JPH10252048A - Method for removing oil from surface of water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil removing method which can easily collect only oil from the surface of water, has no secondary adverse effects on the natural environment, and is excellent in profitability. SOLUTION: When powders comprising particles of borosilicate glass in the form of hollow spheres whose surfaces are made hydrophobic or powders comprising particles of silica gel whose surfaces are made hydrophobic are added to C heavy oil floating on water and are agitated, the C heavy oil is aggregated and solidified, so that it can easily be scooped up from the surface of water using a net. Solids containing the C heavy oil collected can be incinerated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing oils from water, which is carried out in order to prevent contamination by the oils when the oils flow into the water such as the sea or lake.

[0002]

2. Description of the Related Art There has been an accident in which a large amount of oil spills out onto the sea, for example, when a ship lands, collides, sinks, or the like. If such oils drift to the shore, they will cause enormous damage to the coastal fisheries industry. Therefore, it is desirable to dispose of such oils at the sea near the accident site as much as possible.

[0003] However, this type of oil is in a liquid state and cannot be collectively recovered using a net or the like, so that recovery at sea is extremely difficult. Therefore, conventionally, dispersants have been applied to oils drifting on the sea. This type of dispersant is usually one containing a surfactant as a main component. By dispersing the oil into fine particles and dispersing it in water, and promoting oxidation and biodegradation in water, the oil dispersant is used to convert the oil. Can be disassembled.

[0004] However, the above dispersants contain compounds having, for example, a phosphoric acid group, a sulfonic acid group, an amino group, an amide group and the like, and these compounds cause secondary environmental pollution. This could have a negative effect on plant and seafood ecosystems.

[0005] In some cases, dedicated vessels for collecting such spilled oil have also been developed. In this method, seawater and oils are collectively pumped into the ship, processed by a centrifuge installed on the ship, separated into seawater and oils, returned to the sea, and only oils are collected. It is.

However, even if such a dedicated ship is used, the amount of oil that can be separated in a unit time is limited. Therefore, considering the cost required for equipment and operation and the recovery effect, the efficiency is extremely high. Was bad. The present invention has been made in order to solve the above problems, and an object of the present invention is to be able to easily recover only oils from water, to have no secondary adverse effects on the natural environment, and to have excellent economic efficiency. An object of the present invention is to provide a method for removing oils.

[0007]

Means for Solving the Problems and Effects of the Invention In order to achieve the above object, an invention according to claim 1 is a method for removing liquid oils flowing out of water from the water, A powder composed of solid fine particles of a silicon oxide compound, which is hydrophobic and lipophilic and floats when introduced into water, is added to the oils and mixed to form a mixture composed of the oils and the powder. And collecting the aggregated mixture from the water.

Here, in the present invention, the silicon oxide-based compound is a compound in which SiO ₂ is a main unit structure and has a high molecular weight by a siloxane bond (Si—O—Si) or the like. , H have a main structure, a part of Si is replaced by Al, B, etc., or a small amount of Na, Fe, Ca, Mg, K
And the like, and these are all collectively referred to as silicon oxide-based compounds.

In general, many of these silicon oxide compounds have a hydroxyl group (-OH) on the surface and exhibit hydrophilicity. However, the powder in the present invention is hydrophobic and lipophilic. Limited to things. Specifically, for example, by chemically reacting an organosilicon compound on the particle surface of a silicon oxide-based compound, a hydrophilic functional group represented by a hydroxyl group is converted to a lipophilic functional group represented by a methyl group. When masked, it becomes hydrophobic and lipophilic. However, the method of hydrophobization itself is not limited in the present invention.

According to the method for removing oils from the water according to the present invention, since the powder is lipophilic, the powder charged into the oils is easily dispersed inside the oils, Moreover,
Since it only has the weight to float when put into water, the part that is put into water floats on the water with oils.
Also, if subjected to an operation such as stirring here, the powder floating on the water is lipophilic, so it is easily taken into the interior of oils, while the powder dispersed in the oils is hydrophobic. Therefore, it is hard to be released into water. Therefore, if such powder is added to and mixed with oils, the mixture of the oils and the powder will aggregate on water.

