JPS6025164B2 - Coarse graining material for oil/water separation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a coarse graining material for separating oil-containing water into oil and water.

Many methods have been proposed to treat oil-containing water, but one of the most representative methods is a technology that takes advantage of the fact that the floating speed of oil particles increases when fine oil particles are made coarser. Are known.

It is also known to use lipophilic polyolefin fibers and hydrophilic vegetable fibers as such coarsening materials. However, the coarsening material made of lipophilic fibers generates an excessive pressure difference due to oil adsorption, which makes continuous processing impossible, and also causes the so-called atomization phenomenon (re-atomization of the agglomerated oil).
In addition, there is a problem in that the separation effect is reduced due to this, and there is also a disadvantage in that coarse particles of water (water bubbles) that are surrounded by an oil film that are difficult to float are likely to be produced.

Although the coarsening material made of hydrophilic vegetable fibers does not have the above-mentioned disadvantages and has an excellent coarsening effect, it has the disadvantages of being easily rotted and having insufficient durability. In view of the current situation, the present inventors conducted research to obtain a coarse-grained material for oil/water separation that does not generate differential pressure due to oil adsorption and is resistant to rot and is durable. It was discovered that an extremely excellent coarse-grained material could be obtained by processing it after modification to impart hydrophilic properties, leading to the present invention.

That is, the present invention resides in a granulated material for oil and water scales, which is obtained by subjecting acrylic fibers to a crosslinking treatment with hydroxylamine and a hydrolysis treatment with caustic alkali to impart a degree of swelling of 15 to 70%. Since the material is made of hydrophilic synthetic fibers, it has the great advantage that it not only does not generate lid pressure due to oil adsorption, but also does not rot.

Regarding the granulation mechanism by the coarsening material of the present invention, the smooth passage of oil particles through the coarsening layer is inhibited by the repelling action of the hydrophilic fibers of the coarsening material against fine oil particles. As fine oil particles coalesce in the granulated layer, the coarse oil particles take on a form with the smallest possible surface area due to surface tension, so in principle there is little differential pressure, and there is no misting or blistering. It is pushed out as hardened oil particles to the downstream side of the coarse grained layer.

The coarse-grained material of the present invention uses ordinary acrylic fibers as a starting material and is cross-linked with hydroxylamine and hydrolyzed with caustic alkali to have a swelling degree of 15 to 70%. has a remarkable effect on improving the durability of the hydrophilic portion of the fiber surface layer produced by caustic alkali treatment.

Furthermore, if the degree of swelling of the fiber is less than 15%, sufficient hydrophilicity cannot be obtained, and if it exceeds 70%, it is practically unsuitable in terms of shape stability, compaction, etc. Here, the degree of swelling (%) refers to the degree of hydration of the fiber, where Wb is the dry weight, and WW is the weight after soaking in water for 24 hours and then centrifugally dehydrated for 10 minutes at a rotation speed of 240 pm. This is the value calculated by 烹GoX・oo. To describe the method for producing the coarse graining material of the present invention, 1. 12 to 4 hydroxylamine sulfates and 1.5 to 2 times the amount of dibasic sodium phosphate IZ fire salt as hydroxylamine sulfate were dissolved in the water. Using a treatment solution, acrylic fibers are treated with hydroxylamine sulfate at a ratio of 90 to 10,000 at a concentration corresponding to 15 to 45% oM for 60 to 120 minutes. Then, 30 to 5 females were immersed in a caustic soda solution at room temperature for about 2 hours, or 3 to 5 hours of caustic soda solution was used at a ratio of 90 to 10 at a concentration equivalent to about 8% oM.
Hydrolysis is carried out by reacting at 0qo for 30 to 12 minutes. In this case, in the case of treatment in the usual form of fabric such as needle-punched non-woven fabric, it is necessary to apply a caustic soda solution with a squeezing rate of 10 to 6 mm.
It may be padded with 0 to 180%, sealed in a polyethylene film bag, and reacted for 1 to 7 days for hydrolysis. The coarsening material of the present invention is a hydrophilic acrylic fiber in which a crosslinked structure and a carboxylic acid or an alkali metal salt thereof are introduced into the surface layer of the acrylic fiber. Those into which metal salts are introduced are more suitable. Suitable forms of the coarse graining material of the present invention include a coarse striped fabric, a linear body, a spun yarn laminate, and a needle-punched nonwoven fabric.

