Technical specification of SDKX-5000WY series composite fiber temporary plugging agent for fracturing
1. SDKX-5000WY temporary plugging agent
In order to make oil wells have been exploited for many years, new acid fracturing technology, new technology, new products and improved oil recovery Let the crude oil originally enclosed in the reservoir be a radiation channel. By adding a multi-level SDKX-5000WY temporary plugging agent function, the temporary plugging and turning form a new oil outlet channel. The method commonly used at home and abroad is the fracturing turning method. In order to achieve sufficient pressure, a fiber composite temporary plugging agent must be used to temporarily block all the original gaps, cracks, and oil passages, and new gaps, cracks and oil passages are formed after pressure is applied by water pressure, which requires The plugging agent must not only have considerable pressure and support capacity, but also have the ability to be removed. However, it is difficult to remove the plugging agent manually and mechanically in places several kilometers underground, so the plugging agent must be water Special fiber temporary plugging agents that are soluble or oil-soluble. Because the geological structure of oil wells in various regions is very different, some areas use oil-soluble temporary plugging agents (such as Changqing Oilfield, Qinghai Oilfield in Northwest China, Karamay Oilfield in Xinjiang) , Foreign countries in the Middle East, etc.), but in some areas only water-soluble temporary plugging agents (such as China’s Daqing Oilfield, Huabei Oilfield, etc.).
At present, temporary plugging agent manufacturers divide temporary plugging agents into two categories: water-soluble temporary plugging agents and oil-soluble temporary plugging agents. Our company can produce all series of temporary plugging agents from water-soluble to oil-soluble "SDKX--5000WY series" Temporary fracturing plugging agent".
Its structural characteristics are: there are two materials with alternating multilayer laminated layers in the temporary plugging agent material, one is a water-soluble layer (A material layer), the other is an oil-soluble layer (B material layer), composed of two materials Alternate multi-layer stacks form temporary plugging agent particles. Figure 1. It is a microscopic schematic diagram of alternating multi-layer stacks of intermediate temporary plugging agent.

Figure 1. Microscopic schematic diagram of alternate multi-layer stacks of temporary plugging agent
Note: AB-AB...in the figure alternate stacks.
Spherical temporary plugging agent particles are obtained by hot pressing with forming equipment. Figure 2. The left picture is the product photo of SDKX-5000XY type temporary plugging agent granules, and the right picture is the product photo of the packaged product.

Figure 2. SDKX-5000XY type temporary plugging agent granular product and packaged product photos.
Its application characteristics are:
1. In Northwest and other regions, according to user requirements, we produce partial oil-soluble temporary plugging agent, the main product is SDKX- -5000Y-O type fracturing temporary plugging agent;
2. According to user requirements in Northeast and other regions, we produce partial water-soluble temporary plugging agent, the main product is SDKX-5000Y-W type fracturing temporary plugging agent.
Its main performance characteristics are:
1. Oil-soluble temporary plugging agent, the main product is SDKX-5000Y-O type oil-soluble temporary plugging agent, which can be dissolved in 50-160℃ crude oil (the specific temperature range is set according to the oil well temperature ), dissolving time 60-180 minutes, compressive strength: 45Mpa or more;
2. Water-soluble temporary plugging agent, the main product is SDKX--5000Y-W type water-soluble temporary plugging agent, which can dissolve 90- in 50-160℃ water 95% (the specific temperature range is set according to the temperature of the oil well), the dissolution time is 60-180 minutes, and the remaining 5-10% of the layer B material will float on the water surface in an emulsion state and will not block the equipment. If there is an oil layer on the water The residue of this emulsion is also completely dissolved, and the compressive strength is above 45Mpa.
3. The outstanding advantage is: because of the existence of the laminated structure, it not only has a high compressive strength of more than 45Mpa in the dry solid state of normal temperature and pressure, but also maintains high compressive strength in the oil well reservoir; this is a general temporary plugging The general temporary plugging agents, especially the water-soluble temporary plugging agents, which are difficult to achieve, although they have high strength in the dry solid state of normal temperature and pressure, they will It becomes soft in water above 45℃, loses its compression resistance, and loses the ability of temporary blocking and diverting agent.
