阅读说明：本技术 一种超低密度合成陶粒支撑剂及其制备方法 (Ultralow-density synthetic ceramsite proppant and preparation method thereof ) 是由 王光 赵凯 卢勇 李伟雄 于 2019-08-29 设计创作，主要内容包括：本发明属于石油、天然气和页岩气压裂开采技术领域,尤其涉及一种超低密度合成陶粒支撑剂及其制备方法。本发明采用无机非金属粉体、轻质材料以及树脂粘结剂为主要原料,通过造粒、低温养护工艺制备,并在造粒过程中分次补加无机非金属粉体。本发明的制备工艺简单,采用造粒、低温养护工艺,免去了传统烧结技术,降低能耗,节能减排。制得的支撑剂满足超低密度的要求,同时具有良好的强度,且产品的颗粒圆球度高、表面光洁度好,可降低油田开采成本。(The invention belongs to the technical field of oil, natural gas and shale air pressure fracturing mining, and particularly relates to an ultralow-density synthetic ceramsite proppant and a preparation method thereof. The invention adopts inorganic non-metal powder, light material and resin binder as main raw materials, and is prepared by granulation and low-temperature maintenance processes, and the inorganic non-metal powder is replenished in the granulation process. The preparation process is simple, granulation and low-temperature maintenance processes are adopted, the traditional sintering technology is omitted, energy consumption is reduced, and energy conservation and emission reduction are achieved. The prepared proppant meets the requirement of ultralow density, has good strength, high particle sphericity and good surface smoothness, and can reduce the oilfield exploitation cost.)

1. The ultra-low density synthetic ceramsite proppant is characterized by comprising the following raw materials in parts by weight: 100 parts of inorganic non-metal powder, 2-15 parts of light material and 8-10 parts of binder.

2. The ultra-low density synthetic ceramsite proppant according to claim 1, wherein the inorganic non-metal powder comprises one or more of quartz powder, fly ash, coal gangue powder, slag powder and stainless steel slag powder, and the sieving rate of the inorganic non-metal powder passing through a 325-mesh sieve is greater than 85%.

3. The ultra-low density synthetic ceramsite proppant according to claim 1, wherein the lightweight material is hollow glass microspheres or floating beads, and the particle size is 140-300 meshes.

4. The ultra-low density synthetic ceramsite proppant according to claim 1, wherein the binder is a phenolic resin or an epoxy resin.

5. The ultra-low density synthetic ceramsite proppant according to claim 4, wherein when the binder is epoxy resin, the raw materials further comprise a curing agent and a diluent, the curing agent accounts for 5-40 wt% of the epoxy resin, and the diluent accounts for 10-40 wt% of the epoxy resin.

6. The ultra-low density synthetic ceramsite proppant according to claim 1, wherein the particle size of said proppant is 425-850 μm.

7. The method for preparing the ultra-low density synthetic ceramsite proppant according to any one of claims 1-6, wherein the method comprises the following steps:

(1) putting inorganic non-metal powder and a light material into a mixer to be uniformly mixed, and adding the mixture into a granulator;

(2) spraying the binder into a granulator for granulation, and supplementing inorganic non-metal powder in sections in the granulation process to obtain raw material granules;

(3) and curing the raw material particles at the temperature of 80-160 ℃ for 1-6h, cooling and screening to obtain the proppant.

8. The method for preparing ultra-low density synthetic ceramsite proppant according to claim 7, wherein the inorganic non-metal powder is added in two times in step (2).

9. The preparation method of the ultra-low density synthetic ceramsite proppant according to claim 8, wherein the mass ratio of the inorganic non-metal powder added into the mixer to the inorganic non-metal powder added twice in the granulation process is (4-6):1: 1.

10. The method for preparing the ultra-low density synthetic ceramsite proppant according to claim 8, wherein 60-80min after the binder is sprayed and added, the first addition of the inorganic non-metal powder is performed; and (4) performing second replenishment of the inorganic non-metal powder 60-120min after the first replenishment is completed, and continuously stirring and granulating for 60-90min by using the granulator after the second replenishment is completed.

Technical Field

The invention belongs to the technical field of oil, natural gas and shale air pressure fracturing mining, and particularly relates to an ultralow-density synthetic ceramsite proppant and a preparation method thereof.

Background

The hydraulic fracturing is an important new technology for the production increase of low-permeability oil and gas wells of petroleum and natural gas, and the proppant is a key material for fracturing construction. When deep well fracturing construction is carried out, the propping agent is brought into and supported in fractures of a fractured stratum by the fracturing fluid, the fractures are prevented from being closed, a conduction channel is provided for oil gas seepage, the flow conductivity of the stratum can be increased, the oil gas yield is improved, the service life of an oil well is prolonged, and the method is an important factor for the application of a fracturing process.

