阅读说明：本技术 一种生物质酚醛树脂降滤失剂及其制备方法和应用 (Biomass phenolic resin filtrate reducer and preparation method and application thereof ) 是由 单海霞 王中华 位华 周启成 周亚贤 张鑫 于 2020-05-08 设计创作，主要内容包括：本发明提供了一种生物质酚醛树脂降滤失剂,具有式I结构,式I中,n为0～3,m为7～12。本发明提供的生物质酚醛树脂降滤失剂绿色环保、降滤失性能较好,抗盐能力较强,可生物降解。本发明还提供了一种生物质酚醛树脂降滤失剂的制备方法及应用。本发明提供的生物质酚醛树脂降滤失剂的制备方法环保、温和、简单,应用成本低。(The invention provides a biomass phenolic resin filtrate reducer which has a structure shown in a formula I, wherein n is 0-3, and m is 7-12. The biomass phenolic resin fluid loss agent provided by the invention is green and environment-friendly, has good fluid loss performance and strong salt resistance, and can be biodegraded. The invention also provides a preparation method and application of the biomass phenolic resin fluid loss additive. The preparation method of the biomass phenolic resin filtrate reducer provided by the invention is environment-friendly, mild and simple, and has low application cost.)

1. A biomass phenolic resin fluid loss additive has a structure of formula I:

in the formula I, n is 0-3; m is 7 to 12.

2. The biomass phenolic resin fluid loss additive according to claim 1, wherein n is 1-2 and m is 8-11.

3. A preparation method of a biomass phenolic resin fluid loss agent comprises the following steps:

reacting cardanol, polyethylene glycol, paraformaldehyde, sodium metabisulfite, sodium sulfite and water to obtain the biomass phenolic resin filtrate reducer.

4. The method according to claim 3, wherein the mass ratio of cardanol, polyethylene glycol, paraformaldehyde, sodium metabisulfite, sodium sulfite and water is (260-320): (20-25): (36-72): (20-60): (20-60): (800-1000).

5. The method according to claim 3, wherein the preparation method of the biomass phenolic resin fluid loss additive specifically comprises the following steps:

1) adding cardanol, polyethylene glycol, water and paraformaldehyde in sequence, and mixing to obtain a first mixture;

2) adding sodium metabisulfite into the first mixture in several times to obtain a second mixture;

3) adding sodium sulfite into the second mixture in several times to obtain a third mixture;

4) heating the third mixture to 65-80 ℃, reacting for 20-30 min, then continuously heating to 100-105 ℃, and reacting for 30-60 min to obtain a fourth mixture;

5) and adding water into the fourth mixture for several times, and reacting to obtain the biomass phenolic resin filtrate reducer.

6. The method according to claim 5, wherein the mixing in step 1) is carried out under stirring at a speed of 250 to 300 rpm;

the mixing time in the step 1) is 10-20 min.

7. The method according to claim 5, wherein the sodium metabisulfite is added in the step 2) in a divided manner 4-5 times.

8. The method according to claim 5, wherein the sodium sulfite is added in step 3) 4 to 5 times.

9. The method of claim 5, wherein the reaction in the step 4) is carried out under stirring at a speed of 250 to 300 rpm.

10. An aqueous drilling fluid comprising the biomass phenolic resin fluid loss additive of claim 1 or the biomass phenolic resin fluid loss additive prepared by the method of claim 3.

Technical Field

The invention belongs to the technical field of petroleum industry, and particularly relates to a biomass phenolic resin filtrate reducer as well as a preparation method and application thereof.

Background

With the rapid increase of the oil and gas resource demand in the world and the progress of drilling technology, the investment of exploration and development of oil and gas resources in deep strata is increased by countries in the world. Oil gas resources to be explored in China are mainly distributed in Tarrichwood, Querconager, Lauda, Tuhao, Sichuan and other basins, 73% of the resource amount is buried in a deep layer, and underground conditions are extremely complex, so that deep well and ultra-deep well oil gas drilling and matched development technologies become key factors for restricting oil gas resource development.

