Al-Diwiniya atmospheric operating reference
AlDiwiniyaAtmosphericReference makes a public atmospheric crude-unit case available to Java and Python/JPype callers without turning missing source data into model inputs.
Source and license
The source is Ahmed Qasim, Hyfaa Yousif, and Nazar Qasim, Simulation of Atmospheric Distillation Unit for AL-Diwiniya Crude Oil Refinery by Using Aspen Hysys, Journal of Petroleum Research and Studies 15(3), 85-97, published 21 September 2025, DOI 10.52716/jprs.v15i3.965. The open-access article is licensed CC BY 4.0.
The case describes a 10,000 barrel/day Al-Diwiniya refinery atmospheric unit processing 66 m3/h of 2021 Basra medium crude. The reported crude has API gravity 29.8 at 15 degC, density 876 kg/m3 at an unstated reference temperature, sulfur 3 mass%, salt 159 ppm, water and bottom sediment 0.15 vol%, and kinematic viscosity 12.7 cSt at 20 degC.
Preserved evidence
The reference preserves all 17 published crude TBP coordinates:
| Cumulative liquid volume (%) | 2 | 3.5 | 5 | 7.5 | 10 | 12.5 | 15 | 17.5 | 20 | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| TBP temperature (degC) | 40 | 52 | 62 | 77 | 95 | 112 | 128 | 143 | 159 | 189 | 218 | 249 | 279 | 310 | 342 | 373 | 405 |
This is explicitly a partial curve. NeqSim does not create synthetic 0 or 100 vol% endpoints, interpolate the unreported 60-100 vol% residue, or assign one bulk density to all TBP intervals.
The operating reference also records:
- crude preheat from 25 to 150 degC and furnace heating to a 300 degC column feed;
- 29 stages, with the feed flash zone between trays 3 and 4;
- 1.5 barg feed pressure, 0.75 barg top pressure, and 1.2 barg bottom pressure;
- heavy-naphtha draws at trays 24 and 22, kerosene at tray 15, and gasoil at tray 9;
- a 3 m3/h gasoil pump-around returned at 60 degC;
- four-stage kerosene and gasoil side strippers using 75 and 125 kg/h steam;
- 300 kg/h bottom steam at 220 degC and 5 barg.
Product operating rows
| Product | Plant rate (m3/h) | HYSYS rate (m3/h) | Plant draw (degC) | HYSYS draw (degC) |
|---|---|---|---|---|
| Light naphtha | 8 | 8 | 110 | 109 |
| Total heavy naphtha | 2 | 2 | 135 | 140 |
| Kerosene | 4 | 4 | 180 | 190 |
| Gasoil | 10 | 10 | 240 | 235 |
| Atmospheric residue | 41 | 41.25 | 295 | 295 |
| Off gas | 1 | 0.75 | 60 | 65 |
The source uses signed relative error 100 * (plant - HYSYS) / plant. ProductReference exposes the raw values and recomputes that convention. The five measured hydrocarbon-liquid product rates total 65 m3/h, or 98.4848% of the 66 m3/h crude feed. Off-gas and the separately reported 0.4 m3/h water stream are retained but excluded from this liquid-volume closure because the source does not state compatible reference conditions.
Java and Python access
double[] volumePercent = AlDiwiniyaAtmosphericReference.getTbpCumulativeVolumePercent();
double[] temperatureCelsius = AlDiwiniyaAtmosphericReference.getTbpTemperatureCelsius();
AlDiwiniyaAtmosphericReference.ProductReference kerosene =
AlDiwiniyaAtmosphericReference.getProduct("Kerosene");
double plantDrawCelsius = kerosene.getPlantDrawTemperatureCelsius();
double signedErrorPercent = kerosene.getDrawTemperatureRelativeErrorPercent();
The static methods are directly accessible through JPype. Returned arrays are defensive copies; changing a Python or Java copy cannot mutate the frozen source data.
Scientific boundary
The paper states that all HYSYS product flow rates were fixed. Equality of light-naphtha, heavy-naphtha, kerosene, and gasoil rates is therefore not independent product-yield validation. Product draw temperatures were calculated and can support a future operating-envelope comparison, but the source does not publish the cut-density curve, molecular-weight curve, complete crude TBP tail, numeric product ASTM D86 tables, reflux rate, or all heat duties needed for an independently reproducible 29-stage crude-column model.
This increment qualifies public data retention, units, error conventions, and evidence classification. It does not claim to validate NeqSim product yields, pseudo-component properties, or the Al-Diwiniya column. A future process-model comparison must add sufficient public assay and product-quality data without tuning to imposed rates.