1.2 Introduction and classification of
SDKX-5000XY fracturing temporary plugging agent 1.2.1 Introduction of SDKX-5000XY fracturing temporary plugging agent
The SDKX-5000XY series fracturing temporary plugging agent is based on the oil field geology of Northwest China, Qinghai area and Daqing area in conjunction with the national key laboratory and provincial key laboratory of two famous geological and petroleum universities in China. The material science research and development team has successfully developed standardized high-tech products, and relies on professional forming and processing units for standardized production and inspection. It can adjust the components and processing methods according to the oil well conditions to meet the user's performance requirements:
1. Ability to adjust AB The ratio of the layer and the amount of crosslinking agent meet the choice of water-soluble or oil-soluble temporary plugging agent. When the ratio of AB layer is in the range of 1:1-1:8, it belongs to the partial oil-soluble temporary plugging agent, namely SDKX--5000Y -O type fracturing temporary plugging agent; when the AB layer ratio is listed in the range of 9:1-9.5:1, the temporary plugging agent is a water-soluble temporary plugging agent, namely SDKX-5000Y-W type fracturing temporary plugging agent.
2. The dissolution temperature can be adjusted through the component ratio and the cross-linking dosage to meet the needs of the temporary plugging agent for various temperature conditions.
3. The compressive strength can be adjusted through the composition ratio and processing technology to meet the compressive strength requirements of the temporary plugging agent.
1.2.2 The soluble principle of SDKX-5000XY type fracturing temporary plugging agent
1.2.2.1 The soluble principle of oil-soluble SDKX-5000XY-O type temporary plugging agent
adjusts the ratio of AB layer and the amount of crosslinking agent, when the ratio of AB layer Listed in the range of 1:1-1:8, it belongs to the oil-soluble temporary plugging agent, that is, the SDKX-5000XY-O type fracturing temporary plugging agent. It does not dissolve in pure water at normal temperature and oil well temperature, but dissolves in oil Preserved water, oil and water mixture (emulsion) or oil.
According to the construction technology of fracturing temporary plugging, the conditions of the oil well construction process are as follows: (1) water and oil coexist; (2) the temporary plugging agent will withstand a pressure of tens of MPa; (3) due to intermittent application of water pressure, It is equivalent to agitating. According to such conditions, we designed the temporary plugging agent to have such a microstructure: alternately stacked microstructures.
The alternate layered microstructure means: the temporary plugging agent consists of two parts of materials, one is the oil-soluble layer (A layer), and the other is the water-soluble layer (B layer), belonging to AB-AB-AB... Layered alternate coating structure, the microscopic morphology is similar to the "onion structure", and the thickness of each alternate layer is micron level. During the construction process, this temporary plugging agent does not dissolve in a single water. It can only be dissolved when there is oil and the temperature of the oil reaches the application temperature of the corresponding temporary plugging agent. When layer A is dissolved by oil, The B layer can be dissolved by water, the layers are peeled off and dissolved alternately, softened at a certain temperature (the temperature range is determined by the product model), and all dissolved within 60-180 minutes after softening.
1.2.2.2 Water-soluble SDKX--5000XY-W type temporary plugging agent can
adjust the ratio of AB layer and the amount of crosslinking agent based on the soluble principle . When the ratio of AB layer is in the range of 9:1-9.5:1, it belongs to water-soluble temporary plugging. Agent, namely SDKX-5000XY-W type fracturing temporary plugging agent, it is insoluble in water at room temperature, and at a certain temperature downhole, 90-95% of the water-soluble material in layer A swells first to expand the distance between layers Then dissolve in 50-180℃ water (the specific temperature range is set according to the oil well temperature), the dissolution time is 60-180 minutes, and the remaining 5-10% of the B layer material will float on the water surface in an emulsion state without blocking the equipment. When there is an oil layer on the water, the emulsion residue is completely dissolved.
