Views: 0 Author: SEPROP Publish Time: 2026-10-10 Origin: SEPPE TECH
Ceramic proppants are essential materials in the hydraulic fracturing of oil and gas wells. Fractures that operators create during the fracturing process require proppants to maintain a specific width, ensuring a continuous flow of oil and gas toward the wellbore.
Proppant performance directly impacts transport and placement during the fracturing process, as well as conductivity after fracture closure.
Key factors to consider when selecting a proppant include particle density, particle size distribution, crush resistance, and conductivity under target closure stress.
SEPPE Ceramic Proppants encompass three main series—Lightweight, Intermediate Strength, and High Strength—and offer various mesh sizes (such as 16/30, 20/40, 30/50, and 40/70) to meet field requirements regarding fracture width, proppant transport, and conductivity.
Apparent density refers to the average density of an individual proppant particle, including any closed pores within the particle itself. Simply put, it represents the density of the single particle.
A pycnometer method is commonly used to determine particle density from the volume of displaced liquid. ISO 18753:2017 describes liquid pycnometry for determining the absolute particle density of fine ceramic powders, while proppant properties are evaluated under the applicable procedures in ISO 13503-2:2024. The test method used should therefore be identified on the report.
Test note: Ensure thorough removal of air bubbles and strict control of the liquid temperature.
Bulk density refers to the mass per unit bulk volume of proppant in its naturally settled state, accounting for both the volume of the particles and the void spaces between them. Technicians evaluate it using the applicable proppant procedure in ISO 13503-2:2024.
A lower apparent density generally improves suspension and slows settling, allowing the carrier fluid to transport proppant farther into the fracture. However, density alone does not determine suitability. Most low-density proppants are more prone to crushing under high closure stress, so actual selection must also consider reservoir conditions, fracture morphology, required crush resistance, and target conductivity.
Roundness refers to the nature of the particle edges; the smoother the edges and the fewer the sharp corners, the higher the roundness typically is.
Sphericity assesses the overall shape of the particle—checking for elongation or flatness—to determine how closely it resembles a perfect sphere.
While roundness and sphericity are distinct properties, their combined effect directly contributes to the superior fracture conductivity of ceramic proppants. High-quality ceramic proppants achieve ratings of 0.9 for both parameters, resulting in fewer inter-particle contact points, a more stable pore structure, and reduced resistance to fluid flow.
Laboratory personnel can use a binocular stereomicroscope to magnify representative ceramic proppant samples and record their sphericity and roundness values.
PSD—which assesses whether particles fall within specified sieve ranges and measures the content of oversized particles and fines—is a critical parameter in quality control.
Precise control of PSD improves proppant placement uniformity, reduces the risk of sand bridging, and optimizes pore structure. Excessive fines content leads to the filling of voids between larger particles.
Common metrics include:
Mass % Retained: The proportion of the total sample mass retained on each sieve.
Cumulative Retained %: The cumulative percentage of mass retained up to a specific sieve layer.
Fines Content: The proportion of particles smaller than the specified sieve size.
Oversize Particles: The proportion of particles larger than the specified sieve size.
For example, a 20/40 mesh designation typically indicates a target particle size range of approximately 0.425–0.850 mm.
Single-sieve retention distribution for SEPPE’s Lightweight (LWP), Intermediate Strength (ISP), and High Strength (HSP) ceramic proppants should be read from the applicable 20/40 mesh sieve report.
Learn more about ceramic proppant crush resistance testing at: How to Understand Ceramic Proppant Crush Test?
Crush resistance links closely to long-term fracture conductivity. Under reservoir closure stresses (7,500–10,000 psi or higher), proppants with insufficient strength will crush; the resulting fines fill the interstitial spaces, causing a rapid decline in conductivity and directly impacting the production decline rate of gas wells.
Values are percent fines generated at 10,000 psi. Lower values indicate greater resistance to crushing under the stated test condition.
Acid solubility evaluates the mass loss of ceramic proppants under specified acidic test conditions and links closely to long-term chemical stability.
