JPH0633077A - Anti fouling agent for petroleum refining - Google Patents

Abstract

PURPOSE:To obtain an antifouling agent consisting of a reactional product obtained by reacting a higher fatty acid with an N-substituted alkylenediamine in a specific molar ratio and capable of effectively preventing sticking of a stain substance to a petroleum refining equipment such as heat exchanger and fillter. CONSTITUTION:(A) A monocarboxylic acid compound expressed by formula I (R<1> is 9-29C hydrocarbon), e.g. isostearic acid is made to react with (B) an N-substituted alkylenediamine expressed by formula II [R<2> is 10-30C hydrocarbon; (n) is 2-6], e.g. laurylbutylenediamine in a molar ratio A/B of (2/1) to (4/5) at 150-230 deg.C while distilling water produced by the reaction away to provide the objective antifouling agent for petroleum refining, consisting of a reactional product of the component A and the component B. Furthermore, this antifouling agent is diluted with an organic solvent to give handleable viscosity. A 5-500ppm (as active content) of this agent is continuously added to crude oil, light naphtha, heavy naphtha, kerosene, desulfurized residual oil, cracked residual oil, etc., to effectively prevent sticking of stained substance to petroleum refining apparatus.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a petroleum refining stain preventive agent for preventing adhesion of stains in a petroleum refining apparatus.

[0002]

2. Description of the Related Art In the petroleum refining industry, refining facilities have been upgraded in recent years from the viewpoint of addressing environmental problems and increasing the production of white oil. Especially, in the treatment of heavy oil fractions, hydrocracking equipment, Introduction of hydrodesulfurization equipment, catalytic cracking equipment, etc., or stricter operating conditions of these equipment are being promoted. Due to the introduction of these devices or the severer operating conditions, sludge is generated in the residual oil obtained from these devices, which causes problems such as fouling of heat exchangers and clogging of filters. When such a failure occurs, the operation of the apparatus is stopped and the work of removing the dirt deposits is performed. Frequently performing this work leads to the stop of the plant. In order to avoid such a situation, the operating conditions are relaxed or the devices are parallelized, but these are economically extremely disadvantageous.

In order to prevent the adhesion of dirt substances, many methods of adding a dirt preventive agent to a feedstock have hitherto been proposed. Examples of such antifouling agents include amide condensation products of high molecular weight (molecular weight 600 to 3000) monocarboxylic acid and alkylene polyamine (Japanese Patent Publication No. 46-23504), ammonia (Japanese Patent Publication No. 54-69106). , Polyalkyleneamine (JP-A-55-129490), polyoxyalkylene carbamate (JP-A-59-232170)
and so on. However, although addition of these compounds to a feedstock such as crude oil can prevent the attachment of dirt to some extent, it is still not sufficient.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a high performance antifouling agent which prevents adhesion of dirt to heat exchangers and various processing equipment in a petroleum refining process.

[0005]

As a result of intensive studies, the present inventors have found that an amide compound of alkylalkylenediamine is effective as a stain inhibitor, and completed the present invention. That is, in the present invention, the molar ratio of the compound represented by the following formula (A) to the compound represented by the formula (B) is 2
It is an antifouling agent for petroleum refining, which is composed of a reaction product of / 1 to 4/5.

R ¹ COOH (A) R ² NH (CH ₂ ) _n NH ₂ (B) (R ¹ is a hydrocarbon group having 9 to 29 carbon atoms, R ² is 10 to 30 carbon atoms
Is a hydrocarbon group, and at least one of R ¹ and R ² is a saturated hydrocarbon group, and n is 2 to 6. ) Compound of which is a starting material in the formula of the antifoulant of the present invention (A) is a fatty acid R ¹ is a hydrocarbon group of 9-29 carbon atoms, R ¹ is a straight or branched chain saturated or unsaturated Is a hydrocarbon group. Examples of the compound of the formula (A) include decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, montanic acid, melissic acid, oleic acid and erucic acid. There are also beef tallow fatty acid, hardened beef tallow fatty acid, palm oil fatty acid, hardened palm oil fatty acid, hardened rapeseed oil fatty acid, coconut oil fatty acid, hardened fish oil fatty acid, further isomyristic acid isopalmitic acid, isostearic acid, isoarachidic acid, containing these. There are synthetic fatty acids such as isohexacosanoic acid.