1.2.2.3 The principle of adjusting the strength of alternately laminated microstructures
Generally, the water-soluble temporary plugging agent has high strength on the surface, but before fracturing, it will soften in the water above 45℃, lose its compressive performance, and lose the ability of temporary plugging and diverting agent. It is a common disadvantage of water-soluble temporary plugging agents made of bone glue, gelatin, soluble starch and low-temperature paraffin at present, and the price is very high.
In addition to the water-soluble A-layer material, the alternately laminated microstructure also contains the B-layer material as the final strength support. The alternately laminated microstructure forms an "arched" support to ensure the final strength of the temporary plugging agent during use to complete Realization of the fracturing process. The compressive strength of the temporary plugging agent is adjusted and controlled by the amount of B-layer material, the amount of crosslinking agent and processing conditions in the manufacturing process.
1.2.2.4 The dissolution temperature-time control principle of the temporary plugging agent
(1) The main components of the SDKX-5000XY type fracturing temporary plugging agent are: 17%-53% sodium oxalate, 17%-53% ammonium chloride, 25% -29% phenolic resin, 1%-5% hexamethylenetetramine.
(2) The role of each component: phenolic resin is the main source of strength; hexamethylenetetramine is the molding curing agent in the production process; sodium oxalate and ammonium chloride are fusion agents and densifiers, which play a role in the production process. The effect of making the temporary plugging agent complete and strengthening the strength; phenolic resin and hexamethylenetetramine form the B layer (oil-soluble layer) of the material at the manufacturing temperature; sodium oxalate and ammonium chloride are shared with the partially penetrated phenolic resin The A layer of the material (which can be completely dissolved by water).
The dissolution temperature and dissolution time of the temporary plugging agent are mainly adjusted by the amount of hexamethylenetetramine in the composition. In the range of 50℃-130℃, generally with the increase of hexamethylenetetramine in the phenolic resin, The temperature at which the temporary plugging agent dissolves will increase. On the contrary, the oil soluble temperature decreases with the decrease of hexamethylenetetramine.
The study found that in the presence of sodium oxalate and ammonium chloride, when hexamethylenetetramine accounts for 1% of the total material, the dissolution temperature of the temporary plugging agent in the crude oil containing water is about 50℃, and the total temperature is about 50℃ in 1.5-3 hours. When dissolving, for every 0.5% increase of hexamethylenetetramine, the dissolution temperature of the temporary plugging agent increases by about 10℃. The relationship between the dissolution temperature of the temporary plugging agent and the dosage of hexamethylenetetramine is shown in Table 01.
Table 01 The relationship between dissolution temperature and dissolution time and the dosage of hexamethylenetetramine

Special instructions:
1. The dissolution temperature is also related to the dissolution time. When the temperature is lower than the calculated value, it can be dissolved in a longer time. For example, TPA80 fracturing temporary plugging agent, although theoretically needs 80 ℃ to dissolve, But in fact, it can be dissolved at 55-60℃, but the dissolution time is longer, usually 2 hours.
2. For the temporary plugging agent resistant to 180℃, the situation is quite special. It is mainly used to block the tube orifice plate of natural gas fields. In principle, its temperature control is more complicated, except for the amount of hexamethylenetetramine It is also related to the amount of phenolic resin and other components. When the gas field is used, it is necessary to use oil to remove the blockage. The principle is not explained in detail here.
(3) The relationship between curing reaction and dissolution temperature:
phenolic resin synthesis reaction equation:

phenolic resin and hexamethylenetetramine are cured at a certain temperature to form a three-dimensional network structure material. This solid material has high strength (above 100 MPa) ), but the brittleness is greater. After adding other ingredients, it will be improved to become a temporary plugging agent material with sufficient strength and toughness. When the content of the added curing agent hexamethylenetetramine is sufficient, it can be cured quickly, but there is Sodium oxalate and ammonium chloride are inhibited in the presence of sodium oxalate and ammonium chloride, and the curing reaction does not completely form a three-dimensional network structure. Because adjusting the amount of hexamethylenetetramine can control the ratio of the three-dimensional network structure, adjusting the dissolution temperature is actually adjusting six times The amount of methyl tetraamine, the higher the content of hexamethylene tetramine, the more the three-dimensional network structure, the higher the temperature that needs to disassemble the three-dimensional network structure, and vice versa.