[0011] The amount of the powder to be added depends on physical properties such as the viscosity of the oil itself, temperature conditions, and the like, and cannot be specified unconditionally. However, since the powder is composed of solid fine particles,
The mixture of oils and powders tends to increase in viscosity as the amount of powder increases, and eventually solidifies to the point where it loses fluidity. You just have to decide the amount. As a guide, when the treatment is carried out in a normal temperature range, there is a substance which solidifies when 2% by weight or more based on the weight of the oil is added, and in many cases, 5 to 10%.
By adding about% by weight, the oils can be solidified to the required hardness. Even if 10% by weight or more is added, further solidification can be achieved, but the effect gradually weakens, and if it exceeds 20% by weight, no noticeable change is observed. Therefore, the amount of powder added is 2 to 20% by weight, preferably 5 to 20% by weight.
It may be about 10% by weight.

After the oils and powders are coagulated and solidified in this manner, the fluidity of the oils has been lost, so that when the coagulated mixture is recovered from the water, it can be recovered using a net or the like. it can. Therefore, recovery can be performed extremely easily compared to recovery of liquid oils from the water.

Further, the powder is composed of solid fine particles of a silicon oxide compound and is the same as a component occupying most of the elements constituting the crust. There is no danger of causing environmental pollution. Furthermore, since the powder can be sprayed on the sea, stirred as needed as needed, and collected collectively using a net, etc. Compared to the case where collection is performed using a machine, no large-scale equipment is required and the economy is excellent.

Since the recovered mixture can be easily incinerated in an industrial furnace or an incinerator, it can be effectively used as fuel or incinerated. Further, since the residue after incineration is silicon oxide, even if it is disposed without special treatment, it does not pollute the environment.

Since the powder used in the present invention must float on water as described above, at least the weight of the powder is smaller than the weight of water of the same volume (usually about 1 g / ml). However, the weight of the powder here does not need to be the mass of the substance itself that forms the fine particles of the powder, but the weight of the powder including the internal space existing in the fine particles. Should be fine.

However, if water enters the internal space after being put into water and the internal space is filled with water,
Even if the weight of the powder before being put into water is lighter than water, the weight of the powder may be heavier than water after being put into water,
In that case, the powder may sink into the water.

Further, considering only that the powder is floated on water, it is desirable that the weight of the powder be smaller than the weight of water of the same volume. In the case of making the particles too light, if the weight is excessively reduced, the strength of the particles themselves is lost, and the internal space cannot be maintained. As a result, the powder may sink into water.

In view of the above, as described in claim 2, the powder is made of fine particles having an internal space into which moisture does not enter, and has a weight per unit volume of 0.2 to 0. It may be adjusted to 0.4 g / ml.
Here, the internal space into which moisture does not enter may be a space that is not completely continuous with the external space. However, even if the internal space is continuous with the external space via the pores, the hydrophobicity near the pores may be reduced. What is necessary is just to have a structure in which the functional group prevents the intrusion of moisture into the pores. In this case, since the moisture does not enter the internal space existing in the particles of the powder, the internal space is not filled with water, and the weight of the powder is larger than that of the water after being poured into water. It will not be.

Further, the weight per unit volume is 0.2 to 0.1.
When adjusted to 4 g / ml, the particles are light enough to float on water and have sufficient particle strength to maintain the internal space, so that the powder is extremely unlikely to sink into water. Incidentally, the weight per unit volume is 0.
If the particle size is less than 2 g / ml, it is extremely light, but if such particles are made of a silicon oxide compound, it is extremely difficult to secure the particle strength enough to maintain the internal space. However, there is a high possibility that the particles will not become particles having an internal space. Even if the particles become particles having an internal space, there is a high possibility that water will enter the internal space with destruction of the particles and sink into water. On the other hand, if the weight per unit volume exceeds 0.4 g / ml, it is difficult to secure sufficient hydrophobicity and tends to be highly hydrophilic. Adsorbs easily and sinks in water.

