CN106635106B

CN106635106B - Viscoelastic high-softening-point asphalt particles, and preparation method and application thereof

Info

Publication number: CN106635106B
Application number: CN201510729315.4A
Authority: CN
Inventors: 傅丽; 姚汉荣; 郭皎河; 宁爱民; 刘树华
Original assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Current assignee: Sinopec Dalian Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Priority date: 2015-11-02
Filing date: 2015-11-02
Publication date: 2020-03-17
Anticipated expiration: 2035-11-02
Also published as: CN106635106A

Abstract

The invention discloses a viscoelastic high-softening-point asphalt particle, a preparation method and an application thereof, wherein the particle size of the viscoelastic high-softening-point asphalt particle is less than or equal to 120 mu m, the viscoelastic high-softening-point asphalt particle comprises a core formed by grafting activated asphalt and a shell formed by a modifier, the core accounts for 7-9 parts by mass, and the shell accounts for 1-3 parts by mass; the grafted activated asphalt is prepared by reacting base asphalt and organic acid anhydride at the temperature of 150-250 ℃, the modifier comprises polymeric sulfur and free sulfur, and the weight ratio of the polymeric sulfur to the free sulfur in the modifier is 3: 7-7: 3. And the asphalt particles are respectively sprayed into countercurrent contact with molten grafted activated asphalt from two ends of a reaction tower after sulfur is molten and polymerized, and then sprayed into quenching liquid for quenching to obtain the asphalt. The prepared asphalt is prepared by coating a layer of high-elastic polymeric sulfur outside the grafted activated asphalt, and the obtained product has small particle size, certain elastic deformation capacity and excellent high-temperature resistance and can be stably stored at normal temperature.

Description

Viscoelastic high-softening-point asphalt particles, and preparation method and application thereof

Technical Field

The invention relates to viscoelastic high-softening-point asphalt and a preparation method thereof, in particular to high-softening-point asphalt with smaller particle size and deformability.

Background

High softening point bitumen is a bitumen having a softening point above 100 ℃, especially above 120 ℃. High softening point asphalts have been used in a wide variety of applications because of their excellent high temperature resistance. For example, as a roof covering for a building, will not become very soft or even flow even in hot summer months. The drilling fluid can also be used in the drilling operation of deep oil and gas fields, and can play a role in plugging, preventing collapse, stabilizing the well wall and reducing the rate and the filtration loss under the high-temperature condition as an important component of the drilling fluid. In addition, the polymer can be used as a modification additive for polymer materials.

The asphalt product has wide application in the oil and gas drilling process, can be used as an important component of drilling fluid (commonly called mud), is one of indispensable important agents in modern drilling engineering at home and abroad, and has good comprehensive effects of preventing collapse, lubricating, reducing filtration loss, stabilizing at high temperature and the like. With the development of petroleum exploration and development, the drilling depth is continuously deepened, the drilling of the stratum is more and more complex, and the number of special process wells such as directional wells, horizontal wells and the like is gradually increased. This makes the drilling engineering put higher demands on the bitumen products for drilling fluids and their systems. Ordinary asphalt with a softening point cannot meet the requirement of high-temperature operation under deep wells because of excessive softening and even flowing. The development of the high-softening-point asphalt with good high-temperature performance, good plugging property and fluid loss reduction property to meet the requirements of oil field drilling engineering has very important significance.

In order to improve the service performance of asphalt products for drilling fluid, a plurality of methods for modifying asphalt are successively disclosed at home and abroad. The most prominent of these is the sulfonation of asphalt. Such as US3485745, CN99109453, CN201010250241, etc. Although this method can increase the water solubility of the product, the oil solubility is low. After sulfonation, the asphalt mainly generates sulfonate, the softening point of the product can not be detected almost, and the asphalt can only be used under the condition of lower temperature. And the particles have no elasticity and poor deformation capability, and can not be randomly embedded into the pore passages in the well, particularly irregular pore passages, and can not well play the roles of plugging and reducing the fluid loss. Meanwhile, the process is complex and is easy to cause pollution to the environment.