High acid solubility indicates poor chemical stability. In acidic reservoir environments or during acidizing operations, the proppant can undergo corrosion and degradation, continuously generating fines over extended use.
A typical industry requirement is acid solubility below 7% in a solution of 12% hydrochloric acid and 3% hydrofluoric acid. In acidizing operations or sensitive reservoirs, this parameter directly determines the service life of the proppant.
Turbidity is a surface-cleanliness indicator in ceramic proppant quality reports that procurement teams often overlook, yet it remains crucial for downhole conductivity.
Excessive dust in the proppant increases friction within the tubing, accelerates equipment wear, and can even cause tubing blockage. It also reduces the final conductivity of the fracture.
According to API RP 19C / ISO 13503-2, the turbidity test method for ceramic proppants is straightforward and quantitative. Its core principle is the photometric measurement of light scattering or transmission caused by suspended fines in a liquid.
In laboratory testing, technicians typically place a specified particle size and mass of proppant in the parallel-plate test chamber of a conductivity testing apparatus. They apply the required closure stress and temperature, then pass test fluid through the proppant pack. Conductivity is calculated based on flow rate, pressure differential, and the dimensions of the test chamber.
Unlike process indicators such as bulk density, sphericity, particle size distribution, and turbidity, conductivity is not an independent property of a single particle. It is the final result of multiple proppant properties acting together and the core indicator for evaluating the production-enhancement value of ceramic proppants.
In other words, bulk density, sphericity, particle size distribution, turbidity, and other quality parameters control the factors that influence conductivity. Conductivity testing evaluates the overall flow performance of the proppant pack under specified conditions.
In practice, crush resistance, particle size distribution, density, sphericity, acid solubility, and turbidity are process metrics that control the factors affecting conductivity. Conductivity testing, on the other hand, evaluates the integrated flow performance of the proppant pack under specified conditions. Therefore, proppant selection should not be based on any single parameter but should combine target closure stress, fluid system, fracture geometry, and long-term conductivity requirements.
Views: 0 Author: SEPROP Publish Time: 2026-10-10 Origin: SEPPE TECH
Ceramic proppants are essential materials in the hydraulic fracturing of oil and gas wells. Fractures that operators create during the fracturing process require proppants to maintain a specific width, ensuring a continuous flow of oil and gas toward the wellbore.
Proppant performance directly impacts transport and placement during the fracturing process, as well as conductivity after fracture closure.
Key factors to consider when selecting a proppant include particle density, particle size distribution, crush resistance, and conductivity under target closure stress.
SEPPE Ceramic Proppants encompass three main series—Lightweight, Intermediate Strength, and High Strength—and offer various mesh sizes (such as 16/30, 20/40, 30/50, and 40/70) to meet field requirements regarding fracture width, proppant transport, and conductivity.
Apparent density refers to the average density of an individual proppant particle, including any closed pores within the particle itself. Simply put, it represents the density of the single particle.
A pycnometer method is commonly used to determine particle density from the volume of displaced liquid. ISO 18753:2017 describes liquid pycnometry for determining the absolute particle density of fine ceramic powders, while proppant properties are evaluated under the applicable procedures in ISO 13503-2:2024. The test method used should therefore be identified on the report.
Test note: Ensure thorough removal of air bubbles and strict control of the liquid temperature.
Bulk density refers to the mass per unit bulk volume of proppant in its naturally settled state, accounting for both the volume of the particles and the void spaces between them. Technicians evaluate it using the applicable proppant procedure in ISO 13503-2:2024.
A lower apparent density generally improves suspension and slows settling, allowing the carrier fluid to transport proppant farther into the fracture. However, density alone does not determine suitability. Most low-density proppants are more prone to crushing under high closure stress, so actual selection must also consider reservoir conditions, fracture morphology, required crush resistance, and target conductivity.
Roundness refers to the nature of the particle edges; the smoother the edges and the fewer the sharp corners, the higher the roundness typically is.