The high-temperature high-pressure fluid loss additive is a key treating agent of high-temperature drilling fluid and plays an important role in stabilizing the well wall and protecting an oil-gas layer. The sulfomethyl phenolic resin (SMP for short) is a good high-temperature-resistant fluid loss additive, contains benzene rings in the structure, has excellent long-term high-temperature stability and thermal stability (less than 180 ℃), is a product which is widely applied at home and abroad and difficult to replace all the time, and is almost suitable for various systems. However, with the severe environmental protection situation, the following problems exist in the products: (1) the SMP is mainly prepared from fossil resources, has poor degradability and large price fluctuation, and the SMP is mainly prepared from formaldehyde and phenol, has a structure containing benzene rings, is nontoxic, but lacks special degrading bacteria in the nature, has poor biodegradability, and has limited application in certain areas with higher environmental requirements; (2) residual phenol has certain toxicity, and residual phenol and oligophenol have certain toxicity in the production process, and although many means and measures are adopted, the residual phenol and oligophenol are still difficult to completely remove, and the residual phenol and oligophenol released into the air can affect the atmospheric environment and the human health; (3) the used sulfonated drilling cuttings and waste water has high COD, large chroma, low biodegradability, large treatment and disposal difficulty and high treatment cost. Therefore, the loss control agent of biomass synthetic resin with good degradability and green production process is urgently needed to be researched and conforms to the development direction of green chemistry.

Disclosure of Invention

In view of the above, the invention aims to provide a biomass phenolic resin fluid loss additive, and a preparation method and an application thereof.

The invention provides a biomass phenolic resin filtrate reducer, which has a structure shown in a formula I:

in the formula I, n is 0-3; m is 7 to 12.

In the invention, n is preferably 1-2, m is preferably 8-11, and more preferably 9-10, and m and n are integers.

According to the invention, the biomass phenolic resin fluid loss additive naturally contains a high-temperature-resistant benzene ring structure, and the ortho-position of phenolic hydroxyl in the structure is provided with long-chain alkane, so that the temperature resistance is further improved by utilizing the space volume and the steric effect; the adsorption point of the space body type structure of the structure can improve the adsorption, adsorption thickness and inhibition on the clay, so that the clay has excellent filtration loss reduction performance; meanwhile, the substitution degree of an ortho-para group in the cardanol structure is high, the degradability can be obviously improved, the toxicity is reduced, and the product is green and environment-friendly.

In the invention, the molecular general formula of the biomass phenolic resin fluid loss additive is C_43+46mH_{72-4n+75m-4mn}S_mO_{6m+ 2}Na_mWherein n is 0-3, and m is an integer of 7-12. In the invention, the molecular weight of the biomass phenolic resin fluid loss additive is preferably 6066-9800, the biomass phenolic resin fluid loss additive is a brownish red viscous liquid in appearance, and a 5% aqueous solution based on a dry basis is a light reddish brown transparent liquid.

In the invention, the mass fraction of the biomass phenolic resin fluid loss additive on a dry basis is more than or equal to 30%, the cloud point salinity is more than or equal to 150g/L, the high-temperature and high-pressure fluid loss at 180 ℃ is less than or equal to 25mL, the apparent viscosity is less than or equal to 35mP.s, and the biomass toxicity EC is₅₀The value is more than or equal to 30000mg/L, and the biodegradability is BOD/COD_Cr≥0.25。

The performance test of the biomass phenolic resin fluid loss additive provided by the invention is carried out according to industrial standards SY/T5094 plus 2017 filtration loss additive sulfomethyl phenolic resin SMP for drilling fluid and SY/T6787-2010 technical requirement for water-soluble oilfield chemical environmental protection, and the detection result shows that the dry basis content of the biomass phenolic resin fluid loss additive is 31-35%, the cloud point salinity is 150-160 g/L, the high-temperature and high-pressure filtration loss at 180 ℃ is 14-23 mL, the apparent viscosity is 26-30 mPa.s, and the biomass toxicity EC is₅₀The value is 320000-480000 mg/L, and the biodegradability BOD/COD_Cr0.31 to 0.54.