When the high-softening-point asphalt is used in the drilling fluid, the high-softening-point asphalt is required to be dispersed into a mud system by micro particles, so that the uniform dispersion of the asphalt can be ensured, and the problems that the asphalt is agglomerated into larger blocks to block a vibrating screen to cause incapability of use and the like can be avoided. Generally, the particle size of the asphalt particles is required to be below 120 μm, even below 100 μm for normal use.

However, it is very difficult to pulverize the pitch into small particles. Stone or coal-like materials can be crushed into very small particles using conventional crushing equipment. However, bitumen is very different from the above-mentioned substances. Because a large amount of heat is generated as the pulverizer rotates at a high speed to rub against the material during the pulverizing process, the temperature of the material is increased much. Asphalt becomes soft and sticky with the rise of temperature due to its special physical properties, and even small particles that have been crushed will re-stick into larger particles. And the smaller the particle size of the pulverization, the more remarkable the case.

To solve these problems, CN95120535 discloses a process for producing fine particles of pitch having a high softening point. It mainly comprises three steps: the raw materials and water are first made into emulsion, then light components are extracted and removed from the fine particles of the emulsion, and finally the fine particles of the asphalt are separated and recovered. The method can obtain fine asphalt particles, and has the disadvantages of complicated process, large amount of organic solvent required for extraction, and high production cost. Drying is required during the final recycling process, which tends to cause the bitumen particles to partially melt and re-adhere together.

CN201110353561 discloses a method of adding a solid dispersant and a coating agent in the asphalt crushing process to solve the crushing problem of asphalt with a high softening point, and a certain effect is achieved. However, the introduced solid dispersant is an inert component and may damage the drilling fluid system to some extent. In addition, in order to ensure that the asphalt particles are not bonded again when stored at normal temperature, a coating agent needs to be added additionally, which increases the cost and complexity of the process.

Accordingly, there is a need in the art for high softening point asphalt particles that are small in particle size, do not agglomerate during storage at ambient temperatures, and have suitable variability capability.

Disclosure of Invention

Aiming at the defects that the method for preparing the high-softening-point asphalt particles meeting the use requirement of the drilling fluid in the prior art is complex in process, an organic solvent is required to be used in the preparation process, other additives for destroying a use system are required to be introduced, the asphalt particles cannot be stored at normal temperature for a long time, or the particles after being crushed are poor in deformability and the like, the invention provides the viscoelastic high-softening-point asphalt particles.

The technical purpose of the invention is realized by the following technical scheme:

the viscoelastic high-softening-point asphalt particle has a particle size of less than or equal to 120 mu m, and comprises a core formed by grafting activated asphalt and a shell formed by a modifier, wherein the core is 7-9 parts by weight, and the shell is 1-3 parts by weight;

the graft activated asphalt is prepared by reacting base asphalt with organic acid anhydride at the temperature of 150-250 ℃, wherein the organic acid anhydride is selected from at least one of maleic anhydride, polyactic anhydride, polyglutamic anhydride, polyazelaic anhydride and polyisobutylene succinic anhydride;

the modifier comprises polymeric sulfur and free sulfur, and the weight ratio of the polymeric sulfur to the free sulfur in the modifier is 3: 7-7: 3.

Further, the base asphalt is asphalt with a softening point of 100-200 ℃ and is selected from at least one of oxidized asphalt, solvent deoiled asphalt and natural asphalt.

Further, the modifier is obtained by heating sulfur to 250-350 ℃ for melting, introducing inert gas, keeping the pressure at 0.5-2.0 MPa, reacting for 10-100 minutes, and then quenching. In the process of preparing the modifier by using the sulfur, a stabilizer is also added when the sulfur is molten, wherein the stabilizer is olefin or halogenated aromatic hydrocarbon.

Further, the stabilizer is selected from at least one of 1-dodecene, 1-tetradecene, 1-octadecene, butadiene, chloroprene, isoprene, styrene, hexachloro-p-xylene, iodonitrobenzene and bromonitrobenzene; .