As described above, in the method for removing oils from water according to the present invention, it is more effective to use the powder as described in claim 2; More specifically, for example, as described in claim 3, the powder is preferably made of silica gel fine particles having a surface subjected to hydrophobic processing.

Such silica gel fine particles are usually
Although it has an internal space that is continuous through the pores in the external space,
Since the surface has been subjected to hydrophobic processing, the hydrophobic functional groups near the pores prevent water from penetrating into the pores, so that water does not penetrate into the internal space even when charged into water. on the other hand,
Since the hydrophobic functional group as described above does not prevent oils from entering the pores, a part of the oils is adsorbed into the particles. Therefore, when such a powder is used, the oils and the powder agglomerate more quickly. Incidentally, the higher the ability to adsorb oils, the better. However, if the silica gel has an oil absorption of 200 ml or more per 100 g of powder, the effect of coagulating the oils is extremely high.

Further, for example, the powder may be made of hollow spherical glass fine particles having a surface subjected to hydrophobic processing. Since such glass fine particles have an internal space independent of the external space, they are extremely lightweight, and water does not enter the internal space even when put into water. Therefore, it is easier to float on water, and this is also suitable as a powder used in the present invention.

The silica gel fine particles according to the third aspect and the glass fine particles according to the fourth aspect have already been used for addition to paints, plastic parts, adhesives, printing inks, papers and the like. It is commercially available and can be easily obtained. Therefore, there is no need to manufacture a dedicated product for treating oils, which is also economically advantageous.

[0024]

Next, an embodiment of the present invention will be described. [Embodiment 1] 1000 ml of seawater from the Sea of Japan is collected,
Fuel oil C (specific gravity 0.91, sulfur content 3.5% by weight) 200g
Was injected and floated on the water surface. There, a powder made of fine particles of hollow spherical borosilicate glass whose surface is subjected to hydrophobic processing (trade name: “Fuji Balloon H30”, manufactured by Fuji Silysia Chemical Ltd., weight per unit volume: 0.2 g / m
1, average particle diameter of 40 μm, pH 7.0) was added and stirred for 2 minutes.

As a result, the C heavy oil coagulated and solidified, and could be easily scooped up from the water surface using a net. The recovered solid containing heavy fuel oil C could be incinerated, and its calorific value was 8,500 kcal / kg. [Embodiment 2] 2000 ml of seawater from the Sea of Japan is collected,
Fuel oil C (specific gravity 0.92, sulfur content 3.2% by weight) 100g
Was injected and floated on the water surface. There, a powder consisting of silica gel fine particles whose surface has been subjected to hydrophobic processing (trade name: "Sirohobic", Fuji Silysia Chemical Ltd.)
(Weight per unit volume: 0.25 g / ml, average particle diameter 2 μm, pH 9.0, oil absorption 250 ml / 100 g)
Was added and stirred for 3 minutes.

As a result, the C heavy oil coagulated and solidified, and could be easily scooped up from the water surface using a net. The recovered solid containing heavy fuel oil C could be incinerated, and its calorific value was 9000 kcal / kg. The embodiments of the present invention have been described above, but the embodiments of the present invention are not limited to the above specific embodiments.

Claims (4)

[Claims] 1. A method for removing liquid oils flowing out of water from the water, comprising solid fine particles of a silicon oxide compound, hydrophobic and lipophilic, and the powder that floats when introduced into water. A method of removing the oils from the water, wherein the mixture is added to the oils and mixed to aggregate the mixture as a mixture of the oils and the powder, and the aggregated mixture is collected from the water. 2. The method according to claim 1, wherein the powder is composed of fine particles having an internal space into which moisture does not enter, and the weight per unit volume is adjusted to 0.2 to 0.4 g / ml. The method for removing oils from water according to claim 1. 3. The powder according to claim 2, wherein the powder is made of silica gel fine particles having a surface subjected to hydrophobic processing.
The method for removing oils from water as described in the above. 4. The method for removing oils from water according to claim 2, wherein the powder comprises fine particles of a hollow spherical glass having a surface subjected to hydrophobic processing.