparation containing propylene carbonate, dibasic acid ester and the like improves the effect of removing dissolved sulfides compared to the preparation not containing (Comparative Example 10). Formulation of propylene carbonate, dibasic acid ester, etc. is not preferable from the physical properties of the preparation, but it is possible by adjusting other solvents and surfactants of the present invention, thereby showing a stable deodorizing effect, and It can be used for the entire treatment facility.

  By using BNPA as an active ingredient, water, main solvent, propylene glycol, surfactant, sorbitan monooleate, etc. and polyoxyalkylene polyalkylene polyamine mixed oil-in-water preparations can be handled with low viscosity. Because it is easy and safe and has excellent diffusibility in water, the active ingredients are distributed evenly when treated in sludge, so that it exhibits a stable deodorizing effect and at the same time it is not as effective as expected from conventional technologies. Improves component stability.

Claims (2)

2-bromo-2-nitropropane-1,3-diyl = diacetate 5 to 40 mass%, 10 to 30 wt% solvent below A, surfactant 5-20% by weight below B, and water 33-80 wt % Aqueous deodorant characterized by containing.
The solvent of A is a solvent containing an ester compound selected from dibasic acid ester or propylene carbonate and propylene glycol in a mass ratio of 1: 3 to 3: 1.
The surfactant of B is a sorbitan compound selected from sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan tristearate, sorbitan monooleate and sorbitan trioleate, and polyoxyalkylene polyalkylene polyamine. Surfactant containing ratio 1: 3 to 3: 1. The aqueous deodorant according to claim 1, wherein the dibasic acid ester is selected from dimethyl succinate, dimethyl glutarate, and dimethyl adipate .