The biomass phenolic resin fluid loss agent provided by the invention is green and environment-friendly, has good high temperature resistance, salt resistance and fluid loss reduction characteristics, can be used as a substitute of fluid loss agent SMP for drilling fluid, has good biodegradability, is environment-friendly, and has good ecological safety.

The biomass phenolic resin filtrate reducer provided by the invention is a green and nontoxic substance, has good biodegradability, and has no stimulation to human bodies and environment by itself and decomposed products.

The invention provides a preparation method of a biomass phenolic resin filtrate reducer, which comprises the following steps:

reacting cardanol, polyethylene glycol, paraformaldehyde, sodium metabisulfite, sodium sulfite and water to obtain the biomass phenolic resin filtrate reducer.

According to the invention, cardanol, paraformaldehyde, sodium metabisulfite, anhydrous sodium sulfite and water are mixed and then put into a container with a stirring device and a condensing device for reaction, the reaction can be uniformly carried out by adopting stirring and condensation, and the reaction temperature can be kept constant as a good heat dissipation mode.

In the invention, alcoholic hydroxyl active groups are still remained after the synthesis reaction, the viscosity of a terminal product can be controlled by adjusting the reaction temperature and the reaction time, the product can be further reacted under the low temperature condition due to the existence of alcoholic hydroxyl, the effect of reducing water loss is achieved, ether bonds in the product are easy to break under the high temperature condition, the effect of reducing the viscosity is achieved, the thickening phenomenon of a drilling fluid system is ensured not to occur, the rheological property of the whole system is not influenced, and the water solubility and the salt resistance of the biomass phenolic resin can be increased by introducing a sulfonated group.

The preparation method of the biomass phenolic resin filtrate reducer provided by the invention takes cardanol and paraformaldehyde as raw materials, adopts 'one-pot' polycondensation and sulfonation, has no generation of three wastes in the whole process, solves the problems of free phenol, residual aldehyde and the like in phenolic resin in the synthetic process of the prior art, and eliminates potential harm to human bodies and the like caused by volatilization of the raw materials.

In the invention, the mass ratio of cardanol, polyethylene glycol, paraformaldehyde, sodium metabisulfite, sodium sulfite and water is preferably (260-320): (20-25): (36-72): (20-60): (20-60): (800-1000), more preferably (270-310): (21-24): (40-70): (30-50): (30-50): (850-950), most preferably (280-300): (22-23): (50-60): (35-45): (35-45): 900.

in the present invention, the polyethylene glycol is preferably polyethylene glycol 600.

In the present invention, the sodium sulfite is preferably anhydrous sodium sulfite.

In the invention, the preparation method of the biomass phenolic resin fluid loss additive preferably comprises the following steps:

1) adding cardanol, polyethylene glycol, water and paraformaldehyde in sequence, and mixing to obtain a first mixture;

2) adding sodium metabisulfite into the first mixture in several times to obtain a second mixture;

3) adding sodium sulfite into the second mixture in several times to obtain a third mixture;

4) heating the third mixture to 65-80 ℃, reacting for 20-30 min, then continuously heating to 100-105 ℃, and reacting for 30-60 min to obtain a fourth mixture;

5) and adding water into the fourth mixture for several times, and reacting to obtain the biomass phenolic resin filtrate reducer.

In the present invention, the mixing in step 1) is preferably performed in a four-port reaction vessel, and the feeding order in step 1) cannot be changed; the mixing in the step 1) is preferably carried out under the condition of stirring, and the stirring speed is preferably 250-300 rpm, more preferably 260-290 rpm, and most preferably 270-280 rpm.

