TW201518216A - Method for decreasing viscosity of oil-containing scum and method for decreasing viscosity of oil-containing drainage - Google Patents

Abstract

This invention provides a method for suppressing an increment of viscosity of oil-containing drainage or oil-containing scum without consuming a large amount of energy or an increment of water. A method for decreasing viscosity of oil-containing drainage is provided. The method includes: adding a non-ionic surfactant with a HLB value of 14 or less and a clouding point of 60 DEG C or less to the oil-containing scum. It is preferable that the non-ionic surfactant with the clouding point of 20 DEG C or less is used.

Description

Method for reducing viscosity of oily scum and method for reducing viscosity of oily drainage

The invention relates to a method for reducing viscosity of oily dross and a method for reducing viscosity of oily drainage.

In the rolling treatment of metals such as cold rolling, oil for lubrication and water for cooling are required to produce oily drainage. The oil-containing drainage generated in the metal rolling treatment or the like as described above is separated into moisture and oil in the oil-water separation tank. The separated moisture can be recovered and reused in cold rolling or the like, or sent to a drainage treatment facility. The oil is floated as scum at the time of separation, and the scum containing oil (hereinafter referred to as "oily scum") is pumped from the oil-water separation tank by a pump, and is incinerated as industrial waste.

The viscosity of oily drainage and oily scum is likely to increase due to the influence of oil. The increase in viscosity is remarkable in a low temperature environment, in particular, the oily scum is highly susceptible to high viscosity due to the high concentration of oil, and has a profound influence on the liquid feeding operation by the pump in the oil-water separation tank.

As the oil-water separation treatment of the oil-containing drainage, the technique of Patent Document 1 has been proposed.

Patent Document 1 discloses that in the oil separation tank, after the floating oil is separated from the oily wastewater, the floating oil is further separated in the pressurized floating tank without injecting the chemical, and the floating oil is removed in two stages, and thereafter The emulsion breaking is performed to add an aggregating agent, and the separated oil is agglomerated, and is floated as scum in a pressurized floating concentration tank, and concentrated and removed. However, Patent Document 1 only focuses on oil-water separation, and there is no consideration regarding the viscosity reduction of oil-containing drainage or oil-containing scum.

In order to reduce the viscosity of oily drainage or oily scum, it is effective to increase the temperature. Patent Document 2 discloses a method of increasing the operability in order to fluidize the sludge and heating the sludge.

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 62-121688

[Patent Document 2] Japanese Patent Publication No. Sho 59-38175

However, the warming process of Patent Document 2 has a problem in that the amount of energy consumption in a series of steps becomes large.

Further, with regard to the oil-containing dross, the viscosity can be lowered by adding water, but the moisture of the dross increases due to the fact that a large amount of combustion improver is required at the time of incineration treatment, and oil is contained due to the presence of moisture. The scum has a reduced heat and contains oil floating Reuse of slag becomes difficult.

The present invention has been made in such a situation, and an object thereof is to provide a method for reducing the viscosity of an oil-containing dross or an oil-containing drain without causing a large amount of energy consumption or accompanying an increase in moisture in the oil-containing dross.

In order to solve the above problems, the present invention provides the following [1] to [4].

[1] A method for reducing viscosity of oily dross, which is a nonionic system in which a hydrophile-Lipophile Balance (HLB) value of 14 or less and a clouding point of 60 ° C or less is added to an oily dross. Surfactant.

[2] The method for reducing the viscosity of an oil-containing dross according to [1] above, wherein the cloud point is 20 ° C or lower.

[3] A method for reducing viscosity of oil-containing drainage, which is a nonionic surfactant having an HLB value of 14 or less and a cloud point of 60 ° C or less to an oil-containing drainage.

[4] The method for reducing the viscosity of an oil-containing drainage according to [3] above, wherein the cloud point is 20 ° C or lower.

The viscosity reduction method of the oil-containing dross of the present invention and the viscosity reduction method of the oil-containing drainage can reduce the viscosity of the oil-containing dross and the oil-containing drainage without a large amount of energy consumption or accompanying an increase in moisture in the oil-containing dross.

[Method for reducing viscosity of oily scum]

The method for reducing the viscosity of the oil-containing dross of the present invention is to add a nonionic surfactant having an HLB value of 14 or less and a cloud point of 60 ° C or less to the oil-containing dross.