1.2.3 Classification of SDKX-5000XY type fracturing temporary plugging agent
As mentioned above, our temporary plugging agent is divided into two categories: oil-soluble SDKX-5000XY-O series and water-soluble SDKX-5000Y-W series Under these two types of tree systems, they are divided into different temperature subdivision types according to different dissolution temperatures.
1.2.3.1 Oil-soluble temporary plugging agent SDKX--5000XY type fracturing temporary plugging agent is a series of product classifications, and the type selection is based on the temperature of the oil well:
(1) SDKX-5000XY type fracturing temporary plugging agent:
suitable for oil wells (shallow oil wells) with an oil well temperature of 50℃-65℃;
(2) SDKX-5000XY-O2 type fracturing temporary plugging agent:
suitable for oil wells Oil wells with a temperature of 60℃-80℃; (deep oil wells)
(3)SDKX-5000XY type fracturing temporary plugging agent:
suitable for oil wells with a temperature of 80℃-180℃. (Deep oil wells and gas field pipe joints)
After construction, the SDKX-5000XY pressure temporary plugging agent can be dissolved in the mixture of oil and water within the corresponding temperature range. The temperature under the oil well is generally 60-120℃. The temperature range can automatically remove the blocking agent and completely dissolve and remove the temporary blocking agent. The original voids and cracks are temporarily sealed, and new cracks are fractured in a direction different from the original cracks.
1.2.3.2 Water-soluble temporary plugging agent SDKX-5000XY type fracturing temporary plugging agent is a series of product categories, and the type is selected according to the temperature of the oil well:
(1) SDKX-5000XY fracturing temporary plugging agent:
suitable for oil well temperature 50-65℃ oil well (shallow oil well);
(2)SDKX-5000XY type fracturing temporary plugging agent:
suitable for oil wells with oil well temperature 60-80℃; (deep oil well)
(3)SDKX-5000XY type Temporary cracking plugging agent:
suitable for oil wells whose temperature is 80-180℃. (Deep oil wells and gas field pipe joints)
After construction, the SDKX-5000XY pressure temporary plugging agent can be dissolved in water within the corresponding temperature range. The temperature below the oil well is generally 60-160℃. It can automatically remove the plugging agent and make the temporary plugging agent complete in the oil field temperature range. Dissolve and remove. The original voids and cracks are temporarily sealed, and new cracks are fractured in a direction different from the original cracks.

1. Product Specifications:

(1) SDKX-5000XY type fracturing temporary plugging agent softening temperature range: 50-80℃
due to the fundamental difference in structure and working principle with traditional oil-soluble temporary plugging agent, SDKX-5000XY type fracturing temporary plugging agent With alternate layered structure and dissolution method, there is no fixed "softening point", only a softening temperature range.
(2) Compressive strength: 45-90 Mpa (compressive strength sequence: TPA50 type (3) Dissolution rate (crude oil or water): 85%～100%
(4) Temporary plugging rate: 95%～100%
(5) Permeation recovery rate: 96%～100%
(6) Appearance: spherical, fiber type .
(7) Granularity: 1.5-5.5mm, with an average granularity of 1.33 mm.
(8) Particle density: 1.12-1.46g/cm3.
3. The operating procedures for product quality inspection
SDKX--5000XY type fracturing temporary plugging agent is fundamentally different from the traditional fracturing temporary plugging agent in terms of structure and principle. It has been gradually promoted in the northwest and northeast regions, and the user’s response It is satisfactory in terms of pressure or fracturing success rate. In order to facilitate the user to have a substantial understanding of the product before using the product, the operating procedures for testing the product are described based on the particularity of the product's microstructure.