Another technical object of the present invention is to provide a method for preparing the above viscoelastic high softening point asphalt particles, comprising the steps of:

①, heating sulfur powder to 250-350 ℃, adding a stabilizer after 10-60 minutes, introducing inert gas, keeping the pressure at 0.5-2.0 MPa, reacting for 10-100 minutes, and melting and polymerizing sulfur to form a liquid modifier;

② heating the base asphalt to a molten state, adding organic acid anhydride accounting for 2-20% of the weight of the asphalt, and introducing inert gas to keep the pressure of an asphalt reaction kettle at 0.2-1.0MPa, the reaction temperature of 150-;

③, respectively spraying the liquid modifier in the step ① and the grafting activated asphalt reaction liquid in the step ② from two ends of the reaction tower, and keeping the liquid modifier and the grafting activated asphalt reaction liquid in countercurrent contact for 10-60 minutes according to the weight ratio of sulfur to grafting activated asphalt reaction liquid of 1-3: 7-9;

④, spraying the product obtained in the step ③ into quenching liquid at 40-65 ℃ for quenching to form modifier-coated asphalt particles, suspending the modifier-coated asphalt particles in the quenching liquid, keeping the temperature for 30-120 minutes, dehydrating and drying the modifier-coated asphalt particles, and screening the obtained solid by using a vibrating screen;

the stabilizer is olefin or halogenated aromatic hydrocarbon; the anhydride is selected from at least one of maleic anhydride, polyactic anhydride, polyglutamic anhydride, polyazelaic anhydride and polyisobutylene succinic anhydride.

Further, the stabilizer is selected from at least one of 1-dodecene, 1-tetradecene, 1-octadecene, butadiene, chloroprene, isoprene, styrene, hexachloro-p-xylene, iodonitrobenzene and bromonitrobenzene. The adding amount of the sulfur-containing additive is 0.01-0.5% of the weight of the sulfur.

Further, industrial top-grade sulfur powder (with the purity of more than 99.5%) is selected as the sulfur, and water is used as the quenching liquid.

The viscoelastic high-softening-point asphalt particles prepared by the invention have excellent high-temperature performance and certain elastic deformation capacity, are suitable for long-term storage at normal temperature (no bonding), can be used for preparing drilling fluid, and are added into the drilling fluid in an amount of 1-10%.

Compared with the prior art, the invention has the following advantages:

(1) in the preparation method, the basic asphalt is firstly subjected to grafting reaction, so that the molecular part of the asphalt is connected with acid anhydride, the surface of the asphalt has active groups, and the active groups can be combined with free radicals at two ends of the polymeric sulfur when contacting the polymeric sulfur to play a role in stabilizing and improve the yield of the high-elasticity polymeric sulfur. The high-softening-point asphalt is introduced at the later stage of sulfur melting polymerization, so that a layer of coating layer can be formed outside the asphalt by the high-elastic sulfur polymer, and an organic whole is formed after subsequent cooling and stabilizing treatment, so that the service performance of asphalt particles is improved.

(2) In the process of the present invention, an inert gas (e.g., N) is introduced during the polymerization of sulfur₂) Firstly, the protection effect is realized at high temperature, and on the other hand, enough power is provided for sulfur atomization after polymerization; in addition, the particle size of the final particles can be adjusted by adjusting the pressure, so that different use requirements can be met.

(3) Generally, after the sulfur is melted and reacted, the conversion rate of high-elasticity polymerized sulfur is 40-60%, and the method does not need to carry out extraction, purification and other treatments, because the unconverted sulfur can not form an organic whole with high-softening-point asphalt, but is a good dispersing agent and isolating agent, so that the high-softening-point particles obtained by the method can be stored for a long time at normal temperature without adding other auxiliary agents, and the production process is simplified.

(4) The method has simple process, convenient operation and lower cost, the prepared high-softening-point asphalt is a mixture of high-elasticity polymeric sulfur and free sulfur coated outside the grafted activated asphalt, and the obtained product has small particle size, certain elastic deformation capacity and excellent high-temperature resistance and can be stably stored at normal temperature.

Detailed Description

The following non-limiting examples are presented to enable those of ordinary skill in the art to more fully understand the present invention and are not intended to limit the invention in any way.

