A long-term stable high-temperature drag reducer and its preparation method

Abstract

The present invention discloses a long-term stable high-temperature drag reducer and its preparation method, belonging to the technical field of pipeline turbulent drag reduction. The steps include fully dispersing 20%-30% of erucylamide propyl trimethyl ammonium chloride in water, then adding 60%-75% of the stabilizer sodium salicylate and stirring well, and finally adding 1%-3% of the defoamer and 2%-3% of the preservative. By adopting the above-mentioned long-term stable high-temperature drag reducer and its preparation method, the present invention has a high drag reduction rate at 60-110°C, strong stability, strong shear recovery, low cost, easy operation, and a long drag reduction life, and can maintain effective drag reduction for at least two months.

Description

Technical Field

[0001] The present 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 associated with significant energy consumption and environmental pollution. During heat transfer, energy is lost in the pumps used to transport hot water and in the heat lost during the transport process. Pumps in the central heating system's distribution network consume a significant portion of the energy consumed. The use of drag reducers can significantly reduce pump power consumption and direct heat losses during the transport process. Adding trace amounts of polymers or certain surfactant additives to the turbulent flow of a Newtonian fluid (typically water) can introduce viscoelasticity into the fluid, altering the turbulent structure without significantly changing the fluid's viscosity, thereby reducing turbulent drag.

[0003] Adding drag reducers to heating systems can meet heating demand while reducing pump power consumption and heat loss during pipeline transportation, resulting in high economic and social benefits. However, existing drag reducers suffer from high temperature resistance, low drag reduction rates, and a 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 objectives, 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% erucamidopropyltrimethylammonium chloride, 60%-75% sodium salicylate, 1%-3% defoaming agent and 2%-3% 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 erucamidopropyltrimethylammonium 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, dilute with water to the fixed volume, and continue stirring;

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

[0012] Preferably, the mass fraction of erucylamide propyl trimethyl ammonium 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 defoamer in S3 is 1%-3%, and the mass fraction of 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, by adopting the above-mentioned high-temperature drag reducer with long-term stability and its preparation method, the present invention has the following beneficial effects:

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

[0020] (2) Selecting sodium salicylate as the stabilizer achieves the best drag reduction effect, and has a long drag reduction life, and can maintain effective drag reduction for at least 2 months.

[0021] The technical solutions of the present invention will be further described in detail below through the drawings and embodiments. Description of the Drawings

[0022] Figure 1 is the preparation flow chart of an embodiment of a high-temperature drag reducer with long-term stability and its preparation method of the present invention;

[0023] Figure 2 is the drag reduction effect diagram of the drag reducer prepared in Example 1 of an embodiment of a high-temperature drag reducer with long-term stability and its preparation method of the present invention;

[0024] Figure 3 is the drag reduction effect diagram of the drag reducer prepared in Example 2 of an embodiment of a high-temperature drag reducer with long-term stability and its preparation method of the present invention;

[0025] Figure 4 is the drag reduction effect diagram of the drag reducer prepared in Example 3 of an embodiment of a high-temperature drag reducer with long-term stability and its preparation method of the present invention;

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

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

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

[0029] Figure 8 It is the power saving diagram of the pump after adding the drag reducer prepared in Example 2 of the long-term stable high-temperature drag reducer and its preparation method according to the present invention. Detailed implementation manners

[0030] The technical solution of the present invention will be further described below with reference to the drawings and examples.

[0031] Unless otherwise defined, the technical terms or scientific terms used in the present invention should have the ordinary meanings understood by those with ordinary skills in the field to which the present invention belongs.

[0032] Examples

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

[0034] Among them, erucylamide propyl trimethyl ammonium chloride, as a surfactant, after being subjected to strong shear stress (for example, the situation when passing through a centrifugal pump each time in a liquid circulation system), the network microstructure inside its solution will also be dissociated and damaged. However, after the strong shear action disappears, this microstructure will automatically regenerate within the time order of 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-like micelles can be formed in the solution. When the surfactant is dissolved in water, a micelle structure will gradually form in the solution. At first, the surfactant molecules exist as single molecules in water, and then form aggregates of several molecules. When the concentration reaches a certain critical value, spherical micelles will be formed. At higher concentrations, the spherical micelles may further evolve into rod-like micelles.

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

[0037] The defoamer is one or two of dimethyl polysiloxane, fatty acid polyoxyethylene polyoxypropylene compound, and stearate. 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. 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 preparation method of a long-term stable high-temperature drag reducer, comprising the following steps:

[0039] S1. At room temperature, weigh 20%-30% of erucamide propyl trimethyl ammonium chloride and dissolve it in deionized water, and continuously stir for 5-10 min;

[0040] S2. Add 60%-75% of sodium salicylate to the solution obtained in S1, continuously stir for 5-10 min to dissolve it, add water to dilute and make up the volume, and continue to stir for 30-60 min;

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

[0042] Example 1

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

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

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

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

[0047] Add the drag reducer prepared above to the flowing water at 60-100 °C at a mass concentration of 1 / 50, and calculate the drag reduction rate. The results are as Figure 2As shown in the figure. The drag reduction rate (DR) is defined as the value obtained by dividing the difference between the friction factors of water and surfactant solution by the friction factor of water at the same Reynolds number. The calculation formula is as follows:

[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 frictional pressure drop of water at the same flow rate, MPa; ΔP D represents the frictional pressure drop of the surfactant solution at the same flow rate, MPa.

