Enter crude feed and cut yields
Sample crude and yield split
| Item | Example value | Notes |
|---|---|---|
| Feed rate | 100,000 bbl/day | Atmospheric crude charge rate |
| API gravity | 33 | Used to estimate density when SG is blank |
| Liquid recovery | 96% | Liquid products from feed (excluding losses) |
| Losses | 2% gas, 1% water, 1% other | Optional planning allowance; set to zero if embedded |
| Yield basis | Percent of recovered liquid | Cuts sum to 100% of the liquid pool |
| Product | Yield (%) | bbl/day (from 96,000 liquid bbl/day) |
|---|---|---|
| LPG / Refinery Gas | 4 | 3,840 |
| Light Naphtha | 8 | 7,680 |
| Heavy Naphtha | 10 | 9,600 |
| Kerosene / Jet | 10 | 9,600 |
| Diesel / Gas Oil | 22 | 21,120 |
| Atmospheric Gas Oil | 16 | 15,360 |
| Vacuum Gas Oil | 12 | 11,520 |
| Atmospheric Residue | 18 | 17,280 |
How yields and flows are calculated
- Convert density (if needed): SG is taken from your input, or derived from API. Density ≈ SG × 999.016 kg/m³.
- Normalize feed rate: Convert between bbl/day, m³/day, and t/day using density and 1 bbl = 0.1589873 m³.
- Liquid product pool: Liquid pool (bbl/day) = Feed (bbl/day) × Liquid recovery (%)/100.
- Product flow:
- If yields are percent of recovered liquid: Product (bbl/day) = Liquid pool × Yield(%)/100.
- If yields are percent of feed: Product (bbl/day) = Feed × Yield(%)/100.
- Optional normalization: Rescales your cut list to total 100% (recovered basis) or to the liquid recovery% (feed basis).
Steps for reliable results
- Enter the crude feed rate and choose volume or mass basis.
- Provide API gravity or specific gravity so density can be estimated.
- Set liquid recovery and any planning losses you want to track.
- Select the yield basis that matches your assay or operating data.
- Enter cut yields for your product slate, then submit.
- Download CSV or PDF for reporting and documentation.
What the yield slate represents
A crude distillation yield slate is a planning snapshot of how a crude charge splits into products after atmospheric separation. It combines crude quality, operating cut points, and recovery assumptions into one consistent list. Results are most useful when the yield basis is clearly stated: percent of recovered liquid or percent of feed. With a stable basis, the slate becomes a comparable benchmark across crudes, campaigns, and operating modes for unit economics.
Key drivers of atmospheric cut yields
Atmospheric yields are governed by the crude assay curve and the temperatures chosen for each draw. Heavier crudes shift volume toward gas oils and residue, while lighter crudes increase naphtha and kerosene. Heater outlet temperature, column pressure, and reflux control separation sharpness and overlap. Tight cut points can protect downstream quality but reduce apparent yield in lighter cuts. When comparing slates, keep cut definitions consistent and document any endpoint changes between runs.
Interpreting liquid recovery and losses
Liquid recovery is the portion of feed counted as liquid products, before or after losses depending on your convention. Losses include gas and light ends not captured, free water removed in treating, and handling losses to slop or flare. Many sites apply a small allowance, often one to four percent, during early planning. If your assay yields already include these effects, set losses to zero and treat recovery as implicit in calculations.
Using mass conversion for planning
Converting volumes to mass helps with logistics, blending limits, and emissions accounting. This calculator estimates density from specific gravity or API, then applies that density across all product streams for a first pass. For rigorous studies, replace the single density with product densities or temperature corrected values, because naphtha and residue can differ materially. Still, the approximation is valuable to size tanks, plan shipping tonnage, and reconcile feed availability with monthly targets.
Quality checks before sharing results
Before circulating results, perform checks that improve credibility. Confirm the cut yields sum to the expected target and note whether normalization was applied. Review the balance difference against the liquid pool; large gaps usually indicate mixed yield bases or missing products. Compare the slate to unit constraints such as naphtha stabilizer capacity, diesel hydrotreat limits, and residue handling. Finally, run a sensitivity case for cut points to understand risk around forecasted margins.
FAQs
What should I enter for liquid recovery?
Use your site’s historical recovery for similar crudes and cut points. If unknown, start with a conservative value and refine after comparing forecasts to unit test runs and monthly yield accounting.
Should yields be percent of feed or recovered liquid?
Use recovered-liquid basis when your cut list is a normalized product split. Use feed basis when the assay or planning dataset reports each product as a fraction of total crude charge.
Why does the mass output look inaccurate?
Mass is estimated using one density for all streams. Lighter and heavier products can have different densities. For better accuracy, calculate with product densities or temperature-corrected values and treat this output as a planning approximation.
How do I use assay data with this tool?
Take the assay’s cut yields and confirm the same cut endpoints are used. Select the matching yield basis, enter losses if they are not embedded, and enable normalization to align totals with your chosen recovery convention.
Can this calculator model vacuum column products?
It provides a simplified split for planning and can include VGO and residue as proxy cuts. For detailed vacuum modeling, you would typically separate LVGO/HVGO, slop wax, and pitch using unit-specific data.
What does normalization change?
Normalization rescales your entered yields so totals match the selected basis target. It prevents small input errors from breaking the balance and makes comparisons cleaner when cut lists come from different sources.