Example 1

Heating 400g of asphalt with the softening point of 123.3 ℃ to 160 ℃ in an asphalt reaction kettle, adding 12g of maleic anhydride, introducing inert gas to keep the pressure of the asphalt reaction kettle at 0.5MPa, and reacting for 3 hours to obtain grafted activated asphalt; 100g of sulfur powder is put into a closed sulfur reaction kettle, heated to 280 ℃ for 40 minutes, 0.1g of 1-dodecene is added, and N is introduced simultaneously₂The pressure was kept at 1.0 MPa. After the asphalt grafting reaction is finished, simultaneously opening a valve of the reaction kettle to perform asphalt grafting reactionThe two liquids are sprayed into the contact tower, molten sulfur enters from the upper part of the tower, and molten asphalt enters from the lower part of the tower, so that the two liquids are in full countercurrent contact and are kept for 30 minutes. And opening a discharge valve at the bottom of the contact tower, and quickly spraying the liquid into cold water for quenching to form uniform particles which are formed by integrating the asphalt and the high-elasticity sulfur and are suspended in the quenching liquid. The mixture was kept at 45 ℃ for 30 minutes, sufficiently cured and stabilized, and then dehydrated and vacuum-dried. And sieving the obtained solid by using a vibrating screen to obtain the viscoelastic high-softening-point particles.

Example 2

Heating 425g of asphalt with the softening point of 132.5 ℃ to 175 ℃ in an asphalt reaction kettle, adding 17g of polyisobutylene succinic anhydride, introducing inert gas to keep the pressure of the asphalt reaction kettle at 0.7MPa, and reacting for 4.5 hours to obtain grafted activated asphalt; 75g of sulfur powder is placed in a closed sulfur reaction kettle, heated to 300 ℃ for 50 minutes, then 0.12g of isoprene is added, and N is introduced simultaneously₂The pressure was kept at 1.5 MPa. After the asphalt grafting reaction is completed, simultaneously opening a valve of the reaction kettle, spraying the two liquids into a contact tower, feeding molten sulfur into the contact tower from the upper part of the contact tower, feeding molten asphalt into the contact tower from the lower part of the contact tower, and fully carrying out countercurrent contact on the molten sulfur and the molten asphalt for 40 minutes. And opening a discharge valve at the bottom of the contact tower, and quickly spraying the liquid into cold water for quenching to form uniform particles which are formed by integrating the asphalt and the high-elasticity sulfur and are suspended in the quenching liquid. The mixture was kept at 50 ℃ for 35 minutes, sufficiently cured and stabilized, and then dehydrated and vacuum-dried. And sieving the obtained solid by using a vibrating screen to obtain the viscoelastic high-softening-point particles.

Example 3

Heating 350g of asphalt with the softening point of 146.7 ℃ to 190 ℃ in an asphalt reaction kettle, adding 14g of polyactic anhydride, introducing inert gas to keep the pressure of the asphalt reaction kettle at 0.85MPa, and reacting for 6 hours to obtain grafted activated asphalt; 150g of sulfur powder is placed in a closed sulfur reaction kettle, heated to 320 ℃ for 55 minutes, then 0.26g of 1-octadecene is added, and N is introduced₂The pressure was kept at 1.2 MPa. After the asphalt grafting reaction is finished, simultaneously opening a valve of the reaction kettle,the two liquids were sprayed into the contactor, molten sulfur entered from the top of the tower, and molten asphalt entered from the bottom of the tower, allowing them to undergo sufficient countercurrent contact for 45 minutes. And opening a discharge valve at the bottom of the contact tower, and quickly spraying the liquid into cold water for quenching to form uniform particles which are formed by integrating the asphalt and the high-elasticity sulfur and are suspended in the quenching liquid. The mixture was kept at 55 ℃ for 40 minutes, sufficiently cured and stabilized, and then dehydrated and vacuum-dried. And sieving the obtained solid by using a vibrating screen to obtain the viscoelastic high-softening-point particles.