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

[0051] Example 2

[0052] The present invention provides a high-temperature drag reducer with long-term stability and its preparation method, including the following steps:

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

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

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

[0056] Add the drag reducer prepared above to the flowing water at 60 - 110 °C at a mass concentration of 1 / 50, and calculate the drag reduction rate. The results are as Figure 3 shown. At 60 - 100 °C, the drag reducer has an obvious drag reduction effect, while at 110 °C, the drag reduction rate decreases significantly and the drag reduction effect is lost. This is because the structure of the drag reducer is damaged at 110 °C, and the frictional resistance increases significantly. Under the conditions of a temperature of 80 °C, a fluid flow rate of 2.5 m / s, and a Reynolds number of 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 erucamide propyl trimethyl ammonium chloride and dissolve it in 500 mL, and continuously stir for 5 min;

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

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

[0062] Add the drag reducer prepared above to flowing water at 60 - 110 °C at a mass concentration of 1 / 50, calculate the drag reduction rate, and the results are as Figure 4 shown. At 60 - 100 °C, the drag reducer has an obvious drag reduction effect, while at 110 °C, the drag reduction rate decreases significantly and the drag reduction effect is lost. This is because the structure of the drag reducer is damaged at 110 °C and the frictional resistance increases significantly. Under the conditions of a temperature of 90 °C, a fluid flow rate of 2.8 m / s, and a Reynolds number of 300,000, 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, and continuously stir for 5 min;

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

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

[0068] Add the drag reducer prepared above to flowing water at 60 - 80 °C at a mass concentration of 1 / 50, calculate the drag reduction rate, and the results are as Figure 5 shown. At 60 - 80 °C, the drag reducer only has a weak drag reduction effect, the drag reduction rate decreases greatly, and the effective drag reduction temperature range also shrinks greatly.

[0069] (1) Stability test

[0070] In practical applications, in addition to paying attention to the drag reduction performance, the drag reduction stability is also a key issue. The drag reducer prepared in Example 2 was added to the drag reduction experiment system and continuously operated for two months. Drag reduction experiments were carried out at 30, 60, 90, 100, and 110 °C every day. As Figure 6 shown, when the temperature rises from 30 °C to 110 °C, the high temperature will damage the structure of the drag reducer, resulting in a decrease in the 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 does not decrease. After the high temperature destroys the drag reduction effect, the solution can recover to the original drag reduction effect after the temperature is lowered, indicating that the solution exhibits strong anti-shear ability.

[0071] Within two months, as time goes by, the drag reduction rate of the solution does not gradually decrease within the range of 30 - 100 °C, and the drag reduction effect does not decline either. This undoubtedly further proves the engineering application value of the solution. At 110 °C, the drag reduction effect of the solution is relatively weak within the experimental Reynolds number range, but it may have a better drag reduction effect within 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] In the Figure 7 shown experimental system, the drag reducer prepared in Example 2 was added, and a drag reduction test experiment was carried out under the conditions of 20 - 100 °C to obtain the pump power saving diagram as shown in Figure 8 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 pump power when water is added to the system at the same Reynolds number. Its 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 the drag reducer in the heating system.

[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 solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions of the present invention or make equivalent replacements, and these modifications or equivalent replacements do not enable the modified technical solutions to deviate from the spirit and scope of the technical solutions 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 each component include: erucic acid amide propyl trimethyl ammonium chloride 20%-30%, sodium salicylate 60%-75%, defoamer 1%-3% and preservative 2%-3%. The sum of the mass fractions of each component is 100%; The defoamer is one or two of dimethyl polysiloxane, fatty acid polyoxyethylene polyoxypropylene compound and stearate; The preservative is one or two of sodium nitrite and potassium nitrite; The preparation method of the long-term stable high-temperature drag reducer is the following steps: S1. At room temperature, weigh erucic acid amide propyl trimethyl ammonium chloride according to the set mass fraction and dissolve it in deionized water, and continuously stir; S2. Add sodium salicylate weighed according to the set mass fraction to the solution obtained in S1, continuously stir to dissolve it, add water to dilute and make up the volume, and continue to stir; S3. Add the defoamer and preservative weighed according to the set mass fraction to the solution obtained in S2, and continuously stir to obtain the high-temperature drag reducer.

2. The long-term stable high-temperature drag reducer according to claim 1, characterized in that, The stirring time in S1 is 5-10 min.

3. A long-term stable high-temperature drag reducer according to claim 1, characterized in that, The first stirring time in S2 is 5-10 min, and the second stirring time is 30-60 min.

4. A long-term stable high-temperature drag reducer according to claim 1, characterized in that, The stirring time in S3 is 5-20 min.

Images