The fracturing propping agents commonly used at present comprise quartz sand, ceramsite and the like. The quartz sand has low relative density, is convenient for construction and pumping, but has low strength, poor sphericity and high breakage rate, and reduces the flow conductivity of cracks; the sphericity, the crushing resistance and the flow conductivity of the ceramsite proppant are better than those of quartz sand, but the density of the ceramsite proppant is higher than that of the quartz sand, so that higher requirements are provided for pumping conditions and the performance of fracturing fluid, and the construction difficulty is increased. The ultra-low density proppant is increasingly widely used due to the advantages of easy carrying, capability of greatly reducing the viscosity of the fracturing fluid, reduction of damage to fracturing equipment and the like.

At present, the ultra-low density proppant is divided into an inorganic type, an organic type and a composite type. Wherein the inorganic type is mainly finished by granulation and sintering, and the energy consumption is high; the organic type is mainly made of high polymer materials, and a large amount of resin materials are consumed; the composite preparation method comprises the steps of granulation, sintering, film coating or granulation and film coating, the problems of complex processing and uncontrollable quality exist in both methods, and meanwhile, a large amount of energy consumption is needed in the calcination process, so that the energy conservation and emission reduction are not facilitated. For example, the Chinese patent with publication number CN105131933A discloses an ultra-low density ceramic proppant and a preparation method thereof, and the preparation process also comprises the steps of drying and sintering after granulation is finished, wherein the sintering temperature is 1250 ℃, the sintering temperature is high, and the energy consumption is high.

Disclosure of Invention

Aiming at the technical problems, the invention provides an ultralow-density synthetic ceramsite proppant and a preparation method thereof, which realize controllable density, simplify the production process by adopting a one-step forming technology, and realize energy conservation and emission reduction by low-temperature curing.

The invention adopts the following technical scheme:

an ultra-low density synthetic ceramsite proppant comprises the following raw materials in parts by weight: 100 parts of inorganic non-metal powder, 2-15 parts of light material and 8-10 parts of binder.

Further, the inorganic non-metal powder comprises one or more of quartz powder, fly ash, coal gangue powder, slag powder and stainless steel slag powder, and the sieving rate of the inorganic non-metal powder passing through a 325-mesh sieve is more than 85%.

Furthermore, the light material is hollow glass beads or floating beads, and the particle size is 140-300 meshes. The light material mainly plays a role in reducing the density of proppant particles, and meanwhile, compared with other light materials, the hollow glass beads and the floating beads in the invention have excellent effects of high strength, low density, acid and alkali resistance and the like. The light material is added as a raw material in the granulation process, the particle size is 140-300 meshes, and if the particle size is too large, the particle size of the proppant particles is large and cannot reach the particle size of the proppant common specification; if the particle size is too small, the density increases significantly, and the effect of controlling the density cannot be achieved.

Further, the binder is phenolic resin or epoxy resin. More specifically, the phenolic resin is thermosetting phenolic resin with the viscosity of 10-10000 mPas; the epoxy value of the epoxy resin is 0.42 to 0.55. The viscosity of the adhesive is further controlled by controlling the viscosity of the phenolic resin and the epoxy value of the epoxy resin, so that the phenomenon that the adhesive is too high in viscosity and difficult to granulate is prevented, and the yield of the proppant is reduced.

Preferably, the raw material of the invention also comprises a coupling agent, wherein the coupling agent is one or more of silane coupling agents KH550, KH560 and KH570, and the content of the coupling agent is 5-10 wt% of the binder.

Furthermore, when the adhesive is epoxy resin, the raw materials also comprise a curing agent and a diluent, wherein the content of the curing agent is 5-40 wt% of the epoxy resin, and the content of the diluent is 10-40 wt% of the epoxy resin. Specifically, the curing agent is one or more of aromatic amine curing agent, anhydride curing agent, dicyandiamide curing agent and imidazole curing agent; the diluent is an epoxy reactive diluent.

Further, the particle size of the proppant was 425 and 850 μm.

The ultra-low density synthetic ceramsite proppant disclosed by the invention can realize the control of the density of the proppant by adjusting the content of the light material in the raw material, and the apparent density of the composite proppant disclosed by the invention is 1.85-2.15g/cm³The bulk density is 0.9-1.15g/cm³The ultra-low density composite material meets the requirement of ultra-low density, has good strength, has the breakage rate of 69MPa below 8.5 percent, has high particle sphericity and good surface smoothness, and can reduce the exploitation cost of oil fields.

