Long-term stable high-temperature drag reducer and preparation method thereof

Abstract

The invention discloses a long-term stable high-temperature drag reducer and a preparation method thereof, and belongs to the technical field of pipeline turbulent flow drag reduction, and the preparation method comprises the following steps: fully dispersing 20-30% of erucamide propyl trimethyl ammonium chloride in water, then adding 60-75% of stabilizer sodium salicylate, fully stirring, and then adding 20-30% of sodium salicylate, and fully stirring; and finally, adding 1%-3% of a defoaming agent and 2%-3% of a preservative. According to the long-term stable high-temperature drag reducer and the preparation method thereof, the drag reducer has the advantages of higher drag reduction rate at 60-110 DEG C, high stability, high shear recovery, low cost, easiness in operation and long drag reduction service life, and effective drag reduction can be maintained within at least two months.

Description

Technical Field

[0001] The invention relates to the technical field of pipeline turbulence drag reduction, and in particular to a long-term stable high-temperature drag reducer and a preparation method thereof. Background Art

[0002] Central heating is always accompanied by huge energy consumption and environmental pollution. In the process of heat transmission, energy is lost in the water pump used to transport hot water and the heat loss during the transportation process. Among them, the energy consumption of water pumps in the central heating system distribution network accounts for a large proportion. The use of drag reducers can greatly reduce pump power consumption and direct heat loss during the transmission process. Adding a small amount of high molecular polymers or certain surfactant additives to the turbulent flow of Newtonian fluids (generally such as water) can introduce viscoelasticity into the flowing working fluid, change the turbulent structure in the flow without significantly changing the viscosity of the fluid, and thus cause turbulent drag reduction.

[0003] Adding drag reducers to the heating system will not only meet the heating demand, but also reduce the pump power consumption and heat loss of the fluid during pipeline transportation, which has high economic and social benefits. However, existing drag reducers have problems such as low resistance to high temperatures, low drag reduction rate and short lifespan. Summary of the invention

[0004] The purpose of the present invention is to provide a long-term stable high-temperature drag reducer and a preparation method thereof, which has good turbulent drag reduction effect, long service life, low cost and easy operation.

[0005] To achieve the above-mentioned purpose, the present invention provides a long-term stable high-temperature drag reducer, the components of the high-temperature drag reducer and the mass fractions of the components include 20%-30% of erucamide propyltrimethylammonium chloride, 60%-75% of sodium salicylate, 1%-3% of a defoamer and 2%-3% of a preservative.

[0006] Preferably, the defoaming agent is one or two of dimethyl polysiloxane, fatty acid polyoxyethylene polyoxypropylene compound and stearic acid.

[0007] Preferably, the preservative is one or both of sodium nitrite and potassium nitrite.

[0008] The present invention provides a method for preparing a long-term stable high-temperature drag reducer, comprising the following steps:

[0009] S1. At room temperature, weigh erucamide propyl trimethyl ammonium chloride according to the set mass fraction and dissolve it in deionized water while stirring continuously;

[0010] S2. Add sodium salicylate weighed according to the set mass fraction to the solution obtained in S1, stir continuously to dissolve it, add water to dilute to the fixed volume, and continue stirring;

[0011] S3. Add defoaming agent and preservative weighed according to a set mass fraction to the solution obtained in S2, and stir continuously to obtain a high-temperature drag reducer.

[0012] Preferably, the mass fraction of erucamidopropyltrimethylammonium chloride in S1 is 20%-30%.

[0013] Preferably, the mass fraction of salicylic acid in S2 is 60%-75%.

[0014] Preferably, the mass fraction of the defoaming agent in S3 is 1%-3%, and the mass fraction of the preservative is 2%-3%.

[0015] Preferably, the stirring time in S1 is 5-10 min.

[0016] Preferably, the first stirring time in S2 is 5-10 min, and the second stirring time is 30-60 min.

[0017] Preferably, the stirring time in S3 is 5-20 min.

[0018] Therefore, the present invention adopts the above-mentioned long-term stable high-temperature drag reducer and its preparation method, which has the following beneficial effects:

[0019] (1) It has a high drag reduction rate at 60-110°C, strong stability and strong shear recovery;

[0020] (2) Sodium salicylate was selected as the stabilizer to achieve the best drag reduction effect and a long drag reduction life, which can maintain effective drag reduction for at least 2 months.