In addition, the "oil-containing scum" in the present invention includes at least an oil component (floating oil) separated by the oil-water separation tank, and further contains a component other than the oil component such as moisture which is taken out together with the oil component at the time of oil-water separation. And the components added after the separation of the oil and water, such as water dispersed in the oily scum.

The oil-containing dross which can be applied in the viscosity reduction method of the oil-containing dross of the present invention is not particularly limited. Examples of the source of the oil-containing dross include oil-containing drainage water generated in a rolling treatment of a metal such as cold rolling.

The oil content in the oil-containing dross is not particularly limited, but is usually 20% by mass to 80% by mass.

It is considered that the nonionic surfactant having an HLB value of 14 or less and a cloud point of 60° C. or less has an HLB value of 14 or less, and therefore is easily dissolved in the oil-containing dross, and since the cloud point is 60° C. or less, the cloud point is determined. The influence of factors (molecular structure, etc.) becomes easy to contribute to the oil component. In addition, it is considered that when the nonionic surfactant having an HLB value of 14 or less and a cloud point of 60 ° C or less acts on the oil component in the oil-containing dross, the wax component contained in the oil component is inhibited from crystallizing, and the oil-containing float can be lowered. The viscosity of the slag. Further, it is considered that when the nonionic surfactant having an HLB value of 14 or less and a cloud point of 60 ° C or less acts on the oil component in the oil-containing dross, the dispersion of the oil droplets in the oil-containing dross is promoted, thereby reducing the oil droplets. The viscosity of oily dross.

As described above, a nonionic system having an HLB value of 14 or less and a cloud point of 60 ° C or less The surfactant has an effect of lowering the viscosity of the oil-containing dross, thereby reducing the amount of water dispersed in the oil-containing dross. Thereby, the water content in the oil-containing dross is reduced, and the amount of the combustion improver added to the incineration of the oil-containing dross can be reduced. Moreover, by reducing the moisture in the oily scum, the heat of the oily scum can be increased, and the recovered oily scum can be reused.

Further, it is not necessary to heat the oil-containing dross to lower the viscosity, and it is possible to reduce the amount of energy such as steam.

The HLB value of the nonionic surfactant is preferably 11 or less. Further, from the viewpoint of solubility in the oil-containing dross, the HLB value is suitably 8 or more. The cloud point of the nonionic surfactant is preferably 20 ° C or lower.

Examples of the nonionic surfactant having an HLB value of 14 or less and a cloud point of 60 ° C or less include polyoxyalkylene alkyl ethers, polyoxyalkylene fatty acid esters, and polyoxyalkylene di fatty acid esters. And derivatives such as these.

The HLB value can be adjusted by the balance of the hydrophilic group and the lipophilic group. The cloud point can be lowered by extending the polyether chain.

A nonionic surfactant having an HLB value of 14 or less and a cloud point of 60 ° C or less serves to lower the viscosity of the oil-containing dross, and by this action, water enclosed in the hard oil film easily escapes to the outside of the oil film. It can also promote the separation of oil and water. Due to the oil-water separation effect of the oil-containing scum, the moisture of the oil-containing scum can be reduced at each stage of the oil-water separation.

The amount of the nonionic surfactant added to the oil-containing dross having an HLB value of 14 or less and a cloud point of 60 ° C or less is preferably relative to the oil content in the oil-containing dross. It is from 3g/L to 30g/L.

The position at which the sulfonate and/or sulfate salt of the present invention is added is not particularly limited. From the viewpoint of reducing the moisture in the oil-containing dross, it is preferable to add it at a position before the oil-containing dross is obtained, specifically, before the oil-water separation tank or the oil-water separation tank. In addition, from the viewpoint of reducing the amount of addition, it is preferable to add it to a pipe or the like after the oil-water separation tank.

[Method for reducing viscosity of oily drainage]

The viscosity reduction method of the oil-containing drainage of the present invention is to add a nonionic surfactant having an HLB value of 14 or less and a cloud point of 60 ° C or less to the oil-containing drainage.

The oil-containing drainage which can be applied to the viscosity reduction method of the oil-containing drainage of the present invention is not particularly limited and can be applied to any oil-containing drainage. The oil-containing drainage can be referred to as drainage generated in a rolling treatment of a metal such as cold rolling.

The oil content in the oily drainage is not particularly limited, and in the case of the metal rolling treatment, the oil is usually 50 ppm to 500 ppm.

