JPS5826961B2 - oil/water separation agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an oil-water separation agent that separates oil and water from an oil-water mixture in which the oil and water exist in the form of an emulsion or a particle dispersion.

Examples of cases in which oil and water exist in the form of an emulsion or dispersion include emulsions that occur when heavy oil is washed with water for desalination, emulsions that occur when heavy oil is mixed with rainwater due to an accident, and moisture in crude oil extracted from an oil well. Emulsions produced when crude oil is mixed with water, emulsions produced by washing with water for desalination during crude oil refining, emulsions produced when crude oil and water are simultaneously transferred through transport pipes, cutting oil in wastewater, etc. There are emulsions that are formed when oil flows into the liquid.

These emulsions are of the so-called W2O type, in which water is dispersed in oil, and the so-called 0/W type, in which oil is dispersed in water.These emulsions are broken to separate oil and water into two layers. Physical methods such as heating and centrifugation are used to separate oil and water.

When the emulsion is stable or when the amount of dispersoid is very small compared to the dispersion medium, an oil-water separating agent is used in combination with the physical method as a chemical method.

For example, if water is present in heavy oil as fuel oil, the combustion state becomes unstable.

Normally, when a burner for a boiler is used, if the fuel oil contains 5% or more water, combustion becomes unstable, so the JIS stipulates that general heavy oil has a water content of 2% or less.

Also, in crude oil refining, if there is a large amount of moisture after desalting, topping may occur and may cause trouble to refining equipment.

In such cases, water exists in the oil as a very stable emulsion, and the effect of water separation directly improves combustion efficiency or purification efficiency, and a high-performance water separation agent is required for water separation. Ru.

Conventional oil-water separation agents for such emulsion solutions include various surfactants such as petroleum sulfonates, castor oil sulfates, succinic ester sulfates, polyoxyethylene alkylphenol ethers, and polyoxyethylene polyoxypropylene diethers. agent is used.

When a surfactant is added to an emulsion, it coordinates at the interface between the oil phase and the aqueous phase, and the dispersoids are aggregated and separated by a slight physical action such as stirring or heating.

However, the oil-water separation methods using the various surfactants described above do not have sufficient oil-water separation efficiency or treatment capacity; for example, even if oil and water are separated, an oil layer containing water in the form of an emulsion remains at the interface.

Furthermore, when only a surfactant is added, it is often necessary to use physical methods such as centrifugation and heating in combination, and furthermore, when the physical method is stopped after oil-water separation, the oil-water often emulsifies again.

The present invention relates to a novel oil-water separating agent that is most effective when oil and water exist in an emulsion state or in a particle dispersion state, and is applicable to liquids such as crude oil, refined oil, slop oil, and tar. Any type of oil may be used, but it may be added to a mixture of these liquid oils and water in the form of an emulsion or dispersion.

The oil/water separating agent of the present invention contains a surfactant and a polyamide alone or in combination of two or more thereof as main components.

The surfactant may be any surfactant as long as it has been conventionally used as an oil-water separating agent.

On the other hand, the general formula for polyamide is HO(-QC-R-CONH-R'-NH-).

H (n is suitably an integer of 2 to 10, R is a hydrocarbon with C of 30 to 40, R' is an ethylene group represented by -CH2-CH2-) and has a molecular weight of 1500 to 5000. Use it.

Since polyamide has cationic properties, when added to an oil-water mixture containing water and oil as an emulsion or in a dispersed state, anionic substances are neutralized and oil-water separation performance is improved.

Therefore, one or more polyamides can be freely selected and used.

If necessary, the above oil-water separation agent may be used by mixing it with an organic solvent such as kerosene, butyl cellosolve, or methylnaphthalene, water, or a mixed solvent thereof, or it may be used as is without being mixed with the organic solvent or water at all. May be used.

When the above-mentioned oil-water separating agent is mixed into a solution of oil and water in the form of an emulsion and thoroughly stirred, the emulsion is demulsified and the oil layer is separated into the upper layer and the water layer is separated into the lower layer due to the difference in specific gravity.

In this case, the oil-water interface becomes very clear and can be easily separated.

In particular, the separation time is extremely fast, and emulsion is almost never re-emulsified after oil and water separation.

In summary, according to the present invention, an oil-water separating agent consisting of a surfactant and polyamide is added to an oil-water mixture containing water and oil as an emulsion or in a dispersed state, and the mixture is stirred and mixed very easily and in a short time. Moreover, oil and water can be separated reliably.

Examples of the present invention are described below.

Example 1 Two separating agents (1) to (2) and (1') to (200 volume
After stirring thoroughly for 1 minute, 100 TLl (containing 50 ml of water and 50 ml of heavy oil) was collected in a graduated cylinder, and allowed to stand at 80°C.

Table 1 shows the amount of water separated (b) after 10 minutes, 30 minutes, 1 hour, 2 hours, and 4 hours after standing.

Among the separating agents, (1) and (2) are products of the present invention in which polyamide is added to a surfactant, (1) and (2) are target products in which polyamide is not added.

As is clear from the table above, in the product of the present invention, approximately 40 ml of water in about 50 TLl was separated after 30 minutes, and more than 451 L1 was separated after 1 hour.

On the other hand, those without polyamide added only 4 hours after 4 hours.
The temperature was around 0°C.

Therefore, it has become clear that oil and water can be separated much more quickly than before.

Example 2 Add 10 TLl of water to 90rfLl of Minas crude oil,
A large number of crude oil emulsions were prepared by sufficiently stirring for 1 minute with a homogenizer rotating at 0 rpm.

To this crude oil emulsion, 1100 pp each of (1) to (4) and (1 to (4) separating agent mixtures were added, and 3
After stirring for 0 seconds, put 10011L into a centrifuge tube and add 80
It was left standing at ℃.

Table 2 shows the amount of water separated after 10 minutes, 30 minutes, 1 hour, and 2 hours after standing.

In the separating agent mixture, (1) to (4) are products of the present invention in which polyamide is added to the surfactant, and (1 to (4) are target products in which polyamide is not added.

As is clear from the table above, in the product of the present invention, approximately 8rILe of water was separated in 107711 after 10 minutes, and approximately 9ml was separated after 30 minutes.

On the other hand, the product without polyamide has a 7.
At about TrLl, separation occurred after 2 hours at around 9 yd.

Therefore, it has become clear that the product of the present invention separates oil and water much more quickly than conventional separating agents.

Claims (1)

[Claims] 1. For 10 parts of surfactant, the general formula is HO(-〇C-R-CONH-R'-, NH+nH(n
is an integer of 2 to 10, R is a hydrocarbon having 30 to 40 carbon atoms, R1 is an ethylene group represented by -CH2-CH2-)
An oil/water separating agent whose main component is a polyamide represented by the formula 1, and having a molecular weight of 1,500 to 5,000, either alone or in combination with 0.5 to 5 parts of two or more.