HU198961B - Additive mixture for crude oils - Google Patents

Description

FIELD OF THE INVENTION The present invention relates to an additive blend for reducing sedimentation of crude oils and crude oil fractions at low temperatures and improving their erulability, particularly in boreholes, tanks, pipelines, and other devices for transmission, transport and storage.

It is known that in paraffins contained in crude oils or crude oil fractions, such as middle distillates, they are crystallized, agglomerated upon cooling and thus cannot meet the requirements for crude oils or crude oil fractions.

It is further known that a number of modifiers have been proposed which have a beneficial effect on the amount of excellent paraffins and their cross-linking ability, thus keeping the crude oil and crude oil fractions liquid even at lower temperatures.

It is also known that low molecular weight ethylene-vinyl acetate copolymers are effective in reducing the melting point of crude oils and crude oil fractions and advantageously affecting their flow properties (German Patent Publication No. 1,147,799 and German Patent Publication No. 2,227,786). document).

Various ethylene-vinyl acetate-based terpolymers are also known, for example terpolymers with dialkyl-vinyl carbinol, which also advantageously affect the flow properties (U.S. Patent Nos. 3,915,668 and 4,001,063).

Also known are various compositions of ethylene-vinyl acetate copolymers and other materials such as aromatic copolymers (U.S. Patent 4,058,371), lauryl acrylic esters (German Patent Publication No. 1,545,287), or non-nitrogen-soluble oil-soluble compounds containing, for example, straight-chain (CH2) n-polymethylene compounds having 10-30 or more linear substituents (German Patent Publication No. 2,156,425).

Other ethylene-vinyl acetate copolymer combinations in which the EVA copolymers differ in vinyl acetate and / or molecular weight have also been proposed as additives (U.S. Patent No. 3,961,916 and German Patent Publication No. 2,156,425). document).

From DE 123 673 a mixture of additives is known which is a viscous ethylene copolymer gach product (component A) having a viscosity of 30-400 cP (140 ° C) and an

Mixture of ethylene polymer and / or ethylene vinyl ester copolymer (component B) having a viscosity of 20-250 cP (140 ° C).

It is also known that the behavior of various middle distillates (heating oils and diesel oils) at low temperatures depends partly on the location and partly on the course of the distillation process (H. Vogel, Compendium Erdöl / kohle, 1978/79, 740-778).

Additives that improve flow and filterability must meet the following requirements:

1) Reduce the freezing point.

2) It must inhibit the growth of paraffin crystals.

3) Decrease the CFPP (Cold Filter Plugging Point) (Cold Filtering Limit).

Due to differences in production, processing, storage, and transport, middle distillates often have to meet requirements that are unattainable by providing an appropriate value such as turbidity, CFPP, or freezing point, and different flow properties. various emulsifying properties must also be taken into account in the case of repair additives.

A very important requirement for flow, transport, or storage, for example, is to prevent sedimentation of paraffin crystals that are excellent below the cloud point.

The flow-enhancing agents known to date have made the dispersion of paraffins in the distillates either inadequate or insufficient.

It is an object of the present invention to provide a mixture of additives to reduce the low temperature sedimentation of crude oil and crude oil fractions which is more effective than the known additives or mixtures of additives, in particular with respect to their dispersing properties.

SUMMARY OF THE INVENTION An object of the present invention is to provide an additive mixture suitable for reducing low-temperature sedimentation, emulsifiability and consisting of ethylene-vinyl acetate copolymer (component A) containing from 20 to 50% by weight of vinyl acetate and having an average molecular weight of 500 to 15 000 g / mol; and

It consists of an oxidized ethylene polymerate (component B) with an average molecular weight of 500-5000 and has a hydroxyl group content of 10-85 mmol / mol -CH2-,

HU 198961 D gamma-lactone group content ester group or tai ketal content ketone group content acid group content

2-15 mmol / mol -CH2 group,

5-45 mmol / mol -CH2-,

10-75 mmol / mole of -CH 2 -,

5 to 50 mmol / mol -CH2 group, and the ratio of component A to component B (99: 1) to (50:50).

In the ethylene n-vinyl ester copolymer, the vinyl ester is preferably vinyl acetate or vinyl propionate.

The other component of the additive mixture according to the invention is oxidized ethylene copolymers and / or polyethylene which contain the following functional groups by oxidation:

OH 10-85 mmol / mol -CH 2 -, gamma lactone group 2-15 mmol / mol -CH2 group, ester 5-45 mmol / mol of -Cl12 group, ketone 10-70 mmol / mol -CH2 group, acid group 5-15 mmol / mol -CH2 group,

The additive mixture according to the invention is used in an amount of 0.001 to 0.5% by weight.