[0021] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a preparation flow chart of a long-term stable high-temperature drag reducer and a preparation method thereof according to an embodiment of the present invention;

[0023] Figure 2 This is a drag reduction effect diagram of a drag reducer prepared in Example 1 of a long-term stable high-temperature drag reducer and a preparation method thereof of the present invention;

[0024] Figure 3 This is a drag reduction effect diagram of a drag reducer prepared in Example 2 of a long-term stable high-temperature drag reducer and a preparation method thereof of the present invention;

[0025] Figure 4 This is a drag reduction effect diagram of a drag reducer prepared in Example 3 of a long-term stable high-temperature drag reducer and a preparation method thereof of the present invention;

[0026] Figure 5 This is a drag reduction effect diagram of a drag reducer prepared in Example 4 of a long-term stable high-temperature drag reducer and a preparation method thereof of the present invention;

[0027] Figure 6 This is a stable test effect diagram of the drag reducer prepared in Example 2 of an embodiment of a long-term stable high-temperature drag reducer and a preparation method thereof of the present invention, wherein (a) represents 30°C, (b) represents 60°C, (c) represents 90°C, (d) represents 100°C, and (e) represents 110°C;

[0028] Figure 7 This is a system diagram of a drag reduction test experiment of a long-term stable high-temperature drag reducer and a preparation method thereof according to the present invention;

[0029] Figure 8 This is a power saving diagram of a pump after adding the drag reducer prepared in Example 2 to a long-term stable high-temperature drag reducer and a preparation method thereof according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0031] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.

[0032] Example

[0033] The invention provides a long-term stable high-temperature drag reducer. The formula of the high-temperature drag reducer is named HDR. The components and the mass fractions of the components include: 20%-30% of erucamidopropyltrimethylammonium chloride, 60%-75% of sodium salicylate, 1%-3% of a defoamer and 2%-3% of a preservative.

[0034] Among them, erucamide propyltrimethylammonium chloride, as a surfactant, will dissociate and destroy the network microstructure inside the solution after being subjected to strong shear stress (such as the situation every time it passes through a centrifugal pump in a liquid circulation system). However, after the strong shear effect disappears, the microstructure will automatically regenerate within seconds, that is, it has a self-repair function. Similarly, its turbulent drag reduction effect will also be restored.

[0035] Whether the surfactant solution has a drag reduction effect during flow depends on whether rod-shaped micelles can be formed in the solution. When the surfactant is dissolved in water, micelle structures will gradually form in the solution. At first, the surfactant molecules exist as single molecules in water, then form aggregates of several molecules, and when the concentration reaches a certain critical value, spherical micelles will form. At higher concentrations, spherical micelles may further evolve into rod-shaped micelles.

[0036] As a stabilizer, sodium salicylate can promote the growth of surfactant micelle system and generate rod-shaped micelles. Such rod-shaped micelle structure can easily form shear-induced structure under the action of shear force. Shear-induced structure can reduce the occurrence of turbulence in the fluid, thereby reducing turbulent shear stress.

[0037] The defoamer is one or two of dimethyl polysiloxane, fatty acid polyoxyethylene polyoxypropylene compound and stearic acid, and its main function is to eliminate or inhibit the foam in the liquid and improve the stability and use effect of the drag reducer. The preservative is one or two of sodium nitrite and potassium nitrite, and its main function is to inhibit the growth of microorganisms, extend the shelf life of the drag reducer and protect the equipment from corrosion.

[0038] The present invention provides a method for preparing a long-term stable high-temperature drag reducer, comprising the following steps:

[0039] S1. At room temperature, weigh 20%-30% erucic acid amide propyl trimethyl ammonium chloride and dissolve it in deionized water, stirring continuously for 5-10 minutes;

[0040] S2. Add 60%-75% sodium salicylate to the solution obtained in S1, stir continuously for 5-10 minutes to dissolve it, dilute with water to the fixed volume, and continue stirring for 30-60 minutes;

[0041] S3. Add 1%-3% of defoaming agent and 2%-3% of preservative to the solution obtained in S2, and stir continuously for 5-20 minutes to obtain a high-temperature drag reducer.

[0042] Example 1

[0043] like Figure 1 As shown, the present invention provides a long-term stable high-temperature drag reducer and a preparation method thereof, comprising the following steps:

[0044] S1. At room temperature (25°C), weigh 100 g of erucic acid amide propyl trimethyl ammonium chloride and dissolve it in 500 mL of water, stirring continuously for 5 min.

[0045] S2. Add 200 g of sodium salicylate to the solution obtained in S1, stir continuously for 5 min to dissolve it, dilute with water to 1 L, and continue stirring for 30 min;

[0046] S3. Add 5 g of defoamer and 5 g of preservative to the solution obtained in S2, and stir continuously for 10 min to obtain a high-temperature drag reducer.