3.1. The operating procedures of the oil-soluble temporary plugging agent SDKX-5000XY are as follows:
Equipment: (1) Constant temperature water bath (Figure 1.); (2) Stirrer: Laboratory electric stirrer (Figure 2.): (3) Thermometer ：0-200℃
Specific procedures:
(1) Heat the water bath to the temperature to be tested for constant temperature;
(2) Take a 1000 ml beaker, add 500 ml of kerosene (crude oil is more real) and 50-100 ml of water (oil-to-water ratio 10:1 to 5:1), the reason is: the oil and water exist at the same time during the real construction;
(3) Stirring Insert the stirrer into the beaker, slowly turn on the stirrer, and it can be turned to simulate the turbulent state of the oil field;
(4) Fix the thermometer in the kerosene (or crude oil)-water mixture in the beaker, and the temperature displayed by the thermometer is Real thermometer (temperature control temperature is only for reference, not accurate);
(5) Take 1-5 grams of temporary plugging agent, add it to the kerosene-water mixture in the beaker, and start timing at the set temperature.
Note: 1. Stirring is very important, because oil is lighter than water. If you don’t stir, the temporary plugging agent can only touch the water after sinking to the bottom, not kerosene (lost the effect of oil solubility), and the stirring imitates the actual turbulent state ; 2. Must be constant temperature, because the downhole temperature is constant. 3. Temporary plugging agent should not be too much, because the amount of oil-water flowing down the well is very large, while the laboratory oil-water is quantitative.
The experimental results should be:
(1) SDKX--5000XY; Type 50 temporary pressure plugging agent: softened in the range of 50-65°C \ 1.5 hours to dissolve, and finally add 100 water to completely transparently dissolve at the corresponding temperature;
(2) SDKX-- 5000XY; 80-type fracturing temporary plugging agent: the range of 60-80℃ is softened and can be dissolved in 1-1.5 hours, and finally 100 water is added to the corresponding temperature to completely transparently dissolve;
(3) SDKX--5000XY; 130-type fracturing temporary plugging Agent: 80-130℃ range softened \ 0.5-1.0 hours can be dissolved, and finally add 100 water in the thermostat; the corresponding temperature is completely transparent and dissolved. 
3.2. The test operation procedure of the water-soluble temporary plugging agent SDKX-5000XY is as follows:
(1) Heat the water bath to the temperature that needs to be tested for constant temperature;
(2) Take a 1000 ml beaker and add 500 ml of water;
(3) Insert the stirring of the stirrer into the beaker, slowly turn on the stirrer, and it will be able to rotate to simulate the turbulent state of the oil field;
(4) Fix the thermometer on In the beaker of water, the temperature displayed by the thermometer is the real thermometer (temperature control temperature is only for reference, not accurate);
(5) Take 1-5 grams of temporary plugging agent, add it to the beaker of water, and start timing at the set temperature.
Note: 1. Stirring is very important, it imitates the actual turbulent state; 2. It must be constant temperature, because the downhole temperature is constant. 3. Temporary plugging agent should not be too much, because the amount of oil-water flowing down the well is very large, while laboratory water is quantitative.
The experimental results should be:
(1) SDKX--5000XY; Type 50 fracturing temporary plugging agent:
suitable for oil wells (shallow oil wells) with a temperature of 50℃-65℃;
(2) SDKX--5000XY; Type 80-O Temporary fracturing plugging agent:
suitable for oil wells with a temperature of 60℃-80℃; (deep oil wells)
(3SDKX--5000XY; 130 type temporary plugging agent: softening in the range of 80-130℃ \ 0.5-1.0 hours can be dissolved. 
4. Construction methods and precautions: The temporary plugging agent has high strength, and the dosage should be appropriately reduced according to the construction conditions when used for the first time to avoid excessive pressure to burst the pipe.
(1) The site is directly added by the sand mixer, and the adding method is simple. Adding speed Requirement: 25Kg/10s.
(2) SDKX--5000XY-2 series temporary plugging agent has high blocking strength, and the amount of on-site construction is based on the perforation thickness (80Kg-120Kg)/M, which can basically achieve effective temporary plugging of old seams The effect of blocking purpose.
(3) The product is non-toxic and tasteless, can be directly touched with hands, and needs to be stored in a dry and ventilated place.
(4) Packaging and storage;
using three-in-one packaging, four-in-one packaging, net weight 25kg;
storage should be stored in ventilated and dark, temperature 5-35 ℃. The validity period is 2 years.