Hi*

I'm analyzing the technical (via HYSYS) and economic performance of different deep cut turboexpander plant configurations for natural gas processing as part of a personal project.

This area (Northwestern Alberta) has the following natural gas supply chain:

Wells (product: wet rich (raw) natural gas) -> shallow cut gas plant (products: dry rich natural gas* condensate) -> deep cut turboexpander plant (products: dry lean natural gas* y-grade NGL) -> fractionation plant (products: ethane* propane* butane* and pentane+)

I'm trying to estimate the selling price for y-grade NGLs (also know as natural gas liquids (NGLs) mix* C2+/C3+)* which is a mixture of ethane* propane* butane* pentane+). Y-Grade NGLs are not a commonly-traded commodity* hence I couldn't find pricing information online. It is a mix of NGLs that is sold to a 3rd-party that is operating a fractionator* which produces pure products (ethane* propane* butane* pentane+). Y-Grade NGLs are C2+ or C3+* depending on the turboexpander plant configuration.

How would you estimate the selling price for y-grade NGLs?

I think the best approach is estimate the value of the mix of NGLs in the y-grade* then subtract the fractionator plant costs and profit margin.

For example:
Y-grade NGL mix: 57 mol % C2* 21 mol % C3* 10 mol % C4* 12 mol % C5+
Prices: 18 CAD/bbl C2* 42 CAD/bbl C3* 52 CAD/bbl C4* 70 CAD/bbl C5+
Value of y-grade NGL mix after fractionation: 33 CAD/bbl (weighted average)
For the fractionator (on a per bbl basis): Profit = Revenue - Cost of y-grade NGL – all other costs
Cost of y-grade NGL = Revenue (which is 33 CAD/bbl) - all other costs – Profit

This cost of y-grade NGL for the fractionator is the revenue from y-grade NGL sales for the deep cut plant turboexpander.

Does anyone have better ideas/resources for estimating the selling price of y-grade? If not* how would you estimate the costs/profit margin of fractionation plants?

Thank you