[0047] The drag reducer prepared above was added into the fluid water at 60-100°C at a mass concentration of 1 / 50, and the drag reduction rate was calculated. The results are as follows: Figure 2The drag reduction rate (DR) is defined as the difference between the friction coefficients of water and surfactant solution divided by the friction coefficient of water at the same Reynolds number. The calculation formula is:

[0048]

[0049] In the formula, f N represents the friction factor of water; f D Represents the friction factor of the surfactant solution; ΔP N Represents the friction pressure drop of water at the same flow rate, MPa; ΔP D Represents the friction pressure drop of the surfactant solution at the same flow rate, MPa.

[0050] like Figure 2 As shown in the figure, under the condition of 60-80℃, the curve shows obvious drag reduction effect, and the drag reduction rate increases with the increase of Reynolds number. Under the condition of 90℃, the curve also shows effective drag reduction effect, but the drag reduction rate is slightly lower than that of 80℃. Under the condition of 100℃, the drag reduction rate is significantly lower than that of other temperature conditions, and the drag reduction effect is significantly reduced.

[0051] Example 2

[0052] The present invention provides a long-term stable high-temperature drag reducer and a preparation method thereof, comprising the following steps:

[0053] S1. At room temperature (25°C), weigh 100 g of erucic acid amide propyl trimethyl ammonium chloride and dissolve it in 500 mL of water, stirring continuously for 5 min.

[0054] S2. Add 300 g of sodium salicylate to the solution obtained in S1, stir continuously for 5 min to dissolve it, dilute with water to 1 L, and continue stirring for 30 min;

[0055] S3. Add 5 g of defoamer and 5 g of preservative to the solution obtained in S2, and stir continuously for 10 min to obtain a high-temperature drag reducer.

[0056] The drag reducer prepared above was added into the fluid water at 60-110°C at a mass concentration of 1 / 50, and the drag reduction rate was calculated. The results are as follows: Figure 3 As shown. At 60-100℃, the drag reducer has an obvious drag reduction effect, but at 110℃, the drag reduction rate is significantly reduced and the drag reduction effect is lost. This is because the structure of the drag reducer is destroyed at 110℃, and the friction resistance is significantly increased. Under the conditions of temperature 80℃, fluid flow rate 2.5m / s, and Reynolds number 240000, the drag reduction rate of the drag reducer is the best, and the maximum drag reduction rate is above 70%.

[0057] Example 3

[0058] The present invention provides a long-term stable high-temperature drag reducer and a preparation method thereof, comprising the following steps:

[0059] S1. At room temperature (25°C), weigh 100 g of erucic acid amide propyl trimethyl ammonium chloride and dissolve it in 500 mL of water, stirring continuously for 5 min.

[0060] S2. Add 400 g of sodium salicylate to the solution obtained in S1, stir continuously for 5 min to dissolve it, dilute with water to 1 L, and continue stirring for 30 min;

[0061] S3. Add 5 g of defoamer and 5 g of preservative to the solution obtained in S2, and stir continuously for 10 min to obtain a high-temperature drag reducer.

[0062] The drag reducer prepared above was added into the fluid water at 60-110°C at a mass concentration of 1 / 50, and the drag reduction rate was calculated. The results are as follows: Figure 4 As shown. At 60-100℃, the drag reducer has an obvious drag reduction effect, but at 110℃, the drag reduction rate is significantly reduced and the drag reduction effect is lost. This is because the structure of the drag reducer is destroyed at 110℃, and the friction resistance is significantly increased. Under the conditions of temperature 90℃, fluid flow rate 2.8m / s, and Reynolds number 300000, the drag reduction rate of the drag reducer is the best, and the maximum drag reduction rate is about 73%.

[0063] Example 4

[0064] The present invention provides a long-term stable high-temperature drag reducer and a preparation method thereof, comprising the following steps:

[0065] S1. At room temperature (25°C), weigh 50 g of erucamide propyl trimethyl ammonium chloride and dissolve it in 500 mL of water, stirring continuously for 5 min.

[0066] S2. Add 400 g of sodium salicylate to the solution obtained in S1, stir continuously for 5 min to dissolve it, dilute with water to 1 L, and continue stirring for 30 min;

[0067] S3. Add 5 g of defoamer and 5 g of preservative to the solution obtained in S2, and stir continuously for 10 min to obtain a high-temperature drag reducer.

[0068] The drag reducer prepared above was added into the fluid water at 60-80℃ at a mass concentration of 1 / 50, and the drag reduction rate was calculated. The results are as follows: Figure 5 At 60-80℃, the drag reducing agent has only a weak drag reducing effect, the drag reducing rate is greatly reduced, and the effective drag reducing temperature range is also greatly reduced.