The coarse-grained layer may be formed by appropriately seeding these types of hammer-grained materials, and the fiber thickness of the coarse-grained material may range from 2 to 30 mm for stable and filament fibers. For spun yarn, the equivalent of 300 (meter count 3) or less is desirable;
The packing density of the coarse-grained layer is preferably in the range of 0.05 to 0.4 squares/ground, but considering the thickness of the fiber and the form of use,
It is necessary to have a packing density that does not cause compaction under practical conditions. Further, the thickness of the coarse grained layer can be appropriately selected from the range of 1 to 100 mm. From the viewpoint of coarsening, the degree of coarsening of fine oil particles is mainly controlled by the fiber gaps of the lees granulation material in the phase granulation layer and the residence time in the coarsening layer.
It is desirable to reduce the fiber gap, increase the thickness of the phase granulation layer, and set the water flow rate slowly, but on the other hand, this condition increases the processing differential pressure and increases the size of the equipment, so it is difficult to The coarsening layer is constructed by appropriately selecting the fiber thickness of the coarsening material, the packing density of the coarsening layer, and the thickness of the coarsening layer, taking into account the water properties and the desired treatment level. However, it is necessary to treat the water at a reasonable water flow rate.

In addition, the fiber gaps of the coarsening material in the coarsening layer and the thickness of the coarsening layer necessary for phase granulation are based on the results of studies conducted by the present inventors using a cotton-like coarsening material. and 20, 40, 60, 8
The thicknesses of the coarse grained layer corresponding to theoretical fiber gaps of 0, 100, 150〃 are approximately 1, 3, 5, 10, 20, and 20, respectively.
It is 30 arcs.

If necessary, a metal grid, punched metal plate, etc. may be used as a support for coarse-grained material, taking into consideration its strength.
It is desirable to use one that has as wide a water flow area as possible and has large openings.

In addition, when using a flocculent material or a spun material as the form of the lees granulation material, or when using a thick coarse granulation layer, it is advantageous to fill it into a cylinder made of metal or synthetic resin. The water flow rate for oil/water separation using the coarsening material of the present invention affects the degree of treatment, processing stability, differential pressure, etc. Although it is necessary to set the setting by taking into account the gap level and the thickness of the lees layer, it is desirable to control the passing speed of the coarse granulation layer to 3 seconds or less, especially 1.5 to 0.1 From the viewpoint of balance, it is preferable to set the arc/sec.

The coarsening material used in the present invention is attached to the treatment waterway as a coarsening layer, and water is passed through it in an upward flow, a downward flow, or a transverse flow. All kinds of application methods are possible, such as a method in which water is passed inside the tank, but the water to be treated and the treated water are in contact with each other through a coarse grained layer, and the water to be treated moves to the treated water side without passing through the coarse grained layer. It is necessary to avoid this.

Furthermore, if the coarse-grained layers are arranged in multiple stages, the processing level will be improved, and if the coarse-grained layers with different fiber gap levels are installed so as to reduce the fiber gap, the differential pressure will be small, and a high-level treatment will be possible.

The present invention will be explained below with reference to Examples.

Example 1 Using the experimental apparatus shown in FIG. 1, an oil-water chick experiment was conducted under the following conditions.

'1) Test dispersed oil water (water to be treated): B heavy oil was added to well water with evaporation residual light of 15 pm to give an oil concentration of 1000 pm, and dispersed with a 180 pm centrifugal pump to produce milk. The water to be treated had a free solid content.