The invention also provides a preparation method of the ultralow-density synthetic ceramsite proppant, which comprises the following steps:

(1) putting inorganic non-metal powder and a light material into a mixer to be uniformly mixed, and adding the mixture into a granulator;

(2) spraying the binder into a granulator for granulation, and supplementing inorganic non-metal powder in sections in the granulation process to obtain raw material granules;

(3) and curing the raw material particles at the temperature of 80-160 ℃ for 1-6h, cooling and screening to obtain the proppant.

Further, in the step (2), the inorganic non-metal powder is supplemented twice.

Furthermore, the mass ratio of the inorganic non-metal powder added in the mixer to the inorganic non-metal powder replenished twice in the granulation process is (4-6):1: 1.

Further, 60-80min after the binder is sprayed and added, the first supplement of the inorganic non-metal powder is carried out; and (4) performing second replenishment of the inorganic non-metal powder 60-120min after the first replenishment is completed, and continuously stirring and granulating for 60-90min by using the granulator after the second replenishment is completed.

The preparation method of the ultralow-density synthetic ceramsite proppant disclosed by the invention is prepared by adopting granulation and low-temperature maintenance processes, resin is used as a binder, an inorganic non-metallic material is used as a filler for granulation, the resin can be solidified at a temperature of less than 200 ℃, and the ultralow-density synthetic ceramsite proppant has good mechanical strength, avoids the traditional sintering technology, reduces energy consumption, saves energy and reduces emission. Meanwhile, the inorganic non-metal powder is added for many times in the middle and later stages of granulation, so that the dispersion of particles in the granulation process is realized, the excessive bonding is prevented, the sphericity of raw material particles is favorably adjusted by adding for many times in stages, the finished product rate of the proppant is improved, and the finished product rate of the proppant is over 80 percent.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to specific embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The preparation method of the ultra-low density synthetic ceramsite proppant comprises the following steps:

(1) putting inorganic non-metal powder and a light material into a mixer to be uniformly mixed, and adding the mixture into a granulator; if the binder is epoxy resin, the method also comprises the steps of putting a curing agent into a mixer for mixing, and mixing the epoxy resin with diluent liquid;

(2) spraying the binder into a granulator for granulation, and supplementing inorganic non-metal powder in sections in the granulation process to obtain raw material granules;

(3) and curing the raw material particles at the temperature of 80-160 ℃ for 1-6h, cooling and screening to obtain the proppant.

Preferably, the granulator is a disk granulator or a round pan granulator. The rotating speed of the granulator is 15-50 r/min.

Specifically, in the step (2), the inorganic non-metal powder is supplemented twice. 60-80min after the binder is sprayed and added, and performing first supplement of inorganic non-metal powder; after the first supplementing is finished, performing second supplementing of the inorganic non-metal powder 60-120 min; and after the second supplement is finished, the granulator is continuously stirred for granulation for 60-90 min. The inorganic non-metal powder is added after the binder is added for a period of time, the binder plays a certain binding role, the agglomeration and granulation effects among the raw materials are obvious, the inorganic non-metal powder with the dispersion effect is added, the particles with larger agglomeration are favorably dispersed, the secondary staged addition is adopted, the control on the particle size and the sphericity of the raw material particles is favorably realized, the requirements on the particle size and the sphericity of finished product particles are met, and the yield is improved. If the time for adding the inorganic non-metal powder is too early, the binder does not fully function at this time, and the granulation cannot be easily caused.

Specifically, the mass ratio of the inorganic non-metal powder added in the mixer to the inorganic non-metal powder added twice in the granulation process is (4-6):1: 1.

The ultra-low density synthetic ceramsite proppant and the preparation method thereof according to the present invention will be further described with reference to the following specific examples.

Example 1

A preparation method of an ultra-low density synthetic ceramsite proppant comprises the following steps:

(1) 190g of 128 epoxy resin and 70g of AGE epoxy resin reactive diluent are uniformly mixed for later use, 1700g of quartz powder, 50g of floating beads and 65g of diaminodiphenylmethane are uniformly mixed and then are added into a disc granulator;

(2) spraying the mixed solution of the epoxy resin and the diluent into a granulator for granulation, adding 300g of quartz powder after the mixed solution is added for 60min, continuously operating the granulator for 60min, then adding 300g of quartz powder, and continuously operating for 60min to obtain raw material granules;

(3) curing the raw material particles for 4h at 160 ℃, cooling and screening to obtain the proppant with the particle size of 425 and 850 mu m, wherein the yield is 90%.