[0069] (1) Stability test

[0070] In practical applications, in addition to the drag reduction performance, drag reduction stability is also a key issue. The drag reducer prepared in Example 2 was added to the drag reduction test system and operated continuously for two months. Drag reduction tests were performed at 30, 60, 90, 100 and 110°C every day. Figure 6 As shown in the figure, when the temperature rises from 30℃ to 110℃, the high temperature will damage the structure of the drag reducer, resulting in a decrease in drag reduction performance. However, when the temperature drops to the effective drag reduction temperature range of the solution the next day, the solution can still effectively reduce drag, and the drag reduction performance has not decreased. After the high temperature destroys the drag reduction effect, the solution can restore to its original drag reduction effect after lowering the temperature, which shows that the solution exhibits strong shear resistance.

[0071] Within two months, as time went by, the drag reduction rate of the solution in the range of 30-100°C did not gradually decrease, and the drag reduction effect did not decrease, which undoubtedly further proved the engineering application value of the solution. At 110°C, the drag reduction effect of the solution was relatively weak within the experimental Reynolds number range, but it may have a better drag reduction effect in a larger Reynolds number range. Therefore, the effective drag reduction time of the drag reducer prepared in Example 2 is greater than 60 days, and the stability is good.

[0072] (2) Power reduction characteristic test

[0073] exist Figure 7 The drag reducer prepared in Example 2 was added to the experimental system shown in the figure, and a drag reduction test experiment was carried out at 20-100°C to obtain the following Figure 8 The power saving diagram of the pump is shown. The power saving (PR%) is defined as the difference between the pump power when water is added to the system and the pump power when the surfactant solution is added to the system divided by the value of the pump power when water is added to the system at the same Reynolds number. The calculation formula is:

[0074]

[0075] In the formula, Power N Represents the pump power when water is added to the system, W; Power D Represents the pump power when the surfactant solution is added to the system, W.

[0076] Under the experimental conditions, the maximum PR% of the solution can reach 28%. Although this result is affected by the overall pipeline design of the experimental system, the characteristics of each pipe fitting and the characteristic curve of the pump, it can still provide a reference for subsequent related research and the engineering application of drag reducers in heating systems.

[0077] Therefore, the present invention adopts the above-mentioned long-term stable high-temperature drag reducer and its preparation method, which has good turbulent drag reduction effect, long service life, low cost and easy operation.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A long-term stable high-temperature drag reducer, characterized in that: The components of the high-temperature drag reducer and the mass fractions of the components include: 20%-30% of erucic acid amide propyl trimethyl ammonium chloride, 60%-75% of sodium salicylate, 1%-3% of a defoamer and 2%-3% of a preservative.

2. A long-term stable high-temperature drag reducer according to claim 1, characterized in that: The defoaming agent is one or two of dimethyl polysiloxane, fatty acid polyoxyethylene polyoxypropylene compound and stearic acid.

3. A long-term stable high-temperature drag reducer according to claim 1, characterized in that: The preservative is one or both of sodium nitrite and potassium nitrite.

4. A method for preparing a long-term stable high-temperature drag reducer as claimed in any one of claims 1 to 3, characterized in that: The following steps are involved: S1. At room temperature, weigh erucamide propyl trimethyl ammonium chloride according to the set mass fraction and dissolve it in deionized water while stirring continuously; S2. Add sodium salicylate weighed according to the set mass fraction to the solution obtained in S1, stir continuously to dissolve it, add water to dilute to the fixed volume, and continue stirring; S3. Add defoaming agent and preservative weighed according to a set mass fraction to the solution obtained in S2, and stir continuously to obtain a high-temperature drag reducer.

5. The method for preparing a long-term stable high-temperature drag reducer according to claim 4, characterized in that: The mass fraction of erucamidopropyltrimethylammonium chloride in S1 is 20%-30%.

6. The method for preparing a long-term stable high-temperature drag reducer according to claim 4, characterized in that: The mass fraction of salicylic acid in the S2 is 60%-75%.

7. The method for preparing a long-term stable high-temperature drag reducer according to claim 4, characterized in that: The mass fraction of the defoamer in S3 is 1%-3%, and the mass fraction of the preservative is 2%-3%.

8. The method for preparing a long-term stable high-temperature drag reducer according to claim 4, characterized in that: The stirring time in S1 is 5-10 min.

9. The method for preparing a long-term stable high-temperature drag reducer according to claim 4, characterized in that: The first stirring time in S2 is 5-10 min, and the second stirring time is 30-60 min.

10. The method for preparing a long-term stable high-temperature drag reducer according to claim 4, characterized in that: The stirring time in S3 is 5-20 min.

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