In the invention, cardanol is not mutually soluble with water at room temperature, but polyethylene glycol 600 is used as a phase transfer catalyst, which has affinity to mutually incompatible two phases, can promote reaction, promote the transfer rate of reactants in the two phases and improve the conversion rate of products. Along with the rise of the temperature, the solubility of paraformaldehyde is gradually increased, and after the cardanol is added, the polyethylene glycol 600 and a certain amount of water are added, so that the gradual dissolution of the cardanol and the paraformaldehyde can be realized to participate in the reaction, and the purpose of homogeneous reaction is achieved, therefore, the material feeding sequence in the step 1) cannot be changed, the material feeding sequence is also a key process of the reaction, and special attention is needed in the synthesis process.

In the invention, the sodium metabisulfite is added in the step 2) in a divided manner, preferably under the condition of stirring, wherein the stirring speed is preferably 250-300 rpm, more preferably 260-290 rpm, and most preferably 270-280 rpm. In the invention, the sodium metabisulfite is preferably added for 4-5 times, the mass of the sodium metabisulfite added each time is the total mass of the sodium metabisulfite needing to be added, divided by the adding times, and the sodium metabisulfite is added each time and then stirred for 10-20 min, for example, 20-60 parts by weight of sodium metabisulfite is added for 4-5 times, and 4-15 parts by weight of sodium metabisulfite is added each time.

In the invention, the sodium metabisulfite is added in small amount for multiple times, so that the sodium metabisulfite can be well mixed uniformly, time is provided for the hydrolysis of the sodium metabisulfite to generate the sodium bisulfite, the sodium bisulfite is an important sulfonating agent, and the sulfonating agent is a key raw material for preparing the biomass phenolic resin filtrate reducer and is used for providing hydration groups in products, which is related to the salt resistance and the dissolving capacity of the filtrate reducer.

In the invention, the sodium sulfite is added in the step 3) in a divided manner preferably under the condition of stirring, and the stirring speed is preferably 250-300 rpm, more preferably 260-290 rpm, and most preferably 270-280 rpm. In the invention, sodium sulfite is preferably added in 4-5 times, the mass of the sodium sulfite added each time is the total mass of the sodium sulfite to be added divided by the adding times, and the sodium sulfite is added each time and then stirred for 10-20 min, for example, 20-60 parts by weight of sodium sulfite is added in 4-5 times, and 4-15 parts by weight of sodium sulfite is added each time.

In the invention, the sodium sulfite is added for a plurality of times in a small amount, so that the sodium sulfite can be well and uniformly mixed, and the hydrolysis speed of the anhydrous sodium sulfite can be effectively controlled, the anhydrous sodium sulfite is hydrolyzed to generate sodium bisulfite, a sulfonated group is provided, and hydroxide radical is released, so that the effect of maintaining the pH of a reaction system is achieved; in the step 3), sodium sulfite is added for the first time, the sulfonation reaction starts to be carried out, the sulfonation reaction is an exothermic reaction, and in order to ensure the continuous and stable reaction, the adding time of the step 3) is preferably controlled to be completed within 20 min.

In the present invention, the reaction in step 4) is preferably carried out under stirring conditions, and the stirring speed is preferably 250 to 300rpm, more preferably 260 to 290rpm, and most preferably 270 to 280 rpm. In the invention, the temperature of the third mixture is preferably raised to 70-75 ℃ for reaction for 25min, and then raised to 102-103 ℃ for reaction for 40-50 min.

In the present invention, the reaction in step 5) is preferably carried out under stirring conditions, and the stirring speed is preferably 250 to 300rpm, more preferably 260 to 290rpm, and most preferably 270 to 280 rpm. In the invention, water is preferably added for 4-6 times, the mass of the water added for each time is the total mass of the water to be added divided by the adding times, and the reaction is carried out for 20-30 min after the water is added for each time, for example, 100-225 parts by weight of water is added firstly and the reaction is carried out for 20-30 min; then adding 100-225 parts by weight of water, and continuing to react for 20-30 min; and (4) adding 4-6 times of water in sequence, continuously reacting for 60-90 min, and discharging.

In the invention, the water is added in the condensation reaction process in the step 5) to mainly control the viscosity of the system so as to obtain the biomass phenolic resin fluid loss additive with good fluidity, thereby being beneficial to field use.

In the invention, the mass ratio of the water in the step 1) to the water in the step 5) is preferably (100-200): (600-900).