The proppant obtained in the example was tested according to SY/T5108-2014 proppant Performance test method for Hydraulic fracturing and gravel packing operations, and the proppant obtained in the example had a sphericity of 0.95, a turbidity of 25FTU, and a bulk density of 1.15g/cm³Apparent density 2.15g/cm³And the breaking rate of 69MPa is 2.56 percent.

Example 2

A preparation method of an ultra-low density synthetic ceramsite proppant comprises the following steps:

(1) uniformly mixing 200g of 128 epoxy resin and 70g of 692 epoxy resin reactive diluent for later use, uniformly mixing 1700g of fly ash, 100g of hollow glass microsphere and 65g of diaminodiphenylmethane, and adding the mixture into a round pot granulator;

(2) spraying the mixed solution of the epoxy resin and the diluent into a granulator for granulation, adding 300g of fly ash 60min after the mixed solution is added, continuously operating the granulator for 120min, then adding 300g of fly ash, and continuously operating for 90min to obtain raw material granules;

(3) curing the raw material particles at 80 ℃ for 6h, cooling and screening to obtain the proppant with the particle size of 425 and 850 mu m, wherein the yield is 88.5%.

The proppant obtained in the example was tested according to SY/T5108-2014 proppant Performance test method for Hydraulic fracturing and gravel packing operations, and the proppant obtained in the example had a sphericity of 0.95, a turbidity of 20FTU, and a bulk density of 1.08g/cm³Apparent density of 2.03g/cm³And the breaking rate is 5.33 percent at 69 MPa.

Example 3

A preparation method of an ultra-low density synthetic ceramsite proppant comprises the following steps:

(1) 190g of 128 epoxy resin and 70g of AGE epoxy resin reactive diluent are uniformly mixed for later use, 1400g of quartz powder, 300g of floating beads and 65g of diaminodiphenylmethane are uniformly mixed and then are added into a round pot granulator;

(2) spraying the mixed solution of the epoxy resin and the diluent into a granulator for granulation, adding 300g of quartz powder after the mixed solution is added for 80min, continuously operating the granulator for 60min, then adding 300g of quartz powder, and continuously operating for 60min to obtain raw material granules;

(3) curing the raw material particles for 2h at 100 ℃, cooling and screening to obtain the proppant with the particle size of 425 and 850 mu m, wherein the yield is 83.8%.

The proppant obtained in this example was tested according to SY/T5108-2014 proppant Performance test method for Hydraulic fracturing and gravel packing operations to obtain the proppant of this example with sphericity of 0.95, turbidity of 23FTU, and bulk density of 0.93g/cm³Apparent density of 1.85g/cm³And the breaking rate is 8.33 percent at 69 MPa.

Example 4

A preparation method of an ultra-low density synthetic ceramsite proppant comprises the following steps:

(1) 190g of 128 epoxy resin and 70g of AGE epoxy resin reactive diluent are uniformly mixed for later use, 1700g of quartz powder, 100g of floating bead, 50g of diaminodiphenylmethane and 10g of imidazole are uniformly mixed and then are added into a round pot granulator;

(2) spraying the mixed solution of the epoxy resin and the diluent into a granulator for granulation, adding 300g of quartz powder after the mixed solution is added for 60min, continuously operating the granulator for 120min, then adding 300g of quartz powder, and continuously operating for 60min to obtain raw material granules;

(3) curing the raw material particles for 2h at 100 ℃, cooling and screening to obtain the proppant with the particle size of 425 and 850 mu m, wherein the yield is 85.3%.

The proppant obtained in the example was tested according to SY/T5108-2014 proppant Performance test method for Hydraulic fracturing and gravel packing operations, and the proppant obtained in the example had a sphericity of 0.95, a turbidity of 15FTU, and a bulk density of 1.12g/cm³Apparent density 2.13g/cm³And the breaking rate is 5.32 percent at 69 MPa.

Example 5

A preparation method of an ultra-low density synthetic ceramsite proppant comprises the following steps:

(1) 1700g of quartz powder and 100g of floating beads are uniformly mixed and then added into a round pot granulator;

(2) spraying 400g of phenolic resin solution into a granulator for granulation, adding 300g of quartz powder after 60min of the addition of the mixed solution, continuously operating the granulator for 120min, then adding 300g of quartz powder, and continuously operating for 60min to obtain raw material granules;

(3) curing the raw material particles for 2h at 100 ℃, cooling and screening to obtain the proppant with the particle size of 425 and 850 mu m, wherein the yield is 88.2%.