Sphericity assesses the overall shape of the particle—checking for elongation or flatness—to determine how closely it resembles a perfect sphere.
While roundness and sphericity are distinct properties, their combined effect directly contributes to the superior fracture conductivity of ceramic proppants. High-quality ceramic proppants achieve ratings of 0.9 for both parameters, resulting in fewer inter-particle contact points, a more stable pore structure, and reduced resistance to fluid flow.
Laboratory personnel can use a binocular stereomicroscope to magnify representative ceramic proppant samples and record their sphericity and roundness values.
PSD—which assesses whether particles fall within specified sieve ranges and measures the content of oversized particles and fines—is a critical parameter in quality control.
Precise control of PSD improves proppant placement uniformity, reduces the risk of sand bridging, and optimizes pore structure. Excessive fines content leads to the filling of voids between larger particles.
Common metrics include:
Mass % Retained: The proportion of the total sample mass retained on each sieve.
Cumulative Retained %: The cumulative percentage of mass retained up to a specific sieve layer.
Fines Content: The proportion of particles smaller than the specified sieve size.
Oversize Particles: The proportion of particles larger than the specified sieve size.
For example, a 20/40 mesh designation typically indicates a target particle size range of approximately 0.425–0.850 mm.
Single-sieve retention distribution for SEPPE’s Lightweight (LWP), Intermediate Strength (ISP), and High Strength (HSP) ceramic proppants should be read from the applicable 20/40 mesh sieve report.
Learn more about ceramic proppant crush resistance testing at: How to Understand Ceramic Proppant Crush Test?
Crush resistance links closely to long-term fracture conductivity. Under reservoir closure stresses (7,500–10,000 psi or higher), proppants with insufficient strength will crush; the resulting fines fill the interstitial spaces, causing a rapid decline in conductivity and directly impacting the production decline rate of gas wells.
Values are percent fines generated at 10,000 psi. Lower values indicate greater resistance to crushing under the stated test condition.
Acid solubility evaluates the mass loss of ceramic proppants under specified acidic test conditions and links closely to long-term chemical stability.
High acid solubility indicates poor chemical stability. In acidic reservoir environments or during acidizing operations, the proppant can undergo corrosion and degradation, continuously generating fines over extended use.
A typical industry requirement is acid solubility below 7% in a solution of 12% hydrochloric acid and 3% hydrofluoric acid. In acidizing operations or sensitive reservoirs, this parameter directly determines the service life of the proppant.
Turbidity is a surface-cleanliness indicator in ceramic proppant quality reports that procurement teams often overlook, yet it remains crucial for downhole conductivity.
Excessive dust in the proppant increases friction within the tubing, accelerates equipment wear, and can even cause tubing blockage. It also reduces the final conductivity of the fracture.
According to API RP 19C / ISO 13503-2, the turbidity test method for ceramic proppants is straightforward and quantitative. Its core principle is the photometric measurement of light scattering or transmission caused by suspended fines in a liquid.
In laboratory testing, technicians typically place a specified particle size and mass of proppant in the parallel-plate test chamber of a conductivity testing apparatus. They apply the required closure stress and temperature, then pass test fluid through the proppant pack. Conductivity is calculated based on flow rate, pressure differential, and the dimensions of the test chamber.
Unlike process indicators such as bulk density, sphericity, particle size distribution, and turbidity, conductivity is not an independent property of a single particle. It is the final result of multiple proppant properties acting together and the core indicator for evaluating the production-enhancement value of ceramic proppants.
In other words, bulk density, sphericity, particle size distribution, turbidity, and other quality parameters control the factors that influence conductivity. Conductivity testing evaluates the overall flow performance of the proppant pack under specified conditions.
In practice, crush resistance, particle size distribution, density, sphericity, acid solubility, and turbidity are process metrics that control the factors affecting conductivity. Conductivity testing, on the other hand, evaluates the integrated flow performance of the proppant pack under specified conditions. Therefore, proppant selection should not be based on any single parameter but should combine target closure stress, fluid system, fracture geometry, and long-term conductivity requirements.