■ Production of coarse-grained material (modified acrylic fiber): Acrylic fibers (5th, 3rd generation, red, cut length 9. & pine) were mixed with hydroxylamine sulfate 2 times and dibasic sodium phosphate IZK salt 4 times. An aqueous solution containing it was treated at a bath ratio of 1:1 and a temperature of 100 qo for 90 minutes, washed with water and dried, and then treated with 4 ml of sodium hydroxide.
It was soaked in the aqueous solution and allowed to react at room temperature for 24 hours.

These modified acrylic fibers have a thickness of 5 mm and 37 mm, respectively.
,3. and the expansion degree is 30.6% and 33, respectively.
．． 8% and 37.6%. '31 Structure of coarse-grained layer (loaded in the first stage): A metal cylinder with an effective cross-sectional area of 1 slit was filled with a phase-grained material made of various fibers under the following conditions.

a Modified fiber (37d), packing density 0.2 spots/ground, thickness 10mm b Rayon (1 matrix), packing density 0.2 spots/ground,
Thickness 10cm Acrylic fiber (3), packing density 0.2
Spot/ground, thickness 10 arc'4} Water flow rate: 1 skin/sec (
Coarse-grained layer passage speed) '51 Oil concentration measurement: Carbon tetrachloride extraction, infrared absorption spectroscopy (JISKOI02-1
971, however, the measurement cell is a 10-square quartz cell) After filling the experimental device with water, the water to be treated is passed under specified conditions,
The oil concentration after 8 hours was determined, and the results for the coarse grained material made of each fiber were as follows.

a Modified acrylic fiber (37d): 3. Uryu b Rayon (19): 3.3 C Acrylic fiber (No. 3): Due to poor granulation and significant increase in differential pressure, the experiment was stopped after 10 minutes. When the coarse-grained materials were soaked for one month in a bilge collected from a fishing boat, almost no change was observed in the coarse-grained materials made of modified acrylic fibers and ataryl fibers, but the coarse-grained materials made of modified acrylic fibers and ataryl fibers showed almost no change, but the coarse-grained materials made of modified acrylic fibers and ataryl fibers showed almost no change. The entire texture of the grain Q base was slimy and the shape had changed significantly, indicating that it was in a state of decay.

Example 2 A long-term oil-water scale experiment was conducted in exactly the same manner as in Example 1, except for the following three changes to the experimental conditions of Example 1.

[1] Rotational speed of the test centrifugal pump for adjusting dispersed oil and water:
3600 rpm ■ Composition of the granulated layer: a Modified acrylic fiber (54d), packing density 0.3 Menosakaki, thickness 20 skin (loaded in the first stage) b Modified acrylic fiber (
3. phantom), packing density 0.1 female/Sakaki, thickness 10 arc (loaded in the 1st stage) c 2 of the loading in the 1st stage-a, the 2nd stage-b, respectively
Step composition glue Water flow rate: 0.5 m/sec The processing amount per effective cross-sectional area of the lees granulation layer is 36, 30
The oil concentration and differential pressure of the treated water in 00 Elbow are as shown in Table 1, and the c method (two-stage configuration) showed excellent results in terms of treatment level and differential pressure.

Table 1 *72 Vertical female plow; 2 items total fake sea bream publication

[Brief explanation of the drawing]

FIG. 1 shows a specific example of an oil/water separator using the coarse graining material of the present invention. 1: Treated water supply port, 2: First coarse granulation layer, 3, 6: Grouped granulation flotation separation oil layer, 4, 7: Oil discharge port, 5: Second grouped granulation layer, 8: Treated water discharge Exit. OJ diagram

Claims (1)

[Claims] 1. Acrylic fibers are subjected to crosslinking treatment with hydroxylamine and hydrolysis treatment with caustic alkali, and
% swelling material for oil/water separation.