Compound B of the additive mixture according to the invention is prepared as described in GDR 116,625 as follows: 100 kg of polyethylene or ethylene-vinyl acetate copolymer resin in a stainless steel acid-proof reactor 140-160 ° C. Melting at C, oxygen gas was introduced into the reactor and water was added as an inert component. The reaction temperature and the course of the reaction are controlled by the amount of water added to the reactor (heat evaporation through evaporation) and external jacket heating, corresponding to the oxygen feed. After completion of the reaction, the oxygen feed was discontinued, the temperature was rapidly reduced to 120 ° C by the addition of water, and the resulting product was granulated by spraying. The reaction conditions used are summarized in the following table.

The table

Example Temperature water volume let K ml / h.kg liters extra Reaction- Oz added time h 1 / h.kg

Functional groups are -CH 2 -

viz Kcal Hydroxyl ^ -Lac- Reason- Ke- Acid ton space ton 1.2 433 20 210 131,250 10.5 35 18 3.7 9.3 12.0 11.0 3.5.6 433 21 211 131,500 9.5 36 11 2.4 6.1 12.0 6 4 433 25 213 133,000 16.5 55 82 14.6 43.8 68 48 7 433 21 211 131,500 8.0 45 38 7.2 24.6 28.6 24

The composition is determined as follows. The vinyl acetate content was determined by pyrolysis by heating 200 mg of the polymer polymer in 300 mg of pure polyethylene in a pyrolysis flask at 450 ° C for 5 minutes, collecting the resulting gases in a 250 mL round-bottom flask, acetic acid NaJ / KJO3. solution and titrate the liberated iodine with NazS2Cl2 solution.

The determination of the groups introduced by oxidation is determined by IR spectroscopy based on the absorption in the characteristic bands:

Hydroxyl group 3400 cm ⁴ , γ-lactone group 1777 cm * ¹ ,

Ester group 1736 cm * ¹ .

The determination of the ketone and acid groups, since the characteristic bands of the carbonyl and keto groups (1710-1715 cm * ¹ ) show overlap, are carried out by converting the carbonyl groups to thionyl chloride to acid chloride and the absorption is 1798 cm -1. measured at t. The value at 1715 cm-1 after the reaction is typical for the keto group and can be used to determine its concentration.

HU 198961 Β

A particular advantage of the additive mixture according to the invention is that, by improving the behavior of various crude oils and crude oil fractions, such as diesel oil, marine diesel fuel and fuel oil, at low temperatures, they can be stored. it also has a beneficial effect on its properties.

. As is known, the BPA point (Beginn's Dairy Paraffinabschneidung - onset of paraffin precipitation) has not been significantly reduced with the additives so far, only between the freezing point and the CFPP, such as the BPA and the freezing point and the CFPP in crude oil and the oil fractions contain paraffin crystals. Known additives were intended to prevent their growth. If these oils are stored without being moved, for example, in tanks, gravity will, however, result in sedimentation. It is intended to reduce the degree of sedimentation by the additive combination of the present invention, which is provided by the fact that the additive exerts a certain dispersing - emulsifying - effect on the excellent paraffin crystals.

1-2. example

A petroleum fraction having a boiling point of 197-382 ° C having an n-paraffin content of 16.8% by weight and a Cis content of 18.4% by weight was added with the additives in Tables 1 and 2.

The freezing point was determined according to TGL 0-51 583, the BPA was determined according to TGL 0-51 772 and the CFPP was determined according to TGL 33 638.

gamma-lactone group j g ester group ketone group

In Example 1, the concentration of the additive is in each case 0.015% by weight and in Example 2 the concentration of 0.02% by weight. The component 'A' is a ethylene-vinyl acetate copolymer containing 29.3% by weight of vinyl acetate and an average molecular weight of 5 7630, the component 'B' according to GDR 116 625 and oxidized ethylene vinyl acetate as described above. copolymer containing the following functional groups was used: hydroxyl group 18 mmol / mole

-ChI group

3.7 mmol / mole -CH2- group 9.3 mmol / mole -CH2- group 12.0 mmol / mole -CH2- group 11.0 mmol / mole -CH2- group and average molecular weight 4510.