It is considered that the nonionic surfactant having an HLB value of 14 or less and a cloud point of 60 ° C or less has an HLB value of 14 or less, and therefore is easily dissolved in the oily drainage. Since the cloud point is 60° C. or less, the cloud point is determined. The influence of (molecular structure, etc.) becomes easy to act on the oil component. In addition, it is considered that when a nonionic surfactant having an HLB value of 14 or less and a cloud point of 60° C. or less acts on the oil component in the oily drainage, the wax component contained in the oil component is inhibited from crystallizing, and the oily drainage can be reduced. Viscosity. Further, it is considered that if the nonionic surfactant having an HLB value of 14 or less and a cloud point of 60 ° C or less acts on the oil component in the oily drainage, the oil discharge is promoted. The dispersion of oil droplets in the water reduces the viscosity of the oil-containing drainage.

A nonionic surfactant having an HLB value of 14 or less and a cloud point of 60 ° C or less serves to reduce the viscosity of the oil-containing drainage. By this action, water enclosed in the hard oil film easily escapes to the oil film. It can promote the separation of oil and water. Due to the oil-water separation effect, the moisture content of the oil-containing dross obtained in the oil-water separation tank can be reduced.

The amount of the nonionic surfactant added to the oil-containing drainage having an HLB value of 14 or less and a cloud point of 60 ° C or less is preferably 3 g/L to 30 g/L with respect to the oil content in the drainage.

In a preferred embodiment of the nonionic surfactant used in the method for reducing the viscosity of the oil-containing drainage of the present invention, the HLB value is 14 or less and the cloud point is 60° C. or less, and the method for reducing the viscosity of the oil-containing scum according to the present invention. A suitable embodiment of the nonionic surfactant having an HLB value of 14 or less and a cloud point of 60 ° C or less is used in the same manner.

<arbitrarily added ingredients>

In the method for reducing the viscosity of the oil-containing dross of the present invention and the method for lowering the viscosity of the oil-containing drainage, various additives such as an anionic surfactant, a cationic surfactant, etc. may be added to the range which does not impair the object of the present invention. . These additional components may be used alone or in combination of two or more.

[Examples]

Next, the present invention will be described in more detail by way of examples, but the invention is not limited by the examples.

1. Verification of viscosity reduction of oily dross

[Example 1]

The tank containing oil-containing scum (water content: 52% by mass, oil content: 48% by mass, viscosity: 7.6 Pa.s) collected by the oil-water separation tank with cold-rolled oil-containing drainage was carried out 30 to 40 times. Mix and mix. 50 ml of the oily drain which was stirred was poured into a 100 ml test tube, and a nonionic surfactant (polyoxyethylene alkyl ether; manufactured by Sanyo Chemical Industry Co., Ltd., NAROACTY CL-50; HLB value of 10.0, turbidity) was added as a chemical. The point was 20 ° C or less, and the oily dross was injected again to adjust the concentration of the drug to 10 g/L (20.8 g/L with respect to the oil content). The sample in the test tube was stirred with a spatula for 120 seconds, and the oily dross was mixed with the drug, and the viscosity was measured at a sample temperature of 20 °C.

[Example 2 to Example 8], [Comparative Example 1 to Comparative Example 10]

The viscosity of the oil-containing dross was measured in the same manner as in Example 1 except that the chemical was changed to the following.

(Pharmaceutical of Example 2)

Non-ionic surfactant (polyoxyethylene di-fatty acid ester; manufactured by Sanyo Chemical Industry Co., Ltd., IONET DO-400; HLB value is 8.4, cloud point is 20 ° C or less)

(Pharmaceutical of Example 3)

Nonionic surfactant (polyoxyethylene lauryl ether; manufactured by Sanyo Chemical Industry Co., Ltd., EMULMIN NL-70; HLB value is 12.4, cloud point is 58 °C)

(Pharmaceutical of Example 4)

Nonionic surfactant (polyoxyalkylene alkyl ether; Sanyo Chemical Industry Co., Ltd.) Division, NAROACTY ID-40; HLB value is 8.1, cloud point is below 20 °C)

(Pharmaceutical of Example 5)

Non-ionic surfactant (polyoxyethylene alkyl ether; Sanyo Chemical Industry Co., Ltd., SANNONIC SS-50; HLB value of 10.5, cloud point of 20 ° C or less)

(Pharmaceutical of Example 6)

Nonionic surfactant (polyoxyethylene alkyl ether; manufactured by Sanyo Chemical Industry Co., Ltd., SANNONIC SS-90; HLB value is 13.2, cloud point is 56 °C)