The invention provides a water-based drilling fluid which comprises the biomass phenolic resin fluid loss additive in the technical scheme or the biomass phenolic resin fluid loss additive prepared by the method in the technical scheme.

Compared with the prior art, the biomass phenolic resin fluid loss additive provided by the invention has the advantages that the synthetic raw materials are natural biomass, the source is wide, the price is low, the environmental compatibility is good, the renewable biomass resources such as cardanol are used for replacing non-renewable fossil raw materials such as phenol to produce products, the dependence on petrochemical resources is reduced, and the recycling economy with high utilization and low emission is realized. The biomass phenolic resin filtrate reducer provided by the invention is mild in preparation process, environment-friendly, free of three wastes and low in cost. The biomass phenolic resin filtrate reducer prepared by the invention is environment-friendly, has good filtrate reduction performance, strong salt resistance and biodegradability, and is a widely applicable filtrate reducer for water-based drilling fluid. Biodegradable BOD₅/COD_CrUp to 0.31, is an easily degradable product, and has biological toxicity EC₅₀The value reaches 320000mg/L, the product is nontoxic, compared with SMP, the biodegradability is improved by more than 20 times, and the biodegradability is improved by more than 32 times; the compatibility with well slurry is good, and the high-temperature and high-pressure filtration loss is 14.0mL (the standard is less than or equal to 25mL) according to the evaluation of SY/T5094-2017; the anaerobic/aerobic conditions can be biodegraded, and the treatment and disposal difficulty of the drill cuttings and the waste water can be obviously reduced.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other examples, which may be modified or appreciated by those of ordinary skill in the art based on the examples given herein, are intended to be within the scope of the present invention.

The starting materials used in the following examples of the present invention are all commercially available products.

Example 1

Adding 260 parts by weight of cardanol, 20 parts by weight of polyethylene glycol 600, 100 parts by weight of water and 36 parts by weight of paraformaldehyde into a four-port reaction kettle with a reflux device in sequence, and stirring for 10min at a stirring speed of 250rpm to obtain a mixture 1; keeping the stirring speed at 250rpm, adding 20 parts by weight of sodium metabisulfite into the mixture 1 by 4 times, adding 5 parts by weight of sodium metabisulfite each time, and stirring for 10min to obtain a mixture 2; adding 20 parts by weight of anhydrous sodium sulfite into the mixture 2 for 4 times, adding 5 parts by weight of anhydrous sodium sulfite each time, and stirring for 10min to obtain a mixture 3; heating to 65 ℃, reacting for 20min, then continuously heating to 100 ℃, and reacting for 30min to obtain a mixture 4; and adding 175 parts by weight of water into the mixture 4 every 20min, adding 4 times of water in total, continuing to react for 60min, and discharging to obtain a biomass phenolic resin filtrate reducer liquid product.

According to the industrial standards SY/T5094-2017 filtration loss reducer sulfomethyl phenolic resin SMP for drilling fluid and SY/T6787-2010 technical requirement for environmental protection of water-soluble oilfield chemical agents, the performance of the biomass phenolic resin filtration loss reducer prepared in the example 1 is detected, and the results are shown in Table 1.

Example 2

Adding 320 parts by weight of cardanol, 25 parts by weight of polyethylene glycol 600, 200 parts by weight of water and 72 parts by weight of paraformaldehyde into a four-port reaction kettle with a reflux device in sequence, and stirring for 20min at the stirring speed of 300rpm to obtain a mixture 1; keeping the stirring speed at 300rpm, adding 60 parts by weight of sodium metabisulfite into the mixture 1 by 5 times, adding 12 parts by weight each time, and stirring for 20min to obtain a mixture 2; adding 60 parts by weight of anhydrous sodium sulfite into the mixture 2 by 5 times, adding 12 parts by weight of anhydrous sodium sulfite each time, and stirring for 20min to obtain a mixture 3; heating the temperature to 80 ℃, reacting for 30min, then continuously heating to 105 ℃, and reacting for 60min to obtain a mixture 4; and adding 133 parts by weight of water into the mixture 4 every 30min, adding 6 times of water in total, continuing to react for 90min, and discharging to obtain a biomass phenolic resin filtrate reducer liquid product.