As above, the doped petroleum fraction was kept in a climate chamber at a temperature between BPA and CFPP and the amount of paraffin precipitated was monitored as a function of storage time. The precipitated paraffin collected at the bottom of the vessel was separated, cleaned of the oil residue, and weighed in relation to the total amount of oil.

acid group

Table 1

Example 1

specific Dimension additive without - Comp. -B comp. A + B Blend: A = 99% B = 1% BPA K 265 264 265 264 Derm. point K 254 237 248 238 CFPP K 262 243 258 241 Settling time / sedimented material t% One day 1 0.1 0.1 0.1 2 days 1.5 0.6 0.3 0.4 3 days 4 1.1 0.5 0.5 7 days 9 2.6 0.9 0.8 Day 14 15.4 5.1 2.4 2.0 Day 21 16.4 7.3 2.9 2 4 2 months 27 9.8 6.5 5 7 6 months 78 23.1 20.0 19.1

HU 198961 Β

Table 2

Example 2

specific Dimension additive without .A comp. .B comp. A + B Blend: A = 75% B = 25%. BPA K 266 266 265 265 Derm. point K 254 237 248 236 CFPP K 264 256 258 255 Deposition: time / sedimented material% One day 1.1 0.5 0.4 0:32 2 days 3.6 1.2 0.63 0.5 3 days 3.8 2.0 1.81 1:53 7 days 5.7 2.3 1.9 1:53 14 days 9.5 4.3 3.1 2:11 21 days 20.8 7.4 3.1 2.5 2 months 31.1 8.9 4:04 2.9 6 months 59.3 15.7 14.9 13.3

The values in the table are% by weight OH 11 mmol / mol -CHz- pose. gamma lactone group 2.4 mmol / mol -CH 30 ester 6.1 mmol / mol 3-4. example -CH ketone 12.0 mmol / mol M.p. 185-402 ° C, 19.7- CH2 megX containing n-paraffin (n-Cie content acid group 6 mmol / mol -CH2- 21.6 wt and an average molecular weight of 611. according to. Example 4. Component B is the stone

contained the following functional groups:

Characteristics were determined as described in Example 1. The amount of additive in Example 3 was 0.04% by weight and in Example 4 0.025% by weight. As component A ', it was an ethylene-vinyl acetate copolymer having a vinyl acetate content of 22.1 wt. - 45

In Example 3, component B '(oxidized polyethylene according to U. S. Patent No. 116,625, containing the functional groups formed by the following oxidation: 14.6 mmol / mol -CH2- group 43.8 mmol / mol -CH2- group 68 mmol / mol -CH2 group mmol / mol -CH2 group and average molecular weight 4820

The results obtained are shown in Tables 3 and 4.

HU 198961 Β

Table 3

Example 3

specific Dimension additive without .A 'Comp. .B 'Comp. A + B Blend: A = 50% B = 50% BPA K 264 264 265 264 Oerm. point K 256 236 242 230 CFPP K 260 241 252 239 Settling! time/ sedimented material t% One day 1.7 0.8 1.4 0:43 2 days 3.6 2.1 2.8 0.86 3 days 5.9 3.2. 5.1 1.7 7 days. 10.6 5.4 9.6 2.2 14 days 17.5 8.1 15.4 3.1 21 days 22.4 10.6 20.8 5.4 2 months 35.6 13.8 31.4 8.7 6 months 84.1 21.2 75.9 11.6

Example 4 Table 4 specific Dimension additive without .A 'comp. .B 'Comp. A + B Blend: A = 65% B 35% BPA K 264 264 264 264 Derm. point K 255 231 233 231 CFPP Settling time / settling time t% K 260 249 246 241 One day 1.5 1.1 1.2 0.2 2 days 3.2 2.8 2.2 0.4 3 days 5.6 3.6 2.8 0.9 7 days 11.8 8.9 3.2 1.3 14 days 16.7 11.6 4.1 1.9 21 days 21.8 17.3 6.1 2.4 2 months 33.7 23.4 7.1 2.8 6 months 82.6 28.6 8.5 6.5

The% values in the table represent% by weight.

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HU 198961 Β

Examples 5 and 6

A petroleum fraction boiling in the range of 214 to 388 ° C having an n-paraffin content of 18.7% by weight (n-Cis content: 19.7% by weight) was added with 0.015% by weight of an additive mixture. Additive of 7.5 mol% vinyl acetate ethylene-vinyl acetate copolymer (viscosity 156 mm ² / s at 140 ° C) (average molecular weight 521) (component A ') and oxidized ethylene vinyl acetate copolymer (component .B, U. S. Patent No. 116,625) having a vinyl acetate content of 5.9 mole%, a viscosity of 145 mm ² / s, an acid number of mole / mole of -CH 2 -, and a hydroxyl group content of 11 mole / mole. The content of -CH2-, the ketone group was 12.1 mmol / mol -CH2- and the average molecular weight was 4980. The BPA characteristics were determined as described in Example 1.

