Evaluation of Hydrophobic Proppant Transport by Aqueous Energized Fluids, Impact of Gas Volume Fraction and Proppant Size: A Holistic Approach
Bibliographic record
Abstract
Abstract Hydrophobically coated sand, when combined with gas injection into an appropriate fluid, provides a significant improvement in proppant transport compared to uncoated sand. This supports the expectation that gas bubbles adhering to sand particles improve transport properties. In addition, the increase of nitrogen gas volume fraction within the fracturing fluid significantly enhances proppant suspension, particularly for smaller size proppant. Proppant transport occurs by two mechanisms, suspended transport and bed transport. This study aims at determining the optimum conditions and composition for a fracturing fluid, comprised of a gas dispersed into an aqueous liquid (but not as a foam), to transport hydrophobically coated proppant. The aqueous phase is comprised of water with a friction reducer, to enhance suspension performance. The impacts of the gas volume fraction of the fluid and of the proppant particle size are studied. The experimental setup is designed to compare the proppant transport efficiency of different gaseous and/or liquid fracturing fluids. In the present case, high pressure nitrogen (13.8 MPa - 2000 psi) is dispersed within an aqueous fluid. Proppant is then injected at the entrance of a straight pipe section. This central section is equipped with several collectors where the sand can accumulate. After a specific time, the system is shut down and depressurized. Sand collection along the section provides a quantitative measurement of the proppant transport efficiency. Additionally, direct observation through sight glasses allows qualitative assessment of the transport method. The main impact of increasing the volume fraction of gas is to increase suspended transport, but we also observed a moderate improvement in bed transport. Thus, overall we observed a significant improvement in proppant transport as the gas volume fraction was increased from 10% to 30%. This effect was greatest at the smallest particle size tested, i.e. 40/70 U.S. mesh sand, but was also observed with 30/50 and 20/40 U.S. mesh sands. The upper limit on gas volume fraction was imposed by the nature of the aqueous fluid, which is not designed to operate as a foam. Phase separation effects become dominant at high gas volume fractions. The effect of particle size is attributed to the increasing number of particles present at constant loading by mass. Here we present data to support the selection of gas volume fraction for use with hydrophobically coated proppant, in order to optimize proppant transport in practical fracturing operations. These data are based directly on proppant transport measurement under high pressure conditions, which enable proper consideration of elasticity and proppant suspension effects of added gas.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".