Coupled sulfur/nitrogen hydrotreating economics scenario-delta receipt
RefineryHydrotreatingSulfurNitrogenEconomicsScenarioDeltaReceipt compares two caller-priced screening scenarios over the same qualified physical receipt. It reports candidate-minus-baseline price, value, cost, and screening-margin deltas and attributes the margin change to the three caller-owned scenario inputs.
No default price, market forecast, or economic datum is embedded in NeqSim. The public DOE Big Hill Sweet case remains provenance for the already-qualified assay-derived sulfur and nitrogen inputs and upstream physical bookkeeping. All illustrative prices are hypothetical caller inputs.
Calculation contract
For unchanged qualified liquid-product, export-gas, and feed rates $\dot{m}_L$, $\dot{m}_G$, and $\dot{m}_F$ in t/h, define candidate-minus-baseline price and feed-cost changes $\Delta p_L$, $\Delta p_G$, and $\Delta c_F$.
$\Delta M_L = \dot{m}_L \Delta p_L, \qquad \Delta M_G = \dot{m}_G \Delta p_G, \qquad \Delta M_F = -\dot{m}_F \Delta c_F$
The attributed screening-margin change is:
$\Delta M_{\mathrm{attr}} = \Delta M_L + \Delta M_G + \Delta M_F$
Four explicit residuals independently close product-value delta, variable-cost delta, screening-margin delta, and price attribution. Signed contributions are preserved; an unfavorable price or higher feed cost produces a negative contribution.
The baseline and candidate must share the same in-memory qualified net product-intensity receipt. This identity requirement prevents a change in throughput, yield, energy, emissions, or operating cost from being mislabeled as a price effect. Compare different physical cases with a separate engineering comparison that exposes their changed physical assumptions.
Illustrative public case
The retained Big Hill scenario uses 1000 kg/h feed, 995.4894479786512 kg/h liquid product, and 7.61202393313295 kg/h export gas. A hypothetical baseline of 600 currency/t liquid product, 100 currency/t export gas, and 450 currency/t feed is compared with a candidate of 625, 80, and 460 currency/t on the same respective bases:
| Result | Candidate minus baseline |
|---|---|
| Liquid-product price | 25.0 currency/t |
| Export-gas price | -20.0 currency/t |
| Feed cost | 10.0 currency/t |
| Liquid-product margin contribution | 24.88723619946628 currency/h |
| Export-gas margin contribution | -0.152240478662659 currency/h |
| Feed-cost margin contribution | -10.0 currency/h |
| Total product-value delta | 24.73499572080362 currency/h |
| Total variable-cost delta | 10.0 currency/h |
| Screening-margin delta | 14.73499572080362 currency/h |
The attributed contribution sum equals the screening-margin delta within 1e-9 currency/h. Throughput scaling preserves the three caller-input deltas and scales the hourly contributions and margin delta with the qualified mass rates.
Acceptance and exclusions
The receipt fails closed for missing scenarios, distinct upstream physical receipts, non-finite arithmetic, or closure outside 1e-9 currency/h. An unchanged scenario returns zero deltas, and adverse scenarios retain signed negative margin changes.
This capability is deterministic same-physical-case screening attribution. It is not a multi-variable solver, optimizer, market forecast, product-quality model, lifecycle assessment, fixed-cost model, capital estimate, depreciation schedule, tax or financing model, probability model, profitability forecast, or investment-decision method. It does not infer export-gas heating value, composition quality, sales specification, or commercial acceptability.