Example 4

Heating 375g of asphalt with the softening point of 164.2 ℃ to 210 ℃ in an asphalt reaction kettle, adding 18.75g of maleic anhydride, introducing inert gas to keep the pressure of the asphalt reaction kettle at 1.0MPa, and reacting for 5.5 hours to obtain grafted activated asphalt; 125g of sulfur powder is put into a closed sulfur reaction kettle, heated to 340 ℃, added with 0.20g of hexachloro-p-xylene after 40 minutes, and simultaneously introduced with N₂The pressure was kept at 1.6 MPa. After the asphalt grafting reaction is completed, simultaneously opening a valve of the reaction kettle, spraying the two liquids into a contact tower, feeding molten sulfur into the contact tower from the upper part of the contact tower, feeding molten asphalt into the contact tower from the lower part of the contact tower, and fully performing countercurrent contact on the molten sulfur and the molten asphalt for 50 minutes. And opening a discharge valve at the bottom of the contact tower, and quickly spraying the liquid into cold water for quenching to form uniform particles which are formed by integrating the asphalt and the high-elasticity sulfur and are suspended in the quenching liquid. The mixture is kept at 60 ℃ for 35 minutes, and sufficient solidification and stabilization are carried out, and then dehydration and vacuum drying treatment are carried out. And sieving the obtained solid by using a vibrating screen to obtain the viscoelastic high-softening-point particles.

The viscoelastic high-softening-point particles obtained in the respective examples were measured for properties such as softening point, average particle size, and after-sieve passage rate, and the results are shown in table 1.

The high-softening-point asphalt particles obtained in the above examples were placed in 400mL of prepared drilling mud (the addition amount was 3%), high-speed shearing was performed for 10 minutes, then sodium dodecyl sulfate accounting for 0.2% of the mass of the mud was added, and shearing was continued for 10 minutes to obtain a drilling fluid system, and the performance results are shown in table 2.

TABLE 1 particle Properties of the high softening Point asphalt compositions of the examples

Note: the post-screening passage rate refers to: after the particles are stacked for 30 days at normal temperature, the particles are sieved by a standard sieve with the same aperture as that of the particles just prepared, and the mass of the particles passing through the sieve pores accounts for the percentage of the total mass. The index mainly examines the stability of the particles after storage, namely the change of the particle size.

TABLE 2 Properties of the drilling fluids

Claims

1. A viscoelastic high softening point asphalt particle characterized by: the particle size of the asphalt particles is less than or equal to 120 mu m, and the asphalt particles comprise a core formed by grafting activated asphalt and a shell formed by a modifier, wherein the core accounts for 7-9 parts by mass, and the shell accounts for 1-3 parts by mass;

2. The viscoelastic high softening point asphalt granule of claim 1, characterized in that: the base asphalt is asphalt with a softening point of 100-200 ℃ and is selected from at least one of oxidized asphalt, solvent deoiled asphalt and natural asphalt.

3. The viscoelastic high softening point asphalt granule of claim 1, characterized in that: the modifier is obtained by heating sulfur to 250-350 ℃ for melting, introducing inert gas, keeping the pressure at 0.5-2.0 MPa, reacting for 10-100 minutes, and then quenching.

4. The viscoelastic high softening point asphalt granule of claim 3, characterized in that: in the process of preparing the modifier by using the sulfur, a stabilizer is also added when the sulfur is molten, wherein the stabilizer is olefin or halogenated aromatic hydrocarbon.

5. The viscoelastic high softening point asphalt granule of claim 4, characterized in that: the stabilizer is selected from at least one of 1-dodecene, 1-tetradecene, 1-octadecene, butadiene, chloroprene, isoprene, styrene, hexachloro-p-xylene, iodonitrobenzene and bromonitrobenzene.

6. A process for preparing viscoelastic high-softening-point asphalt particles according to any one of claims 1 to 5, comprising the steps of:

7. The method for producing viscoelastic high-softening-point asphalt particles according to claim 6, wherein: the stabilizer is selected from at least one of 1-dodecene, 1-tetradecene, 1-octadecene, butadiene, chloroprene, isoprene, styrene, hexachloro-p-xylene, iodonitrobenzene and bromonitrobenzene.

8. The method for producing viscoelastic high-softening-point asphalt particles according to claim 6, wherein: the addition amount of the stabilizer is 0.01-0.5% of the weight of the sulfur.

9. Use of the viscoelastic high-softening-point asphalt particles according to any one of claims 1 to 5 for preparing drilling fluids.

10. Use according to claim 9, characterized in that: the addition amount of the viscoelastic high-softening-point asphalt particles in the drilling fluid is 1-10%.