According to the industrial standards SY/T5094-2017 filtration loss reducer sulfomethyl phenolic resin SMP for drilling fluid and SY/T6787-2010 technical requirement for environmental protection of water-soluble oilfield chemical agents, the performance of the biomass phenolic resin filtration loss reducer prepared in the example 2 is detected, and the results are shown in Table 1.

Example 3

Adding 290 parts by weight of cardanol, 23 parts by weight of polyethylene glycol 600, 150 parts by weight of water and 48 parts by weight of paraformaldehyde into a four-port reaction kettle with a reflux device in sequence, and stirring for 15min at a stirring speed of 280rpm to obtain a mixture 1; keeping the stirring speed at 280rpm constant, adding 40 parts by weight of sodium metabisulfite into the mixture 1 by 4 times, adding 10 parts by weight of sodium metabisulfite each time, and stirring for 15min to obtain a mixture 2; adding 40 parts by weight of anhydrous sodium sulfite into the mixture 2 by 5 times, adding 8 parts by weight of anhydrous sodium sulfite each time, and stirring for 15min to obtain a mixture 3; heating to 73 ℃, reacting for 25min, then continuously heating to 103 ℃, and reacting for 45min to obtain a mixture 4; and adding 150 parts by weight of water into the mixture 4 every 25min, adding 5 times of water in total, continuing to react for 75min, and discharging to obtain a biomass phenolic resin filtrate reducer liquid product.

According to the industrial standards SY/T5094-2017 filtration loss reducer sulfomethyl phenolic resin SMP for drilling fluid and SY/T6787-2010 technical requirement for environmental protection of water-soluble oilfield chemical agents, the performance of the biomass phenolic resin filtration loss reducer prepared in the example 3 is detected, and the results are shown in Table 1.

Example 4

Adding 300 parts by weight of cardanol, 25 parts by weight of polyethylene glycol 600, 150 parts by weight of water and 50 parts by weight of paraformaldehyde into a four-port reaction kettle with a reflux device in sequence, and stirring for 20min at a stirring speed of 250rpm to obtain a mixture 1; keeping the stirring speed at 250rpm constant, adding 60 parts by weight of sodium metabisulfite into the mixture 1 by 4 times, adding 15 parts by weight of sodium metabisulfite each time, and stirring for 15min to obtain a mixture 2; adding 20 parts by weight of anhydrous sodium sulfite into the mixture 2 by 5 times, adding 4 parts by weight of anhydrous sodium sulfite each time, and stirring for 15min to obtain a mixture 3; heating to 70 ℃, reacting for 30min, then continuously heating to 100 ℃, and reacting for 60min to obtain a mixture 4; and adding 175 parts by weight of water into the mixture 4 every 30min, adding 4 times of water in total, continuing to react for 90min, and discharging to obtain a biomass phenolic resin filtrate reducer liquid product.

According to the industrial standards SY/T5094-2017 filtration loss reducer sulfomethyl phenolic resin SMP for drilling fluid and SY/T6787-2010 technical requirement for environmental protection of water-soluble oilfield chemical agents, the performance of the biomass phenolic resin filtration loss reducer prepared in the example 4 is detected, and the results are shown in Table 1.

Example 5

Adding 270 parts by weight of cardanol, 25 parts by weight of polyethylene glycol 600, 120 parts by weight of water and 62 parts by weight of paraformaldehyde into a four-port reaction kettle with a reflux device in sequence, and stirring for 20min at the stirring speed of 260rpm to obtain a mixture 1; keeping the stirring speed at 260rpm, adding 30 parts by weight of sodium metabisulfite into the mixture 1 by 5 times, adding 6 parts by weight of sodium metabisulfite each time, and stirring for 10min to obtain a mixture 2; adding 50 parts by weight of anhydrous sodium sulfite into the mixture 2 by 5 times, adding 10 parts of anhydrous sodium sulfite each time, and stirring for 15min to obtain a mixture 3; heating the temperature to 69 ℃, reacting for 20min, then continuously heating to 102 ℃, and reacting for 60min to obtain a mixture 4; adding 146 parts by weight of water into the mixture 4 every 30min, adding 5 times of water in total, continuing to react for 70min, and discharging to obtain a biomass phenolic resin fluid loss additive liquid product.