In the compound of formula (B), R ² has 10 to 30 carbon atoms.
Is a hydrocarbon group, and n is an alkylalkylenediamine of 2 to 6. Examples of the compound of formula (B) include dodecylethylenediamine, tetradecylpropylenediamine, hexadecylbutylenediamine, octadecylethylenediamine, eicosylhexenediamine, docosylpropylenediamine, tallow alkylpropylenediamine, hydrogenated rapeseed oil alkylpropylenediamine, oleylpropylenediamine. and so on. When the compound of the formula (A) and the compound of the formula (B) are used in a molar ratio of 2/1 to 4/5 and reacted at a temperature of 150 to 230 ° C. while distilling off the reaction product water, the stain of the present invention is obtained. An inhibitor is obtained. Further, R ¹ of formula (A), at least one of R ² of formula (B) is a saturated hydrocarbon group.

Outside of the above-mentioned limited conditions, no sufficient antifouling effect can be obtained. In order to prevent stains using the petroleum refining stain inhibitor of the present invention, for example, the stain inhibitor is diluted with an organic solvent to make the viscosity easy to handle, and 5 to 500 ppm of effective component is continuously injected. Is preferred. If the injection amount is small, the antifouling effect is not exerted. On the contrary, if the injection amount is too large, the effect is not improved and the economical efficiency is deteriorated. A more preferable injection amount is 10 to 100 ppm. Taking the atmospheric distillation process of crude oil as an example, the injection place may be either the crude oil side or the residual oil side, but when adding to the crude oil side, it is preferable to inject at the desalting tank outlet, and to the residual oil side. When adding, it is preferable to inject into the suction side of the distillation column residual oil outlet pump.

[0009]

The antifouling agent for petroleum refining of the present invention effectively prevents adhesion of fouling substances to the oil refining equipment such as the inner surface of a heat exchanger or a filter. Therefore, in various processing steps of the petroleum refining industry, crude oil, light naphtha, heavy naphtha, kerosene, light oil, vacuum gas oil, vacuum residual oil, desulfurization residual oil,
By adding to cracked residual oil or the like, the amount of deposits and deposits deposited can be significantly reduced.

In particular, when the atmospheric residual oil is added to the residual oil from the hydrodesulfurization apparatus or the catalytic cracking apparatus using the residual oil as a raw material, the fouling of the heat exchanger and the clogging of the filter are remarkably reduced, and the work of removing the fouling deposits can be performed. It is possible to reduce the frequency and increase the severity of the operating conditions of the device. The heavy oil refined by adding the antifouling agent of the present invention can also reduce the fouling of heat exchangers and pipes when used in combustion equipment.

[0011]

EXAMPLES The present invention will be described in detail with reference to examples. [Anti-fouling test] The anti-fouling agent is evaluated according to ASTM (D16
Using the NBTL test of 61-64), the following points were changed.

The temperature of the heater part is changed from 180 ° C to 320 ° C,
The cooling tube in the flow channel was changed from glass to iron. Add a predetermined amount of the antifouling agent shown in Table 1 to the sample oil, heat and dissolve it at 80 ° C, perform a test, cool to room temperature, wash the cooling pipe and the protective pipe of the heater part with toluene, and wash with a cloth. It was wiped and the appearance was observed and evaluated according to the following criteria.

◯: Almost no change. B: A little colored brown to black. X: Colored brown to black, or tar-like deposits. The sample oil used in the test is desulfurization residual oil, and its properties are as follows. Density (g / cm ³ ) 0.9103 (JIS K-2249) Flash point (℃) 9.8 (JIS K-2265) Sulfur content (wt%) 0.18 (JIS K-2541) Kinematic viscosity (cSt / 50 ℃) 98.3 (JIS K-2283) Dry sludge (wt%) 0.49 (SMS 742) The results are shown in Table 2.

[0014]

[Table 1] (Note 1) “Emazole 871” Emery Ind. (Note 2) Isopalmitic acid Nissan Chemical Co., Ltd. (Note 3) “HA18GT” Mitsubishi Kasei (Note 4) Isostearic acid Nissan Chemical Co., Ltd. (Note 5) Weight average molecular weight 900

[0015]

[Table 2]

The antifouling agent of the present invention did not give deposits to the cooling pipe and the protective pipe, did not change, and exhibited the antifouling effect even with a small amount of addition. The antifouling agent of the comparative example provided colored or tar-like deposits on the cooling pipe and the protective pipe.

Claims (1)

[Claims] 1. An antifouling agent for petroleum refining, comprising a reaction product of a compound represented by the following formula (A) and a compound represented by the formula (B) in a molar ratio of 2/1 to 4/5. . R ¹ COOH (A) R ² NH (CH ₂ ) _n NH ₂ (B) (R ¹ is a hydrocarbon group having 9 to 29 carbon atoms, R ² is 10 to 30 carbon atoms.
Is a hydrocarbon group, and at least one of R ¹ and R ² is a saturated hydrocarbon group, and n is 2 to 6. )