The proppant obtained in the example was tested according to SY/T5108-2014 proppant Performance test method for Hydraulic fracturing and gravel packing operations, and the proppant obtained in the example had a sphericity of 0.95, a turbidity of 18FTU, and a bulk density of 1.10g/cm³Apparent density 2.08g/cm³And the breaking rate is 7.53 percent at 69 MPa.

Example 6

A preparation method of an ultra-low density synthetic ceramsite proppant comprises the following steps:

(1) 1400g of quartz powder and 200g of floating beads are uniformly mixed and then added into a round pot granulator;

(2) spraying 250g of phenolic resin solution into a granulator for granulation, adding 300g of quartz powder after 60min of the addition of the mixed solution, continuously operating the granulator for 120min, then adding 300g of quartz powder, and continuously operating for 60min to obtain raw material granules;

(3) curing the raw material particles for 2h at 100 ℃, cooling and screening to obtain the proppant with the particle size of 425 and 850 mu m, wherein the yield is 81.9%.

The proppant obtained in this example was tested according to SY/T5108-2014 proppant Performance test method for Hydraulic fracturing and gravel packing operations to obtain the proppant of this example with sphericity of 0.95, turbidity of 21FTU, and bulk density of 1.01g/cm³Apparent density of 1.98g/cm³And the breaking rate is 6.45 percent at 69 MPa.

Comparative example 1

A preparation method of an ultra-low density synthetic ceramsite proppant comprises the following steps:

(1) 190g of 128 epoxy resin and 70g of AGE epoxy resin reactive diluent are uniformly mixed for later use, 2300g of quartz powder, 50g of floating beads and 65g of diaminodiphenylmethane are uniformly mixed and then are added into a disc granulator;

(2) spraying the mixed solution of the epoxy resin and the diluent into a granulator for granulation, and operating the granulator for 180min after the mixed solution is added to obtain raw material granules;

(3) curing the raw material particles for 4h at 160 ℃, cooling and screening to obtain the proppant with the particle size of 425 and 850 mu m, wherein the yield is 60.3%.

The proppant obtained in the example was tested according to SY/T5108-2014 proppant Performance test method for Hydraulic fracturing and gravel packing operations, and the proppant obtained in the example had a sphericity of 0.6, a turbidity of 30FTU, and a bulk density of 1.1g/cm³Apparent density 2.08g/cm³And the breaking rate of 69MPa is 2.56 percent.

Comparative example 2

A preparation method of an ultra-low density synthetic ceramsite proppant comprises the following steps:

(1) 190g of 128 epoxy resin and 70g of AGE epoxy resin reactive diluent are uniformly mixed for later use, 1700g of quartz powder, 50g of floating beads and 65g of diaminodiphenylmethane are uniformly mixed and then are added into a disc granulator;

(2) spraying the mixed solution of the epoxy resin and the diluent into a granulator for granulation, adding 600g of quartz powder after the mixed solution is added for 60min, and continuously operating the granulator for 120min to obtain raw material granules;

(3) curing the raw material particles for 4h at 160 ℃, cooling and screening to obtain the proppant with the particle size of 425 and 850 mu m, wherein the yield is 68.5%.

The proppant obtained in this example was tested according to SY/T5108-2014 proppant Performance test method for Hydraulic fracturing and gravel packing operations to obtain the proppant of this example with sphericity of 0.8, turbidity of 37FTU, and bulk density of 1.1g/cm³Apparent density 2.1g/cm³And the breaking rate of 69MPa is 2.5 percent.

As can be seen from the above, the apparent density of the proppant obtained by the raw material and the preparation method of the invention is 1.85-2.15g/cm³The bulk density is 0.9-1.15g/cm³The ultra-low density composite material meets the requirement of ultra-low density, has good strength, has the breakage rate of 69MPa below 8.5 percent, has high particle sphericity and good surface smoothness, and can reduce the exploitation cost of oil fields. Meanwhile, the preparation method adopts granulation one-step forming and low-temperature curing processes, resin is used as a binder, and inorganic non-metal powder is used as a filler for granulation, so that the traditional sintering technology is changed, the proppant can be prepared by curing at the temperature lower than 200 ℃, meanwhile, the mode of supplementing the inorganic non-metal powder for many times in the later stage of granulation is adopted, the finished product ratio of the proppant is improved, and the performance indexes of the obtained proppant meet the SY/T5108-2014 technical standard.

The present invention has been further described with reference to specific embodiments, but it should be understood that the detailed description should not be construed as limiting the spirit and scope of the present invention, and various modifications made to the above-described embodiments by those of ordinary skill in the art after reading this specification are within the scope of the present invention.