The doped mineral oil fractions were placed in a climate chamber and stored at a temperature between BPA and CFPP and the amount of paraffin precipitated as a function of time. Samples were not moved during the study. The paraffin settling at the bottom of the vessels was separated, purified from the residual oil and quantitated on the basis of 5 parts oil. 5-6. are summarized in Table.

5 and 6 · Table

specific Dimension It sits without additive .A comp. , Comp. B A + B Blend A = 75% B = 25% A = 99% B = 1% BPA K 266 266 266 266 266 Derm. point K 256 237 242 236 234 CFPP K 263 252 255 248 246 Sedimentation time / sedimented material One day t% 2.1 1.3 1.6 0.6 0.4 2 days 4.5 3.3 3.8 0.93 0.65 3 days 8.6 7.9 8.2 1.64 0.9 7 days 11.4 9.5 10.3 4.2 1.1 14 days 17.3 15.2 16.8 6.8 2.8 21 days 28.8 24.4 26.2 9.9 4.1 2 months 44.2 35.1 37.3 13.4 7.5 6 months 76.4 65.7 68.6 17.1 12.6 The given % values % By weight present- 45 loose material (80 massX .A ' component and 20% Tenet. , Component B ', 116,625 . East Germany patent) added. THE components: ethylene vinyl acetate

Example 7

We investigated the transport effect of crude oil in a pipeline. The crude oil was passed under a pressure of 0.54 MPa. After 27 days, the pressure had to be continuously raised to 2.4 MPa to deliver the desired amount 55. However, the flow rate was reduced so that the experiment had to be stopped.

After the experiment, the pipeline was cleaned and individual segments were replaced with 60 particularly smooth surface segments. The experiment was repeated for 31 days.

After repeated purification, the crude oil at 314 K had 0.05% by weight of a copolymer of the present invention with a vinyl acetate content of 16.3% by weight and a viscosity of 2870 mm ² / s at 140 ° C. , B ' component: oxidized ethylene-vinyl acetate copolymer, vinyl acetate-tartalroa 14.3 weight percent and a viscosity of 1430 mm ² / s at 140 ° C), an acid group of 24 mmol / mol -CH group, a hydroxyl group, 38 mmol -CH2- / mole ketone 28.6 mmol / mole -CH2-.

Oil delivery was started at a pressure of 0.54 MPa. Surprisingly, this value increased to 1.2 MPa in the first 7 days of the trial, then fell back to 0.61 MPa. Subsequently, the transport pressure increased to only 0.8 g MPa in 5 months.

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Comparative Example 8

Claims (3)

Patent Claim Point For the experiment, an additive mixture known from GD 123,673 was used: .A 'component A: B = 6: 0.2 .B component (vinyl acetate container m: 21 lake- %, viscosity 276 cp / / 140 ° C (vinyl acetate container m: 44 lake- megX, viscosity 41 cp / / 140 ° C) total amount of additive 0.015% by weight. The experiment was carried out as described in Example 1. The results obtained are summarized in Table 7 below. Additive blend for reducing low temperature sedimentation and improving emulsifiability / dispersibility of crude oil and crude oil fractions in boreholes, tanks, pipelines and other equipment for flow, transport and storage, characterized in that the additive contains 20 to 50% by weight of vinyl acetate Of an ethylene-vinyl acetate copolymer having an average molecular weight of 500-15000 - Component A, and an oxidized ethylene polymer of an average molecular weight of 500-5000. .B 'component - consists of a hydroxyl group Table 7 specific Dimension Additive combinations are disclosed in U.S. Patent No. 123,673. GDR standard by BPA K 265 Derm. point K 246 CFPP K 252 Settling time / deposited mass of substance X One day 0.5 2 days 0.8 3 days 2.5 7 days 5.6 14 days 10.7 2 months 12.8 10-85 mmol / mol -CH2-, 2-15 mmol / mol -CH2- group, 5-45 mmol / mol -CH2-, 10-75 mmol / mol -CH2-, 5-50 mmol / mol -CH2- and the weight ratio of components A to B '(99: 1) to (50:50). ton-group content of gamma-lak content ester group content ketone group content Content of 25 acid groups