According to the industrial standards SY/T5094-2017 filtration loss reducer sulfomethyl phenolic resin SMP for drilling fluid and SY/T6787-2010 technical requirement for environmental protection of water-soluble oilfield chemical agents, the performance of the biomass phenolic resin filtration loss reducer prepared in the example 5 is detected, and the results are shown in Table 1.

Comparative example 1

The preparation was carried out as described in example 2, except that 25 parts by weight of polyethylene glycol 600 was not added in the preparation process, unlike in example 2.

According to the industrial standards SY/T5094-2017 filtration loss additive sulfomethyl phenolic resin SMP for drilling fluid and SY/T6787-2010 technical requirement for environmental protection of water-soluble oilfield chemical agents, the performance of the biomass phenolic aldehyde resin filtration loss additive for drilling fluid prepared in the comparative example 1 is detected, and the results are shown in Table 1.

Comparative example 2

The preparation was carried out as described in example 5, except that 25 parts by weight of polyethylene glycol 600 was not added in the preparation process, unlike in example 5.

According to the industrial standards SY/T5094-2017 filtration loss additive sulfomethyl phenolic resin SMP for drilling fluid and SY/T6787-2010 technical requirement for environmental protection of water-soluble oilfield chemical agents, the performance of the biomass phenolic aldehyde resin filtration loss additive for drilling fluid prepared in the comparative example 2 is detected, and the results are shown in Table 1.

Table 1 determination of performance of fluid loss additive of biomass phenolic resin prepared in inventive example and comparative example

As can be seen from Table 1, the biomass phenolic resin fluid loss additive prepared in the embodiments 1 to 5 has the dry basis content of 31 to 35 percent, the cloud point salinity of 150 to 160g/L, the high-temperature and high-pressure fluid loss at 180 ℃ of 14 to 23mL, the apparent viscosity of 26 to 30mPa.s and the biomass toxicity EC₅₀The value of 32.0 to 48.0 x 10⁴mg/L, biodegradable BOD/COD_Cr0.31 to 0.54.

Compared with comparative example 1 and comparative example 2, the product prepared without adding polyethylene glycol 600 has the dry basis content of 31-33%, the cloud point salinity of only 102-110 g/L, the high-temperature high-pressure filtration loss at 180 ℃ of 56.6-62.4 mL, the apparent viscosity of 34-36 mPa.s and the biomass toxicity EC₅₀The value is 132000-134000 mg/L, and the biodegradability is BOD/COD_CrIs only 0.06-0.08. The comprehensive performance and the environmental protection performance of the biomass phenolic resin fluid loss agent prepared by the method are far better than those of a product prepared by a comparative example.

SMP (sulfometlbond, institute of drilling engineering technology, central oil engineering corporation,model SMP-I) environmental Performance, biodegradability BOD/COD_Cr0.0123, Biomass toxicity EC₅₀The value is 9700mg/L, which shows that the biomass phenolic resin fluid loss additive prepared by the method has excellent environmental protection performance and can replace SMP to be applied in areas with high environmental requirements.

The embodiment shows that the invention provides a biomass phenolic resin fluid loss additive with a structure shown in formula I, wherein n is 0-3, and m is 7-12. The biomass phenolic resin fluid loss agent provided by the invention is green and environment-friendly, has good fluid loss performance and strong salt resistance, and can be biodegraded. The invention also provides a preparation method and application of the biomass phenolic resin fluid loss additive. The preparation method of the biomass phenolic resin filtrate reducer provided by the invention is environment-friendly, mild and simple, and has low application cost.

While only the preferred embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.