(Pharmaceutical of Example 7)

Non-ionic surfactant (polyoxyethylene polyoxypropylene glycol; manufactured by Sanyo Chemical Industry Co., Ltd., NEWPOL PE-61; HLB value is 1.9, cloud point is 24 ° C)

(Pharmaceutical of Example 8)

Nonionic surfactant (polyoxyalkylene alkyl ether; manufactured by Sanyo Chemical Industry Co., Ltd., NAROACTY CL-85; HLB value is 12.6, cloud point is 41 °C)

(Pharmaceutical of Comparative Example 1)

Nonionic surfactant (polyoxyethylene lauryl ether; manufactured by Sanyo Chemical Industry Co., Ltd., EMULMIN NL-110; HLB value is 14.4, cloud point is 97 °C)

(Comparative Example 2)

Nonionic surfactant (polyoxyalkylene alkyl ether; manufactured by Sanyo Chemical Industry Co., Ltd., NAROACTY CL-160; HLB value is 15.2, cloud point is 99 °C)

(Comparative Example 3)

Nonionic surfactant (polyoxyalkylene alkyl ether; manufactured by Sanyo Chemical Industry Co., Ltd., NAROACTY CL-400; HLB value is 17.8, cloud point is 100 °C)

(Comparative Example 4)

Nonionic surfactant (mixture of polyoxyethylene oleyl ether and polyoxyethylene cetyl ether; manufactured by Sanyo Chemical Industries, Inc., EMULMIN 110; HLB value of 13.2, cloud point of 78 ° C)

(Comparative Example 5)

Nonionic surfactant (mixture of polyoxyethylene oleyl ether and polyoxyethylene cetyl ether; manufactured by Sanyo Chemical Industries, Inc., EMULMIN 240; HLB value of 16.1, cloud point of 100 ° C)

(Comparative Example 6)

Nonionic surfactant (polystearate monostearate; manufactured by Sanyo Chemical Industry Co., Ltd., IONET MS-1000; HLB value is 15.7, cloud point is 100 °C)

(Pharmaceutical of Comparative Example 7)

Nonionic surfactant (polyoxyethylene polyoxypropylene glycol; manufactured by Sanyo Chemical Industry Co., Ltd., NEWPOL PE-68; HLB value is 15.7, cloud point is 100 °C)

(Comparative Example 8)

Cationic surfactant (stearyl dimethyl benzyl ammonium chloride; manufactured by Sanyo Chemical Industry Co., Ltd., Cation S)

(Comparative Example 9)

Cationic surfactant (cetyltrimethylammonium chloride; manufactured by Sanyo Chemical Industry Co., Ltd., ECONOL TM-22)

(Pharmaceutical of Comparative Example 10)

Blank (not used)

2. Verification of oil-water separation of oily dross

In Examples 1 to 8 and Comparative Examples 1 to 10, after the viscosity measurement, the test tube sample was stirred with a spatula for 120 seconds, and the oil-containing dross was mixed with the drug, and then at 20 ° C. The environment was allowed to stand for 18 hours under the environment, and the state of oil-water separation was visually observed. As a result, the case where the water layer is observed as 1/5 to 1/4 of the whole is regarded as "○", and the case where the water layer is less than 1/5 is observed as "△", and the oil and water are not separated and the water layer cannot be observed. The situation is "X". The results are shown in Table 1.

According to the results in Table 1, it is known that the HLB value is 14 or less and the cloud point is added. In Examples 1 to 8 which are nonionic surfactants of 60 ° C or lower, the viscosity ( 7.6 Pa.s) of the first oil-containing dross can be greatly reduced. Further, the nonionic surfactants of Examples 2 to 7 were also excellent in oil-water separation effect.

Claims (4)

A method for reducing viscosity of oily dross, which is a nonionic surfactant having a hydrophilic-lipophilic balance of 14 or less and a cloud point of 60 ° C or less. The method for reducing the viscosity of an oil-containing dross according to claim 1, wherein the cloud point is 20 ° C or lower. A method for reducing the viscosity of oil-containing drainage is to add a nonionic surfactant having a hydrophilic-lipophilic balance value of 14 or less and a cloud point of 60 ° C or less to the oil-containing drainage. The method for reducing the viscosity of an oil-containing drainage according to claim 3, wherein the cloud point is 20 ° C or lower.