Experimental Evaluation of Fouling Processes in Porous Polyethylene Well Screens Used for Horizontal Wells
Bibliographic record
Abstract
Abstract The hydraulic performance of porous polyethylene well screens was examined in laboratory columns to understand the processes that affect well performance in many field applications. Conditions studied included (1) well‐screen pore size; (2) the presence of biodegradable drilling fluid, biological electron acceptors, and biofouling organisms; and (3) chlorine development. Custom‐fabricated, segmentable acrylic columns (8.9 cm diameter. 64 cm length) were employed using a factorial design statistical approach to mimic a variety of representative field conditions experienced during field applications. After circular well‐screen coupons (circular sections of the well screen cut to match the diameter of the columns) were cut and secured horizontally in the columns, sand media, and, in some cases, biodegradable drilling fluid were packed on top of the well screens. Those columns receiving chlorine development were allowed to sit overnight after a 1000 ppm chlorine solution was introduced beneath the well screen following upflow saturation. The columns were upflow saturated and then operated with simulated ground water in a down flow mode under constant hydraulic head for up to 75 days. Residual head with depth was measured and flux density values were recorded over time. Effluent samples were collected and analyzed for dissolved oxygen (D.O.), electrical conductance, pH, and total solids. After achieving pseudo‐steady‐state throughput condition as indicated by relatively constant effluent flux densities, the columns were dismantled and the well‐screen coupons were examined under a scanning electron microscope to observe causes of any loss in flow observed. The hydraulic conductivities of the well screens were also measured before and after operation in the columns. Results show that these porous polyethylene well screens resist fouling due to microbial colonization or chemical precipitation. Scanning electron microscopy revealed little or no colonization of the surfaces by microbes or blockage of pores by particle entrapment. Hydraulic head measurements revealed that the cause of headloss in the columns was a result of processes that occurred in the overlying sand media and not within the well screens themselves.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| 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) | 0.000 | 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 teacher head, 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".